Comparison of Cleanliness Wear-resistant Steel at Home and Abroad

Author of the article:ZHANG Hao 1 ， 2 ， 3 , WANG Dong 4 , LUN Mingrui 1 ， 2 ， 3 , FU Jianxun 1 ， 2 ， 3 , SHEN Ping 1 ， 2 ，

Author's Workplace：1. School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China; 2. Center for Advanced Solidification Technology, Shanghai University, Shanghai 200444, China; 3. State Key Laboratory of Advanced Special Steel, Shanghai University, Shanghai 200444, China; 4. Angang Steel Co., Ltd., Anshan 114033, China

Key Words： wear-resistant steel; inclusions; Ca-treatment; cleanliness

Abstract： Inclusions in wear-resistant steel are important factors that affect the strength, toughness and other properties of wear-resistant steel. To analyse the control level of inclusions in wear-resistant steel at home and abroad, the size, distribution and composition of inclusions and the steel matrix hardness of wear-resistant steel from Japan and China were analysed. The results show that the size of inclusions in factory A is similar to that of the Japanese wear-resistant steel, but the density of inclusions is higher, which leads to the cleanliness being slightly lower than that of japanese wear-resistant steel. The inclusions in Japanese steel are mainly CaO, CaO-Al2O3 , MgO-Al2O3 , MgO-Al2O3 -CaO and TiN, Ti(C,N). The precipitation of MnS in steel decreases and the contents of CaS and CaO in inclusions increase by Ca-treatment in the factory A. However, MnS is found to precipitate in the wear-resistant steel of factory B domestically. According to the
hardness analysis of each factory, the average hardness of the Japanese wear-resisting steel matrix is 447 HV, and the hardness distribution is uniform. The hardness of domestic factories A and B is slightly lower than that of Japanese wear-resistant steel, and both have uneven hardness distributions. There is still a gap between the domestic products and Japanese products in terms of microstructure control level.