Effect of aluminum addition on the densification behavior and mechanical properties of synthesized high-purity nano-laminated Ti3SiC2 through spark plasma sintering

To reveal the effect of Al content on the purity and mechanical properties of Ti3SiC2, the powder mixture of 1Ti/1.2Si/2TiC/xAl (x = 0-0.4) were sintered to synthesize Ti3SiC2 through spark plasma sintering (SPS). The sintering process was conducted at 1150 °C for 8 min under a pressure of 40 MPa. To evaluate the phase constituents and morphology of the sintered samples, X-ray diffraction and field emission scanning electron microscopy were used. It was found that addition of Al from 0.2 to 0.4 mol in the starting powder mixture led to synthesis of high-purity Ti3SiC2. Besides, with increasing the Al content in the starting powder mixture, the densification behavior of sintered samples was promoted. The results showed that the Vickers microhardness of high-purity samples became almost same at higher loads and moreover the measured Young's modulus (E) of the high-purity Ti3SiC2 samples were near to each other and increased with promoting the densification.