To select the proper composition and obtain an overall material?microstructure?property relationship for Cu?Fe alloy, theeffect of Fe content on microstructure and properties of Cu?Fe-based composite coatings by laser...To select the proper composition and obtain an overall material?microstructure?property relationship for Cu?Fe alloy, theeffect of Fe content on microstructure and properties of Cu?Fe-based composite coatings by laser induction hybrid rapid claddingwas investigated. Microstructure characterization of the composite coatings was tested utilizing SEM, XRD and EDS. Microhardnessmeasurement was executed to evaluate the mechanical properties of the composite coatings. The results show that for low Fe content,the composite coating presents a feature that Fe-rich equiaxed dendrites are embedded in the Cu-rich matrix. With increasing Fecontent, the Fe-rich particles are dispersed in the Cu-rich matrix. With further increasing Fe content, large amounts of Cu-richparticles are homogeneously dispersed in the interdendrite of the Fe-rich matrix. Correspondingly, the average microhardness of thecomposite coatings increases gradually with the increase of Fe content and the microhardness of Cu14.5Fe83Si2C0.5 coating is muchtwice higher than that of the substrate.展开更多
The effect of overlapping treatment on microstructure of laser clad WC/Ni60A composite coating was studied with XRD, SEM, TEM and SAED etc. The results show that during the overlapping treatment the existence of the ...The effect of overlapping treatment on microstructure of laser clad WC/Ni60A composite coating was studied with XRD, SEM, TEM and SAED etc. The results show that during the overlapping treatment the existence of the residual heat and edge angle effect on the substrate has changed the composition and microstructure of the coating by raising the fusion temperature and increasing the dilution degree of the coating.展开更多
Ni60-WC particles are used to improve the wear resistance of hard-facing steel due to their high hardness. An emerging technology that combines laser with cold spraying to deposit the hard-facing coatings is known as ...Ni60-WC particles are used to improve the wear resistance of hard-facing steel due to their high hardness. An emerging technology that combines laser with cold spraying to deposit the hard-facing coatings is known as supersonic laser deposition. In this study, Ni60-WC is deposited on low-carbon steel using SLD. The microstructure and performance of the coatings are investigated through SEM, optical microscopy, EDS, XRD, microhardness and pin-on-disc wear tests. The experimental results of the coating processed with the optimal parameters are compared to those of the coating deposited using laser cladding.展开更多
通过6 k W横流CO2激光器在40Cr钢表面激光熔覆了不同成分配比的WC/Co50复合涂层。运用金相光学显微镜(OM),扫描电镜(SEM),能谱仪(EDS)和X射线衍射(XRD)等表征手段分析了涂层结合区形貌、显微组织和物相组成,测试了复合涂层的显微硬度和...通过6 k W横流CO2激光器在40Cr钢表面激光熔覆了不同成分配比的WC/Co50复合涂层。运用金相光学显微镜(OM),扫描电镜(SEM),能谱仪(EDS)和X射线衍射(XRD)等表征手段分析了涂层结合区形貌、显微组织和物相组成,测试了复合涂层的显微硬度和磨损性能。结果表明,外加的WC颗粒在高能激光束作用下大部分发生溶解,涂层主要由碳化物WC、W2C、(Cr,Fe)7C3和M6C及Fe-Cr固溶体等物相组成。涂层中组织结构比较复杂,出现了树枝状初晶、包状过共晶,枝晶间共晶和硬质相颗粒。WC/Co50熔覆涂层的最大显微硬度位于涂层次表面,其最大平均显微硬度为基材的1.93倍,且随着深度的增加逐渐降低。相同磨损条件下,复合涂层的磨损失重仅为基材的13.3%。展开更多
基金Projects(51471084,61475117)supported by the National Natural Science Foundation of ChinaProject(13ZCZDGX01109)supported by Tianjin Municipal Science and Technology Commission of ChinaProject(20122BBE500031)supported by the Key Technology Project of Jiangxi Province in China
文摘To select the proper composition and obtain an overall material?microstructure?property relationship for Cu?Fe alloy, theeffect of Fe content on microstructure and properties of Cu?Fe-based composite coatings by laser induction hybrid rapid claddingwas investigated. Microstructure characterization of the composite coatings was tested utilizing SEM, XRD and EDS. Microhardnessmeasurement was executed to evaluate the mechanical properties of the composite coatings. The results show that for low Fe content,the composite coating presents a feature that Fe-rich equiaxed dendrites are embedded in the Cu-rich matrix. With increasing Fecontent, the Fe-rich particles are dispersed in the Cu-rich matrix. With further increasing Fe content, large amounts of Cu-richparticles are homogeneously dispersed in the interdendrite of the Fe-rich matrix. Correspondingly, the average microhardness of thecomposite coatings increases gradually with the increase of Fe content and the microhardness of Cu14.5Fe83Si2C0.5 coating is muchtwice higher than that of the substrate.
文摘The effect of overlapping treatment on microstructure of laser clad WC/Ni60A composite coating was studied with XRD, SEM, TEM and SAED etc. The results show that during the overlapping treatment the existence of the residual heat and edge angle effect on the substrate has changed the composition and microstructure of the coating by raising the fusion temperature and increasing the dilution degree of the coating.
基金sponsored by the Centre for Industrial Photonics, Institute for Manufacture, Department of Engineering, University of Cambridgethe Natural Science Foundation of China (51271170)+1 种基金China International Science and Technology Cooperation Project (2011DFR50540)Major Scientific and Technological Special Key Industrial Project of Zhejiang Province (2012C11001)
文摘Ni60-WC particles are used to improve the wear resistance of hard-facing steel due to their high hardness. An emerging technology that combines laser with cold spraying to deposit the hard-facing coatings is known as supersonic laser deposition. In this study, Ni60-WC is deposited on low-carbon steel using SLD. The microstructure and performance of the coatings are investigated through SEM, optical microscopy, EDS, XRD, microhardness and pin-on-disc wear tests. The experimental results of the coating processed with the optimal parameters are compared to those of the coating deposited using laser cladding.
文摘通过6 k W横流CO2激光器在40Cr钢表面激光熔覆了不同成分配比的WC/Co50复合涂层。运用金相光学显微镜(OM),扫描电镜(SEM),能谱仪(EDS)和X射线衍射(XRD)等表征手段分析了涂层结合区形貌、显微组织和物相组成,测试了复合涂层的显微硬度和磨损性能。结果表明,外加的WC颗粒在高能激光束作用下大部分发生溶解,涂层主要由碳化物WC、W2C、(Cr,Fe)7C3和M6C及Fe-Cr固溶体等物相组成。涂层中组织结构比较复杂,出现了树枝状初晶、包状过共晶,枝晶间共晶和硬质相颗粒。WC/Co50熔覆涂层的最大显微硬度位于涂层次表面,其最大平均显微硬度为基材的1.93倍,且随着深度的增加逐渐降低。相同磨损条件下,复合涂层的磨损失重仅为基材的13.3%。
