Elastic Moduli of γ-MnCu Alloys

Abstract

The temperature dependence of elastic moduli has been measured for γ-MnCu alloys with Mn contents of 40, 70, 80 and 85 at.% by means of ultrasonics. In contrast to the Invar alloys, softening of C₁₁ and C′ (=1⁄2(C₁₁−C₁₂)) is observed at the paramagnetic region and C₁₁, C₄₄ and C′ show stiffening below T_N. Apart from the elastic anomaly associated with the martensitic transformation, a drastic decrease of bulk modulus with the increase of Mn content is observed for the wide concentration range of γ-MnCu system.