Synthesis and mechanical properties of Ti3AlC2 by spark plasma sintering

Abstract

In this paper, spark plasma sintering (SPS), after hot isostatically pressing (HIP) method was reported as a new approach to prepare bulk polycrystalline samples of Ti3AlC2. The ternary carbide was fabricated by spark plasma sintering (SPS) at a pressure of 22 MPa and temperature of 1250°C. The raw materials, elemental powders of Ti, Al and activated carbon, were pretreated in the following different ways prior to SPS: one way was to obtain porous Ti3AlC2 by self-propagating high-temperature synthesis (SHS) from mixture of Ti, Al and C, and then densify the product by SPS; the second way was to synthesize Al4C3 from Al and C firstly, and then mix powders of Ti and C with synthesized Al4C3 to fabricate bulk Ti3AlC2 by SPS. Obtained polycrystalline Ti3AlC2 ceramics had excellent mechanical properties: density was 4.24 ± 0.02 g/cm3, flexural strength was 552 ± 30 MPa and fracture toughness (KIC) was 9.1 ± 0.3 MPa · m1/2. It could be concluded that SPS method was a useful method to synthesize bulk Ti3AlC2 with excellent properties in a very short time and easily sintering process. The optimal conditions to synthesize Ti3AlC2 were also discussed.