75Cr1钢加热炉内表面脱碳分析

在实验室模拟现场加热炉加热过程,在CO_2、O_2、H_2O、N_2体积分数分别为16.5%、0.8%、13%、69.7%的混合气氛下对75Cr1钢加热保温。通过正交实验研究了加热温度(975、1 050、1 125、1 200℃)和保温时间(10、20、30、40min)对75Cr1钢脱碳的影响规律。并与菲克第二定律的计算结果进行了对比。实验结果表明:脱碳层深度随着加热温度和保温时间的增加而增加,并且当温度为1 200℃时,增幅明显变大;975℃时的实测值接近理论值,1 050、1 125、1 200℃时,实测值远小于理论值;扩散系数修正后计算值与实测值基本保持一致。

Analysis of surface decarburization of 75 Cr1 steel heating in furnace

According to the actual heating atmosphere environment,75Cr1 steel was heated in the experimental fur-nace with mixed atmosphere containing 16.5 vol% CO2 ,0.8 vol% O2 ,13 vol% H2 O,69.7 vol% N2 .The influ-ence of heating temperature (975,1 050,1 125 and 1 200℃)and holding time (10,20,30 and 40 min)on 75Cr1 steel decarburization were studied and experiment results were compared with the results calculated by the Fick′s second law.The experimental results show that the thickness of decarburization layer increases with increaseing the heat-ing temperature and holding time and growth rate gets maximum at 1 200℃.The measured values of decarburiza-tion layer are equal to the theoretical values at 975℃ and the measured values are far less than the theoretical val-ues at 1 050,1 125 and 1 200℃.The diffusion coefficient after correction is approximately equal to the measured values.