Distribution characteristics of oxides and sulfide inclusions in key areas of gear steel forgings
LI Lan-xin,WANG Min,JUAN Rong-fei,BAO Yan-ping,YANG Jin
1.State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China；2.Beijing National Railway Research and Design Institute of Signal and Communication Group Co., Ltd., Beijing 100070, China
Abstract：Abstract：Gears are key structural components of mechanical transmission. In order to improve the service performance of gears and improve the fatigue life, it is necessary to know the type, quantity, size and distribution of inclusions in gear steel. Inclusions were evaluated at different positions of gear steel forgings using an automatic inclusion scanner, oxygen content analysis method, and scanning electron microscope. The total oxygen content in the center of the casting is higher, which is 10×10-6, corresponding to the large number of smallsized inclusions, and the largesized inclusions are distributed in key areas. The oxide inclusions in the steel are mainly Al2O3, Al2O3 composite spinel and calcium aluminate composite inclusions, and the size is large and the distribution is uneven, which has a greater impact on the key areas of gear steel. The distribution of sulfide inclusions in the steel is uniform and the size is small. Thermodynamic calculations show that MnS begins to precipitate when the solidification rate g>0.44 during the solidification process. By controlling the precipitation and distribution of sulfide inclusions, it helps to improve the quality of gear steel.
李岚昕1，王敏1，隽荣斐1，包燕平1，阳晋2. 齿轮钢锻件关键区域氧化物和硫化物夹杂的分布特征[J]. 钢铁研究学报, 2020, 32(5): 370-376.
LI Lan-xin1,WANG Min1,JUAN Rong-fei1,BAO Yan-ping1,YANG Jin2. Distribution characteristics of oxides and sulfide inclusions in key areas of gear steel forgings. JOURNAL OF IRON AND STEEL RESEARCH , 2020, 32(5): 370-376.