Study on Ti2AlC/TiAl composites with doping Ti3AlC2 by SPS

Abstract:

Ti₃AlC₂ ceramics were fabricated by in-situ reaction in the 2TiC-Ti-1.2Al system. Ti₂AlC/TiAl composites were prepared by spark plasma sintering technology in the 59.2Ti-30.8Al-10Ti₃AlC₂(wt%) system. The phase composition and microstructure of the specimens were analyzed by XRD and SEM methods. The room temperature mechanical properties were also measured. The results revealed that the in-situ Ti₃AlC₂ materials mainly consisted of Ti₃AlC₂ and TiC phases. Ti₃AlC₂ ceramics present layered structure and TiC particles distribute around the grain boundaries. The Ti₂AlC/TiAl composites prepared by SPS mainly consist of TiAl, Ti₃Al and Ti₂AlC phases. Ti₂AlC reinforcements are mainly distributed in the matrix grain boundaries, which show grain-boundary strengthening or intracrystalline strengthening effect. The density, Vickers hardness, fracture toughness and flexural strength of the Ti₂AlC/TiAl composites are 3.85 g/cm₃, 5.37 GPa, 7.17 MPa, 7.17 MPa?m_1/2 and 494.85 MPa respectively.