Influence of laser texturing on interfacial bonding strength of W/Cu joint by spark plasma sintering

Abstract

In this study, a spark plasma sintering(SPS) technique is used to bond tungsten(W) and copper(Cu) based on the laser texturing tungsten surface. Five microstructures, namely pristine structure, micropores1, micropores2, microgrooves, and nanoripples, were fabricated on the tungsten surface, and the effect of the microstructures on the shear properties, thermal shock resistance, and thermal conductivity of the tungsten/copper joints was investigated. W with the original planar morphology did not form an effective connection with copper, while the W with other surface structures connected well with copper. The results of the shear resistance experiments showed that the micro/nano interface structure significantly improved the shear resistance of W/Cu, where the microgroove structure presented the highest shear strength of 88.19 MPa. It was found that the volume of copper infiltrated into the microstructures had the greatest effect on the thermal shock resistance of the tungsten/copper joint. The highest number of microgroove thermal shock resistance was 297 times. The highest thermal diffusion coefficient of 82.31 mm²/s was obtained for the nanoripple specimens.