Superior strength-ductility synergy in a novel tailored Zr-based particle-strengthened medium W content alloys

In the present study, the tungsten medium alloys (MHAs) with excellent mechanical properties are fabricated by liquid phase sintering (LPS) and subsequent vacuum heat treatment. W nano-powder and finely dispersed Zr-based second-phase particles contribute to the microstructure optimization and performances enhancement. In these MHAs, W grains of approximately 5 μm are uniformly distributed in the γ-matrix phase, which are much smaller than those of typical tungsten heavy alloys (WHAs) (40–50 μm). The ultimate tensile strength, elongation and hardness of 75W-1(Y–ZrO2) alloys are 948 MPa, 23.1% and 393 HV1, respectively, profited from the combined effects of fine-grained strengthening, dispersed strengthening, solid-solution strengthening and deformation twinning mechanisms. Besides, the relationship between the plastic deformation and mechanical performance are systematically analyzed through electron back-scattered diffraction (EBSD) characterization. The current study provides a novel strategy for preparing medium-W-content, high-performance and low-cost tungsten-based composite material.