Behavior of 321 stainless steel under engineering stress and strain controlled fatigue. (November 2016)

• Record Type: Journal Article
• Authors: Prasad Reddy, G.V.; Dinesh, P.M.; Sandhya, R.; Laha, K.; Jayakumar, T.
• Is Part Of: International journal of fatigue. Volume 92:Part 1(2016)
• Page Start: 272
• Page End: 280
• Publication Date: 2016-11
• Subjects: 321 stainless steel -- Low cycle fatigue -- Ratcheting -- S-N curve -- ASME fatigue curve; Materials -- Fatigue -- Periodicals; Materials -- Fatigue; Periodicals; 620.1122
• DOI: 10.1016/j.ijfatigue.2016.07.009
• Languages: English
• ISSNs: 0142-1123

Abstract

Graphical abstract: Highlights: 321 SS has shown ratcheting-strain accumulation even under zero mean-stress. Direction of ratcheting is strongly dependent on initial-ramp direction of 1st-cycle. Plastic-strain range and striation-width are lower in strain-controlled fatigue. S-N curve of present study is 2–3 orders of magnitude lower than ASME best-fit curve. Abstract: Cyclic deformation and fracture behavior of the 321 stainless steel are investigated at 633 K under engineering-stress and strain controlled low cycle fatigue (LCF) cycling, and the fatigue life data are compared with ASME section-III Division-1 S-N curve. In stress-controlled LCF tests, ratcheting-strain accumulation is observed even under zero mean-stress, and the direction of ratcheting is found to strongly depend on initial-ramp direction of first-cycle. In addition, plastic-strain range and striation width are observed to be higher than those in strain-controlled tests. The stress-life curve obtained from stress-controlled tests is 2–3 orders of magnitude lower in comparison to stress-life curve derived from strain-controlled LCF tests as per the ASME procedure. The discrepancy is attributed to the differences in deformation and damage development in stress and strain-controlled cycling.