Chemical reaction and stability of Ti3SiC2 in Cu during high-temperature processing of Cu/Ti3SiC2 composites

Chemical reactions and stability of Ti3SiC2 in Cu during processing of Cu/Ti3SiC2 composites in the temperature range of 900-1070 degreesC were investigated using X-ray diffraction and scanning electron microscopy. The results indicated that Cu reacted with Ti3SiC2 above 900 degreesC, and the reaction products were closely related to the reaction temperature and the relative ratio of Cu and Ti3SiC2. At low Ti3SiC2 content or temperatures below 1000 degreesC, Cu(Si) solid solution and TiCx were formed, whereas at high reaction temperature and high Ti3SiC2 content, Cu-Si intermetallic compounds like Cu5Si, Cu15Si4 and (Cu, Si) eta' as well as TiCx were observed. The transporting process for the reaction was investigated and described. It was found that de-intercalation of Si from Ti3SiC2 dominated the reaction, which dissolved in copper to form Cu(Si) solid solution or Cu-Si intermetallic compounds such as Cu5Si, Cu15Si4 and (Cu, Si) eta'. TiCx was always present as the decomposition product of Ti3SiC2.