Elevated temperature effects on erosion damage in Q235 mild steel subjected to silicon particle impingement

Abstract

Understanding the erosion of industrial equipment caused by high-temperature silicon particles impingement is essential for ensuring pipeline integrity in silicone production. In this study, a high-temperature gas–solid erosion platform was developed to investigate the erosive behaviour of Q235 mild steel under varying particle velocities, particle sizes, impact angles, and temperatures (100–500 °C). The evolution of surface morphology was characterised by scanning electron microscopy (SEM), which revealed distinct temperature-dependent erosion mechanisms, including plastic deformation, micro-cutting, and crack propagation. Existing erosion models, however, do not account for silicon particle abrasives and neglect the influence of temperature on the erosion behaviour of the target material. The model in this study is based on the structure of the Oka model, with the incorporation of a temperature-dependent term and corresponding coefficient modifications. Experimental results show that the vertical erosion rate decreases with increasing particle size, while the velocity exponent exhibits a U-shaped dependence on temperature and the particle size exponent follows a single-peak trend. The temperature dependence of erosion is further described by a nonlinear softening function, and the maximum erosion rate occurs at an impact angle of 40°. Based on these findings, a predictive high-temperature erosion model was constructed using genetic algorithms, integrating both silicon particle properties and the softening behaviour of Q235 mild steel.