A Comparative Study of Elastic Constants of NiTi and NiAl Alloys from First-Principle Calculations

plane shear modulus c44 increases with increasing Ni content, while basal-plane shear modulus c 0 decreases. In the above composition ranges however the transformation temperature of NiAl increases with increasing Ni content while that of NiTi decreases from experimental observation. The softening of c 0 is experimentally observed only in NiAl, and the decrease of c 0 with increasing Ni content is responsible for the increase of transformation temperature. The result of the present work demonstrates that, besides c 0 , c44 also in∞uences