In strain hardening apart from changes in mechanical properties re are physical changes like decrease in density, a small increase in rmal coefficient of expansion.

When two dislocations of opposite sign are on located on same slip plane two dislocations exert an attractive force and n y will start moving towards each or on meeting dislocation annihilation takes place.

In recrystallization new grains are formed with small nuclei and y grow until y cover whole parent material. Therefore, new grain structure is fine and hence grain structure is refined.

When strain-relief crystallization takes place dislocation climb, an increase in density, and a decrease in electrical conductivity. During strain-relief crystallization interaction of unlike signed dislocation is observed.

Dislocation density is defined as total dislocation length per unit volume and unit of length is mm and that of volume is mm³ refore, unit of dislocation density will be mm^-2.

When a body is heated strain on body decreases whereas it increases when defects like line defects, point defects and dislocation are present in lattice.

The critical resolved shear stress is independent of time and for a given material at a given temperature its value remains constant. It varies with a change in temperature.

Grain size reduction increases hardness, toughness and strength of material. Elasticity is not increased by grain size reduction.

Slip planes occur in planes where atom density is high and hence atoms are closely packed. Furr, direction of slip plane is same as that of translation vector which is shortest.

Lüders lines isn’t a correct term for bands in yield point phenomenon. While Lüders bands, Hartmann lines, stretcher stains are a correct term which can be used for bands in yield point phenomenon.