.
李松原，赵增武，李永治
(内蒙古科技大学内蒙古自治区白云鄂博矿多金属资源综合利用重点实验室，内蒙古包头014010)
关键词:U71Mn 钢;脱碳;碳扩散;动力学
中图分类号:TG142. 41 文献标识码:A
摘要:为了研究U71Mn 重轨钢在氧气中的高温脱碳规律，对U71Mn 重轨钢进行了氧气中950,1 050,1150 和1
250
℃
等4 个不同温度条件下的恒温30，60，90，120 min 的加热，通过金相法检测了上述条件下的脱碳层深度，在考虑碳扩散和氧化后，进行了脱碳动力学计算. 结果表明:在氧气气氛下，U71Mn 钢在950 ～ 1 150 ℃温度加热时，脱碳层深度随温度升高而逐渐增加，超过1 150 ℃以后，脱碳层深度逐渐减小，1 150 ℃时脱碳层深度最深. 在950 ～ 1
150
℃
，碳原子的扩散长度与加热时间的平方根成线性关系，扩散激活能为87． 41 kJ /mol.
Ｒesearch on decarburization of U71Mn steel under
high-temperature oxygen
LI Song-yuan，ZHAO Zeng-wu，LI Yong-zhi
(Key laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Ｒesources，Inner Mongolia University of Science and Technology，
Baotou 014010，China)
Key words:U71Mn steel; decarburization; carbon diffusion; kinetics
Abstract:The U71Mn steel under high-temperature oxygen medium was studied using experiments at temperatures of 950，1 050，1 150，1
250
℃
for 30 ，60 ，90 ，120 min，respectively，to obtain its decarburization characteristics． The depth of decarburization layer was detected and the decarburization kinetics was calculated by metallographic method in consideration of factors like carbon diffusion and oxidation． The results show that the depth of decarburization layer increases gradually with increasing the temperature with U71Mn steel being heated at 950 ～ 1
150
℃
; the layer depth gradually decreases when the temperature is over 1
150
℃
，and there is
the largest depth of decarburization layer at 1
150
℃
． When U71Mn steel is heated at 950 ～ 1
150
℃
，there is a linear relationship between carbon atom diffusion length and square root of heating time; the diffusion activation energy is identified as 87. 41 kJ /mol．
