Untitled Quiz

<p>Some materials will remain permanently deformed. (B)</p> Signup and view all the answers

<p>They can lead to brittle fracture in structures lacking stress relief. (B)</p> Signup and view all the answers

<p>Body-centered tetragonal (BCT) (D)</p> Signup and view all the answers

<p>The distortion of atoms and arrangement of dislocations. (C)</p> Signup and view all the answers

<p>They can lead to premature failure of critical components. (C)</p> Signup and view all the answers

<p>Residual stresses contributing to structural collapse. (A)</p> Signup and view all the answers

<p>Machining can lead to non-uniform plastic deformation. (D)</p> Signup and view all the answers

<p>Formation of a martensitic layer with sufficient hardness (A)</p> Signup and view all the answers

<p>925°C (C)</p> Signup and view all the answers

<p>They provide the fastest carburizing process (B)</p> Signup and view all the answers

<p>Develops a very hard case without quenching (B)</p> Signup and view all the answers

<p>Nitrogen (B)</p> Signup and view all the answers

<p>Coke or charcoal (C)</p> Signup and view all the answers

<p>No molecular size change occurs (B)</p> Signup and view all the answers

<p>36 hours (C)</p> Signup and view all the answers

<p>700 HV (D)</p> Signup and view all the answers

<p>It is the least sophisticated carburizing process (C)</p> Signup and view all the answers

<p>To diffuse nitrogen into the surface for hardness (D)</p> Signup and view all the answers

<p>450°C (B)</p> Signup and view all the answers

<p>Metallic coating type (A)</p> Signup and view all the answers

<p>Nitrogen stabilizes austenite (C)</p> Signup and view all the answers

<p>0.75 mm (A)</p> Signup and view all the answers

<p>900 to 955 °C (A)</p> Signup and view all the answers

<p>It avoids cyanide disposal issues (B)</p> Signup and view all the answers

<p>Heavy-duty gearing steel (A)</p> Signup and view all the answers

<p>Increases hardenability (D)</p> Signup and view all the answers

<p>Achieves full hardness with less distortion (A)</p> Signup and view all the answers

<p>To relieve internal stresses and augment material properties (B)</p> Signup and view all the answers

<p>Austenite (A)</p> Signup and view all the answers

<p>Rapid cooling from the austenitizing temperature (B)</p> Signup and view all the answers

<p>Annealing (B)</p> Signup and view all the answers

<p>Increases ductility and reduces hardness (B)</p> Signup and view all the answers

<p>Formation of globular carbides in a ferritic matrix (B)</p> Signup and view all the answers

<p>240°C (B)</p> Signup and view all the answers

<p>Hardness increases while ductility decreases (C)</p> Signup and view all the answers

<p>Transformation of retained austenite to ferrite and cementite (B)</p> Signup and view all the answers

<p>Delaying the cooling process just above the martensitic transformation (A)</p> Signup and view all the answers

<p>Refinement of grain structure and size (C)</p> Signup and view all the answers

<p>Resistance to brittle fracture (D)</p> Signup and view all the answers

<p>Heating to a temperature above A3 (D)</p> Signup and view all the answers

<p>Electroplating (C)</p> Signup and view all the answers

Stress is the internal force acting within a material in response to an external load, while strain is the resulting deformation or change in shape of the material.

Permanent change in shape of a material beyond its elastic limit.

Internal stresses that remain in a material after external loads are removed.

Change in the physical structure of a material, often involving a change in crystal structure or state (solid, liquid, gas).

A series of operations involved in cutting material into a desired shape and size.

A law stating that the stress in a material is proportional to the strain up to a certain limit. Stress = constant * Strain

A hard, brittle phase of steel formed by a rapid quenching process.

A phase/form of steel, typically soft and ductile.

Having different properties in different parts of the material. For example, a composite material.

Surface hardening of steel by introducing carbon.

Carburizing using a gas atmosphere containing carbon.

Carburizing using a salt bath containing carbon.

Carburizing using a solid pack containing carbon.

Surface hardening by introducing nitrogen.

Thickness of the hardened surface of carburized steel.

Temperature at which carbon diffuses into the steel.

Duration of the carburizing process, influencing case depth.

Liquid medium containing carbon and other elements for carburizing.

Improve hardness and add nitrogen to steel during liquid carburizing.

Solid material surrounding the component during solid carburizing, supplying carbon.

Process by which carbon atoms move from high concentration to low concentration into steel.

A thermochemical process of diffusing nitrogen into the surface of steels and cast irons.

The amount of nitrogen that can be absorbed by iron depends on the temperature.

A surface phase that forms when the nitrogen concentration in the iron-base alloy exceeds a certain limit.

A factor that increases the chance of the ε phase forming in nitriding.

A nitriding method using a controlled gas atmosphere in a furnace.

A modified carburizing process where nitrogen is added to the carburized case.

Carbonitriding is preferred over liquid cyaniding due to environmental concerns related to cyanide disposal.

This process creates a hard, wear-resistant case with a depth typically ranging from 0.075 mm to 0.75 mm.

Nitrogen increases the hardenability of steel by acting as an austenite stabilizer.

Starting with carburizing, followed by carbonitriding, and ending with quenching.

Steels with carbon content up to 0.25% for specific applications.

Combination of heating and cooling metal in the solid state to change its properties.

Relieves internal stresses from processes like cold-working, casting, welding, and hot-working while refining grain structure and enhancing mechanical, corrosion, and tribological properties.

Heat treatment applied to steel alloys of iron and carbon to control properties, avoiding the liquid phase.

Stable solid solution of carbon and other alloying elements in gamma-iron (γ-Fe).

BCC iron phase with limited carbon solubility.

Iron carbide (Fe3C) with 6.67 wt.% carbon.

Alternating lamellae of ferrite and cementite, formed by austenite decomposition.

Austenite transformed below Ms (240°C) temperature through a shear transformation.

Austenite transformation between pearlite and martensite formation temperatures.

Heating and cooling to soften metal, improve mechanical properties, and relieve stress.

Heating below the transformation range to relieve stresses from manufacturing.

Heating above the critical point followed by air cooling to refine grain structure.

Heating above the critical point for hypoeutectoid or above the lower critical temperature for hypereutectoid then slow cooling, allowing maximum softening.

Heating just below the transformation range then slow cooling to create globular carbides, improving formability and machinability.

Subcritical heating to soften materials after cold working to restore ductility.

Rapid cooling of metal from a high temperature to achieve hardness.

Reheating hardened steel below the critical temperature, decreasing hardness and increasing toughness.

Interrupted quench to a temperature above martensite formation followed by slow cooling to relieve quenching stresses.

Isothermal transformation to bainite below pearlite formation temperature, increasing ductility and strength.

Diffusion of carbon into the surface of a low-carbon steel part to increase surface hardness.