Performance and microstructural evolution of 304 stainless steel after fire-induced ablation

This paper focuses on the mechanical performance degradation and microstructural evolution of 304 stainless steel used for elevator landing doors after high-temperature ablation in a fire. By simulating a fire environment and combining it with fire resistance testing standards, the mechanical properties of 304 stainless steel after a fire were evaluated, and its microstructural changes were observed. Research has found that high temperatures caused by fires lead to the occurrence of α-Fe phase transition in materials, resulting in the formation of oxides on the surface and oxidation delamination; The strength and plasticity of the material decrease with erosion time, the surface hardness significantly deteriorates, and the corrosion resistance of the material deteriorates. In addition, this study established an empirical formula between microstructural changes and mechanical properties based on material microstructural changes, providing theoretical guidance for the evaluation of elevator door materials and fire-resistant design.