Effect of microfissures on fatigue properties of austenitic stainless steel weld metals

High-cycle tension–tension fatigue testing with a 0.1 stress ratio at a frequency of 20 Hz (load control at ambient temperature) was conducted on 316L stainless steel weld metals with and without microfissures. The test results show that microfissures (hot cracking) significantly decrease the fatigue properties in austenitic stainless steel weld metals. The initiation of failure for microfissure-containing samples is linked to the microfissures which show hot cracking characteristics; a smooth flowed pattern on the fissure surface.