Deck 3: Heat Treatment Processes and Hardening Techniques for Metals and Alloys

Question 1

As the tempering temp increases, hasdness of steel decreases

Answer 1

False

Question 2

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

A)fast cooling
B)slow cooling
C)interrupted cooling
D)none of the above

Answer 2

interrupted cooling

Question 3

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

A)austenite
B)bainite
C)martensite
D)pearlite

Answer 3

bainite

Question 4

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

Question 5

one of the following is main advantage of Austempering process

A)less distortion and cracking than martempering
B)no need of final tempering process
C)improvement in toughness
D)all of the above

Question 6

hardenability is nothing but……..

A)ability of metals to get high hardness
B)ability of metals to reduce brittleness
C)ability of metals to get through harden
D)none of the above

Question 7

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

A)the carbon content of a steel
B)the alloy content of steel
C)quenchng medium
D)all of the above

Question 8

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

A)quench crack
B)warping
C)soft spots
D)all of the above

Question 9

case hardening processes are those where……..

A)complete component is through harden
B)complte component is melted
C)only surface of the component ,whose hardness is incresed
D)all of the above

Question 10

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

A)nitrogen
B)oxygen
C)carbon
D)carbide dioxide

Question 11

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

A)solid
B)liquid
C)gas
D)all of the above

Question 12

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

A)false
B)true
C)not applicable
D)none of the above

Question 13

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

A)carbon
B)carbon and nitrogen
C)nitrogen
D)all of the above

Question 14

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

A)solution treatment
B)quenching
C)aging
D)all of the above

Question 15

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

A)al-zn
B)al-ni
C)al-cr
D)al-cu

Question 16

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

A)lpg gas flame
B)furnace oil flame
C)oxy-acetylen flame
D)none of the above

Question 17

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

A)oil
B)brine water
C)water
D)all of the above

Question 18

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

A)only carbon
B)carbon and nitrogen
C)only nitrogen
D)none of the above

Question 19

Dislocation are stopped by a ……

A)nuceation
B)grain growth
C)grain boundry
D)none of the above

Question 20

Finer grain size,higher will be the …

A)hardness
B)ductility
C)yield stress
D)none of the above

Question 21

Work hardening also called as

A)precipetation hardening
B)hardening
C)strain hardening
D)none of the above

Question 22

some materials can not be work hardened at normal ambient temp. such as …….. Material.

A)niobium
B)indium
C)beryllium
D)none of the above

Question 23

In solid solution strengthening to ……the hardness of material.

A)decreases
B)increases
C)reduced
D)none of the above

Question 24

The number of solute atoms is more……will be the local distortion in the lattice.

A)greater
B)smaller
C)less
D)none of the above

Question 25

The press of finely distributed …….particles increases the elastic limit.

A)soft
B)hard
C)atomic
D)none of the above