This work proposes a micro-shear clinching process by laser shock for joining similar and dissimilar metal foils. The joint appearance and cross-section were investigated to determine basic process parameters. The soft punch thickness was 100 μm. The numbers of laser pulses on the upper and lower foil sides were set as two and one, respectively. Joint deformation was divided into three stages and we investigated the deformation law of the joints. The process windows of the Al foil combinations were acquired to determine a reasonable range of process parameters for obtaining qualified joints. The mechanical properties and failure modes of different joints were analyzed to identify the process characteristics. Mechanical properties were related to shear test directions and were influenced by upper and lower foil thicknesses. One failure mode was observed in the parallel shear test, and four failure modes were observed in the perpendicular shear test. These modes were determined by the differences between upper and lower foil thicknesses. Results showed that the proposed process can be used to join Al and Cu foils successfully. The laws governing the mechanical properties and failure modes of dissimilar materials were similar to those governing the mechanical properties and failure modes of similar materials.
Keywords: failure mode; laser shock; metal foils; micro clinching; process window.