Surface modification of aluminum and silicon carbide during the nitrogen-induced self-forming Al composite (NISFAC) manufacturing process

It is well known that poor wettability at the interface between the Al matrix and the reinforcing phase is a technical bottleneck in the development of aluminum matrix composites. A nitrogen-induced self-forming Al composite (NISFAC) process was developed, which is a novel concept of a composite manufacturing process that does not require vacuum or external pressure. This process employs an exothermic reaction accompanying the nitridation of Al, and the heat dissipated from the reaction enables the local melting and self-sintering of the Al powder. In this study, X-ray photoelectron spectroscopy (XPS) analysis was employed to investigate the compositional changes in monolithic SiC particles and the Al/SiC mixture during heating at 700 °C for 1 h in air, argon, and nitrogen atmospheres, respectively. In addition, XPS results were used to examine the mechanism for the surface modification of Al and SiC particles during the NISFAC process and to understand why self-sintering only occurs in a nitrogen atmosphere.