The Mechanism and Experimental Study on Laser Peen Forming of Sheet Metal
Laser peen forming of sheet metal is a new plastic forming technique based on laser shock waves, which derives from the combination of laser shock processing and conventional shot peening technique, it uses high-power pulsed laser replacing the tiny balls to peen the surface of sheet metal, when the laser induced peak pressure of shock waves exceeds the dynamic yield strength of the materials, the sheet metal yields, resulting in an inhomogeneous residual stresses distribution in depth. The sheet metal responds to this residual stress by elongating at the peened surface and effectively bending the overall shape. On the basis of analyzing the mechanism of laser peen forming, the line-track-peening experiments of 45 steel sheets with 2 mm thickness were carried out; a curved sheet metal with deep layer of residual compressive stress was obtained. The preliminary experiment result shows that laser peen forming can offer desirable characteristics in shaped metals and is a valuable technique for producing components for a range of industries.