渗碳温度对22Si2MnCrNi2MoA钢渗碳层的影响  

Influence of carburizing temperature on microstructure and properties of carburized layers of a 22Si2MnCrNi2MoA steel

作　　者：黄斌[1,2] 朱洪武[1] 杨忠[1,2] 周乐育[1] 刘雅政[1] 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083 [2]西宁特殊钢股份有限公司,青海西宁810005

出　　处：《材料热处理学报》2013年第7期136-141,共6页Transactions of Materials and Heat Treatment

摘　　要：通过固体渗碳试验研究了加热温度对钎具用钢22Si2MnCrNi2MoA渗碳层的影响,分析了渗碳温度-碳浓度-显微硬度-残留奥氏体的关系以及残留奥氏体的控制措施。结果表明:当渗碳时间为6 h时,随着渗碳温度的升高,渗碳层的碳浓度逐渐增加,碳浓度分布梯度越来越平缓。22Si2MnCrNi2MoA钢渗碳层的显微硬度-碳浓度关系符合正态分布。在渗碳处理过程中,为了使渗碳表层获得硬度很高的马氏体组织,22Si2MnCrNi2MoA钢渗碳层表面碳浓度应该控制在0.80%～0.90%之间。当表面碳浓度超过0.80%～0.90%时,渗碳完成后需采取后续的工艺措施来消除已经存在的残留奥氏体,如采用长时间自然时效或深冷处理等。Influence of carburizing temperature on carburized layers of a 22Si2MnCrNi2MoA steel solid-carburized was studied by OM,SEM,XRD and hardness measurements.The relationship between carburizing temperature and carbon concentration,micro-hardness and retained austenite of the carburized layers were examined.The results indicate that with the carburizing temperature increasing for carburizing time of 6 h,the carbon concentration of the carburized layers gradually increases,and the distribution gradient of the carbon concentration gets smoother.The relationship between the micro-hardness of the carburized layers and carbon concentration obeys normal distribution.It is recommended that the surface carbon concentration of the carburized steel should be controlled in the range of 0.80% and 0.90% in order to obtain martensite microstructure with high hardness.When the surface carbon concentration is more than 0.80%-0.90%,aging treatment for a long time or deep cryogenic treatment are required to remove retained austenite in the carburized layers.

关 键 词：钎具用钢 22Si2MnCrNi2MoA 渗碳 残留奥氏体 加热温度 

分 类 号：TG156.8[金属学及工艺—热处理] TG142.45[金属学及工艺—金属学]