Ultrahigh-Strain-Rate-Predicting Method for Nanosecond-LaserInduced Shock on Aeronautical Composite Materials

Laser shock adhesion test manifests its superiority in detecting kiss bonding and weak bonding in aeronautical composite materials. However, the strain rate in the pulse laser shock test is approximately 10⁵–10⁶ s⁻¹ (an ultrahigh strain rate), which causes the current static or quasi-static constitutive models, failure criteria, and damage evolution to be no longer applicable. Therefore, this paper proposed the use of a three-dimensional orthogonal anisotropic constitutive model of strain-rate dependence, in which modulus and strength are proportional to the strain rate and follow a logarithmic relationship. The finite element model was created by dividing each layer of the composite material separately and further meshing each layer. The propagation rules of laser-induced plasma shock waves in the composite materials were calculated. The delamination locations and the particle velocity at the backside of the specimen were compared with experiment. It proves that the constitutive models of strain rate dependence are suitable for calculating the laser-induced shock impact on aeronautical composite materials.