奥氏体化温度对3Cr3Mo2NiVNb钢组织和力学性能的影响  

Effect of Austenitizing Temperature on Microstructure and Mechanical Properties of 3Cr3Mo2NiVNb Steel

作　　者：胡春东[1] 曾斌 孟利[1] 董瀚[1] HU Chundong;ZENG Bin;MENG Li;DONG Han(Central Iron and Steel Research Institute,Beijing 100081,China;School of Materials Science and Engineering, University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]钢铁研究总院,北京100081 [2]北京科技大学材料科学与工程学院,北京100083

出　　处：《热加工工艺》2018年第22期234-236,247,共4页Hot Working Technology

摘　　要：利用SEM、TEM和高温共聚焦显微镜技术,研究了3Cr3Mo2NiVNb二次硬化钢不同奥氏体化温度下淬火的显微组织和力学性能。结果表明,在900~1000℃奥氏体化时,淬火组织中存在未溶碳化物,导致硬度偏低。在1000~1050℃,大部分碳化物溶解,晶粒长大,韧性缓慢下降,这说明MC型碳化物仍能有效抑制奥氏体晶粒的长大。在1050~1100℃,奥氏体晶粒迅速长大,韧性急剧减小,说明MC型碳化物已不能有效抑制晶粒的长大。随淬火温度升高,钢的淬火硬度增大,但淬火态与回火态硬度差值减小。The microstructures and mechanical properties of 3Cr3Mo2NiVNb secondary hardening steel at different austenitizing temperatures were studied by SEM,TEM and high temperature confocal microscopy.The results show that during austenitizing at 900-1000℃,there are some insoluble carbides in the quenched microstructure,which result in lower hardness.At 1000-1050℃,most of the carbides dissolve,the grain size grows and the toughness decreases slowly,which illustrates that the MC type carbides can effectively inhibit the growth of austenite grains.At 1050-1100℃,the austenite grains grow rapidly and the toughness decreases rapidly,which illustrates that MC type carbides can not inhibit effectively the growth of grain size.With the increase of quenching temperature,the quenching hardness of the steel increases,but the hardness difference value between quenched and tempered states decreases.

关 键 词：二次硬化钢 奥氏体化温度 碳化物 3Cr3Mo2NiVNb钢 

分 类 号：TG142-33[一般工业技术—材料科学与工程]