Materials
212 Questions
4 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is a primary advantage of using composite materials in aircraft construction?

  • High maintenance requirements
  • High thermal conductivity
  • Low corrosion resistance
  • High strength-to-weight ratio (correct)

    • What is a characteristic of ceramic materials used in aircraft applications?

  • Low strength-to-weight ratio
  • High thermal conductivity
  • Low corrosion resistance
  • High thermal resistance (correct)

    • Which steel alloy is commonly used in aircraft landing gear and engine components?

  • 6061-T6
  • 7075-T6
  • 4130 (correct)
  • 2024-T3

    • Which aluminum alloy is commonly used in aircraft skin and fuselage?

    <p>6061-T6</p> Signup and view all the answers

    What is a potential application of nanomaterials in aircraft construction?

    <p>High-temperature resistant coatings</p> Signup and view all the answers

    What is a consideration when welding aircraft materials?

    <p>Weld joint design</p> Signup and view all the answers

    Which type of material has structures or components on the nanoscale (typically 1-100 nm)?

    <p>Nanomaterials</p> Signup and view all the answers

    What is an advantage of using ceramic materials in aircraft applications?

    <p>Corrosion resistance</p> Signup and view all the answers

    Which aluminum alloy is commonly used in aircraft landing gear and engine components?

    <p>7075-T6</p> Signup and view all the answers

    What is a characteristic of composite materials used in aircraft structures?

    <p>Low maintenance requirements</p> Signup and view all the answers

    Which heat treatment process involves quenching steel in a molten salt bath or oil to achieve a specific microstructure?

    <p>Austempering</p> Signup and view all the answers

    What is the minimum percentage of chromium required in Martensitic Steel?

    <p>11.5%</p> Signup and view all the answers

    Which type of steel alloy contains chromium and molybdenum?

    <p>Chromoly</p> Signup and view all the answers

    What is the primary goal of the austempering heat treatment process?

    <p>To achieve a combination of high strength, toughness, and resistance to corrosion and fatigue</p> Signup and view all the answers

    Which type of steel alloy is often used in critical aircraft structures such as engine mounts and wing components?

    <p>High-strength Alloy</p> Signup and view all the answers

    What is the purpose of the tempering heat treatment process?

    <p>To reduce the hardness of steel and increase its toughness</p> Signup and view all the answers

    Which heat treatment process involves heating steel in a nitrogen atmosphere to achieve high surface hardness and wear resistance?

    <p>Nitriding</p> Signup and view all the answers

    What is a characteristic of Chromoly steel?

    <p>High strength and toughness</p> Signup and view all the answers

    Which heat treatment process involves heating steel to a critical temperature, then slowly cooling it to relieve internal stresses and achieve a specific microstructure?

    <p>Annealing</p> Signup and view all the answers

    What is a common application of Martensitic Steel?

    <p>Aircraft landing gear and engine mounts</p> Signup and view all the answers

    What is the name of the iron alloy that contains 2.1 to 4.3% carbon?

    <p>Carbon Steel</p> Signup and view all the answers

    Which microstructure is a combination of Ferrite and Cementite?

    <p>Pearlite</p> Signup and view all the answers

    What is the term for steels that contain Ferrite as the primary microstructure?

    <p>Ferritic</p> Signup and view all the answers

    What is the name of the microstructure that is formed when steel is rapidly cooled?

    <p>Martensite</p> Signup and view all the answers

    What is the term for steels that contain Austenite as the primary microstructure?

    <p>Austenitic</p> Signup and view all the answers

    Which alloy group has excellent corrosion resistance and high thermal and electrical conductivity?

    <p>1000 series</p> Signup and view all the answers

    What is the principal alloying element in the 2000 series alloy group?

    <p>Copper</p> Signup and view all the answers

    Which alloy group has moderate strength and good working characteristics?

    <p>3003</p> Signup and view all the answers

    What is indicated by the second digit in the alloy designation in the 2xxx through 8xxx alloy groups?

    <p>Alloy modifications</p> Signup and view all the answers

    Which element is a major impurity in the 1000 series alloy group?

    <p>Iron</p> Signup and view all the answers

    Which alloy group has optimum properties equal to mild steel after solution heat treatment?

    <p>2000 series</p> Signup and view all the answers

    Which alloy series is known for its good welding and corrosion resistant characteristics?

    <p>5000 series</p> Signup and view all the answers

    What is the primary alloying element in the 4000 series of aluminum alloys?

    <p>Silicon</p> Signup and view all the answers

    Which alloy series is heat-treatable and has corrosion resistant characteristics?

    <p>6000 series</p> Signup and view all the answers

    What is the principal alloying element in the 7000 series of aluminum alloys?

    <p>Zinc</p> Signup and view all the answers

    Which alloy is known for its very high strength and corrosion resistant characteristics?

    <p>7075</p> Signup and view all the answers

    What is the result of coupling zinc with magnesium in the 7000 series alloys?

    <p>Heat-treatable alloys of very high strength</p> Signup and view all the answers

    Which alloy series has a limited response to heat treatment when used in welding heat-treatable alloys?

    <p>4000 series</p> Signup and view all the answers

    What is the composition of the 6061 alloy?

    <p>0.25% Cu, 0.6% Si, 1.3% Mg, 0.25% Zn</p> Signup and view all the answers

    Which alloy has exceptional high strength, toughness, and corrosion resistance?

    <p>Manganese bronze</p> Signup and view all the answers

    What is the primary advantage of using cast aluminum bronze in bearings and pump parts?

    <p>High corrosion resistance</p> Signup and view all the answers

    Which alloy contains about 95 percent copper, 3 percent silicon, and 2 percent manganese, zinc, iron, tin, and aluminum?

    <p>Silicon bronze</p> Signup and view all the answers

    What is the approximate percentage of nickel in Monel?

    <p>68 percent</p> Signup and view all the answers

    Which property makes aluminum bronzes suitable for diaphragms, gears, and pumps?

    <p>Great strength, hardness, and resistance to both shock and fatigue</p> Signup and view all the answers

    What is the primary advantage of using cast aluminum bronze in areas exposed to salt water and corrosive gases?

    <p>Excellent resistance to corrosion, shock, and fatigue</p> Signup and view all the answers

    Which alloy can be formed, extruded, drawn, or rolled to any desired shape?

    <p>Manganese bronze</p> Signup and view all the answers

    What is the primary application of manganese bronze in rod form?

    <p>Machined parts for aircraft landing gears and brackets</p> Signup and view all the answers

    What is the carbon percentage range in medium carbon steel?

    <p>0.30 to 0.50 percent</p> Signup and view all the answers

    What type of steel is SAE 1035?

    <p>Medium carbon steel</p> Signup and view all the answers

    What is the primary element added to steel to increase its hardness?

    <p>Carbon</p> Signup and view all the answers

    What is the designation for Nickel-Chromium steel?

    <p>SAE 30xx</p> Signup and view all the answers

    What is the primary element added to steel to increase its corrosion resistance?

    <p>Chromium</p> Signup and view all the answers

    What is the designation for Manganese steel?

    <p>SAE 13xx</p> Signup and view all the answers

    What is the designation for Chromium-Molybdenum steel?

    <p>SAE 41xx</p> Signup and view all the answers

    What is the primary benefit of adding nickel to carbon steel?

    <p>Increased hardness and tensile strength</p> Signup and view all the answers

    What type of steel is commonly used for making flat springs and coil springs?

    <p>SAE 1095</p> Signup and view all the answers

    What is the primary characteristic of chromium steel?

    <p>High hardness and strength</p> Signup and view all the answers

    What is the primary advantage of using stainless steel in aircraft construction?

    <p>Increased strength and corrosion resistance</p> Signup and view all the answers

    What is the composition of 18-8 steel?

    <p>18% chromium, 8% nickel</p> Signup and view all the answers

    What is the primary use of SAE 2330 steel?

    <p>Aircraft parts such as bolts, terminals, keys, clevises, and pins</p> Signup and view all the answers

    What is the effect of cold working on 18-8 steel?

    <p>Increased strength</p> Signup and view all the answers

    What is the approximate percentage of nickel in Monel?

    <p>68</p> Signup and view all the answers

    What is the primary advantage of using K-Monel in aircraft?

    <p>Corrosion resistance and nonmagnetic properties</p> Signup and view all the answers

    What is the tensile strength of Monel when forged and annealed?

    <p>80,000 psi</p> Signup and view all the answers

    Which of the following is a characteristic of Nickel alloys?

    <p>High strength and corrosion resistance</p> Signup and view all the answers

    What is the primary application of Inconel alloys?

    <p>Exhaust systems that require high strength and corrosion resistance</p> Signup and view all the answers

    What is K-Monel used for in aircraft?

    <p>Gears and structural members</p> Signup and view all the answers

    What is the result of adding a small amount of aluminum to the Monel formula?

    <p>K-Monel</p> Signup and view all the answers

    What is the primary advantage of using chrome-molybdenum steel in aircraft construction?

    <p>High toughness and wear resistance</p> Signup and view all the answers

    What is the typical carbon content of chrome-molybdenum steel used in aircraft construction?

    <p>0.25 to 0.55 percent</p> Signup and view all the answers

    What is the purpose of adding molybdenum to chromium steel?

    <p>To raise the ultimate strength of steel without affecting ductility or workability</p> Signup and view all the answers

    What is the primary difference between Inconel and stainless steel?

    <p>Inconel has a higher nickel content</p> Signup and view all the answers

    What is the advantage of using SAE 6150 steel for making springs?

    <p>It has high toughness and resistance to wear and fatigue</p> Signup and view all the answers

    What is the typical application of chrome-vanadium steel with high carbon content?

    <p>Manufacturing ball and roller bearings</p> Signup and view all the answers

    What is the benefit of using chrome-molybdenum steel for welded structural parts and assemblies?

    <p>It is adaptable for welding and has high strength</p> Signup and view all the answers

    What is the primary reason why nickel Inconel alloys are used in turbine engines?

    <p>Their high corrosion resistance under extremely high-temperature conditions</p> Signup and view all the answers

    What is the purpose of applying a drop of cupric chloride and hydrochloric acid solution to a metal sample?

    <p>To identify the type of metal</p> Signup and view all the answers

    What is the most important consideration when selecting substitute metals for aircraft repair and maintenance?

    <p>Maintaining original strength</p> Signup and view all the answers

    What is the primary method of metalworking used for steel?

    <p>Hot working</p> Signup and view all the answers

    What is the result of the hot working process on an ingot?

    <p>The surface is solid, but the interior is still molten</p> Signup and view all the answers

    What is the purpose of the four requirements when selecting substitute metals?

    <p>To ensure the metal meets the original structural requirements</p> Signup and view all the answers

    What is the difference between the result of the cupric chloride and hydrochloric acid solution test on nickel Inconel and stainless steel?

    <p>Nickel Inconel turns shiny, while stainless steel turns copper-colored</p> Signup and view all the answers

    What is a characteristic of aluminum bronzes?

    <p>High degree of resistance to corrosion</p> Signup and view all the answers

    What percentage of aluminum is typically present in aluminum bronzes?

    <p>Up to 16 percent</p> Signup and view all the answers

    What is the primary application of cast aluminum bronze?

    <p>Bearings and pump parts</p> Signup and view all the answers

    What is the composition of Monel?

    <p>68 percent copper, 29 percent nickel, 0.2 percent iron, 1 percent manganese</p> Signup and view all the answers

    What is the primary advantage of using manganese bronze?

    <p>High strength and corrosion resistance</p> Signup and view all the answers

    What is the composition of silicon bronze?

    <p>95 percent copper, 3 percent silicon, 2 percent manganese, zinc, iron, tin, and aluminum</p> Signup and view all the answers

    What is the primary application of manganese bronze in rod form?

    <p>Machined parts for aircraft landing gears and brackets</p> Signup and view all the answers

    What is the primary advantage of using cast aluminum bronze in areas exposed to salt water and corrosive gases?

    <p>Good corrosion resistance and high strength</p> Signup and view all the answers

    What is the characteristic of silicon bronze?

    <p>High strength and great corrosion resistance</p> Signup and view all the answers

    What is the primary advantage of using aluminum bronzes?

    <p>Good corrosion resistance and high strength</p> Signup and view all the answers

    What is a characteristic of Chrome-Molybdenum steel?

    <p>It has high strength, toughness, and resistance to wear and fatigue.</p> Signup and view all the answers

    What is the advantage of using Chrome-Molybdenum steel in aircraft construction?

    <p>It has high strength and resistance to wear and fatigue.</p> Signup and view all the answers

    What is Inconel?

    <p>A nickel-chromium-iron alloy.</p> Signup and view all the answers

    What is the main characteristic of nickel steel?

    <p>High hardness, tensile strength, and elastic limit</p> Signup and view all the answers

    Why are identifying tests necessary for Inconel and stainless steel?

    <p>Because they have similar appearances.</p> Signup and view all the answers

    What is a characteristic of Chrome-Vanadium steel?

    <p>It has high carbon content.</p> Signup and view all the answers

    What is the primary use of SAE 1095 steel?

    <p>Making flat springs and coil springs</p> Signup and view all the answers

    What is the primary advantage of using Molybdenum in steel alloys?

    <p>It raises the ultimate strength of the steel without affecting ductility or workability.</p> Signup and view all the answers

    What is the main advantage of chromium steel?

    <p>High hardness, strength, and corrosion-resistant properties</p> Signup and view all the answers

    What is the main difference between Chrome-Molybdenum steel and carbon steel?

    <p>Chrome-Molybdenum steel has higher strength and resistance to wear and fatigue.</p> Signup and view all the answers

    What is the composition of 18-8 steel?

    <p>18% chromium, 8% nickel</p> Signup and view all the answers

    What is the main difference between stainless steel and mild steel?

    <p>Stainless steel expands more than mild steel</p> Signup and view all the answers

    What is the typical carbon percentage range in SAE 6150?

    <p>0.25 to 0.55%</p> Signup and view all the answers

    What is the primary application of chrome-vanadium steel?

    <p>Not mentioned in the content</p> Signup and view all the answers

    What is the main advantage of using stainless steel in aircraft construction?

    <p>Corrosion resistance and high thermal conductivity</p> Signup and view all the answers

    What is the effect of cold working on 18-8 steel?

    <p>It increases its strength</p> Signup and view all the answers

    What is the carbon percentage range in medium carbon steel?

    <p>0.30 to 0.50 percent</p> Signup and view all the answers

    What type of steel is SAE 1035?

    <p>Medium carbon steel</p> Signup and view all the answers

    What is the primary element added to steel to increase its hardness?

    <p>Carbon</p> Signup and view all the answers

    What series of steel contains Nickel 3.50% and Chromium 1.55%?

    <p>33xx</p> Signup and view all the answers

    What series of steel contains Molybdenum 0.20 or 0.25%?

    <p>40xx</p> Signup and view all the answers

    What series of steel contains Chromium 0.50, or 0.40 or 0.50%?

    <p>50xx</p> Signup and view all the answers

    What series of steel contains Nickel 0.30%, Chromium 0.40%, Molybdenum 0.12%?

    <p>81xx</p> Signup and view all the answers

    What series of steel contains Manganese 0.85%, Silicon 2.00%, Chromium 0 or 0.35%?

    <p>92xx</p> Signup and view all the answers

    What is the primary advantage of using chrome-molybdenum steel in aircraft construction?

    <p>It has high weldability and adaptability to high temperature service</p> Signup and view all the answers

    What is the percentage range of molybdenum in chrome-molybdenum steel used in aircraft construction?

    <p>0.15 to 0.25%</p> Signup and view all the answers

    Which of the following is a characteristic of chrome-molybdenum steel?

    <p>It is ductile and resistant to fatigue</p> Signup and view all the answers

    What is the primary application of Inconel in aircraft construction?

    <p>Exhaust systems and heat shields</p> Signup and view all the answers

    What is the method of identification used to distinguish between Inconel and stainless steel?

    <p>Electrochemical technique</p> Signup and view all the answers

    What is the primary advantage of using chrome-molybdenum steel over carbon steel in aircraft construction?

    <p>It is more weldable and adaptable to high temperature service</p> Signup and view all the answers

    What is the approximate carbon content range of SAE 6150 steel?

    <p>0.50 to 0.60%</p> Signup and view all the answers

    What is the primary alloying element in chrome-molybdenum steel?

    <p>Chromium</p> Signup and view all the answers

    What is the primary advantage of using chrome-nickel steel in aircraft construction?

    <p>It has high corrosion resistance</p> Signup and view all the answers

    What is the effect of nickel on the properties of carbon steel?

    <p>It increases the hardness, tensile strength, and elastic limit</p> Signup and view all the answers

    What is the approximate percentage of vanadium in chrome-vanadium steel?

    <p>1%</p> Signup and view all the answers

    Which type of steel is commonly used for making coil springs?

    <p>SAE 1095</p> Signup and view all the answers

    What is the primary alloy of stainless steel?

    <p>Chromium</p> Signup and view all the answers

    What is a common application of 18-8 steel in aircraft construction?

    <p>Fabrication of exhaust collectors</p> Signup and view all the answers

    What is the effect of cold working on 18-8 steel?

    <p>It increases its strength</p> Signup and view all the answers

    Which type of steel is high in hardness, strength, and corrosion-resistant properties?

    <p>Chromium steel</p> Signup and view all the answers

    What is the carbon percentage range in high carbon steel?

    <p>0.50 to 1.05 percent</p> Signup and view all the answers

    What is SAE 1035 steel used for?

    <p>Light forgings and rod ends</p> Signup and view all the answers

    What is the primary element added to steel to increase its hardness in 40xx series?

    <p>Molybdenum</p> Signup and view all the answers

    What is the primary element added to steel to increase its hardness in 50xx series?

    <p>Chromium</p> Signup and view all the answers

    What is the primary element added to steel to increase its hardness in 33xx series?

    <p>Nickel and chromium</p> Signup and view all the answers

    What is the primary element added to steel to increase its hardness in 46xx series?

    <p>Nickel and molybdenum</p> Signup and view all the answers

    What is the primary element added to steel to increase its hardness in 47xx series?

    <p>Nickel, chromium, and molybdenum</p> Signup and view all the answers

    What is the primary element added to steel to increase its hardness in 61xx series?

    <p>Vanadium</p> Signup and view all the answers

    What is the primary effect of adding nickel to carbon steel?

    <p>It increases the hardness and tensile strength</p> Signup and view all the answers

    What is the primary application of Chromium Steel?

    <p>Heat-treated forgings that require greater toughness and strength</p> Signup and view all the answers

    What is the corrosion-resistant degree of Chrome-nickel Steel determined by?

    <p>Surface condition of the metal, as well as composition, temperature, and concentration of the corrosive agent</p> Signup and view all the answers

    What is the principal alloy of Stainless Steel?

    <p>Chromium</p> Signup and view all the answers

    What is a distinctive feature of 18-8 Steel?

    <p>Cold working increases its strength</p> Signup and view all the answers

    What is the composition of Chrome-vanadium Steel?

    <p>Approximately 18 percent vanadium and 1 percent chromium</p> Signup and view all the answers

    What is a challenge when welding Stainless Steel?

    <p>It expands about 50 percent more than mild steel and conducts heat only about 40 percent as rapidly</p> Signup and view all the answers

    What can be used for almost any part of an aircraft?

    <p>Stainless Steel</p> Signup and view all the answers

    What is a characteristic of chrome-molybdenum steel when heat-treated?

    <p>It is deep hardening, easily machined, and readily welded</p> Signup and view all the answers

    What is the primary advantage of using chrome-molybdenum steel in aircraft construction?

    <p>It provides high strength, toughness, and resistance to wear and fatigue</p> Signup and view all the answers

    What is the purpose of adding molybdenum to chromium steel?

    <p>To raise its ultimate strength without affecting ductility or workability</p> Signup and view all the answers

    What is a characteristic of Inconel, a nickel-chromium-iron alloy?

    <p>It is closely resembling stainless steel in appearance</p> Signup and view all the answers

    What is the carbon percentage range in high carbon steel?

    <p>0.50 to 1.05 percent</p> Signup and view all the answers

    What is the carbon content range of the series of chrome-molybdenum steel commonly used in aircraft construction?

    <p>0.25 to 0.55 percent</p> Signup and view all the answers

    What type of steel alloy contains chromium and molybdenum?

    <p>47xx steel</p> Signup and view all the answers

    What is a use of SAE 6150 steel?

    <p>Making springs</p> Signup and view all the answers

    What is a benefit of using chrome-molybdenum steel in welded structural parts and assemblies?

    <p>It is especially adaptable for welding</p> Signup and view all the answers

    What is the primary element added to steel to increase its hardness?

    <p>Carbon</p> Signup and view all the answers

    What is a characteristic of heat-treated SAE X4130 tube?

    <p>It is approximately four times as strong as an SAE 1025 tube of the same weight and size</p> Signup and view all the answers

    What type of steel is especially adaptable for machining or forging and where surface hardness is desirable?

    <p>Medium carbon steel</p> Signup and view all the answers

    Which type of steel alloy contains nickel and chromium?

    <p>33xx steel</p> Signup and view all the answers

    What type of steel is SAE 1035?

    <p>Medium carbon steel</p> Signup and view all the answers

    Which series of steel alloys contains manganese?

    <p>13xx steel</p> Signup and view all the answers

    Which type of steel alloy contains nickel, chromium, and molybdenum?

    <p>43xx steel</p> Signup and view all the answers

    What is the carbon percentage range in high carbon steel?

    <p>0.50 to 1.05 percent</p> Signup and view all the answers

    Which type of steel contains chromium and molybdenum?

    <p>Chromium Steel</p> Signup and view all the answers

    What is the primary element added to steel to increase its hardness?

    <p>Carbon</p> Signup and view all the answers

    Which type of steel is SAE 1035?

    <p>Medium Carbon Steel</p> Signup and view all the answers

    What type of steel contains nickel and chromium?

    <p>Chrome-nickel Steel</p> Signup and view all the answers

    Which type of steel has a carbon percentage range of 0.30 to 0.50 percent?

    <p>Medium Carbon Steel</p> Signup and view all the answers

    What type of steel is commonly used in rod ends and light forgings?

    <p>SAE 1035 Steel</p> Signup and view all the answers

    Which type of steel alloy contains manganese?

    <p>13xx Steel</p> Signup and view all the answers

    What is the primary characteristic of the spark stream in low carbon steel?

    <p>Long, straight shafts with few white sprigs</p> Signup and view all the answers

    What is the carbon percentage range in low carbon steel?

    <p>0.10 to 0.30 percent</p> Signup and view all the answers

    What is the characteristic of the spark stream in nickel steel?

    <p>Small white blocks of light within the main burst</p> Signup and view all the answers

    What is the equivalent SAE number range for low carbon steel?

    <p>1010 to 1030</p> Signup and view all the answers

    What is the use of low carbon steel in sheet form?

    <p>Secondary structural parts and clamps</p> Signup and view all the answers

    What is the characteristic of the spark stream in wrought iron?

    <p>Long shafts that are straw colored as they leave the stone and white at the end</p> Signup and view all the answers

    What is the characteristic of the spark stream in cast iron?

    <p>Red sparks that turn to a straw color</p> Signup and view all the answers

    What happens to the spark stream as the carbon content of the steel increases?

    <p>The number of sprigs along each shaft increases</p> Signup and view all the answers

    What is the percentage of carbon content in steel beyond which there is no increase in wear resistance?

    <p>0.85 percent</p> Signup and view all the answers

    What is the temperature range in which carbon steel must be cooled to harden?

    <p>Below 1,000 °F in less than 1 second</p> Signup and view all the answers

    Why can't pure iron, wrought iron, and extremely low carbon steels be appreciably hardened by heat treatment?

    <p>They contain no hardening element</p> Signup and view all the answers

    What is the transformation that occurs when cast iron is cooled rapidly?

    <p>Formation of white iron</p> Signup and view all the answers

    What is the primary factor that influences the critical points of heat treatment in steel?

    <p>Composition of the steel</p> Signup and view all the answers

    What is the result of hardening treatment on the ductility of steel?

    <p>It decreases the ductility of steel</p> Signup and view all the answers

    What is the temperature range in which austenite begins to transform into fine pearlite?

    <p>Below 1,000 °F</p> Signup and view all the answers

    What is the purpose of rapid cooling in the hardening treatment of steel?

    <p>To increase the hardness and strength of steel</p> Signup and view all the answers

    What happens when cast iron is cooled rapidly?

    <p>Forms white iron, which is hard and brittle</p> Signup and view all the answers

    What is the maximum carbon content percentage beyond which there is no increase in wear resistance?

    <p>0.85%</p> Signup and view all the answers

    What is the temperature range below which carbon steel must be cooled in less than 1 second to achieve hardening?

    <p>900-1000°F</p> Signup and view all the answers

    What is the primary reason why pure iron, wrought iron, and extremely low carbon steels cannot be hardened by heat treatment?

    <p>They contain no hardening element</p> Signup and view all the answers

    What happens when the carbon content of steel is increased beyond 0.85%?

    <p>There is no increase in wear resistance</p> Signup and view all the answers

    What is the primary purpose of the heat treatment process in steel?

    <p>To increase the hardness and strength of steel</p> Signup and view all the answers

    What is the result of cooling steel rapidly during the hardening process?

    <p>The formation of very fine carbide particles</p> Signup and view all the answers

    What is the critical point in the heat treatment of steel?

    <p>The temperature at which the carbide particles are dissolved in austenite</p> Signup and view all the answers

    What is the carbon percentage range in medium carbon steel?

    <p>0.30 to 0.50 percent</p> Signup and view all the answers

    What type of steel is SAE 1035?

    <p>Medium carbon steel</p> Signup and view all the answers

    What is the primary element added to steel to increase its hardness?

    <p>Carbon</p> Signup and view all the answers

    Which type of steel alloy contains chromium and molybdenum?

    <p>41xx Chromium steel</p> Signup and view all the answers

    What is the purpose of the chromium addition in steel alloys?

    <p>To increase corrosion resistance</p> Signup and view all the answers

    Which type of steel alloy has excellent corrosion resistance and high thermal and electrical conductivity?

    <p>Nickel steel</p> Signup and view all the answers

    What is the primary advantage of using chrome-nickel steel in aircraft applications?

    <p>Excellent corrosion resistance</p> Signup and view all the answers

    Which type of steel alloy is often used in critical aircraft structures such as engine mounts and wing components?

    <p>Chrome-nickel steel</p> Signup and view all the answers

    What is the characteristic of the spark stream produced by nickel steel during spark testing?

    <p>It contains small white blocks of light within the main burst</p> Signup and view all the answers

    Which type of steel contains carbon in percentages ranging from 0.10 to 0.30 percent?

    <p>Low carbon steel</p> Signup and view all the answers

    What is the characteristic of the spark stream produced by wrought iron during spark testing?

    <p>It produces long shafts that are straw colored as they leave the stone</p> Signup and view all the answers

    What is the characteristic of the spark stream produced by cast iron during spark testing?

    <p>It produces long shafts that are red as they leave the stone</p> Signup and view all the answers

    What is the characteristic of the spark stream produced by low carbon steel during spark testing?

    <p>It produces long, straight shafts having a few white sprigs</p> Signup and view all the answers

    What is the use of low carbon steel in sheet form?

    <p>For secondary structural parts and clamps</p> Signup and view all the answers

    What is the use of low carbon steel in tubular form?

    <p>For moderately stressed structural parts</p> Signup and view all the answers

    What is the range of SAE numbers for low carbon steel?

    <p>1010 to 1030</p> Signup and view all the answers

    Study Notes

    Aircraft Materials

    Aluminum Alloys

    • Widely used in aircraft construction due to high strength-to-weight ratio, corrosion resistance, and low cost
    • Common alloys:
      • 2024-T3: high strength, used in aircraft structures
      • 6061-T6: moderate strength, used in aircraft skin and fuselage
      • 7075-T6: high strength, used in aircraft landing gear and engine components

    Steel Alloys

    • Used in high-stress applications due to high strength, high fatigue resistance, and low cost
    • Common alloys:
      • 4130: chromium-molybdenum alloy, used in aircraft landing gear and engine components
      • 15-5PH: precipitation-hardening alloy, used in aircraft fasteners and fittings
      • 17-4PH: precipitation-hardening alloy, used in aircraft engine components and fasteners

    Composite Materials

    • Made from a combination of materials, such as carbon fibers, glass fibers, and polymers
    • Advantages:
      • High strength-to-weight ratio
      • Corrosion resistance
      • Low maintenance
    • Used in aircraft structures, such as:
      • Wings
      • Fuselage
      • Control surfaces
      • Engine components

    Ceramic Materials

    • Used in high-temperature applications due to high thermal resistance and low thermal conductivity
    • Advantages:
      • High temperature resistance
      • Corrosion resistance
      • Low thermal conductivity
    • Used in aircraft components, such as:
      • Heat shields
      • Engine components
      • Thermal protection systems

    Nanomaterials

    • Materials with structures or components on the nanoscale (typically 1-100 nm)
    • Advantages:
      • High strength-to-weight ratio
      • High thermal resistance
      • Corrosion resistance
    • Potential applications in aircraft materials:
      • Lightweight structural components
      • High-temperature resistant coatings
      • Self-healing materials

    Aircraft Welding

    • Techniques used to join aircraft materials, including:
      • Gas tungsten arc welding (GTAW)
      • Gas metal arc welding (GMAW)
      • Resistance welding
      • Friction stir welding
    • Important considerations:
      • Material compatibility
      • Weld joint design
      • Welding process control
      • Post-weld heat treatment

    Aircraft Materials

    Aluminum Alloys

    • Used in aircraft construction due to high strength-to-weight ratio, corrosion resistance, and low cost
    • Common alloys:
      • 2024-T3: high strength for aircraft structures
      • 6061-T6: moderate strength for aircraft skin and fuselage
      • 7075-T6: high strength for aircraft landing gear and engine components

    Steel Alloys

    • Used in high-stress applications due to high strength, high fatigue resistance, and low cost
    • Common alloys:
      • 4130: chromium-molybdenum alloy for aircraft landing gear and engine components
      • 15-5PH: precipitation-hardening alloy for aircraft fasteners and fittings
      • 17-4PH: precipitation-hardening alloy for aircraft engine components and fasteners

    Composite Materials

    • Combine materials like carbon fibers, glass fibers, and polymers for:
      • High strength-to-weight ratio
      • Corrosion resistance
      • Low maintenance
    • Used in aircraft structures:
      • Wings
      • Fuselage
      • Control surfaces
      • Engine components

    Ceramic Materials

    • Used in high-temperature applications due to:
      • High thermal resistance
      • Low thermal conductivity
    • Advantages:
      • Corrosion resistance
      • High temperature resistance
    • Used in aircraft components:
      • Heat shields
      • Engine components
      • Thermal protection systems

    Nanomaterials

    • Materials with structures or components on the nanoscale (1-100 nm)
    • Advantages:
      • High strength-to-weight ratio
      • High thermal resistance
      • Corrosion resistance
    • Potential applications:
      • Lightweight structural components
      • High-temperature resistant coatings
      • Self-healing materials

    Aircraft Welding

    • Techniques for joining aircraft materials:
      • Gas tungsten arc welding (GTAW)
      • Gas metal arc welding (GMAW)
      • Resistance welding
      • Friction stir welding
    • Important considerations:
      • Material compatibility
      • Weld joint design
      • Welding process control
      • Post-weld heat treatment

    Austempering

    • Increases strength and toughness of steel through a heat treatment process
    • Involves heating steel to a critical temperature, then quenching it in a molten salt bath or oil
    • Achieves a specific microstructure, resulting in high strength, toughness, and resistance to corrosion and fatigue

    Martensitic Steel

    • High-strength steel alloy with a minimum of 11.5% chromium
    • Known for high hardness, strength, and resistance to corrosion and wear
    • Used in high-stress applications such as landing gear, engine mounts, and fasteners
    • Can be heat-treated to achieve high strength-to-weight ratios

    Chromoly

    • High-strength, low-alloy steel containing chromium and molybdenum
    • Known for high strength, toughness, and resistance to corrosion and fatigue
    • Used in aircraft landing gear, axles, and other high-stress components
    • Can be heat-treated to achieve high strength-to-weight ratios

    High-strength Alloy

    • Steel alloy containing chromium, molybdenum, and nickel
    • Known for high strength, toughness, and resistance to corrosion and fatigue
    • Used in critical aircraft structures such as engine mounts, fasteners, and wing components
    • Can be heat-treated to achieve high strength-to-weight ratios

    Heat Treatment Processes

    Annealing

    • Heats steel to a critical temperature, then slowly cools it to relieve internal stresses
    • Achieves a specific microstructure

    Hardening

    • Heats steel to a critical temperature, then quenches it in oil or water
    • Achieves high hardness and strength

    Tempering

    • Heats steel to a specific temperature to reduce its hardness
    • Increases toughness

    Nitriding

    • Heats steel in a nitrogen atmosphere to achieve high surface hardness and wear resistance

    Aircraft Materials

    • Aluminum alloys are widely used in aircraft construction due to their high strength-to-weight ratio, corrosion resistance, and low cost
      • Common alloys include 2024-T3, 6061-T6, and 7075-T6, each with unique properties and applications

    Steel Alloys

    • Steel alloys are used in high-stress applications due to their high strength, high fatigue resistance, and low cost
      • Common alloys include 4130, 15-5PH, and 17-4PH, each with unique properties and applications

    Composite Materials

    • Composite materials are made from a combination of materials, such as carbon fibers, glass fibers, and polymers
      • Advantages include high strength-to-weight ratio, corrosion resistance, and low maintenance
      • Used in aircraft structures, such as wings, fuselage, control surfaces, and engine components

    Ceramic Materials

    • Ceramic materials are used in high-temperature applications due to their high thermal resistance and low thermal conductivity
      • Advantages include high temperature resistance, corrosion resistance, and low thermal conductivity
      • Used in aircraft components, such as heat shields, engine components, and thermal protection systems

    Nanomaterials

    • Nanomaterials have structures or components on the nanoscale (typically 1-100 nm)
      • Advantages include high strength-to-weight ratio, high thermal resistance, and corrosion resistance
      • Potential applications include lightweight structural components, high-temperature resistant coatings, and self-healing materials

    Aircraft Welding

    • Aircraft welding techniques include gas tungsten arc welding (GTAW), gas metal arc welding (GMAW), resistance welding, and friction stir welding
      • Important considerations include material compatibility, weld joint design, welding process control, and post-weld heat treatment

    Heat Treatment Processes

    • Austempering is a heat treatment process that increases strength and toughness in steel
    • Martensitic steel is a type of high-strength steel alloy that contains a minimum of 11.5% chromium
    • Chromoly is a type of high-strength, low-alloy steel that contains chromium and molybdenum
    • High-strength alloys contain a combination of elements such as chromium, molybdenum, and nickel
      • Each type of steel alloy has unique properties and applications
    • Heat treatment processes include annealing, hardening, tempering, austempering, and nitriding
      • Each process achieves a specific microstructure or property in steel alloys

    Alloying Elements and Composition

    • Aluminum alloys are classified into series based on their principal alloying element
    • 1000 series: 99% aluminum or higher, with iron and silicon as major impurities
    • 2000 series: Copper is the principal alloying element, with poor corrosion resistance unless clad
    • 3000 series: Manganese is the principal alloying element, generally non-heat treatable
    • 4000 series: Silicon is the principal alloying element, lowers melting temperature, and is used in welding and brazing
    • 5000 series: Magnesium is the principal alloying element, with good welding and corrosion-resistant characteristics
    • 6000 series: Silicon and magnesium form magnesium silicide, making alloys heat-treatable
    • 7000 series: Zinc is the principal alloying element, with high strength and heat-treatability when combined with magnesium and other elements

    Properties and Applications

    • 1000 series: Excellent corrosion resistance, high thermal and electrical conductivity, low mechanical properties, and excellent workability
    • 2000 series: Solution heat treatment, optimum properties equal to mild steel, but poor corrosion resistance unless clad
    • 3000 series: Moderate strength, good working characteristics, and high degree of resistance to corrosion
    • 4000 series: Limited heat treatment, used in welding and brazing
    • 5000 series: High temperatures or excessive cold working increase susceptibility to corrosion
    • 6000 series: Medium strength, good forming qualities, and corrosion-resistant characteristics
    • 7000 series: High strength, heat-treatable, and corrosion-resistant, with copper and chromium added

    Hardness Identification and Alloy Designation

    • Temper designation follows the alloy designation, separated by a dash (e.g., 7075-T6)
    • First digit in the alloy designation indicates the major alloying element:
      • 2xxx: Copper
      • 3xxx: Manganese
      • 4xxx: Silicon
      • 5xxx: Magnesium
      • 6xxx: Magnesium and silicon
      • 7xxx: Zinc
      • 8xxx: Other elements
    • Second digit in the alloy designation indicates alloy modifications
    • Last two digits in the alloy designation identify different alloys in the group

    Steel Properties

    • Strength, toughness, and resistance to wear and fatigue can be achieved through heat-treatment.
    • Chrome-vanadium with high carbon content is used for ball and roller bearings.
    • Molybdenum in small percentages is used in combination with chromium to form chrome-molybdenum steel, which has various uses in aircraft.

    Chrome-Molybdenum Steel

    • Raises the ultimate strength of steel without affecting ductility or workability.
    • Tough and wear resistant, and hardens throughout when heat-treated.
    • Especially adaptable for welding and used principally for welded structural parts and assemblies.
    • Has practically replaced carbon steel in the fabrication of fuselage tubing, engine mounts, landing gears, and other structural parts.

    Chrome-Molybdenum Steel in Aircraft Construction

    • Series containing 0.25 to 0.55 percent carbon, 0.15 to 0.25 percent molybdenum, and 0.50 to 1.10 percent chromium.
    • Deep hardening, easily machined, readily welded by either gas or electric methods, and adapted to high temperature service.

    Nickel Steels

    • Produced by combining nickel with carbon steel.
    • Steels containing from 3 to 3.75 percent nickel are commonly used.
    • Nickel increases the hardness, tensile strength, and elastic limit of steel without appreciably decreasing ductility.
    • Intensifies the hardening effect of heat treatment.

    Nickel Steels in Aircraft

    • SAE 2330 steel is used extensively for aircraft parts, such as bolts, terminals, keys, clevises, and pins.

    Chromium Steel

    • High in hardness, strength, and corrosion-resistant properties.
    • Particularly adaptable for heat-treated forgings, which require greater toughness and strength than may be obtained in plain carbon steel.
    • Used for articles such as the balls and rollers of antifriction bearings.

    Stainless Steel

    • The corrosion-resistant metal.
    • The anticorrosive degree is determined by the surface condition of the metal, as well as by the composition, temperature, and concentration of the corrosive agent.
    • The principal alloy of stainless steel is chromium.
    • 18-8 steel is commonly used in aircraft construction due to its high strength, corrosion resistance, and ability to be rolled, drawn, bent, or formed to any shape.

    Stainless Steel Applications

    • Fabrication of exhaust collectors, stacks, and manifolds, structural and machined parts, springs, castings, tie rods, and control cables.

    Chrome-Vanadium Steels

    • Made of approximately 18 percent vanadium and about 1 percent chromium.
    • Steel containing carbon in percentages ranging from 0.30 to 0.50 percent is classed as medium carbon steel.
    • SAE 1035 steel is used for certain rod ends and light forgings.

    High Carbon Steel

    • Steel containing carbon in percentages ranging from 0.50 to 1.05 percent.
    • The addition of other elements in varying quantities adds to the hardness of this steel.

    Series Designation Types

    • 10xx: Non-sulfurized carbon steels
    • 11xx: Resulfurized carbon steels (free machining)
    • 12xx: Rephosphorized and resulfurized carbon steels (free machining)
    • 13xx: Manganese
    • 23xx: Nickel 3.50%
    • 25xx: Nickel 5.00%
    • 31xx: Nickel 1.25%, chromium 0.65%
    • 33xx: Nickel 3.50%, chromium 1.55%
    • 40xx: Molybdenum 0.20 or 0.25%
    • 41xx: Chromium 0.50% or 0.95%, molybdenum 0.12 or 0.20%
    • 43xx: Nickel 1.80%, chromium 0.50% or 0.80%, molybdenum 0.25%
    • 44xx: Molybdenum 0.40%
    • 45xx: Molybdenum 0.52%
    • 46xx: Nickel 1.80%, molybdenum 0.25%
    • 47xx: Nickel 1.05%, chromium 0.45%, molybdenum 0.20 or 0.35%
    • 48xx: Nickel 3.50%, molybdenum 0.25%
    • 50xx: Chromium 0.25, or 0.40 or 0.50%
    • 50xxx: Carbon 1.00%, chromium 0.50%
    • 51xx: Chromium 0.80, 0.90, 0.95 or 1.00%
    • 51xxx: Carbon 1.00%, chromium 1.05%
    • 52xxx: Carbon 1.00%, chromium 1.45%
    • 61xx: Chromium 0.60, 0.80, 0.95%, vanadium 0.12%, 0.10% min., or 0.15% min.
    • 81xx: Nickel 0.30%, chromium 0.40%, molybdenum 0.12%
    • 86xx: Nickel 0.55%, chromium 0.50%, molybdenum 0.20%
    • 87xx: Nickel 0.55%, chromium 0.05%, molybdenum 0.25%
    • 88xx: Nickel 0.55%, chromium 0.05%, molybdenum 0.35%
    • 92xx: Manganese 0.85%, silicon 2.00%, chromium 0 or 0.35%
    • 93xx: Nickel 3.25%, chromium 1.20%, molybdenum 0.12%
    • 94xx: Nickel 0.45%, chromium 0.40%, molybdenum 0.12%
    • 98xx: Nickel 1.00%, chromium 0.80%, molybdenum 0.25%

    Monel

    • Adaptable to casting and hot or cold working, and can be successfully welded.
    • Has working properties like those of steel.
    • When forged and annealed, it has a tensile strength of 80,000 psi.
    • Can be increased by cold working to 125,000 psi.

    K-Monel

    • A nonferrous alloy containing mainly nickel, copper, and aluminum.
    • Corrosion resistant and capable of being hardened by heat treatment.
    • Nonmagnetic at all temperatures.

    Nickel and Nickel Alloys

    • Monel and Inconel are the two nickel alloys used in aircraft.
    • Monel contains about 68 percent nickel and 29 percent copper, plus small amounts of iron and manganese.
    • Inconel alloys of nickel produce a high strength, high temperature alloy containing approximately 80 percent nickel, 14 percent chromium, and small amounts of iron and other elements.
    • Inconel and stainless steel are similar in appearance and are frequently found in the same areas of the engine.

    Substitution of Aircraft Metals

    • Four requirements must be kept in mind when selecting substitute metals: maintaining the original strength of the structure, maintaining contour or aerodynamic smoothness, maintaining original weight, and maintaining the original corrosion-resistant properties of the metal.

    Metalworking Processes

    • Three methods of metalworking: hot working, cold working, and extruding.
    • The method used depends on the metal involved and the part required.

    Hot Working

    • Almost all steel is hot worked from the ingot into some form from which it is either hot or cold worked to the finished shape.

    Aluminum Bronzes

    • Wrought aluminum bronzes are almost as strong and ductile as medium carbon steel, and they possess a high degree of resistance to corrosion.
    • Readily forged, hot or cold rolled, and many react to heat treatment.
    • These copper base alloys contain up to 16 percent of aluminum (usually 5 to 11 percent), to which other metals, such as iron, nickel, or manganese, may be added.

    Cast Aluminum Bronzes

    • Have high strength combined with ductility and are resistant to corrosion, shock, and fatigue.
    • Used in bearings and pump parts.

    Manganese Bronze

    • An exceptionally high strength, tough, corrosion-resistant copper zinc alloy containing aluminum, manganese, iron, and occasionally, nickel or tin.
    • Can be formed, extruded, drawn, or rolled to any desired shape.
    • In rod form, it is generally used for machined parts for aircraft landing gears and brackets.

    Silicon Bronze

    • A more recent development composed of about 95 percent copper, 3 percent silicon, and 2 percent manganese, zinc, iron, tin, and aluminum.
    • Has high strength and great corrosion resistance.

    Steel Properties and Uses

    • Heat-treated steel has strength, toughness, and resistance to wear and fatigue.
    • Chromium-vanadium steel (SAE 6150) is used for making springs; chrome-vanadium with high carbon content (SAE 6195) is used for ball and roller bearings.
    • Molybdenum in small percentages is used in combination with chromium to form chrome-molybdenum steel, which has various uses in aircraft.

    Chrome-Molybdenum Steel

    • Raises the ultimate strength of steel without affecting ductility or workability.
    • Tough and wear-resistant, harden throughout when heat-treated.
    • Especially adaptable for welding, used principally for welded structural parts and assemblies.
    • Heat-treated SAE X4130 tube is approximately four times as strong as an SAE 1025 tube of the same weight and size.

    Inconel

    • Nickel-chromium-iron alloy closely resembling stainless steel (corrosion-resistant steel (CRES)) in appearance.
    • Used in aircraft exhaust systems.

    Nickel Steels

    • Produced by combining nickel with carbon steel.
    • Nickels increase the hardness, tensile strength, and elastic limit of steel without appreciably decreasing ductility.
    • Intensify the hardening effect of heat treatment.
    • SAE 2330 steel is used extensively for aircraft parts, such as bolts, terminals, keys, clevises, and pins.

    Chromium Steel

    • High in hardness, strength, and corrosion-resistant properties.
    • Particularly adaptable for heat-treated forgings, which require greater toughness and strength than plain carbon steel.

    Stainless Steel (Chrome-Nickel Steel)

    • Corrosion-resistant metal with a principal alloy of chromium.
    • The corrosion-resistant steel most often used in aircraft construction is known as 18-8 steel (18% chromium and 8% nickel).
    • Cold working may increase its strength.
    • Can be used for almost any part of an aircraft, such as exhaust collectors, stacks, and manifolds.

    Steel Designation Types

    • 10xx: Non-sulfurized carbon steels
    • 11xx: Resulfurized carbon steels (free machining)
    • 12xx: Rephosphorized and resulfurized carbon steels (free machining)
    • 13xx: Manganese
    • Other series designations have varying percentages of nickel, chromium, molybdenum, and carbon.

    Carbon Steel

    • Steel containing carbon in percentages ranging from 0.30 to 0.50% is classed as medium carbon steel.
    • Steel containing carbon in percentages ranging from 0.50 to 1.05% is classed as high carbon steel.

    Steel Properties and Uses

    • Heat-treated steel has strength, toughness, and resistance to wear and fatigue.
    • Chromium-vanadium steel (SAE 6150) is used for making springs; chrome-vanadium with high carbon content (SAE 6195) is used for ball and roller bearings.
    • Molybdenum in small percentages is used in combination with chromium to form chrome-molybdenum steel, which has various uses in aircraft.

    Chrome-Molybdenum Steel

    • Raises the ultimate strength of steel without affecting ductility or workability.
    • Tough and wear-resistant, harden throughout when heat-treated.
    • Especially adaptable for welding, used principally for welded structural parts and assemblies.
    • Heat-treated SAE X4130 tube is approximately four times as strong as an SAE 1025 tube of the same weight and size.

    Inconel

    • Nickel-chromium-iron alloy closely resembling stainless steel (corrosion-resistant steel (CRES)) in appearance.
    • Used in aircraft exhaust systems.

    Nickel Steels

    • Produced by combining nickel with carbon steel.
    • Nickels increase the hardness, tensile strength, and elastic limit of steel without appreciably decreasing ductility.
    • Intensify the hardening effect of heat treatment.
    • SAE 2330 steel is used extensively for aircraft parts, such as bolts, terminals, keys, clevises, and pins.

    Chromium Steel

    • High in hardness, strength, and corrosion-resistant properties.
    • Particularly adaptable for heat-treated forgings, which require greater toughness and strength than plain carbon steel.

    Stainless Steel (Chrome-Nickel Steel)

    • Corrosion-resistant metal with a principal alloy of chromium.
    • The corrosion-resistant steel most often used in aircraft construction is known as 18-8 steel (18% chromium and 8% nickel).
    • Cold working may increase its strength.
    • Can be used for almost any part of an aircraft, such as exhaust collectors, stacks, and manifolds.

    Steel Designation Types

    • 10xx: Non-sulfurized carbon steels
    • 11xx: Resulfurized carbon steels (free machining)
    • 12xx: Rephosphorized and resulfurized carbon steels (free machining)
    • 13xx: Manganese
    • Other series designations have varying percentages of nickel, chromium, molybdenum, and carbon.

    Carbon Steel

    • Steel containing carbon in percentages ranging from 0.30 to 0.50% is classed as medium carbon steel.
    • Steel containing carbon in percentages ranging from 0.50 to 1.05% is classed as high carbon steel.

    Steel Properties and Uses

    • Heat-treated steel has strength, toughness, and resistance to wear and fatigue.
    • Chromium-vanadium steel (SAE 6150) is used for making springs; chrome-vanadium with high carbon content (SAE 6195) is used for ball and roller bearings.
    • Molybdenum in small percentages is used in combination with chromium to form chrome-molybdenum steel, which has various uses in aircraft.

    Chrome-Molybdenum Steel

    • Raises the ultimate strength of steel without affecting ductility or workability.
    • Tough and wear-resistant, harden throughout when heat-treated.
    • Especially adaptable for welding, used principally for welded structural parts and assemblies.
    • Heat-treated SAE X4130 tube is approximately four times as strong as an SAE 1025 tube of the same weight and size.

    Inconel

    • Nickel-chromium-iron alloy closely resembling stainless steel (corrosion-resistant steel (CRES)) in appearance.
    • Used in aircraft exhaust systems.

    Nickel Steels

    • Produced by combining nickel with carbon steel.
    • Nickels increase the hardness, tensile strength, and elastic limit of steel without appreciably decreasing ductility.
    • Intensify the hardening effect of heat treatment.
    • SAE 2330 steel is used extensively for aircraft parts, such as bolts, terminals, keys, clevises, and pins.

    Chromium Steel

    • High in hardness, strength, and corrosion-resistant properties.
    • Particularly adaptable for heat-treated forgings, which require greater toughness and strength than plain carbon steel.

    Stainless Steel (Chrome-Nickel Steel)

    • Corrosion-resistant metal with a principal alloy of chromium.
    • The corrosion-resistant steel most often used in aircraft construction is known as 18-8 steel (18% chromium and 8% nickel).
    • Cold working may increase its strength.
    • Can be used for almost any part of an aircraft, such as exhaust collectors, stacks, and manifolds.

    Steel Designation Types

    • 10xx: Non-sulfurized carbon steels
    • 11xx: Resulfurized carbon steels (free machining)
    • 12xx: Rephosphorized and resulfurized carbon steels (free machining)
    • 13xx: Manganese
    • Other series designations have varying percentages of nickel, chromium, molybdenum, and carbon.

    Carbon Steel

    • Steel containing carbon in percentages ranging from 0.30 to 0.50% is classed as medium carbon steel.
    • Steel containing carbon in percentages ranging from 0.50 to 1.05% is classed as high carbon steel.

    Steel Classification

    • Steel containing 0.30-0.50% carbon is classified as medium carbon steel, suitable for machining or forging and requiring surface hardness.
    • Steel containing 0.50-1.05% carbon is classified as high carbon steel, with added elements increasing hardness.

    Series Designation Types

    • 10xx: Non-sulfurized carbon steels
    • 11xx: Resulfurized carbon steels (free machining)
    • 12xx: Rephosphorized and resulfurized carbon steels (free machining)
    • 13xx: Manganese 1.75%
    • 23xx: Nickel 3.50%
    • 25xx: Nickel 5.00%
    • 31xx: Nickel 1.25%, chromium 0.65%
    • 33xx: Nickel 3.50%, chromium 1.55%
    • 40xx: Molybdenum 0.20 or 0.25%
    • 41xx: Chromium 0.50% or 0.95%, molybdenum 0.12 or 0.20%
    • 43xx: Nickel 1.80%, chromium 0.5 or 0.80%, molybdenum 0.25%
    • 44xx: Molybdenum 0.40%
    • 45xx: Molybdenum 0.52%
    • 46xx: Nickel 1.80%, molybdenum 0.25%
    • 47xx: Nickel 1.05%, chromium 0.45%, molybdenum 0.20 or 0.35%
    • 48xx: Nickel 3.50%, molybdenum 0.25%
    • 50xx: Chromium 0.25, 0.40, or 0.50%
    • 51xx: Chromium 0.80, 0.90, 0.95, or 1.00%
    • 61xx: Chromium 0.60, 0.80, 0.95%, vanadium 0.12%, 0.10% min., or 0.15% min.
    • 81xx: Nickel 0.30%, chromium 0.40%, molybdenum 0.12%
    • 86xx: Nickel 0.55%, chromium 0.50%, molybdenum 0.20%
    • 87xx: Nickel 0.55%, chromium 0.05%, molybdenum 0.25%
    • 88xx: Nickel 0.55%, chromium 0.05%, molybdenum 0.35%
    • 92xx: Manganese 0.85%, silicon 2.00%, chromium 0 or 0.35%
    • 93xx: Nickel 3.25%, chromium 1.20%, molybdenum 0.12%
    • 94xx: Nickel 0.45%, chromium 0.40%, molybdenum 0.12%
    • 98xx: Nickel 1.00%, chromium 0.80%, molybdenum 0.25%

    Spark Testing

    • Spark testing is a method of identifying ferrous metals by their spark characteristics when held against a revolving grinding stone.
    • Each ferrous metal has its own peculiar spark characteristics.
    • Spark streams vary from a few tiny shafts to a shower of sparks several feet in length.

    Low Carbon Steel

    • Steel containing 0.10-0.30% carbon is classified as low carbon steel.
    • Equivalent SAE numbers range from 1010 to 1030.
    • Low carbon steel is used for making items such as safety wire, nuts, cable bushings, and threaded rod ends.
    • It is also used for secondary structural parts and clamps in sheet form and moderately stressed structural parts in tubular form.

    Hardening

    • Pure iron, wrought iron, and extremely low carbon steels cannot be appreciably hardened by heat treatment.
    • Cast iron can be hardened, but its heat treatment is limited.
    • In plain carbon steel, the maximum hardness depends almost entirely on the carbon content of the steel.
    • When the carbon content is increased beyond 0.85%, there is no increase in wear resistance.
    • Hardening treatment consists of heating the steel to a temperature just above the upper critical point, soaking, and then cooling rapidly by plunging into oil, water, or brine.

    Steel Classification

    • Steel containing 0.30-0.50% carbon is classified as medium carbon steel, suitable for machining or forging and requiring surface hardness.
    • Steel containing 0.50-1.05% carbon is classified as high carbon steel, with added elements increasing hardness.

    Series Designation Types

    • 10xx: Non-sulfurized carbon steels
    • 11xx: Resulfurized carbon steels (free machining)
    • 12xx: Rephosphorized and resulfurized carbon steels (free machining)
    • 13xx: Manganese 1.75%
    • 23xx: Nickel 3.50%
    • 25xx: Nickel 5.00%
    • 31xx: Nickel 1.25%, chromium 0.65%
    • 33xx: Nickel 3.50%, chromium 1.55%
    • 40xx: Molybdenum 0.20 or 0.25%
    • 41xx: Chromium 0.50% or 0.95%, molybdenum 0.12 or 0.20%
    • 43xx: Nickel 1.80%, chromium 0.5 or 0.80%, molybdenum 0.25%
    • 44xx: Molybdenum 0.40%
    • 45xx: Molybdenum 0.52%
    • 46xx: Nickel 1.80%, molybdenum 0.25%
    • 47xx: Nickel 1.05%, chromium 0.45%, molybdenum 0.20 or 0.35%
    • 48xx: Nickel 3.50%, molybdenum 0.25%
    • 50xx: Chromium 0.25, 0.40, or 0.50%
    • 51xx: Chromium 0.80, 0.90, 0.95, or 1.00%
    • 61xx: Chromium 0.60, 0.80, 0.95%, vanadium 0.12%, 0.10% min., or 0.15% min.
    • 81xx: Nickel 0.30%, chromium 0.40%, molybdenum 0.12%
    • 86xx: Nickel 0.55%, chromium 0.50%, molybdenum 0.20%
    • 87xx: Nickel 0.55%, chromium 0.05%, molybdenum 0.25%
    • 88xx: Nickel 0.55%, chromium 0.05%, molybdenum 0.35%
    • 92xx: Manganese 0.85%, silicon 2.00%, chromium 0 or 0.35%
    • 93xx: Nickel 3.25%, chromium 1.20%, molybdenum 0.12%
    • 94xx: Nickel 0.45%, chromium 0.40%, molybdenum 0.12%
    • 98xx: Nickel 1.00%, chromium 0.80%, molybdenum 0.25%

    Spark Testing

    • Spark testing is a method of identifying ferrous metals by their spark characteristics when held against a revolving grinding stone.
    • Each ferrous metal has its own peculiar spark characteristics.
    • Spark streams vary from a few tiny shafts to a shower of sparks several feet in length.

    Low Carbon Steel

    • Steel containing 0.10-0.30% carbon is classified as low carbon steel.
    • Equivalent SAE numbers range from 1010 to 1030.
    • Low carbon steel is used for making items such as safety wire, nuts, cable bushings, and threaded rod ends.
    • It is also used for secondary structural parts and clamps in sheet form and moderately stressed structural parts in tubular form.

    Hardening

    • Pure iron, wrought iron, and extremely low carbon steels cannot be appreciably hardened by heat treatment.
    • Cast iron can be hardened, but its heat treatment is limited.
    • In plain carbon steel, the maximum hardness depends almost entirely on the carbon content of the steel.
    • When the carbon content is increased beyond 0.85%, there is no increase in wear resistance.
    • Hardening treatment consists of heating the steel to a temperature just above the upper critical point, soaking, and then cooling rapidly by plunging into oil, water, or brine.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Properties of Metals.docx

    Description

    This quiz covers the different types of materials used in aircraft construction, including aluminum alloys and steel alloys, their properties, and applications.

    More Like This

    Aluminum in Aircraft Manufacturing Quiz
    10 questions

    Aluminum in Aircraft Manufacturing Quiz

    EnergyEfficientTan avatar
    EnergyEfficientTan
    Aircraft Repair and Maintenance Quiz
    24 questions

    Aircraft Repair and Maintenance Quiz

    UnforgettableFeministArt8572 avatar
    UnforgettableFeministArt8572
    Aircraft Dope and Thinner Identification
    16 questions

    Aircraft Dope and Thinner Identification

    InvigoratingThorium avatar
    InvigoratingThorium
    Aircraft Structure Quiz Reviewer
    9 questions

    Aircraft Structure Quiz Reviewer

    SweepingXylophone avatar
    SweepingXylophone
    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser