Effects of small defects and hydrogen on the fatigue strength of Ni-Resist

Abstract

Rotating bending fatigue tests were conducted on the specimens with artificially introduced defects to investigate the effect of casting defects on the fatigue strength of austenitic ductile cast iron (Ni-Resist). Either of three kinds of defects: a single drilled hole, a 3-hole defect or a circumferential notch, was introduced onto the specimens to simulate casting defects with various shapes and sizes.

After investigating the impact of such small defects, the high-cycle fatigue properties of both hydrogen-charged and uncharged materials were examined.