Research on high-temperature tensile properties and creep behavior of (TiB + TiC + Y₂O₃)/a-Ti composites

A (TiB+ TiC + Y₂O₃)/a-Ti composite and its corresponding matrix alloy were prepared by induction skull melting. The structure and properties of the two materials were studied by XRD, SEM and TEM. The results showed that the matrix alloy possessed a typical Widmanstatten structure while the composite displayed a basket-weave structure with a few equiaxed a phases formed after the reinforcements were added. The ultimate tensile strength and creep resistance of titanium matrix composite improved significantly with the introduction of reinforcements. Compared with the matrix alloy, the high-temprerature tensile properties of the composite at 650 °C have increased by approxinately 170 MPa, the creep life of the composite increased by a maximum of 348%, and the minimum creep rate decreased by one order of magnitude, showing excellent strengthening effect. For the matrix alloy, the dislocation movement during creep mainly limited by the a/ẞ interface. For the composite, the reinforcements hada good load-bearing strengthening effect, forming high density dislocation zones around the reinforcements, and promoting the precipitation of silicide, which effectively improved the creep resistance of the material. The results of this paper can provide guidance and reference for the development and application of hybrid-reinforced titanium matrix composites in the future.