STRESS INTENSITY FACTORS FOR RADIAL CRACKS IN THICK-WALLED CYLINDERS .2. COMBINATION OF AUTOFRETTAGE AND INTERNAL-PRESSURE

When a cylinder undergoes a combination of residual stress (due to aut ofrettage process) and internal pressure, the total stress intensity f actors (SIF) cannot be always obtained with linear superposition of K( Io) (due to internal pressure) and K(la) (due to autofrettage process) . This paper investigates the total SIF due to a combination of autofr ettage and internal pressure. The total SIF for some crack configurati on and load conditions is evaluated using a non-linear analysis, and t he comparison of non-linear analysis results with linear superposition results shows that there is a great difference between two results fo r certain crack configurations and load conditions.