Investigation on failure mechanism of the absorption film subjected to double-sided laser shock processing

Abstract

In this paper, the failure mechanism of the absorption film (AF) subjected to double-sided laser shock processing (DSLSP) was investigated. The propagation of laser-induced stress wave in the multilayer material and the deformation process of the AF were analyzed with finite element method, and the corresponding experiments were carried out to verify the calculated results. The three-dimensional topographies of the shocked AF and the substrate were measured, and scanning electron microscope (SEM) was also used to observe the irradiated surface. The investigations show that the transmission and reflection of stress waves in the multilayer material produce outward stretching effect on the AF, which attempts to divorce the AF from the substrate. The AF bulges from the substrate with damped oscillation if the intensity of divorced stress wave exceeds the adhesion strength between them, and the shallow depressed crater is also left on the surface of substrate simultaneously. If the multiple DSLSP proceeds on the bulged AF, it ruptures and loses the protection to the substrate.