Residual Stress Effects on Surface Crack Growth of Rotorcraft Dynamic Components

The effect of residual stresses on part-through crack growth in rotorcraft dynamic components has important implications for maintenance decisions. It affects inspection intervals, method of inspection, investigation of service failures, and design for damage tolerance requirements. The experimental evidence of residual stress effects on part-through crack growth has been previously reported by the authors. This paper takes the data a step further by correlating the pattern of the crack propagation with scatter in the crack growth data, for a better understanding of the residual stress effect on fatigue crack growth of a partthrough surface crack. These results may help provide guidelines for damage tolerant design and life management of rotorcraft dynamic components.