Engineering Questions with Answers - Multiple Choice Questions
Materials Science MCQ’s – Interfacial Defects
1 - Question
Annealing twins which are found in metal have which type of crystal structure?
a) BCC
b) FCC
c) HCP
d) HCP and BCC
View Answer
Explanation: Annealing twins are predominantly found in Face-Centered Cubic structure (FCC) metals.
2 - Question
At room temperature what is an approximate order of vibration frequency in vibration per second?
a) 1013
b) 1010
c) 104
d) 107
View Answer
Explanation: Since amplitude vibration is few thousands of nanometre at room temperature. The frequency of the periodic motion is known as a vibration frequency.
3 - Question
In polymeric material the surface of which type of layer is considered to be an interfacial defect?
a) Chain ends
b) Short side branches
c) Main chain unit
d) Chain folded layer
View Answer
Explanation: Chain folded layers create/ are boundaries between two crystalline regions which results in the interfacial defect.
4 - Question
Which type of boundary exists in multiphase materials across which there is a sudden change in physical/chemical properties?
a) Phase boundary
b) Chain folded layer
c) Domain wall
d) Grain boundary
View Answer
Explanation: Chain folded layers are boundaries in case of polymeric materials. Domain wall deals with ferromagnetic and ferromagnetic materials and multiphase deals with phase boundary.
5 - Question
What is the density of polycrystalline specimen virtually identical to?
a) Singe crystal of different material
b) Single crystal of same material
c) Different crystal of different material
d) Different crystal of same material
View Answer
Explanation: Single crystal of same material will have the same crystalline structure so their density will be identical.
6 - Question
Which type of boundary causes a constant angle of tilt between lattice planes of the same type in adjacent regions of the sample?
a) Twinning boundary
b) Tilt boundary
c) Grain boundary
d) Domain wall
View Answer
Explanation: When a small grain boundary is formed due to tilt in the angle of orientation is called tilt boundary. A Twin Boundary happens when the crystals on either side of a plane are mirror images of each other.
7 - Question
Volume defect or bulk defects are which dimension defect?
a) 1 dimension
b) 2 dimension
c) 3 dimension
d) 4 dimension
View Answer
Explanation: Volume defects are three dimensional defects. Interfacial defects are two dimensional. In short volume defect is an application of interfacial defect.
8 - Question
Interfacial defect does not include which of the following defect?
a) Grain boundary
b) Twin boundary
c) Phase boundary
d) Volume defect
View Answer
Explanation: Interfacial defects are 2 dimensional defects whereas volume defect is 3 dimensional defects. Grain boundary, Twin boundary and Phase boundary are types of interfacial defect.
9 - Question
What will be the interfacial energy for domain wall?
a) Greatest compared to other interfacial defects
b) Least compared to other interfacial defects
c) Less than external surface but more than other interfacial defects
d) Less than the external surface and grain boundary but more than other interfacial defects
View Answer
Explanation: Domain wall is the boundary that separates the region having a different direction of magnetization in case of ferromagnetic and ferrimagnetic material. Hence interfacial energy is least in case of a domain. As magnetization energy is less compared to other energies.
10 - Question
Which dimension defect are interfacial defects?
a) 2 dimension
b) 1 dimension
c) 3 dimension
d) 4 dimension
View Answer
Explanation: Interfacial defect are boundary defect that has 2 dimension and normally separate regions of the materials that have different crystal structures and/or crystallographic orientations. These imperfections include external surfaces, grain boundaries, twin boundaries, stacking faults, and phase boundaries.