Description:
In the present study, a novel type of titanium matrix composite with a quasi-network structure was successfully fabricated by hot-press sintering Ti6Al4V powder and Ti2AlC precursor at 1200 ℃ and 25 MPa. To explore the effect of Ti2AlC content on the microstructure and properties of composites, 1-8 vol% Ti2AlC was selected. The microstructural analysis shows that the initial Ti2AlC is transformed into TiCx, and Al atoms diffused into the Ti6Al4V matrix to form Ti(Al) solid solution. And this reaction resulting the α→β transformation temperature of Ti become lower based on thermal analysis. With the addition of Ti2AlC increases, the morphology of α phase gradually moved to equiaxed grain and the grain size of it becomes smaller, while the relative proportion of α/β changing. When the addition of Ti2AlC is 3vol%, the composite shows the significant improvement of strength with less ductility loss, with the tensile yield strength of 939 MPa, ultimate tensile strength of 1007 MPa, compressive yield strength of 1292 MPa and ultimate compressive strength of 2041 MPa. This improvement of strength is attributed to fine-grain strengthening, solid solution strengthening and second phase strengthening. And the theoretical calculation indicates that solid solution strengthening dominates the improvement efficiency