High precision complete forming process of metal microstructure induced by laser shock imprinting

摘要

Nowadays, plastic forming technology for micro-scale parts is booming. Kinds of microstructures with high-precision, multi-function are required by modern manufacturing industry. Laser shock imprinting, as a high-efficient, high-precision, and low-cost micro-forming technology, has been widely studied. But at present, the precision of microstructure fabricated by the method was not enough, and the microstructure cannot completely replicate from micro-mold. This paper defined filling rate and vertical degree to measure the forming precision of microstructures and realized microstructure complete forming with high precision (filling rate reach to 100% and vertical degree reach to 90 degrees). According to stress modes and forming precision, the forming process was divided into three stages (elastic deformation, plastic stretching, and plastic compression) in this paper. Through experiment and simulation, the surface profile, stress distribution, thinning of metallic thickness, and roughness were analyzed in each stage. Besides, grain refinement degree and refinement mechanism was explained in the paper. Therefore, by changing the micro-mold, laser shock imprinting could fabricate complex microstructure with high precision.