title: Attenuation of laser generated ultrasound in steel at high temperatures; comparison of theory and experimental measurements.
abstract: This article reexamines some recently published laser ultrasound measurements of the longitudinal attenuation coefficient obtained during annealing of two steel samples (DP600 and S550). Theoretical attenuation models based on perturbation theory are compared to these experimental measurements. It is observed that the Rayleigh attenuation formulas provide the correct qualitative agreement, but overestimate the experimental values. The more general theoretical attenuation model considered here demonstrates strong quantitative agreement, which highlights the applicability of the model during real-time metal processing.
authors.affiliation: Army Research Laboratory, Vehicle Technology Directorate-Mechanics Division, 4603 Flare Loop, Aberdeen Proving Ground, MD 21005-5069, USA. Electronic address: christopher.m.kube.ctr@mail.mil.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Kube
keywords: Additive manufacturing; Grain size; Laser ultrasound; Process monitoring; Ultrasonic attenuation