Single-crystal elastic constants of Al2Cu

Abstract

The single-crystal elastic constants of tetragonal Al2Cu have been measured over the temperature range 4.2–300 K by the pulse-echo-overlap technique. The directly measured constants show a normal monotonic decrease in magnitude with increasing temperature but with C44 showing the least change. The anisotropy ratios C33/C11, C12/C13, and C44/C66 show only small percentage changes between 4.2 and 300 K, but 2C44/(C11−C12) changes by nearly a factor of 2. Comparison of data for Zr2Ni with that for Al2Cu indicates some importance of atomic size effects. A Debye temperature of 402 K was evaluated from the elastic constants at 4.2 K.