Non-Ferrous Metal Materials PDF
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Uploaded by SuitableAntigorite278
Malaysian Institute of Aviation Technology
2024
EASA
M. Azlan Shafie
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Summary
This document is a set of lecture notes on non-ferrous metals, including information on their properties, applications in aircraft, and various alloying elements. The document is suitable for professionals in the aviation industry.
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EASA B1.1 : MODULE 6.2 NON-FERROUS METAL 12 October 2024 INTRODUCTION Non ferrous metals and alloys cover a wide range of materials; The common metals such as aluminum, copper, and magnesium High-strength...
EASA B1.1 : MODULE 6.2 NON-FERROUS METAL 12 October 2024 INTRODUCTION Non ferrous metals and alloys cover a wide range of materials; The common metals such as aluminum, copper, and magnesium High-strength high-temperature alloys, such as tungsten, tantalum, and molybdenum - Molybdenum does not occur naturally as a free metal on Earth; it is found only in various oxidation states in minerals. The free element, a silvery metal with a gray cast, has the sixth-highest melting point of any element. It readily forms hard, stable carbides in alloys, and for this reason most of world production of the element (about 80%) is used in steel alloys, including high strength alloys and super alloys. All of the above are classified as Non-Ferrous Metal Prepared By: M.Azlan Shafie Properties of Non-Ferrous Metals Generally, non-ferrous metals are more expensive than ferrous metals, but it has important applications because of properties such as: corrosion resistance high thermal and electrical conductivity low density ease of fabrication. Prepared By: M.Azlan Shafie Common Examples of Non-Ferrous Metals used in Aircraft Typical examples of the applications of non ferrous metals and alloys are: i. Aluminum for aircraft bodies ii. Copper wire for electricity iii. Tantalum for rocket engines iv. Titanium for jet engine turbine blades. v. Nickel and it’s alloys vi. Magnesium and it’s alloys Prepared By: M.Azlan Shafie Tantalum ~ A greyish silver, heavy, and very hard metal. When pure, it is ductile and can be drawn into fine wire, which can be used as a filament for evaporating metals such as aluminium. Tantalum is almost completely immune to chemical attack at temperatures below 150°C, and is attacked only by hydrofluoric acid, acidic solutions containing the fluoride ion, and free sulphur trioxide. The element has a melting point exceeded only by tungsten and rhenium. Prepared By: M.Azlan Shafie Light Alloys Prepared By: M.Azlan Shafie Light Alloys An alloy is a mixture of two or more metal alloy. Base metal Small percentage It consist of of other material e.g. Aluminum e.g. copper,zinc Alloy is used to enhanced properties of the basic metal such as: Corrosion resistant Tensile strength Etc Alloy form as listed in the table 2.1 showing their principal alloying metal and their effects. Prepared By: M.Azlan Shafie Table 2.1: Principle alloying metal and their effect Prepared By: M.Azlan Shafie Light Alloys Numerous other metallic elements are added in varying amounts to improve the properties or provide special effects. The list is shown in table 2.2 Additional Notes: Aluminum, magnesium, titanium, and beryllium are classified as light metals because their density is much less that of steel Prepared By: M.Azlan Shafie Table 2.2: Other metallic elements and their effect Prepared By: M.Azlan Shafie ALUMINIUM Pure aluminum has a low strength and is not suitable as a structural material. But it is used as a corrosion resisting material in the clad alloys. There are two main classes of aluminum alloy: Wrought alloys Cast alloys Most aircraft part are wrought alloys Prepared By: M.Azlan Shafie WROUGHT ALUMINIUM ALLOY Manganese Metals that are used as the principal alloying Silicon Zinc elements in wrought aluminum alloy Magnesium Prepared By: M.Azlan Shafie Bauxite is largely aluminium oxide mixed with impurities These impurities are An electrolytic removed by a process is used to chemical process obtain aluminium ALUMINIUM leaving the pure from the pure oxide aluminium oxide - alumina Prepared By: M.Azlan Shafie Bauxite (Aluminium ore) Heat equivalent to 4 tons Caustic soda 3 CWT 2 tons of coal Production of ALUMINA 2 tons (Aluminium Oxide ) Electricity 18,000 kwh Cryolite Carbon anodes Aluminium 1 ton Prepared By: M.Azlan Shafie Aluminium is manufactured to a high degree of purity in the electrolytic process. Its excellent corrosion resistance in oxidizing atmosphere is due to the film of oxide which forms on the surface. However, the strength of pure aluminium is low. So, it is alloyed with various other elements. The alloys have poorer corrosion resistance than pure aluminium, so the aluminium alloys are coated with pure aluminium called ALCLAD. Prepared By: M.Azlan Shafie ALCLAD ALUMINIUM The terms “Alclad and Pureclad” are used to designate sheets that consist of an aluminium alloy core coated with a layer of pure aluminium to a depth of approximately 5 ½ percent on each side. The pure aluminium coating affords a dual protection for the core, preventing contact with any corrosive agents, and protecting the core electrolytically by preventing any attack caused by scratching or from other abrasion. Aluminium Aluminium Alloy Core Protective Coating Prepared By: M.Azlan Shafie Three basic reasons for heat treating aluminium alloys are to : *Increase their strength *Improve their corrosion resistance *Improve their workability Increased strength and improved resistance to corrosion are achieved by : 1-Solution treatment followed by natural age hardening 2-Precipitation treatment which is applied to specific materials which have been previously solution treated. 3- This process is commonly known as artificial ageing To improve workability, the annealing process is applied Prepared By: M.Azlan Shafie HEAT TREATMENT OF ALUMINIUM ALLOYS Solution treatment Annealing Precipitation treatment (artificially aging) Prepared By: M.Azlan Shafie Solution Heat Treatment Solution heat treatment consist of heating the material to a prescribed temperature below the melting point generally in the temperature range 4950 C + 100 C depending on material specification. Precipitation Heat Treatment The process of artificially aging an alloy after heat treating to increase its strength The alloy is heated to a specific temperature for several hours. Followed by slowly cooling in air. Prepared By: M.Azlan Shafie Cold working of Solution Heat Treated Material When solution heat treated material has to be manipulated, it is desirable that the work be completed within two hours of quenching (Otherwise it will start to precipitate and hardens) - naturally aged Natural ageing can be suspended by storing the material at low temperature – immediately after solution treatment. Clad sheet should be heat treated a maximum of three times. Prepared By: M.Azlan Shafie The solution treated material should be stored in a refrigerator immediately following solution treatment and maintained at a suitable temperature Any manipulation required must be completed within two hours of the material being removed from refrigeration. The natural ageing process of aluminium alloys can be Suspended by refrigeration Should the time allowed for manipulation elapse or in the case on expiry of the maximum storage period ……….. ………………. further heat treatment will be necessary. Prepared By: M.Azlan Shafie Non Heat treatable alloys.( Strain Harden Alloy) These alloys contain alloying constituents that remain in solid solution or are insoluble at all temperatures. In addition to alloying, the strength can be increased by cold working (strain hardening ) Heat treatable alloys Certain alloys are susceptible to heat treatment making them still stronger These alloys contain alloying constituents that have increased solid solubility at elevated temperatures. Heat treatable alloys contain copper, magnesium or zinc as the principle alloying element. Prepared By: M.Azlan Shafie The annealing process softens the materials for manipulation purposes The annealing process consists of heating the material to a specific temperature followed by cooling in air at room temperature. The process normally calls for a temperature about 1000 C to 2000 C below that specified for solution treatment. The soaking period for all gauges of sheet material is usually about 1 hour. Prepared By: M.Azlan Shafie On completion of each heat treatment process, the material should be marked with the appropriate symbol. Numbering System For Aluminium Alloys The designation numbers consists essentially of four figures, each figure having it's own significance. The first digit represents the main alloying elements as shown in the table 2.3. Prepared By: M.Azlan Shafie SERIES ELEMENTS MIXTURE 1XXX PURE ALUMINUM (OVER 99% PURE) 2XXX COPPER 3XXX MANGANESE 4XXX SILICON 5XXX MAGNESIUM 6XXX MAGNESIUM AND SILICON 7XXX ZINC 8XXX SPECIAL ALLOYING ELEMENTS 9XXX UNUSED SERIES Table 2.3: Designations for Wrought Aluminum Alloy Groups Prepared By: M.Azlan Shafie The four-digit designation for an alloy is usually followed by a letter separated from the main number by a dash. E.g. 2024-T3 This letter indicates the condition of alloy: e.g. annealed, strain hardened, heat-treated etc. the standard letters are as Table 2.4 next page. Prepared By: M.Azlan Shafie F – As Fabricated O – Annealed (Wrought products only) H – Strain Hardened W – Solution heat treated to an unstable temper T3 – Heat Treated then cold worked T4 – Heat treated then naturally aged T6 – Heat treated then artificially aged Table 2.4 : Temper Designations for Heat Treatable Alloys Prepared By: M.Azlan Shafie The letter ‘H’ applies only to strain hardening alloys. Usually the letter ‘H’ is followed by two digits: e.g: 5056 - H36 The first letter indicates the method of hardening The second letter indicates the degree of hardening obtained. Letter ‘H’ Description H1x Strain hardened only H2x Strain hardened then partially annealed H3x Strain hardened then stabilised Hx2 Quarter hard Hx4 Half hard Hx6 Three quarters hard Hx8 Fully hard Prepared By: M.Azlan Shafie Example: 5056-H 36 is an aluminum magnesium alloy strain hardened and stabilized to three quarters full hardness. That is, it is three quarters of the way between the annealed state and the fully hardened state. Prepared By: M.Azlan Shafie Copper is the principle These alloys require solution alloying element in this heat treatment to obtain group optimum properties. Usually clad with high purity alloys. Can be subject to intergranular corrosion. 2000 SERIES Artificial ageing is employed Most common in this group to further increase the Is the 2024 mechanical properties. Prepared By: M.Azlan Shafie Used in airframe structures Copper and chromium are and for highly stressed parts also added in small quantities. 7000 SERIES Most common in this group is the 7075 Zinc is the major alloying element in this group and when coupled with a small percentage of magnesium results in heat treatable alloys of very high strength. Prepared By: M.Azlan Shafie Nickel is the chief constituent of a number of non-ferrous alloys which are used in special applications in aircraft work. The main feature common to all of these alloys is their good corrosion resistance. Monel Nimonic Nickel and Nickel Alloys Inconel Inconel “X” “K” Monel Prepared By: M.Azlan Shafie Copper and it’s alloys Copper, brass and bronze have important specialized applications in aircraft, such as bearings, fuel and oil lines and electrical wiring contacts. COPPER AND ITS ALLOYS - Reddish brown in colour. - Good conductor of heat and electricity. - Malleably and Ductile. Can be shaped by rolling, drawing, forging and pressing.copper is used to make electrical cables and parts for electrical equipments. Prepared By: M.Azlan Shafie BRASS Copper based alloys containing up to 45% zinc and sometimes small amount of other metals such as tin, aluminium, lead, manganese, these additions increase the tensile strength and resistance corrosion. It is used in manufacture of instrument mechanism, bellows assemblies and pitot head. BRONZE Copper based alloy containing up to 18% tin with small amount of phosphorus, zinc or lead. It is used in spring and instrument part, good elastic properties and also used in bearing and bushes. Titanium Titanium and its alloys are used widely in the aerospace industry because of its ………… *High strength Light weight Temperature resistance Corrosion resistance Hence, it is useful in the cooler section of gas turbines, engines, and for skin parts of aircraft which may be subjected to elevated temperatures damaging to aluminium alloys. Titanium can be sheared, drawn, pressed, machined and sawed. At high temperatures, titanium has high affinity for Precaution : oxygen and nitrogen. Prepared By: M.Azlan Shafie Properties of Magnesium Alloys Magnesium alloys are the lightest of the structural metal available It has excellent strength/ weight ratios. The greater proportion of magnesium alloy products have been castings. It is used extensively in aircraft construction in such applications as : ~ wheels ~ brake pedals ~ control columns ~ bell cranks ~ instrument panels Prepared By: M.Azlan Shafie Prepared By: M.Azlan Shafie Testing of Non-Ferrous Material Hardness Fatigue Strength Tensile Strength Impact Resistance Objectives: - At the end of this lesson, the student will be able to: - 1. List the methods of hardness test and how they are performed. 2. Identify the various methods of hardness test. Prepared By: M.Azlan Shafie Testing of Non-Ferrous Material Hardness Hardness Test of a material is carried out for the purpose of obtaining the material's hardness and also its strength. There are 3 methods of hardness test, namely: - i. Brinell Hardness Test ii. Rockwell Hardness Test iii. Vickers Hardness Test Prepared By: M.Azlan Shafie Brinell Hardness Test In this method, a hardness steel ball is pressed into the surface of the tested material at a specified load for specified period of time. The result taken is the measurement of ball indentation diameter, so determining the hardness of the material. Prepared By: M.Azlan Shafie Brinell Hardness Test Prepared By: M.Azlan Shafie Rockwell Hardness Test This method is very similar to Brinell Hardness Test and a diamond cone is used as the penetrator. Result from the depth of penetration of the diamond cone to the surface of the material will determine the hardness of the material. Prepared By: M.Azlan Shafie Rockwell Hardness Test Rockwell Scale Hardness Tester Indentation Prepared By: M.Azlan Shafie Vickers Hardness Test This test is similar to Rockwell Test except the penetrator is a square- based diamond pyramid shaped. The penetrator is forced onto the materials surface and measurement is taken on the cross-section of the square impression to determine the hardness of the material. Prepared By: M.Azlan Shafie Vickers Hardness Test Figure 1 Schematic principles of operation of Vickers hardness machine Figure 2 Vickers hardness test Prepared By: M.Azlan Shafie Tensile Test The tensile strength of a material is tested by: Clamping the material with specific dimension and thickness into the jaws of a tensile test machine and; Applied load gradually to pull the material apart until it breaks. The amount of load, which causes the material to break, is indicated on the testing machine. This will determine the tensile load of the material. Prepared By: M.Azlan Shafie Fatigue Test Fatigue test is normally required on parts, which are subjected to; rapid movement vibrations and load changes, which may occur billions of times. Fatigue life is the number of cycles a material can withstand at a specified stress without failure. Prepared By: M.Azlan Shafie Impact Test This test is conducted to measure the toughness of a material under shock loads. A pendulum strikes a sharp blow on a specimen, bending or breaking it. The impact strength is computed from the weight of the pendulum and the different between the rise of a free-swinging pendulum and the rise of a pendulum that has struck a specimen. The specimen is notched with specific dimension so as to give a clean break during the test. This test is most useful for comparing materials of similar strength and for evaluating the effects of heat treatment, processing variables or templates on the same type of material. Prepared By: M.Azlan Shafie Impact Test Prepared By: M.Azlan Shafie