Effects of plating thickness on SiCp /Al composite brazed joint structure and performance

Abstract To clarify the effects of plating thickness on the structure and performance of the brazed joints of a SiCp/Al composite, the surface of the SiCp/6063Al composite was treated with electroless nickel plating. The microstructure, shear strength, air-tightness, and fracture morphology of the nickel-plated SiCp/6063Al composite brazed joints were analyzed by SEM and other experimental methods. The results demonstrated that the structure and morphology of the brazing seams of the SiCp/6063Al composite with different plating thicknesses were basically the same. Specifically, the structure of the brazing seam was mostly dense, without holes or gaps. The shear strength of brazed joints increased with the nickel plating thickness. The brazing of nickel-plated SiCp/6063Al composite with a plating time of 30 min, brazing temperature of 290 ℃, and holding time of 30 min led to brazed joints with a high shear strength and good air-tightness. According to the analysis of the shear fracture morphology and the EDS spectrum the feature region of the brazed joint, fractures of the brazed joint mainly occurred in the brazing filler layer and at the junction of the brazing filler and nickel plating.