Effect of laminar cooling process on microstructure and properties of NM300TP hot-rolled wear-resistant steel
LI Guan-nan1,2, HUANG Yan3, Lv De-wen1, PEI Qing-tao1
1. Technical center, Handan Iron and Steel Group Co., Ltd., Handan 056015, Hebei, China;
2. School of Materials Science and Engineering, Chongqing University, Chongqing 400044, China;
3. School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
In order to explore the best cooling process of NM300TP hot-rolled wear-resistant plate, the rolling plates under different cooling processes were obtained by controlling the intermediate cooling temperature and air-cooling time using a two-stage cooling process. The rolling plate has a three-phase structure of bainite + ferrite + retained austenite, and good comprehensive mechanical properties can be obtained without post-rolling heat treatment. The results demonstrate that the content of each phase in the wear-resistant steel has an obvious corresponding relationship with its mechanical properties. The more bainite is, the greater the Brinell hardness and tensile strength are, and the lower the wear loss is, but it has little effect on the plasticity of wear-resistant steel. The content of each phase can be adjusted through the cooling process, and a higher intermediate cooling temperature can inhibit ferrite transformation and promote the formation of bainite. The extension of air-cooling time is conducive to the formation of bainitic ferrite, and more bainite structure can be obtained in the secondary cooling process.
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