Dynamic elastic displacements due to pulsed laser absorption at the surface of an infinite plate

The thermoelastic strain accompanying absorption of pulsed laser radiation was modelled as a combination of elementary force dipoles. The elastic displacements due to each dipole component and the complete source were calculated using the dynamic elastic Green's tensor for an infinite plate. The results for a typical laser pulse incident on an austenitic steel plate show that as the source-receiver distance increases, the elastic displacements become dominated by a Rayleigh wave on the plate surface where absorption occurs, and by head waves on the surface opposite the source.