1. School of Materials Science and Engineering, Northeastern University, Shenyang 110819, Liaoning, China; 2. Central Research Institute, Baosteel, Shanghai 201900, China; 3. Liaoning Key Laboratory of Key Metal Structural Materials for Lightweight, Northeastern University, Shenyang 110819, Liaoning, China
Abstract：The scaling problem on the surface of hot-rolled or cold-rolled nickel-saving austenitic stainless steel affects the qualification rate of products seriously. The characteristics of solidification structure for BN1TL stainless steel were studied by BN1TL stainless steel continuous casting billet. The correlation between structure of continuous casting billet and the scale defect was verified by simulation test of hot rolling in cold charging furnace. It can be found from experimental results that the solidification structure of BN1TL stainless steel is mainly columnar crystals, and the grain size gradually increases from surface to core. The chromium carbide precipitation is observed in the grain boundary of columnar crystals, which leads to serious grain boundary weakening, therefore, the scale defects are easily to be produced during hot rolling and would affect the whole rolling process. The results of simulation show that the scale defect occurs during rough rolling and expanded during finish rolling. Reduce the pass reduction of rough rolling is a useful way to inhibit the production of scale defects and improve the quality of billet surface.
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2023, Vol. 33 
