Creep Curve Modeling to Generate the Isochronous Stress-Strain Curve of Type 316LN Stainless Steel
An isochronous stress-strain curve (ISSC) needs to be generated for a creep design application for high-temperature materials. To generate the ISSC for type 316LN stainless steel (SS), a series of creep data, which was obtained from creep tests with different stress levels at 600oC, was used. Creep curves were modeled by means of a nonlinear least square fitting (NLSF) of the Garofalo model. In the fitting of the creep curve, a secondary creep region was separated into first and second phases, and its fitting range was suitable to use for the first phase. The Garofalo model revealed a good agreement with the experimental creep data, and its parameters, P1, P2 and P3 revealed a good linear relationship as a function of a stress. The ISSCs for type 316LN SS at 600oC were successfully generated up to 300,000 hours.
H.S. Lee, I.S. Yoon and M.H. Aliabadi
S. N. Yin et al., "Creep Curve Modeling to Generate the Isochronous Stress-Strain Curve of Type 316LN Stainless Steel", Key Engineering Materials, Vols. 385-387, pp. 705-708, 2008