Question 1

As the tempering temp increases, hasdness of steel decreases

Accepted Answer

False

Question 2

In case of Austempering, the quenching which is carried out, from high temp is known as

Accepted Answer

Austempering involves quenching from a high temperature to an intermediate temperature and holding at that temperature until the transformation is complete, which is known as interrupted cooling.

Question 3

In Austempering process, the final phase that is obtain after complete heat treatment cycle

Accepted Answer

In the Austempering process, the steel is heated to form austenite and then rapidly cooled to a temperature where it transforms into bainite. This process avoids the formation of martensite and pearlite, aiming for a bainitic structure that offers a good combination of strength and ductility.

Question 4

After Austempering process, the phase bainite which obtain is highly hard and brittle phase

Accepted Answer

Austempering produces bainite that is not brittle but rather tough and strong, offering a good combination of strength and ductility.

Question 5

one of the following is main advantage of Austempering process

Accepted Answer

Austempering offers several advantages, including less distortion and cracking compared to martempering, eliminating the need for a final tempering process, and improving the toughness of the material.

Question 6

hardenability is nothing but……..

Accepted Answer

Hardenability refers to the ability of a metal, particularly steel, to be hardened through the depth of the material by heat treatment.

Question 7

hardenability of a metal or alloy is largely depend upon one of the following factor?

Accepted Answer

Hardenability of a metal or alloy depends on its carbon content, the presence of alloying elements, and the quenching medium used during the heat treatment process. All these factors influence the depth and distribution of hardness that can be achieved.

Question 8

One of the following defect is aride dur to heat treatment process

Accepted Answer

All of the mentioned defects, quench cracks, warping, and soft spots, can arise due to the heat treatment process. Quench cracks occur due to rapid cooling, warping due to uneven cooling or heating, and soft spots due to improper heat treatment leading to areas not being hardened as intended.

Question 9

case hardening processes are those where……..

Accepted Answer

Case hardening processes specifically aim to increase the hardness of the surface layer of a component while leaving the inner material softer, providing a combination of a hard, wear-resistant surface with a tough core.

Question 10

In carburisng process which of the following element is diffused in a metal surface?

Accepted Answer

In the carburizing process, carbon is diffused into the metal surface to improve hardness and wear resistance.

Question 11

Out of the following process,one is not valid with respect to carburising process

Accepted Answer

Carburizing can be performed using solid (pack carburizing), liquid (salt bath carburizing), or gas (gas carburizing) mediums, making all the mentioned processes valid for carburizing.

Question 12

heat treatment is never required after carburisig treatment.this statement is …………

Accepted Answer

Heat treatment is often required after carburizing to achieve the desired mechanical properties, such as hardness and strength, in the carburized layer.

Question 13

In nitriding process which of the following element is diffused in a surface layer of a steel

Accepted Answer

In the nitriding process, nitrogen is the primary element that is diffused into the surface layer of steel to enhance its hardness and wear resistance.

Question 14

one of the following is a step for the procedureof precipitation hardening or age hardening?

Accepted Answer

Precipitation hardening, also known as age hardening, involves several steps to improve the hardness and strength of certain metals and alloys. These steps include solution treatment, where the alloy is heated to dissolve solute elements; quenching, where the alloy is rapidly cooled to create a supersaturated solid solution; and aging, where the material is reheated at a lower temperature to precipitate out the solute elements in a controlled manner, thereby increasing its hardness and strength.

Question 15

One of the following metal alloy is suitable for the precipitation hardenable alloy?

Accepted Answer

Al-Cu (Aluminum-Copper) alloys are known for their precipitation hardening properties. This process involves the addition of copper to aluminum, which can then be heat-treated to improve its strength through the formation of finely dispersed precipitates within the metal matrix.

Question 16

in case of flame hardening ,the heat source is in the form of …….

Accepted Answer

In flame hardening, the heat source commonly used is an oxy-acetylene flame, which provides the intense heat required to rapidly heat the surface of the steel part to be hardened.

Question 17

in flame hardening process,the metal surface after heating to high temperature is quenched with ……

Accepted Answer

The answer of in flame hardening process,the metal surface after...

Question 18

In case of carbonitriding,by diffusion of which elements the surface become harder of a metal

Accepted Answer

Carbonitriding involves the diffusion of both carbon and nitrogen into the surface of a metal to increase its hardness.

Question 19

Dislocation are stopped by a ……

Accepted Answer

Dislocations are stopped or impeded by grain boundaries, which act as barriers to their movement. This is because the crystal structure and orientation change across a grain boundary, making it difficult for a dislocation to move from one grain to another.

Question 20

Finer grain size,higher will be the …

Accepted Answer

The answer of Finer grain size,higher will be the …
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Quiz 3: Heat Treatment Processes and Hardening Techniques for Metals and Alloys