LAUSR

The effects of shot peening (SP) on the fatigue strength of partially stabilised zirconia were studied. Smooth specimens and specimens containing a surface pre-crack with depths in the range 35–110 μm were subjected to SP. The cyclic fatigue tests were performed using a three-point bending setup. SP introduced compressive residual stresses on the specimens and improved their fatigue strengths. The shot peened specimens with pre-crack depths ≤ 50 μm fractured outside the pre-crack area and exhibited considerably high fatigue limits, equivalent to those of the shot peened smooth specimens. Therefore, the pre-cracks with depths ≤ 50 μm could be rendered harmless by SP, which was confirmed by the theoretical estimations based on fracture mechanics.