Microstructural evolution during the formation of Ti3AlC2

A layered ternary carbide Ti3AlC2 was synthesized by pressureless calcining process from the mixture of Ti/Al/2TiC. Almost single phase Ti3AlC2 was obtained after calcining at 1400 °C for 1 h. The microstructural evolution during the formation of Ti3AlC2 was examined at the temperature from 900 °C to 1400 °C. Based on the results of X-ray diffractometry (XRD) and energy-dispersive X-ray spectroscopy (EDS), a possible reaction mechanism was proposed to explain the formation of Ti3AlC2. Above the melting point of aluminum, liquid Al reacts with titanium to form the intermetallic compound of AlTi. As the temperature is increased to 1400 °C, the intermetallic compound of AlTi reacts with TiC to form Ti2AlC and then, Ti2AlC further reacts with TiC to form the final product of Ti3AlC2.