Mo含量对碳弧堆焊Fe-Cr-C-Mo-B耐磨层组织和性能的影响  

Effect of Mo Content on Microstructure and Wear Resistance of Fe-Cr-C-Mo-B Hardfacing Alloys Prepared by Carbon Arc Welding

作　　者：杨森[1] 王伟[1] 何平[1] 

机构地区：[1]辽宁工程技术大学矿业技术学院,辽宁葫芦岛125105

出　　处：《材料保护》2015年第1期47-48,51,共3页Materials Protection

摘　　要：目前，对Fe-Cr-C-Mo-B合金堆焊技术研究报道较少。采用碳弧焊方法，在Q235钢表面堆焊Fe-Cr-C-Mo-B合金层，采用金相显微镜、扫描电镜、X射线衍射仪分析了堆焊层的组织结构、形貌及成分。采用摩擦磨损试验研究了堆焊层的耐磨性，探讨了不同Mo含量对堆焊层组织和性能的影响。结果表明：Mo含量为0-2．5％（质量分数）时，堆焊层组织主要为亚共晶组织，Mo含量为4．0％时，组织中出现了少量大块状初生碳化物，有向过共晶转变的趋势；堆焊层组织主要为马氏体、铁素体、珠光体，碳化物主要为Cr7C3，Cr23C6以及B4C；随着Mo含量的增加，堆焊层的硬度增加，堆焊层的磨损失重呈减小趋势，Mo含量为4．0％时硬度达到最大值62．5HRC，磨损失重最小，堆焊层划痕最浅，耐磨性最好。Fe-Cr-C-Mo-B hardfacing alloys were prepared on Q235 steel substrate by carbon arc welding.The microstructure,morphology and composition of as-prepared Fe-Cr-C-Mo-B alloy coatings were analyzed by metallographic microscopy,scanning electron microscopy and X-ray diffraction.The wear resistance of the alloy coatings was evaluated with a friction and wear tester,and the effect of Mo content on the microstructure and wear resistance of the coatings was investigated.Results indicated that in the Mo content range of 0~2.5%(mass fraction;the same hereafter),the hardfacing alloys mainly consisted of hypoeutectic.When Mo content was 4.0%,a small amount of blocklike primary carbides emerged,and they tended to transform to hypereutectic.The hardfacing alloys were mainly composed of martensite,ferrite,and pearlite;and the carbides mainly included Cr_7C_3,Cr_(23)C_6 and B_4C.With the increase of Mo content,the hardness of the hardfacing alloys tended to rise,and it reached the maximum of 62.5 HRC at a Mo content of 4.0%.In the meantime,the wear mass loss of the hardfacing alloys tended to decline with increasing Mo content,and it reached the minimum of 8.8 mg at a Mo content of 4.0%.Particularly,the hardfacing alloy with 4.0%Mo exhibited the slightest scratching and the best wear resistance.

关 键 词：耐磨堆焊层 碳弧焊 Fe-Cr-C-Mo-B Mo元素含量 耐磨性 

分 类 号：TG455[金属学及工艺—焊接]