等温淬火温度对低碳低合金奥贝铸钢组织和力学性能的影响  

Influence of Austempering Temperature on Microstructure and Mechanical Properties of LALC Austenitic-bainitic Cast Steel

作　　者：李洪波[1] 金宝士[1] 刘向东[2] 于峰[1] 

机构地区：[1]佳木斯大学材料学院,黑龙江佳木斯154007 [2]内蒙古工业大学材料学院,内蒙古呼和浩特010051

出　　处：《铸造技术》2007年第7期940-943,共4页Foundry Technology

基　　金：黑龙江省教育厅科技项目资助(项目编号:10541225)

摘　　要：研究了等温温度对低碳低合金奥氏体-贝氏体铸钢组织和力学性能的影响。结果表明,在280℃时,组织由细针状下贝氏体、残余奥氏体和少量马氏体组成;在300℃时,得到完全由贝氏体铁素体和富碳残余奥氏体组成的奥贝组织,无碳化物相,硬度稍有下降,冲击韧度大幅度提高,此时综合性能最佳;在320℃贝氏体逐渐分成枝叉状,360℃时,形成带有羽毛状的上贝氏体组织,冲击韧度进一步提高,但硬度较低,材料的综合性能较差。The influence of austempering temperature on the microstructure and mechanical properties of low-alloy and low carbon （LALC） austenitic-bainitic cast steel was investigated. The results show that the microstructure consists of fine acicular bainite, retained austenite and few martensite at 280 13, and a pure ausferrite structure consists of typical bainitic ferrite and carbon- rich retained austenite without carbide at 300 13. The hardness of the steel decreases slightly and impact toughness increases sharply with increase of the isothermal temperature. The optimal mechanical properties can be obtained at 300 13. The morphology of bainite gradually changes from fork shape to feather upper bainite when temperature increases from 320 ℃ to 360℃, and the toughness further increases, but the hardness decreases, the combination of properties is poor.

关 键 词：低碳低合金奥氏体-贝氏体铸钢 力学性能 显微组织 

分 类 号：TG156.3[金属学及工艺—热处理] TG142.1[金属学及工艺—金属学]