等离子弧堆焊高铬铁基合金的组织形成机制及对显微硬度的影响  

Formation mechanism of microstructure of PTA surfacing high chromium Fe-based alloy and its effect on microhardness

作　　者：宗琳[1] 徐俊尧 王学钊 周建 杨洋[1] 王明 ZONG Lin;XU Junyao;WANG Xuezhao;ZHOU Jian;YANG Yang;WANG Ming(School of Mechanical and Power Engineering,Shenyang University of Chemical Technology,Shenyang 110142,Liaoning pro.,China;China Construction Industrial&Energy Engineering Company,Shenyang 110142,Liaoning pro.,China)

机构地区：[1]沈阳化工大学机械与动力工程学院,辽宁沈阳110142 [2]中建安装集团有限公司,江苏南京210000

出　　处：《焊接技术》2023年第1期17-21,I0007,共6页Welding Technology

基　　金：国家自然科学基金青年基金(51901141);辽宁省教育厅科学研究项目(LJ2020034)。

摘　　要：采用等离子弧堆焊的方法制备不同Cr含量的Fe-Cr-V-C堆焊层,分析了不同Cr含量对亚共晶、共晶和过共晶堆焊层M_(7)C_(3)尺寸与形态及性能的影响规律。通过SEM,EDS,XRD分析了堆焊层的显微组织及相组成,采用显微硬度计进行了硬度测试。结果表明:堆焊层组织由马氏体、奥氏体、M_(3)C,V_(2)C,共晶及初生M_(7)C_(3)组成;随着Cr含量的增多,共晶M_(7)C_(3)的数量逐渐增多,当w(Cr)超过10.10%后,堆焊层组织中开始出现初生六边形M_(7)C_(3),且数量逐渐增多;w(Cr)达到14.15%时,初生高硬度M_(7)C_(3)数量最多,且颗粒适中,形态分布均匀,使得堆焊层顶端显微硬度平均值最高,达到HV_(0.2)1 285。A series of Fe-Cr-V-C surfacing alloys with different Cr contents were prepared by plasma arc surfacing. The effects of addition amount of Cr on size, morphology and properties of hypoeutectic, eutectic and hypereutectic surfacing layers were studied. SEM, EDS and XRD were used to analyze the microstructure of the surfacing layer and the microhardness was tested. The results showed that the microstructure of surfacing layers were composed of martensite, austenite, M_(3)C, V_(2)C, eutectic M_(7)C_(3) and primary M_(7)C_(3). With the increase of Cr content, the number of eutectic M_(7)C_(3) gradually increased. When the Cr content exceeded 10. 10%, primary hexagonal M_(7)C_(3) begun to appear in the surfacing layer structure, and the number gradually increased. The highest microhardness on the top of the surfacing layer was up to HV0. 21 285 as the result of the microstructure characteristic with largest number and moderate size M_(7)C_(3) were distributed uniformly in the matrix as the Cr content was 14. 15%.

关 键 词：等离子弧堆焊 显微硬度 组织 Fe-Cr-V-C系 

分 类 号：TG456.2[金属学及工艺—焊接]