Nb微合金元素对渗碳轴承钢组织和性能的影响
Effect of Nb microalloy elements on the structure and properties of carburized bearing steel
白雨鑫 1牟家林 1肖佳 1王金国1
作者信息
- 1. 东北特殊钢集团股份有限公司,辽宁大连 116000
- 折叠
摘要
为了研究控制渗碳轴承钢奥氏体晶粒长大的方法,采用模拟渗碳法晶粒度检验方式,930℃分别保温1h、3h和6h,对比研究含铌与不含铌的20Cr钢在不同保温时间下的奥氏体晶粒尺寸.结果表明,渗碳温度为930℃时,添加0.026%的铌能有效抑制20Cr钢奥氏体晶粒长大的倾向,适宜渗碳时间为1h和3h,随着保温时间的延长,奥氏体晶粒尺寸逐渐增大,6 h出现明显混晶.加入铌元素可以得到铁素体更为细小的组织,在930℃渗碳处理时,奥氏体晶界析出物主要为NbC和少量的TiN.相同渗碳条件下,添加铌能提高不同渗碳时间下,20Cr试样的显微硬度,在6h时达到最大硬度差53 HV.
Abstract
In order to study the method of controlling the growth of austenite grains of carburized bearing steel,the simulated carburization method was adopted,and 930℃was insulated for 1 h,3 h and 6 h respectively,and compared the size of austenite grains with niobium and without niobium at different insulation times.The re-sults show that when the carburization temperature is 930℃,the addition of 0.026%niobium can effectively in-hibit the tendency of austenite grains of 20Cr steel,and the suitable carburization time is 1 h and 3 h.With the ex-tension of the insulation time,the grain size of austenite gradually increases,and the obvious mixed crystal appears at 6 h.The addition of niobium can obtain the smaller tissue of ferrites.In 930℃carburization treatment,Nb,Ti in austenite are precipitate in the form of NbC and TiN.Under the same carburization conditions,the addition of ni-obium can improve the microhardness of 20Cr sample under different carburization times,and reach the maximum hardness difference of 53 HV at 6 h.
关键词
20Cr渗碳轴承钢/微合金元素/晶粒细化/硬度Key words
20 Cr carburized bearing steel/microalloy element/grain refinement/hardness引用本文复制引用
出版年
2024
NETL
NSTL
万方数据