Variation in the Martensitic Transformation Temperatures and Dislocation Density on Thermal Cycling of Quenched Ni₅₁Ti₄₉ Alloy

The aim of the paper was to study the relation between variation in the dislocation density and martensitic transformation temperatures on thermal cycling of the quenched Ni₅₁Ti₄₉ alloy undergoing the B2 ↔ B19' martensitic transformation. The results showed that the transformation temperatures decreased on thermal cycling. At the same time, the dislocation density sharply increased during first 40 cycles, then it decreased by the 100th cycle and increased again on further cycling from 100 to 500 cycles. Thus, a variation in the dislocation density was not the only reason for a variation in the martensitic transformation temperatures on thermal cycling.