Fatigue Crack Growth in Autofrettaged Thick-Walled High Pressure Tube Material

Abstract

ABSTRACTFatigue crack growth studies have been made on C-shaped and ring specimens taken from as-received and autofrettaged 4333 M4 thick-walled tubing. The ring specimen was chosen because it enables cracks to be propagated through the same residual stress distribution as that present in the tubing. It is shown that the reduced crack growth rates measured close to the bore in autofrettaged tubing can be attributed to the presence of compressive residual stresses there and can be explained in terms of the contribution of these stresses to the stress intensity factor range applied.