Study on structure and property of tungsten alloy strengthened with dispersed La2O3

La2O3/W composite powders were prepared with mechanical high energy ball milling, and pressed and sintered at 1823 K for 1 h to be a tungsten alloy strengthened with dispersed La2O3. The study results of their microstructure and mechanical properties show that the microstructure of sintered tungsten is very homogeneous with grain size of 10 mu m similar to 15 mu m and distribution of La2O3 particles on the tungsten grain bundaries. The flexural strength of the alloy reaches 475 MPa, 35% higher than the pure tungsten of the same density. The morphology of fracture surface shows that the fracture mode of W alloy changes from the W grain fracture to the intergranular and transgranular fracture after La2O3 particles being added. The influences of La2O3 particles on the microstructure and properties were discussed.