Steel Heat Treatment Techniques Quiz

<p>It must be soluble in the steel at the temperature used. (B)</p> Signup and view all the answers

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

<p>To stabilise the austenite phase at elevated temperatures (A)</p> Signup and view all the answers

<p>Neither method involves changing the chemical composition of steel (D)</p> Signup and view all the answers

<p>An increase in surface hardness. (D)</p> Signup and view all the answers

<p>820 ~ 840 ºC (B)</p> Signup and view all the answers

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

<p>It achieves surface hardening by rapid localized heating and quenching (A)</p> Signup and view all the answers

<p>0.3 ~ 0.6% C (B)</p> Signup and view all the answers

<p>To prevent the core of the material from being hardened. (A)</p> Signup and view all the answers

<p>By generating eddy currents within the steel. (C)</p> Signup and view all the answers

<p>It is spray-quenched. (D)</p> Signup and view all the answers

<p>It allows adjustment to the final hardness. (A)</p> Signup and view all the answers

<p>The surface volume increases and compressive stresses are induced. (D)</p> Signup and view all the answers

<p>They are typically carried out at temperatures below 600°C, reducing the risk of distortion. (C)</p> Signup and view all the answers

<p>It diffuses carbon into the steel surface above 880°C and uses quenching to form martensite. (B)</p> Signup and view all the answers

<p>To develop a hard martensitic case with a high carbon concentration. (D)</p> Signup and view all the answers

<p>It dissociates to supply atomic nitrogen that diffuses into the steel to form hard nitrides. (A)</p> Signup and view all the answers

<p>It involves heating components at around 500°C for 2-4 days. (A)</p> Signup and view all the answers

<p>Nitriding does not require quenching after the diffusion process, whereas carburizing does. (A)</p> Signup and view all the answers

<p>Austenite dissolves considerable amounts of carbon and nitrogen leading to greater dimensional changes. (D)</p> Signup and view all the answers

A heat treatment process that introduces carbon and nitrogen into the surface of steel, resulting in a hard and wear-resistant outer layer.

The process of rapidly heating the surface of steel to austenitize it, followed by quenching to harden the surface while keeping the core soft.

Involves heating the surface of the steel with high-frequency currents to induce eddy currents and rapid heating, followed by quenching.

The ability of nitrogen to stabilize the austenite phase in steel during heat treatment.

The slower transformation of austenite during carbonitriding, reducing the risk of distortion or warping of the steel.

The ability to adjust the relative amounts of carbon and nitrogen introduced during carbonitriding to control the properties of the hardened layer.

The carbon content in steel should be within the range of 0.3-0.6% for selective hardening.

The need for the steel to be heat-treated for core properties prior to selective hardening.

The process of diffusing carbon into the surface of steel to create a hard and wear-resistant layer.

Carburising involves heating steel above 880°C, usually to over 925°C, followed by quenching to create a martensitic case (hard outer layer).

The diffusion of nitrogen into the surface of steel, forming hard nitrides and improving wear resistance, hardness, and fatigue strength.

Gaseous nitriding requires heating steel to around 500°C for 2-4 days in an ammonia gas atmosphere.

Nitriding is typically used for hardening finished machined and heat-treated steels without affecting the core properties.

Nitriding doesn't require quenching after the process, unlike carburising.

Nitriding is done at a lower temperature than carburising because nitrogen diffuses slower than carbon.

A process used to change the surface hardness of steel by introducing carbon and/or nitrogen into its structure. This is achieved through diffusion, where the elements are absorbed into the steel at a high temperature.

A type of heat treatment where the surface of a steel component is heated to a high temperature and then rapidly cooled, resulting in a hard and brittle surface layer. This process is used to improve the wear resistance and strength of the surface.

A type of heat treatment where the surface of a steel component is heated using an electromagnetic field, resulting in a hard and brittle surface layer. This process is similar to flame hardening but offers greater control and precision.

A process used to increase the surface hardness of a steel component by diffusing carbon into its surface. This process is used to improve the wear resistance and strength of the surface.

A process similar to carburising where nitrogen is diffused into the surface of a steel component, improving surface hardness, wear resistance, and fatigue strength.

This process combines aspects of both carburising and nitriding, introducing both carbon and nitrogen into the steel's surface. It results in increased hardness, wear resistance, and fatigue strength, making it suitable for a wide range of applications.

These types of heat treatments are typically used when a specific area of a component needs to be hardened without altering the composition of the steel. They involve localized heating and rapid cooling.