大直径锻造钢磨球的淬透性  

Hardenability of large diameter forged steel grinding balls

作　　者：蒲以松 王宝奇[1] 宋孟超 张连贵 PU Yi-song;WANG Bao-qi;SONG Meng-chao;ZHANG Lian-gui(School of Materials Science and Engineerin;Hebei University of Technology,Tianjin 300130,China)

机构地区：[1]河北工业大学材料科学与工程学院

出　　处：《材料热处理学报》2018年第8期102-107,共6页Transactions of Materials and Heat Treatment

基　　金：邯郸市2016年科技计划产学研科技合作专项项目(1615104027)

摘　　要：针对直径在120 mm以上的大直径磨球,设计一种高碳低合金锻造磨球用钢,并对该钢所制磨球进行淬火试验以研究其淬透性。通过热膨胀仪测得该钢的临界点温度（Ac1）,采用洛氏硬度计测量磨球的硬度并使用光学显微镜观察磨球心部区域的显微组织。结果表明：末端淬火得到的实验结果与Grossmann方法计算所得淬透性结果相吻合;其中,870℃淬火后的磨球具有良好的淬透性,从表面到心部的硬度分布均匀,最大体积硬度可达61.7 HRC;该磨球组织主要由细小的混合马氏体组成,平均晶粒尺寸为15μm,晶粒度级别为8.4级,满足大直径锻造磨球的使用性能要求。For large diameter grinding balls with diameter more than 120 mm,a high carbon low alloy forged grinding ball steel was designed. The quenching test of the grinding ball made of the steel was carried out in order to study its hardenability. The critical temperature（ Ac1） of the steel was measured by thermal expansion test,the hardness of the grinding balls was measured by Rockwell hardness tester and the microstructure of the central zones of the grinding balls was observed by optical microscope. The results show that the experimental results obtained by Jominy end-quenching test are in good agreement with the results of the hardenability calculated by the Grossmann method. The grinding balls quenched at 870 ℃ have good hardenability,the hardness distribution from the surface to the center is uniform,and the maximum volume hardness can reach 61. 7 HRC. The microstructure of the grinding ball is mainly composed of fine mixed martensite with an average grain size of 15 μm and the grain-size grade of 8. 4,which meets the requirements of the performance of the large diameter forged grinding balls.

关 键 词：锻造钢磨球 淬透性 硬度 末端淬火试验 理想临界直径 

分 类 号：TG142.3[一般工业技术—材料科学与工程]