Effect of casting parameters on the freezing point position of the 304 stainless steel during twin-roll strip casting process by numerical simulation

Abstract

This study focuses on the numerical simulation of the temperature fields of the 304 stainless steel during twin-roll strip casting process. The cracks and fratographs of the 304 stainless steel strip with the practical casting parameters were observed by Scanning Electron Microscopy. The exit temperature of the 304 stainless steel during twin-roll strip casting process was measured. Meanwhile, it was simulated by means of finite element model. The observed results show that the strip from outside to inside are composed of refined crystal zone, columnar crystal one, and equated axis crystal one. The cracks occur on the strip surface, extended to interior along the columnar crystal boundary, and then, ended at the juncture between the columnar crystal zone and equated axis crystal one. The simulated result was compared to the measured temperature, which showed a good agreement, thus indicating that this model is valid and accurate. Then, by employing this model, the effects of the casting parameters, such as casting speed and casting temperature, on the freezing point position of the 304 stainless steel during twin-roll strip casting process were simulated too. The simulated results show that, the freezing point position is decreased with the increasing casting speed and casting temperature. For producing high-quality strip of 304 stainless steel during twin-roll strip casting, the limits of casting speed and casting temperature are 1.1 m·s⁻¹ and 1,570 °C, respectively.