Laser indirect shock micro-embossing of commercially pure copper and titanium sheet

•Laser-driven flyer is used to load the workpiece in micro-embossing.•Strain states are used to interpret the variation in thickness distribution.•Increasing laser energy will increase forming depth if fracture is not detected.•Too high laser energy will induce fracture on 8 μm copper and 13 μm titanium.•With further development, the new technique can realize the blanking forming.

Laser indirect shock micro-embossing is a novel micro-high velocity forming technique, which uses laser-driven flyer to load the workpiece. In this paper, laser indirect shock micro-embossing of commercially pure copper and titanium sheet are investigated using both experimental and numerical methods. A fully 3-D finite element mode is proposed to simulate the transient deformation behaviors. The effects of material and laser energy on the deformations are investigated experimentally. Thickness distribution at the cross-section of the micro-channel is analyzed experimentally. Strain states during micro-embossing are used to interpret the variation in thickness distribution. Fracture along the inner edges of the micro-mould occurs for 8 μm copper when the pulse energy is 1200 mJ, 1380 mJ and 1550 mJ. Moreover, the 13 μm titanium is completely sheared off along the inner edge of the micromould when the pulse energy is 1550 mJ. With further development, the laser-driven flyer technique can realize the blanking forming. And experimental data obtained are then used to validate the corresponding simulation model. The results show that the finite element analysis can predict the final shape of the work piece properly.