Session: DA-04-01 Inelastic, Nonlinear, and Limit Load Analysis

Paper Number: 60525

Start Time: Tuesday, July 13, 2021, 08:00 PM

60525 - Cyclic Stress-Strain Curve of Austenitic Stainless Steels Applicable to Elastic-Plastic Stress Analysis 

In the ASME B&PV Code Section III, XIII-3440 SHAKEDOWN ANLYSIS of Appendix XIII allows to use elastic-plastic stress analysis for evaluating shakedown and fatigue analysis. However, Appendix XIII does not specify any stress-strain curve for this evaluation. A cyclic stress-strain curve is needed for shakedown and fatigue analysis using elastic-plastic stress analysis.

Hence, cyclic stress-strain curves of austenitic stainless steels are proposed in this paper.

To develop cyclic stress-strain curves, many fatigue data are needed, and the applicable fatigue data of 316 stainless steel have been collected from several Japanese reports. The specimen types were hollow cylindrical specimens and round bar specimens. Those tests were performed by strain-controlled testing. The range of strain amplitudes were from 0.1 % to around 1.0 %. The temperature of the tests were room temperature and high temperature (100 – 325 °C). The environments of the tests were in air and in PWR water environment.

Two types of relationship were employed. One is power law type and the other is Ramberg-Osgood type. Those relationships were converted to bilinear type relationships with considering appropriate margin.

On the other hand, the ASME B&PV Code Section III does not specify any cyclic stress-strain curve, but the ASME B&PV Code Section VIII Division 2 has Annex 3-D that specifies cyclic stress-strain curves. Annex 3-D does not have the cyclic stress-strain curve data of 316 stainless steel but has those of 304 stainless steel. Therefore, the developed cyclic stress-strain curves are compared with those of 304 stainless steel in Annex 3-D.

Presenting Author: Seiji Asada Mitsubishi Heavy Industries, Ltd

Authors:

Seiji Asada Mitsubishi Heavy Industries, Ltd
Yuichiro Nomura Mitsubishi Heavy Industries, Ltd