（Ti, Nb）C reinforced Fe based laser coatings were prepared with normal and high scanning velocities of the laser beam. The distribution characteristics of reinforced particles in the coatings were investigated. The ...（Ti, Nb）C reinforced Fe based laser coatings were prepared with normal and high scanning velocities of the laser beam. The distribution characteristics of reinforced particles in the coatings were investigated. The mechanical properties of coatings were tested. The results showed that the morphologies of the microstructure and the reinforced particle changed dramatically at high solidification rate due to rapid laser processing compared with that prepared by normal processing. Two kinds of particles were observed in the coating. One was （Ti, Nb）C multiple carbide particle with the size of micron and sub micron scales, in which a mass of dislocations were found. Another was nano sized particle including a Fe and （Ti, Nb）C obtained by rapid solidification. The microstructure of the coatings was highly refined and a large number of twin crystals were found in matrix. The resuhs of mechanical properties test revealed that the wear resistance of the coaling was improved by rapid laser processing, compared with that of the coating prepared with normal speeds. The ahove-mentioned conclusion indicated that rapid laser cladding can promote not on ly the processing efficiency but also lhe mechanical properties of the coating.展开更多
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
基金Item Sponsored by National Natural Science Foundation of China(51275006,51274016)Natural Science Foundation of Beijing of China(2142009)Scientific Plan Item of Beijing Education Committee of China(PXM2015-014204-500170)
文摘（Ti, Nb）C reinforced Fe based laser coatings were prepared with normal and high scanning velocities of the laser beam. The distribution characteristics of reinforced particles in the coatings were investigated. The mechanical properties of coatings were tested. The results showed that the morphologies of the microstructure and the reinforced particle changed dramatically at high solidification rate due to rapid laser processing compared with that prepared by normal processing. Two kinds of particles were observed in the coating. One was （Ti, Nb）C multiple carbide particle with the size of micron and sub micron scales, in which a mass of dislocations were found. Another was nano sized particle including a Fe and （Ti, Nb）C obtained by rapid solidification. The microstructure of the coatings was highly refined and a large number of twin crystals were found in matrix. The resuhs of mechanical properties test revealed that the wear resistance of the coaling was improved by rapid laser processing, compared with that of the coating prepared with normal speeds. The ahove-mentioned conclusion indicated that rapid laser cladding can promote not on ly the processing efficiency but also lhe mechanical properties of the coating.
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.
