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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。
The effects of heating temperature, holding time and atmosphere in heating furnace on the oxidation and decarburization behavior of high carbon chromium bearing steel GCr15 were studied by means of thermogravimetry, metallography and scanning analysis. The results show that with the increase of heating temperature and holding time, the thickness of the scale and decarburization depth of GCr15 steel increases. With the increase of oxygen content in the furnace, the thickness of the scale also increases. However, the thickness of the decarburized layer Depth showed a downward trend, and oxygen content of 6% decarburization tends to be stable. The results of thermodynamics and kinetics show that with the increase of heating temperature, holding time and the oxygen content in the furnace, the corresponding parabolic oxidation rate constant increases and the oxidation resistance at high temperature increases. When the temperature was below 900 ℃, the weight gain of GCr15 steel increased linearly with time. When the temperature was above 900 ℃, the oxidation of GCr15 increased parabolically and the corresponding oxidation activation energy increased from 113.9 kJ / mol to 324.1 kJ / mol. 870 ℃ for the oxidation mechanism changes the critical temperature.