Ultrasonic Wave Propagation in a Nickel Single Crystal

The propagation of ultrasonic energy in a nickel single crystal by an improved pulse technique has been employed to investigate the behaviour of the dynamic elastic constants of, and the energy losses in the specimen, with and without an applied magnetic field. The dynamic elastic constants behave according to Zener's theory of anelasticity in the test range of frequencies. Values of the relaxation time for internal atomic rearrangement and ratios of the relaxation strengths for shear and compressional waves are evaluated for the sample. Energy losses are substantially reduced when the sample is magnetized to saturation.