高碳铬轴承钢加热过程中氧化与脱碳特性分析  

Analysis on oxidation and decarburization of high-carbon chromium bearing steel in heating process

作　　者：史学星[1] 鞠新华[1,2] 蔡宁[1] 任群[1] 温娟[1] SHI Xue-xing JU Xin-hua CAI Ning REN Qun WEN Juan(Shougang Research Institute of Technology, Beijing 100043, China Beijing Engineering Research Center of Energy Steel, Beijing 100043, China)

机构地区：[1]首钢技术研究院,北京100043 [2]北京市能源用钢工程技术研究中心,北京100043

出　　处：《材料热处理学报》2017年第3期139-147,共9页Transactions of Materials and Heat Treatment

摘　　要：利用热重分析、金相及扫描分析等手段,研究了加热温度、保温时间和加热炉内气氛对高碳铬轴承钢GCr15氧化和脱碳行为影响。结果表明:随着加热温度和保温时间增加,GCr15钢氧化铁皮厚度和脱碳层深度均呈增大趋势;随着炉内含氧量增加,氧化铁皮厚度也呈增大趋势,但脱碳层深度呈下降趋势,且含氧量达6%脱碳趋于稳定。通过热力学和动力学分析发现:随着加热温度、保温时间以及炉内含氧量增大,其对应的抛物线氧化速率常数不断增大、高温抗氧化能力增强。低于900℃时,GCr15钢氧化增重与时间呈直线规律增长;高于900℃时,呈抛物线规律增长,其对应的氧化激活能由113.9 k J/mol增大到324.1 k J/mol,870℃为氧化机制发生改变的临界温度。Effects of heating temperature, holding time and furnace atmosphere on surface oxidation and decarburization of high-carbon chromium bearing steel GCrl5 were studied by means of thermogravimetrie analysis （TG） , optical microscope （OM） and scanning electrical microscopy（SEM）. The results show that with the increasing of heating temperature and holding time, the thickness of iron scale or the depth of decarburizatiou layer increases. With the increasing of furnace oxygen content, the thickness of the iron scale increases, but the depth of the decarburization layer decreases and keeps stable when O2 content is over 6%. The results of thermodynamics and kinetics show that with the increasing of temperature and time, the oxide parabolic rate constant and oxidation resistance increase. When the heating temperature is below 900 ℃ ,the oxidative mass increment of the GCrl5 steel exhibits a straight-line growth trend. While the temperature is over 900 ℃ , it exhibits a parabolic growth trend, and the activation energy value increases from 113.9 kJ/mol to 324. 1 kJ/mol. The temperature of 870 ℃ is the change point of oxidation.

关 键 词：热重分析仪 GCR15轴承钢 氧化脱碳 热力学 动力学 

分 类 号：TG142.4[一般工业技术—材料科学与工程] TG156.98[金属学及工艺—金属材料]