Sound velocities and elastic-constant averaging for polycrystalline copper

Abstract

This study deals with the tensor-averaging problem, with the relationship between single-crystal and polycrystalline elastic constants. For polycrystalline copper, sound velocities were measured within a 0.1% inaccuracy at T=295K. Comparison with average values from twelve previous studies shows agreement within 0.2% in vt, 0.1% in ve, and 0.1% in v1. Among eight elastic-constant averaging methods, the Hershey-Kroner-Eshelby method works best for copper's polycrystalline and single-crystalline Debye temperatures differ by about 9K.