Hot brittleness of Mo+30% W

Abstract

1. The alloy of Mo+30% W is susceptible to hot brittleness at 1400–1800°C. 2. Varying the tungsten content from 28 to 35% has little effect on the susceptibility to hot brittleness. Raising the carbon content from 0.002 to 0.007% sharply reduces the reduction in section in the hot brittleness range. The addition of a small amount of hafnium (∼0.2%) to the Mo+30% W alloy reduces susceptibility to hot brittleness. 3. Increasing the strain rate within the limits of 0.5–3000 mm/min reduces susceptibility to hot brittleness. 4. The hot brittleness of the alloy is due to precipitation of phase of the Mo2C type in the grain boundaries.