Static Tensile Properties near Ductile-Brittle Transition Temperature Region of W-based Composites Doped with Y₂O₃

W-based composites doped with 0.5wt% and 2.0wt% Y₂O₃ were prepared. The microstructure of the composites was investigated. The deformation characteristics near ductile-brittle transition temperature region of the composites were analyzed by tensile tests at different temperatures (25-800℃). The results show that the two composites had a large number of dislocations formed by rolling deformation, and Y₂O₃ particles played a pinning role in dislocation motion. The composite containing 2.0wt% Y₂O₃ had smaller grain size and a lower ductile-brittle transition temperature. The semi-brittle behavior of the composite containing 2.0wt% Y₂O₃ occurred during tension at 300-400℃, and the dislocation density in the fracture area was between 3.8×10¹⁵-3.9×10¹⁵ m^-2; during tension at 600-800℃, plastic deformation occurred, and the dislocation density increased to 6.2×10¹⁵-6.8×10¹⁵ m^-2.