Measurement of laser-induced dynamic strain on 2024 aluminum alloy surface

Polyvinylidene fluoride (PVDF) patch sensors were pasted beside the laser shock spot to measure the dynamic strain on the 2024 aluminum alloy surface induced by pulse lasers, and then the characteristics of the dynamic strain curves were analyzed. The results indicate that PVDF patch sensors have the characteristics of quick dynamic response and high sensitivity, and can be applied effectively to real-time measurement of laser-induced dynamic strain. During laser shock processing, the material around the shock spot of 2024 aluminum alloy is compressed first, then the compressive strain decreases. After laser shock processing, the surface particles around the shock spot of 2024 aluminum alloy are doing reciprocating motion constantly under the action of unloading rarefaction wave and surface rarefaction wave. The material around the shock spot is even in the tension. Finally, the dynamic response of the surface particles tends to stability.