Research on the Influence of Compressive Stress and Temperature on the Compressive-Resilience Properties of Stainless Steel

The integrity of sealing systems in key energy and chemical industry equipment heavily depends on flange gaskets. In practice, complex operating conditions compromise the compressive-resilience behavior of flange gaskets, a process that may perhaps culminate in sealing failure. Therefore, this study conducted hot compression experiments on 304 austenitic stainless steel, aiming to investigate the effects of compressive stress and temperature on the compressive-resilience properties of gaskets. The experiments were performed with applied compressive stresses of 35, 50, and 65 MPa at temperatures of 100, 300, and 500 °C. The results indicate that under a compressive stress of 65 MPa at 500 °C, the specimen exhibits a maximum compression rate of 9.84% and a minimum resilience rate of 22.17%. Based on microstructural analyses, the underlying mechanisms are elucidated. The elastic compression stage is primarily governed by Hooke’s law, where greater compressive stress leads to increased deformation, and higher temperatures result in a lower elastic modulus, which in turn contributes to greater deformation. Unexpectedly, the compressed specimen failed to resilience completely. This is mainly because compressive stress leads to work hardening, plastic deformation, and phase transformation, while the temperature increase further induces plastic deformation, collectively weakening the material’s elastic recovery. Thus, it can be classified as quasi-elastic compression by strict definition.