Effect of pressure pulse shape on power density and laser spot size in laser shock peening of titanium alloy samples

The pressure pulse shapes were determined for round and square laser spots at different radiation power densities using a photon Doppler velocimeter. The obtained pressure pulse shapes made it possible to refine the mathematical model of the laser impact processing process in terms of constructing a residual stress diagram. The velocity profile of the free surface of the sample was measured during laser shock peening with a relative radiation power density of 0.10...0.63 on flat titanium alloy samples with a thickness of 0.35...1.20 mm. A characteristic profile of the elastic-plastic wave in a titanium alloy sample was obtained. It was found that for a round laser spot, the pressure pulse shape remains virtually unchanged with an increase in the radiation power density, while for a square spot, the pulse duration increases by 1.6-2.3 times.
EDN: KQBHDB, https://elibrary/kqbhdb

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