The decrease in fatigue resistance of an austenitic Fe-Mn-Al steel,due to the presence of cathodically precharged hydrogen,has been evaluated in the present study.Compact tension (CT) specimens precharged with hydrogen and a control without hydrogen charging were subjected to sinusoidal,tension-tension and cyclic loading at stress ratios (R) of 0.1,0.3 and 0.5.The tests were conducted in the applied stress intensity range ( DELTA K) of 10-60 MPam~(1/2) at 10 Hz frequency and plos of fatigue crack growth rate (FCGR) vs DELTA K were obtained.It has been observed that the presence of internal hydrogen leads to an enhancement of FCGR by a factor of 2 to 15 depending on the value of DELTA K and R.The enhancement increased with increase in R and DELTA K,and was maximum for all R values around 40 MPam~(1/2).
展开▼
