Investigation on Joining Mechanism of SiC Particle Reinforced Aluminum Matrix Composite (Al/SiCp-MMC) by Resistance Spot Welding

摘要

The present study had investigated the joining performance of SiC particle reinforced aluminum metal matrix composite (Al/SiCp-MMC) having 1.0mm thickness by resistance spot welding processes. The welded joints were subjected to tensile-shearing tests in order to determine the strength of the welded zone. In addition both scanning electron microscopy (SEM) and optical microscopy (OM) were conducted to investigate the micro structural and micro hardness's changes of the welded joints. The results reveal that: the maximum tensile-shear strength value of welded joint was obtained in these optimum welding parameters as in 17.5kA welding current for 60 periods welding. The electrode pressure was 3.5kN. It was favorable to select relatively high welding current and short welding time for improving mechanical properties of spot welded SiCp/LY12 composite joint. In this base, the welding mechanism of resistance spot welding SiCp/LY12 composite has also been discussed in detail.