Question

want the answer in word I do not want handwriting

Material processing industry is the backbone of the manufacturing sectors and it produces large volume of metal alloys by primary processing like casting, forging and heat treatment. The effect of primary processing leads to the formation of defects in the crystal lattice. 3 Answer the following questions based on the above statements: i. Why is edge dislocation affecting the mechanical properties in the crystal structure of metal? Justify your answer with a neat diagram (using pencil). (2 marks) Sketch (using pencil) and identify the defect in which missing atom occupies at interstitial position in the crystal structure during the heat treatment process. (3 marks) ii.

Answer 1

1) Edge dislocation: The edge dislocation figure is as shown in figure below.

This kind of defect occurs when the extra atom is inserted into the plane of crystal lattice.

Because of this, slipping of atoms takes place & material starts deforming. Hence, when external force is applied, material deformation takes place, when this defect is present.

In this way, it is affecting material properties.

Edge Dislocation

2) The defect in which missing atom occupies at interstitial position is called as Frenkel defect.

The frenkel defect is shown in the figure below.

In frenkel defect, both vacancy and interstitial defects takes place.

As the atom moves from its position, vacancy gets created & this atom moves to the interstitial place, so interstitial defect takes place.

о С Frenkel Defect