Mechanical properties of Ti–W alloys reinforced with TiC particles

Composites consisting of a Ti–W solid-solution-strengthened matrix reinforced with TiC particles are produced by powder metallurgy. TiC additions increase strength but reduce ductility and matrix microhardness. Composites with 7.5 wt.% TiC show some tensile ductility (3–7%) but those with 15 wt.% TiC are brittle in tension. They are however strong and ductile in compression: Ti–15W/15TiC (wt.%) has a compressive yield strength exceeding 1200 MPa. This composite also shows tensile crack growth rates which are considerably faster than for pure titanium (by a factor 2) or Ti–15W (by a factor 2–6) and a fracture toughness which remains relatively high as compared to Ti–15W (21 vs. 34 MPa m).