钼含量对高铬铸铁堆焊层组织及耐磨性的影响  

Effect of Mo content on microstructure and wear resistance of hardfacing layer of high chromium cast iron

作　　者：张凯 郭智 孙东云 李艳国 张明[1] ZHANG Kai;GUO Zhi;SUN Dongyun;LI Yanguo;ZHANG Ming(State Key Laboratory of Metastable Materials Science and Technology,Yanshan University,Qinhuangdao 066004,Hebei,China;Seventh Port Branch,Qinhuangdao Port Co.,Ltd.,Qinhuangdao 066003,Hebei,China;School of Metallurgy and Energy,North China University of Science and Technology,Tangshan 063210,Hebei,China)

机构地区：[1]燕山大学亚稳材料制备技术与科学国家重点实验室,河北秦皇岛066004 [2]秦皇岛港股份有限公司第七港务分公司,河北秦皇岛066003 [3]华北理工大学冶金与能源学院,河北唐山063210

出　　处：《钢铁》2024年第4期148-158,178,共12页Iron and Steel

基　　金：国家自然科学基金资助项目(52122410,51831008);河北省高等学校科学技术研究资助项目(KJZX202203);河北省高等学校科学技术研究资助项目(科技重大专项)(KJZX202203)。

摘　　要：高铬铸铁堆焊层因其较高的耐磨性而广泛应用于各种大型工业设备的内部衬板,研究发现Mo系碳化物可为初生碳化物的生成提供形核点从而细化组织,但Mo元素除了提供形核点外是否对组织存在别的作用仍尚待研究。为了研究Mo含量对高铬铸铁堆焊层组织与性能的影响,设计了一种含Mo超高碳高铬堆焊耐磨板,利用XRD、SEM分析了Mo元素对堆焊层组织、相组成以及磨损后堆焊层表面和纵截面的影响,利用EDS分析了元素在各相中的分配情况,并进一步利用硬度和干砂磨料磨损试验,研究了Mo合金化对高铬高碳堆焊层硬度和耐磨性的影响。结果表明,Fe-Cr-Mo-C合金堆焊层组织主要由γ相、M_(7)C_(3)(M=Fe、Cr)组成。随着Mo含量的提高,堆焊层内初生碳化物含量降低,奥氏体含量增加,单个初生碳化物尺寸先减小后增大;初生碳化物硬度增加,堆焊层宏观硬度先增加后降低;磨损后初生碳化物截断裂纹减少,剥落逐渐减少,其中30Mo试样出现了共晶碳化物的剥落。加入0.13%Mo后磨损失重减少了13.6%,加入0.30%Mo后磨损失重增加了20.0%。这是因为Mo原子的加入会提高初生碳化物的硬度,但是初生碳化物含量在减少,从而导致了堆焊层硬度先升高后降低,磨损失重量先减小后增大。研究结果对高铬铸铁堆焊层制备过程中选择适宜的Mo添加量提供了指导。试验设计了Mo质量分数为0.04%~0.30%的3个试样,结果表明,初生碳化物出现了先细化后粗化的趋势,对这部分变化的趋势还有待进一步细化研究。The high chromium cast iron surfacing layer is widely used in the internal lining of various large industrial equipment due to its high wear resistance.It is found that the carbide formed by the Mo element can provide core points for the primary carbides to refine the structure.However,whether the Mo element plays other roles besides providing core points remains to be studied.To investigate the influence of Mo content on the organization and performance of the high chromium cast iron surfacing layer,Mo ultra-carbon high chromium surfacing wear-resistant plate was designed.The effect of the Mo element on the structure and phase composition of the surfacing layer,as well as the surface and longitudinal section of the wear surfacing layer,is analyzed using XRD.The distribution in each phase,and further using the hardness and dry sand abrasive wear test,the influence of Mo alloying on the hardness and wear resistance of high chromium and high carbon surfacing layer was studied.The results indicate that the structure of the Fe-Cr-Mo-C alloy surfacing layer mainly consists of the gamma phase and M_(7)C_(3)(M=Fe,Cr).With the increase of Mo content,the primary carbide content in the surfacing layer decreases,the austenite content increases,and the size of a single primary carbide decreases first and then increases.The hardness of the primary carbide increases,and the macroscopic hardness of the surfacing layer increases and then decreases;after wear,the truncated pattern of the primary carbide decreases,and the sample showed the peeling of eutectic carbide.After adding 0.13%Mo,the grinding loss weight was reduced by 13.6%,and after adding 0.30%Mo,the grinding loss weight increased by 20.0%.This is because the inclusion of Mo atoms increases the hardness of the primary carbide,but with the content of primary carbides decreasing,it results in an initial increase and then a decrease in the hardness of the surfacing layer and a corresponding variation in grinding loss weight.The research results provide guidance for selecti

关 键 词：Fe-Cr-C合金 堆焊 Mo合金化 耐磨性 M7C3碳化物 

分 类 号：TG455[金属学及工艺—焊接]