Vacuum brazing of aluminium metal matrix composite (55 vol.% SiCp/A356) using aluminium-based filler alloy

Aluminium matrix composites with high volume fractions of SiC particles, as the reinforcements, are potentially suitable materials for electronic packaging. These composites, due to their poor weldability, however, have very limited applications. The microstructure and shear strengths of the bonds made in 55 vol.% SiCp/A356 composite, using an aluminium based filler alloy containing Cu, Si, Mg and Ni, were investigated in this paper. The brazing temperature had a clear effect on the bond integrity, and the samples brazed at 560 °C demonstrated good bonding between the filler alloy and the SiC particles. The maximum shear strength achieved in this work was 102 MPa.

► The proper filler metal has been developed, especially for contents of Mg and Si.
► The pressure device has been designed for specimen in vacuum brazing process.
► The accurate measurement method for shear strength of lap joint has been found.
► The brazing temperature of 560 °C has been optimised.
► The micro-mechanism has been discussed for SiCp/Al composites’ brazing joint.