热穿-热轧法生产的新型贝氏体中空渗碳钢的组织和性能

Microstructure and Properties of New Type Bainitic Hollow Carburizing Steels Manufactured by Hot-Penetrating and Hot-Rolling Method

用热穿-热轧法制备了新型贝氏体中空钢.研究了热处理对新型贝氏体钢和渗碳处理对中空钢组织和性能的影响.结果表明:新型贝氏体钢正火+低温回火热处理后的组织为贝氏体铁素体和奥氏体,淬火+低温回火后的组织由马氏体、贝氏体和奥氏体组成;正火或淬火+低温回火后,新型贝氏体中空钢具有良好的强韧性.正火+低温回火后,中空钢的组织为贝氏体铁素体和残余奥氏体组织.新型贝氏体中空钢渗碳后空冷,渗层的组织为高碳马氏体和残余奥氏体组织,非渗层为贝氏体铁素体和残余奥氏体组织,实体中空钢具有较好的强韧性和渗碳效果.

A new type bainitic hollow steels were fabricated by hot-penetrating and hot-rolling method. The influences of heat treatment on the microstructure and properties of new type bainitic steel and carburizing treatment on the microstructure and properties of the hollow steels were studied. The results showed that the new type bainitic steels with bainite ferrited and retain austenite were obtained at normalizing and low temperature tempering and the new type bainitic steels with the microstructure of martensite, bainite and retain austenite were obtained at quenching and low temperature tempering. They both have better strength and impact toughness. The microstructure of new type bainitic hollow steel were bainited ferrite and remained austenite after normalizing and low temperature tempering and has better strength and impact toughness. After carburized and air-cooled, The microstructure of bainite ferrite and retain austenite in the matrix and high carbon martensite and retained austenite in carburized layer were acquired and they made the hollow steel possess excellent strength and toughness and carburiztion effect.