Slow crack propagation in Y-TZP/metal composites

The paper presents results of investigation on slow crack propagation of two composites in TZP/metal system, where 10 vol.% of tungsten and molybdenum were used as dispersed phase. The mean grain size of the inclusions was about 2 μm. Composites were prepared by intensive attrition milling/mixing of the constituent phases in ethyl alcohol and densified by hot-pressing at 1500 °C under 25 MPa in argon atmosphere. Strength, fracture toughness and hardness were investigated. The threshold value (KI0) of slow crack propagation is higher for both composite materials when compared with TZP. Both investigated composites show similar KI0 values and maximum values of the critical stress intensity factor (KIc) by using different methods.