A Generalized Temperature‐Modified Smith–Watson–Topper Model for Low‐Cycle Fatigue Life Prediction Over a Wide Temperature Range

ABSTRACT

A temperature‐modified Smith–Watson–Topper (TM‐SWT) model applicable over a wide temperature range is proposed in this study. First, low‐cycle fatigue (LCF) tests were conducted on high silicon molybdenum nodular cast iron (QTRSi4Mo1). Subsequently, model parameters were identified by combining different multiobjective optimization algorithms with various objective functions, and the predictive performances of the Manson–Coffin–Basquin (M‐C‐B) and Smith–Watson–Topper (SWT) models were systematically compared. Based on the correlation between the SWT model parameters and temperature, the TM‐SWT model was developed and applied to fatigue life prediction. The results show that the TM‐SWT model significantly improves the prediction accuracy of QTRSi4Mo1 under wide temperature conditions. Finally, the proposed model was further applied to the LCF life prediction of compacted graphite cast iron (CGI) and still exhibited clear predictive advantages. Therefore, the TM‐SWT model demonstrates superior predictive capability and good generality for LCF life prediction over a wide temperature range.