Engineering Questions with Answers - Multiple Choice Questions

# Materials Science MCQ’s – Isomorphous Alloys

1 - Question

How many components are present in unary phase system?
a) 1
b) 2
c) 3
d) 4
Explanation: Unary phase systems which consist of a single component. Phase systems with two components are called binary systems and those with three are called ternary systems.

2 - Question

In a binary isomorphous system which of the following is true?
a) The two metals are completely miscible in each other in liquid as well as solid form
b) The two metals are completely immiscible in each other in liquid as well as solid form
c) The two metals are completely miscible in each other in liquid form only
d) The two metals are completely miscible in each other in solid form only
Explanation: In a binary isomorphous system, the two metals are completely miscible in each other in liquid as well as solid form.

3 - Question

The number of components are 2, the number of phases are 3 and degrees of freedom are 0. Then which of the following equilibrium is it?
a) Invariant
b) Univariant
c) Bivariant
d) Trivariant
Explanation: We can solve the above question by using Gibb’s phase rule. When the given values are put in the equation the value is obtained to be zero which makes the reaction invariant.

4 - Question

The number of components are 2, the number of phases are 2 and degrees of freedom are 1. Then which of the following equilibrium is it?
a) Invariant
b) Univariant
c) Bivariant
d) Trivariant
Explanation: We can solve the above question by using Gibb’s phase rule. When the given values are put in the equation the value is obtained to be one which makes the reaction univariant.

5 - Question

The number of components are 2, the number of phases is 1 and degrees of freedom are 2. Then which of the following equilibrium is it?
a) Invariant
b) Univariant
c) Bivariant
d) Trivariant
Explanation: We can solve the above question by using Gibb’s phase rule. When the given values are put in the equation the value is obtained to be two which makes the reaction bivariant.

6 - Question

An alloy 30 wt% Ni- 70wt % Cu at 1315 °C (2400 °F) will lie in which state?
a) Solid state
b) Liquid state
c) Mixture of solid and liquid state
d) α state
Explanation: An alloy 30 wt% Ni- 70wt % Cu at 1315 °C (2400 °F) will lie in the liquid state which we can observe from its phase diagram

7 - Question

An alloy 30 wt% Ni- 70wt % Cu at 1095 °C (2000 °F) will lie in which state?
a) Solid state
b) Liquid state
c) Mixture of solid and liquid state
d) α state
Explanation: An alloy 30 wt% Ni- 70wt % Cu at 1095 °C (2000 °F) will lie in the region where it is in α state which can be observed from its phase diagram.

8 - Question

The copper-nickel system is an example of solid solution hardening.
a) True
b) False
Explanation: The above statement is true and the copper-nickel system is an example of solid solution hardening. Therefore changes are caused due to distortion in its lattice structure.

9 - Question

In a copper nickel system the tensile strength increases with an increase in the percentage of nickel in the alloy.
a) True
b) False
Explanation: The above statement is true. As nickel has more tensile strength than copper, the tensile strength of copper increases with the increase in the percentage of nickel in the alloy.

10 - Question

In which of the following the alloy is rapidly cooled?
a) Anealing
b) Coring
c) Hot working
d) Cold working