Advanced alumina composites reinforced with titanium-based alloys

New (inter)metallic-ceramic composites for high-temperature structural and functional applications are prepared via high-energy ball milling. During c ompaction by pressureless sintering, dense Al2O3/Ti-based alloy composites are formed that consist of inter-connected networks of the ceramic and the (inter)metallic phases, Ti-AI-V/Al2O3 and Ti-AI-Nb/Al2O3 composites show en hanced damage tolerance over monolithic Al2O3 i.e., fracture toughnesses up to 5.6 MPa .m(0.5) and bending strengths up to 527 MPa. The resistance aga inst abrasive wear is almost doubled with respect to monolithic Al2O3 ceram ic. Electrical resistivity scales with the ceramic volume fraction and rang es between 0.3 m Omega . cm and 55.1 m Omega . cm, with only a weak tempera ture dependence less than or equal to 700 degreesC.