Elastic constants and damping using ultrasonic resonance spectroscopy: Application to monocrystal and polycrystal copper

Abstract

Several authors used ultrasonic resonance spectroscopy to determine a material’s elastic‐stiffness constants, the Voigt Cij. Complementary to these are the out‐of‐phase Cij*, which give the complete elastic stiffness Cij=Cij+iCij*. Here, Cij* measurements for both monocrystal and polycrystal copper are reported. For the monocrystal case, the Cij* vary strongly with the vibrational mode. And, when interpreted against a vibrating‐string dislocation model, the Cij* present several surprises. For the polycrystal, the Cij* are much lower and nearly independent of vibration mode.