title: Evaluation of third-order elastic constants using laser-generated multi-type ultrasound for isotropic materials.
abstract: Within the linear elasticity approximation the speed of a small-amplitude sound in conventional linear elasticity is determined only by the second order elastic (SOE) constants and the density of the medium. Subjecting the conveying solid to a static strain of a sufficient magnitude introduces the third-order elastic (TOE) constants in the equation of the sound speed. In this work we applied a homogeneous isotropic deformation caused by a thermal expansion of an aluminum alloy sample. Velocities of three acoustic modes: longitudinal, shear and Rayleigh waves were measured as functions of temperature within a range of 25-100 °C. Two TOE constants C111 and C112 were evaluated in an assumption that the third independent module C144 is far smaller than the former two.
authors.affiliation: College of Science, Nanjing University of Science & Technology, Nanjing 210094, China.
authors.forename: Li-Ming
authors.initials: LM
authors.lastname: Dong
authors.forename: Alexey M
authors.initials: AM
authors.lastname: Lomonosov
authors.forename: Zhong-Hua
authors.initials: ZH
authors.lastname: Shen
authors.forename: Jia
authors.initials: J
authors.lastname: Li
authors.forename: Chen-Yin
authors.initials: CY
authors.lastname: Ni
authors.forename: Xiao-Wu
authors.initials: XW
authors.lastname: Ni