Effect of cerium on microstructure, wetting and mechanical properties of Ag-Cu-Ti filler alloy

Effect of cerium on microstructure, mechanical and wetting properties of Ag-Cu-Ti filler alloy was researched with optical microscopy, scanning electron microscopy and X-ray diffraction. The results indicated that addition of cerium accelerated alloying of the filler alloy, enlarged supercooled region, caused microstructural refinement and dispersed distribution of intermetallic compounds. It resulted in the increase in microhardness and shear strength of Ag-Cu-Ti filler alloy. At the same time, cerium improved wetting property of Ag-Cu-Ti filler alloy on 0.45% C steel substrate. According to experiment results, the content of cerium added in Ag-Cu-Ti filler alloy should be controlled in the range of 0.25 wt.%–0.5 wt.%.