Ag-based filler metal wetting behavior and brazed joint performance on SLMed Ti/TiB2 substrate

Abstract

Purpose This study aims to investigate the wetting behavior of AgCuTi and AgCu filler metals on selective laser melting (SLMed) Ti/TiB2, and to analyze the microstructure and fracture characteristics of SLMed Ti/TiB2/AgCuTi or AgCu alloy/SLMed Ti/TiB2 brazed joints. The wetting behavior of AgCuTi and AgCu filler metals on the selective laser melted (SLMed) Ti/TiB2 has been studied. The analysis of microstructures and fracture characteristics in vacuum-brazed SLMed Ti/TiB2 substrate, using AgCuTi and AgCu filler metals, has been conducted to elucidate the influence of brazing temperature and alloy composition on the shear strength of the brazed joints. Design/methodology/approach Brazing SLMed-Ti/TiB2 in a vacuum using AgCuTi and AgCu filler metals, this study aims to explore the optimal parameters for brazed joints at various brazing temperatures (800°C−950°C). Findings The findings suggest that elevated brazing temperatures lead to a more extensive diffusion region in the joint as a result of the partial melting of the filler metal. The joint composition changes from distinct Ti2Cu layer/TiCu layer/filler metal to a-Ti (ss) + ß-Ti (ss)/TiCu. As the brazing temperature increases, the fracture mode shifts from brittle cleavage to ductile fracture, mainly attributed to a decrease in the CuTi within the brazed joint. This change in fracture behavior indicates an improvement in the ductility and toughness of the joint. Originality/value The originality of this study lies in the comprehensive analysis of the microstructure and shear strength of vacuum brazing SLMed Ti/TiB2 using AgCuTi and AgCu filler metals.