Brazing of Silicon Carbide Particle Reiforced LD2 Aluminum Composites

The brazing of LD2 aluminum alloy reinforced with 10 volume percent SIC particles was studied in this paper.Each joint was made in an inert gas atmosphere furnace with a pressure of 5kPa on the faying surfaces.Mechanical shear test and metallography were performed on each joint, which showed that the bonded joint can be classified tnto four distinct areas:1 Al-Si eutectic area at the center of the joint; 2.the α-Al solid solution area next to the Al-Si eutectic area resulted from the decrease of silicon concentration in the filler metal due to the interdiffusing with base meatl; 3.SiC particles concentrated area next to the α-Al solid solution area;4.α-Al solid solution area deficient in SiC particles near the base metal.EDX unit which accompanies the SEM was also used to study the wetting and dissolution characteristics of the joining systems.Connecting it with the join structure, we give a reasonable explain to the forming of four distinct areas and the different strength and fracture feature of the joints with different temperature and time.