Research on temperature-assisted laser shock imprinting and forming stability

Demand for forming precision and the high-temperature stability of micro-structures is growing quickly in the fields of MEMS, optoelectronic devices, aerospace and biomedical engineering. In order to improve the precision and stability of micro-structures, and to achieve the rapid manufacture of formed parts, the temperature-assisted laser shock imprinting (TALSI) technique is proposed for fabricating large-area micro-structures on the surface of metal foil. In this study, nanosecond lasers with low energy and high frequency were used to carry out laser shock imprinting (LSI) experiments on aluminium foil at different temperatures, and recovery experiments were also implemented at different temperatures. By analysing the surface morphology, profile curve and forming depth of the micro-structures, we obtain the forming law and the optimum imprinting temperature. The influence of temperature on the plasticity, flow stress, dynamic yield strength, and deformation resilience of aluminium foil was experimentally determined, and the stress distribution at imprinting temperatures of 25 degrees C and 200 degrees C were investigated by ABAQUS software. The results indicate that warm laser shock imprinting (WLSI) can improve the forming depth, forming accuracy, high temperature stability and residual stress homogenisation of formed parts.