The effect of the in-situ hybrid Ti_5Si_(3p)/Ti_2AlN_w on the microstructure and mechanical properties of TiAl

摘要

A Ti(5)Si(3)p/Ti2AlNw synergistically reinforced TiAl composite (TTRTC) was fabricated by the addition of Si3N4 particles after ball milling. Both the Ti5Si3 and Ti2AlN show good interface matching with the TiAl matrix. In this composite, the average lamellar width was refined to 22.4 nm, the compressive strength (at 1073 K) was improved from 648 MPa to 910 MPa and the fracture toughness was improved from 24.17 MPa/m(2) to 30.67 MPa/m(2). The effective refining, the synergistic effect of transgranular Ti2AlNw and intracrystalline Ti(5)Si(3)p are the key factors in improving both the strength and toughness of the alloy.