Abstract
Alloying Mo into W-Ni-Fe heavy alloys results in solid solution strengthening of the matrix phase and yields smaller tungsten grains. However, a high alloying concentration of Ma causes a high concentration of Mo in the matrix phase at the final stage of liquid phase sintering. When the concentration of Mo in the liquid phase exceeds a critical value, a MoNi type intermetallic phase heterogeneously nucleates and grows on the surface of W-Mo grains during cooling, which imparts brittleness to the alloys. This article summarizes the recent studies regarding the effect of Mo on the microstructural evolution and mechanical properties of tungsten heavy alloy. In addition, the mechanism behind the formation of the intermetallic phase is emphasized.
