GCr15钢激光B_(4)C/Cr合金化层的组织及耐蚀性能  

Microstructure and Corrosion Resistance of Laser B_(4)C/Cr Alloyed Layer of GCr15 Steel

作　　者：童冰倩 李振兴 张群莉 姚喆赫[1,2,3] 陈智君 姚建华 Tong Bingqian;Li Zhenxing;Zhang Qunli;Yao Zhehe;Chen Zhijun;Yao Jianhua(Institute of Laser Advanced Manufacturing,Zhejiang University of Technology,Hangzhou,Zhejiang 310023,China;Zhejiang Provincial Collaboration Innovation Center of High-End Laser Manufacturing Equipment,Hangzhou,Zhejiang 310023,China;College of Mechanical Engineering,Zhejiang University of Technology,Hangzhou,Zhejiang 310023,China;Hangzhou Bohua Laser Technology Co.,Ltd.,Hangzhou,Zhejiang 311199,China)

机构地区：[1]浙江工业大学激光先进制造研究院,浙江杭州310023 [2]浙江省高端激光制造装备协同创新中心,浙江杭州310023 [3]浙江工业大学机械工程学院,浙江杭州310023 [4]杭州博华激光技术有限公司,浙江杭州311199

出　　处：《中国激光》2021年第10期187-195,共9页Chinese Journal of Lasers

基　　金：国家重点研发计划(2018YFB0407300);国家自然科学基金(51705460);浙江省省属高校基本科研业务费项目(科技类)(RF-C2019003)。

摘　　要：采用激光合金化技术在GCr15钢表面制备了耐腐蚀的Cr合金化层,用扫描电子显微镜、能谱仪和X射线衍射仪分析了合金化层的显微组织和物相,并测试了合金化层的硬度和电化学腐蚀性能。实验结果表明,合金化层与基材呈良好的冶金结合,显微组织为典型的枝晶组织。相比纯Cr粉获得的合金化层,B_(4)C/Cr混合粉末获得的合金化层组织更精细,且存在Fe_(2)B和CrB两种新的强化相。B_(4)C的添加在一定程度上提高了合金化层的硬度和耐蚀性。当B_(4)C与Cr两种粉末的质量比为1∶16时,合金化层的显微硬度约为621 HV,是基体的2~3倍,且腐蚀电位较高,耐腐蚀性好。Objective GCr15 steel is a high-carbon steel with high hardness and good wear resistance.It has been widely used in many fields,such as the automotive industry,aviation equipment,transport ships.However,the corrosion resistance of GCr15 steel is poor,and its components suffer early fatigue failure due to corrosion.It can be characterized by the phenomenon that when it is used in marine equipment,its service life is short due to the erosion effect of Cl^(-).The corrosion resistance of GCr15 steel can be improved by adjusting its microstructure.However,simultaneously,the corrosion resistance is closely related to the composition.There are some limitations in improving the corrosion resistance by simply adjusting the microstructure.Laser surface alloying(LSA)is a typical surface strengthening technology,which is often used to adjust the distribution of elements and microstructure nearing the metal surface,so it has a broad application prospect in improving the mechanical properties and corrosion resistance of metal materials.Therefore,in this study,LSA is used to prepare Cr alloyed layer on the surface,and the effect of B_(4)C on the phase,hardness,and corrosion resistance of the alloyed layer is studied.Methods Using laser alloying,a corrosion-resistant high Cr alloyed layer is prepared on the surface of GCr15 steel.Before alloying,the substrate is preheated to avoid cracks.Then,the microstructure and phase of the alloyed layer are analyzed by optical microscope(OM),scanning electron microscope(SEM),energy dispersive spectrometer(EDS),and X-ray diffractometer(XRD).The electrochemical performance is tested by a conventional three-electrode system.The saturated calomel electrode is used as the reference electrode,the sample as the working electrode,and the platinum electrode as the auxiliary electrode.In this work,3.5% NaCl solution is used as the corrosive medium,the scanning speed is 1 mV/s,and the test time is 1800 s.The corrosion resistance is analyzed by polarization curve and impedance spectrum.Results and Disc

关 键 词：激光光学 GCR15钢 激光合金化 Cr合金化层 硬度 腐蚀性能 

分 类 号：TG178[金属学及工艺—金属表面处理] TG174.4[金属学及工艺—金属学]