High temperature fracture toughness of TZM alloys with different kinds of grain boundary particles

The elastic-plastic fracture toughness JIC of two titanium-zirconium-molybdenum (TZM) alloys with different kinds of grain boundary particles was estimated at elevated temperatures using the convenient JIC test method with a suitable depth of side-groove for determining the JIC at the maximum load point. It was found that the convenient JIC test method can be successfully applied to evaluate high temperature fracture toughness at least up to 1200 °C. The JIC values at temperatures ranged from 800 °C to 1200 °C were almost constant regardless of temperature, while the JIC values of the TZM with carbide particles were higher than those of the TZM with oxide particles. The TZM with different forging rates showed similar JIC values, which suggested the effect of forging rate would be not significant at high temperatures.