In Situ Synthesis of (TiC + Ti3SiC2 + Ti5Si3)/Ti6Al4V Composites with Tailored Two-scale Architecture

In situ TiC particle, Ti3SiC2 bar and ultrafine Ti5Si3 needle reinforced Ti6Al4V (TiC+Ti3SiC2+Ti5Si3)/Ti6Al4V) composites with a tailored distribution were sucessfully designed and fabricated. The first-scale tailored architecture of reinforcement is the in situ synthesized Ti3SiC2 bars and near-equiaxed TiC particles on the network boundary around Ti6Al4V particles. The secondary-scale architecture is the ultrafine Ti5Si3 needles precipitated in intergranular beta phase of center Ti6Al4V matrix particle. The results showed that the two-scale tailored architecture of different reinforcements can significantly improve strength remained with moderate ductility of the composites.