Abstract: Effect of Ca-Si modified treatment on morphology and ingredient of sulfide in steel 30MnVS (%:0.30~0.33C,1.40~1.60Mn,0.08~0.14V,0.065~0.090S) has been studied by optical microscope,scanning electron microscope and thermodynamic calculation. Results show that with increasing Ca content(0.0012%,0.0021%,0.0035% and 0.0046%)in steel,cluster rod-like sulfides gradually modify to dispersing globular sulfides,and most of sulfides have compound oxide core,the change sequence of its ingredient is CaO·3(Al₂O₃)·SiO₂-3(CaO)·6(Al₂O₃)·2(SiO₂)-6(CaO)·9(Al₂O₃)·4(SiO,)-4(CaO)·3(Al₂O₃)·2(SiO₂),and the results of calculation coincide with that of experiment analysis.

Key words: Free Cutting, Non-Quenched-Tempered Steel, Ca-Si Treatment, Compound Sulfde, Thermodynamic Analysis

摘要： 采用金相显微镜、扫描电镜和热力学计算,研究了Ca-Si变质处理对30MnVS钢(%:0.30～0.33C、1.40～1.60Mn、0.08～0.14V、0.065～0.090S)硫化物形貌和组成的影响。结果表明,随着Ca含量(0.001 2%、0.002 1%、0.003 5%、0.004 6%)的增加,团簇的杆状硫化物逐渐转变为均匀分散的球状硫化物,并且大多数球形硫化物中含有复合氧化物核心。其成分变化规律为CaO·3(Al₂O₃)·SiO₂-3(CaO)·6(Al₂O₃)·2(SiO₂)-6(CaO)·9(Al₂O₃)·4(SiO₂)-4(CaO)·3(Al₂O₃)·2(SiO₂),计算结果与实验分析结果基本吻合。

关键词: 易切削, 非调质钢, Ca-Si处理, 复合硫化物, 热力学分析