Welding tantalum by resistance spot welding with metal plating interlayer

The main objective of this study is to improve the bonding of similar pure tantalum by resistance spot welding (RSW) with a metal plating interlayer. In order to improve the bonding strength and mechanical properties and to understand the mechanism of this welding method. Several metals were used as an interlayer in the welding process (aluminum, copper, silver) each with a thickness of 50 um, in addition to a fourth metal plating interlayer double consisting of two layers of aluminum interspersed with copper. The thickness of pure tantalum was 0.2 mm where the welding time (3 seconds) and welding current (9100 amperes) were used with constant pressure. Optical microscopic examinations of the welded assemblies were performed to determine the mechanism of joint formation, and scanning electron microscopy (SEM) and X-ray diffraction (XRD) as well were used to assess the viability of employing interlayers, as well as assessment of joint strength by tensile strength test (TST). the mechanical properties of welding have been improved it was found from optical microscopy and tensile strength test that the use of aluminum as an interlayer metal plating gave the best results, where the increase in tensile strength test results was a percentage of 32% compared with the test results for welded tantalum produced by classical resistance spot welding having no interlayer, followed by tantalum welded with copper interlayer and then interlayer of silver.