加热温度对高钒高速钢中M2C碳化物分解转变行为的影响  

Effect of Heating Temperature on Decomposition Transition Behavior of M2C Carbide in High-vanadium High-speed Steel

作　　者：曹玉龙 张赛康 汪秀秀 马崇圣 李光强[1,2] Cao Yulong;Zhang Saikang;Wang Xiuxiu;Ma Chongsheng;Li Guangqiang(Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,Wuhan University ofScience and Technology,Wuhan 430081,China;The State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan,430081 China;Technical Center ofDongfeng Commercial VehicleCo.,Ltd.,Wuhan 430056,China)

机构地区：[1]武汉科技大学钢铁冶金及资源利用省部共建教育部重点实验室,武汉430081 [2]武汉科技大学省部共建耐火材料与冶金国家重点实验室,武汉430081 [3]东风商用车有限公司技术中心,武汉430056

出　　处：《特殊钢》2024年第4期146-152,共7页Special Steel

基　　金：湖北省自然科学基金资助项目(2023AFB654);钢铁冶金及资源利用省部共建教育部重点实验室拔尖人才培育项目(FMRUlab202306)。

摘　　要：基于高耐磨性的需要,设计了一种W3Mo4Cr5V6高钒高速钢,利用SEM、EMPA等手段对该钢高温加热过程亚稳态M_(2)C碳化物的分解转变行为进行了分析。结果表明,共晶碳化物M_(2)C在高温加热过程会发生M_(2)C+γ-Fe→M_(6)C+MC+M_(7)C_(3)的转变,在富Mo、W的M_(2)C相周围形成了大量富W、Mo的M_(6)C及少量富V的MC和富Cr的M_(7)C_(3)。随着温度由950℃增至1150℃,M_(2)C高温转变逐渐趋于完全,且纤维状M_(2)C比层片状M_(2)C更易分解转变,最终,由呈断续网状分布于奥氏体晶界的层片或纤维状形貌向零星分布于晶界的颗粒状形貌过渡,可有效减少网状碳化物对晶界的危害。研究可为高速钢中晶界碳化物成分、形态控制及其热加工、热处理过程温度与时间等参数选择提供有效参考。Based on the need of high wear resistance,a new kind of high-vanadium high-speed steel named W3Mo4Cr5V6 was designed.The transformation behavior of metastable M_(2)C carbides in the high temperature heating process of the steel was analyzed by means of SEM and EMPA.The results show that the cophortic M_(2)C carbide will undergo M_(2)C+γ-Fe→M_(6)C+MC+M_(7)C_(3) transition at high temperature heating process.A large number of W,Mo-rich M_(6)C and a small amount of V-rich MC and Cr-rich M_(7)C_(3) are formed around the Mo and W-rich M_(2)C phase.With the increase of temperature from 950℃to 1150℃,the high temperature transformation of M_(2)C carbides gradually tends to be complete and the fibrous M_(2)C is easier to decompose and transform than lamellar M_(2)C,and the lamellar or fibrous morphology distributed in the austenite grain boundary with discontinuous network is transformed into the granular morphology distributed at the grain boundary,which can effectively reduce the harm of network carbides to the grain boundary.The research can provide an effective reference for the composition and morphology control of carbides distributed at the grain boundaries of high-speed steel and the optimal selection of parameters such as temperature and time of hot processing and heat treatment process.

关 键 词：高速钢 电渣重熔 M2C碳化物 高温转变 成分分析 

分 类 号：TG161[金属学及工艺—热处理]