Fe-Cr-C系堆焊层中碳化物对耐磨性能的影响

Effect of Carbides in Fe-Cr-C Surfacing Layer on the Wear Resistance of the Layer

为研究Fe-Cr-C系堆焊层中碳化物形貌、分布、含量及硬度对耐磨性的影响,通过堆焊的方式在Q355B板上制备Fe-Cr-C系堆焊层,采用MLGS-225C型干湿橡胶轮磨粒磨损试验机,对比不同化学成分的Fe-Cr-C系堆焊层的耐磨性能。通过DM2700M型光学显微镜、 EM3-AX^(+)电子显微镜(SEM)观察显微组织,采用AZtecone XT型EDS分析材料成分、Wilson R574型洛氏硬度计测试试样的硬度。结果表明:2号试样堆焊层的耐磨性最好,这主要是因为2号试样中碳化物含量最高,且柱状、块状初生碳化物分布均匀,碳化物垂直于基材生长,可有效保护基体,降低磨损损失量,从而提升堆焊层耐磨性。

With the aim of studying the effect of the morphology, distribution, content and hardness of carbides in Fe-Cr-C surfacing layer on the wear resistance of the layer, Fe-Cr-C surfacing layers were prepared on Q355 B plates by surfacing welding. The wear resistances of Fe-Cr-C surfacing layers with different chemical compositions were compared using MLGS-225 C dry and wet rubber wheel abrasive wear tester. Moreover, the microstructures of the layers were observed by DM2700 M optical microscope and EM3-AX^(+)scanning electron microscope(SEM), the material compositions were analyzed by AZtecone XT energy disperse spectroscopy(EDS), and the hardness was tested by Wilson R574 Rockwell hardness tester. Results showed that the surfacing layer of 2# sample had the highest wear resistance, which was mainly attributed to the fact that the carbide content in 2# sample was the highest. Besides, the columnar and blocky primary carbides were evenly distributed in the layer and grew perpendicular to the substrate, which effectively protected the substrate and decreases the wear loss, and eventually improved the wear resistance of the surfacing layer.