摘要
目的提高65Mn钢的固体粉末渗铬层厚度和耐磨性能。方法对65Mn钢进行超声冲击(UI)和固体粉末渗铬(SPC)相结合的复合工艺处理。采用X射线衍射仪(XRD)、光学显微镜(OM)、扫描电镜(SEM)和能谱仪(EDS),研究UI+SPC复合工艺处理后65Mn渗铬层的物相结构、厚度及元素分布。通过显微维氏硬度计、摩擦磨损试验机研究渗铬层的显微硬度和摩擦磨损性能。结果SPC处理试样的渗层厚度约为45μm,UI+SPC复合工艺处理试样的渗层厚度约为58μm,相比SPC试样,渗层厚度提高了13μm。渗铬层表面均匀致密,主要相组成为(Cr,Fe)_(23)C_(6)、(Cr,Fe)_(7)C_(6)、Cr_(2)C。UI+SPC试样渗层表面硬度达1659HV,约为基体表面硬度的6倍,且硬度从表面至心部呈梯度下降。UI+SPC试样表面渗铬层具有较好的耐磨性能,平均摩擦系数为0.170,磨损量约为基材的1/4,其主要磨损机理为粘着磨损和氧化磨损,伴随着磨粒磨损。结论UI可有效提高SPC工艺的Cr原子扩散性能,提高渗铬层厚度。相比于单一的SPC处理试样,UI+SPC复合工艺处理试样渗铬层的耐磨性显著提高。UI处理的加入,使SPC试样的磨损机理由“磨粒+粘着”转化为“粘着、氧化+磨粒”。
This paper aims to improve the solid powder chromized layer thickness and wear resistance of 65Mn steel.The composite process of ultrasonic impact(UI)and solid powder chromizing(SPC)is carried out on 65Mn steel.The phase structure,thickness,and element distribution of the 65Mn chromized layer after UI+SPC treatments are studied by X-ray diffractometer(XRD),optical microscope(OM),scanning electron microscope(SEM)and energy dispersive spectrometer(EDS).The microhardness and friction-wear properties of the chromized layer after UI+SPC treatments are investigated by the microhardness tester and friction-wear tester.The results demonstrate that the thickness of the chromizing layer is 45μm by the UI treatment and the thickness is 58μm by the UI+SPC treatment,13μm thicker than the former.The surface structure of chromized layer is uniform and compact,and the main phase composition is(Cr,Fe)_(23)C_(6),(Cr,Fe)_(7)C_(6) and Cr_(2)C.The surface hardness of the chromized layer reaches 1659HV by UI+SPC treatment,which is about six times of the surface hardness of the substrate,and the hardness distribution of the chromized layer show gradient descent from the surface to the inside.The surface chromized layer of the 65Mn steel has good anti-wear properties after UI+SPC treatment.The average friction coefficient is 0.170,and its wear weightlessness is about one-fourth of the that of the substrate.The dominating wear mechanism of UI+SPC sample is adhesive wear and oxidation wear,associated with slight abrasive wear.UI can effectively enhance the Cr atom diffusion property of SPC process and improve the thickness of chromized layer.Compared with SPC treatment,the wear resistance of the sample is significantly improved by UI+SPC treatment.With the addition of UI treatment,the wear mechanism of SPC samples changes from“abrasive+adhesive”to“adhesive,oxidation+abrasive”.
作者
王志明
李庆达
汪昊
王宏立
胡军
赵胜雪
WANG Zhi-ming;LI Qing-da;WANG Hao;WANG Hong-li;HU Jun;ZHAO Sheng-xue(College of Engineering,Heilongjiang Bayi Agricultural University,Daqing 163319,China)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2022年第1期52-59,85,共9页
Surface Technology
基金
黑龙江省自然科学优秀青年基金(YQ2019E032)
国家重点研发计划子课题(2017YFC1601905—04)。
关键词
超声冲击
固体粉末渗铬
渗铬层
磨粒磨损
氧化磨损
粘着磨损
ultrasonic impact
solid power chromizing
chromized layer
abrasive wear
oxidative wear
adhesive wear
