渗硼对球墨铸铁组织和耐磨性能的影响

Influence of boronizing on microstructure and wear resistance of ductile iron

为了提高球墨铸铁件的使用性能和使用寿命,对球墨铸铁进行了固体渗硼处理实验。利用金相显微镜、扫描电子显微镜和X射线衍射仪分析了渗硼层的厚度和渗硼层的组织,并测定了渗硼层的显微硬度,研究了渗硼对球墨铸铁耐磨性的影响。结果表明:球墨铸铁经渗硼处理后,其渗硼层由Fe2B单相组成,渗硼层呈齿状嵌入基体中。渗硼层的厚度随时间延长而增加。球墨铸铁经渗硼处理可获得较高的表面硬度,可达6.49 GPa。渗硼处理能明显改善球墨铸铁的耐磨性,是球墨铸铁的相对耐磨性的2.45倍。

This paper is concerned with solid powder boronizing treatment of the ductile iron in order to improve the performance and service life of ductile iron parts.The paper introduces the analysis of the microstructure and thickness of the boriding layers using Microscope（OM）,SEM and XRD,the determination of microhardness of specimen cross section by boriding layers,and investigation into effect of boronizing on wear resistance of ductile iron.The results show that the ductile iron,subjected to boronizing treatment,exhibits boriding layers consisting of single-phases of Fe2B,and embedding in the substrate as indention shape.Thickness of boriding layers increases with boronixing treating duration.The ductile iron after boronizing treatment shows better surface microhardness up to 6.49 GPa.Boronizing treatment gives an obvious increase in wear resistance of ductile iron.The boriding layers give relative wear resistance 2.45 times relative wear resistance of ductile iron.