Effect of Si addition on the stability of Al-10Ti-5Cu-xSi alloy/SiC interface

The effect of Si addition on the interfacial stability of Al-10Ti-5Cu-xSi (x = 0, 5, 10, 15) alloy/SiC is investigated. SiC and the Al-10Ti-5Cu-xSi alloys were compacted to obtain a stable interface with 10 wt% Si. Analysis of the processing conditions and the microstructures indicated that an excellent Ti3SiC2 phase had been formed and the deleterious Al4C3 phase had been eliminated successfully by the addition of 10 wt% Si to the Al-10Ti-5Cu alloy. Formation of Ti3SiC2 increased at first and then decreased, while the formation of Al4C3 was gradually inhibited with increasing Si content. Ti3SiC2 possesses good chemical stability, and flexibility. However, Al4C3 degrades within few days, in composites exposed to ambient conditions. The presence of Ti3SiC2 at the interface and the elimination of Al4C3 together ameliorate the bonding of Al-10Ti-5Cu-xSi alloy to SiC, thereby improving the interfacial stability of Al-10Ti-5Cu-xSi/SiC.