Laser cladding nickel-based alloy coating （Ni60） and nickel-based composite coating doped with WC particles by 35 % （WCp/Ni） were produced on the low-carbon steel substrate by CO2 continuous wave laser with power ...Laser cladding nickel-based alloy coating （Ni60） and nickel-based composite coating doped with WC particles by 35 % （WCp/Ni） were produced on the low-carbon steel substrate by CO2 continuous wave laser with power of 5 kW using the injected powder technique. The effect of laser power on microstructure and wear resistance of laser cladding WCp/Ni cermet coating was investigated. The WCp/Ni alloy coating with evenly distributed WC ceramic phases and the better bond with the substrate alloy was obtained at a power of 2.2 kW. Diffusion solution reaction happened between WC particles and the substrate alloy during laser cladding, and led to the formation of block rich-tungsten carbide on the edges of the WC particles, especially at higher power. The WCp/Ni alloy coating consists of the undissolved WC particles, the block or dendritic rich-tungsten carbide, the bar-like rich-chromium carbide, and dendrite solid solution and eutectic structure among the carbides. Microhardness and wear resistance of the WCp/Ni coating at different powers were much higher or better than those of Ni60 alloy coating, and the best results were obtained at power of 2.2 kW.展开更多
The coarse WC particles ceramic-metal com- posite coatings with WC density of 67 wt-% and thickness of 1.0-1.2 mm have been cladded on 20Ni4Mo steel surface by a 2 kW CO_2 laser.The sintered WC particles with the size...The coarse WC particles ceramic-metal com- posite coatings with WC density of 67 wt-% and thickness of 1.0-1.2 mm have been cladded on 20Ni4Mo steel surface by a 2 kW CO_2 laser.The sintered WC particles with the size of 600-1000 μm are chosen as the main strengthening phase, Ni-base self-flux alloy as the binder in the compo- site coatings.The microstructure and microhardness of both WC particles and binder are analysed.The rigid ball indention with acoustic emission technique is used to evaluate the brittleness of the coating.Finally,the abrasive wear resistance of the coating is tested.Besides,the coatings with the same ratio and size of WC parti- cles in low carbon steel tube rod were cladded on 20Ni4Mo steel by atomic hydrogen welding tech- nique and analysed by the same way,their results are compared.展开更多
High-entropy alloy(HEA)coatings are of great importance in the fabrication of wear resistance materials.HEA coatings containing ceramic particles as reinforcement phase usually have better wear performance.In this stu...High-entropy alloy(HEA)coatings are of great importance in the fabrication of wear resistance materials.HEA coatings containing ceramic particles as reinforcement phase usually have better wear performance.In this study,AlCoCrFe Ni(TiN)_(x)(x:molar ratio;x=0,0.2,0.4,0.6,0.8,1.0)HEA coatings were fabricated on Q235 steel by plasma spray first and then subjected to laser remelting.The experimental results confirm that plasma spray together with post laser remelting could result in the in-situ formation of TiN-Al_(2)O_(3) ceramic particles and cuboidal B2 phase in the AlCoCrFeNi(TiN)_(x) HEA coatings.The in-situ TiN-Al_(2)O_(3) and nano-cuboidal B2 precipitation phase strengthened the coatings and improved their wearresistance properties.Due to the dispersion of hard phase and nano-particles resulting from second heating,the microhardness of the Al Co Cr Fe Ni(Ti N)coatings significantly increased from 493 to 851 HV after laser remelting.For the same reasons,the wear-resistance performance was also significantly promoted after laser remelting.展开更多
基金Item Sponsored by Research Programof Anhui Science and Technology Office (2005KJ030) and Korea Research FoundationGrant (KRF-2004-005-D00096)
文摘Laser cladding nickel-based alloy coating （Ni60） and nickel-based composite coating doped with WC particles by 35 % （WCp/Ni） were produced on the low-carbon steel substrate by CO2 continuous wave laser with power of 5 kW using the injected powder technique. The effect of laser power on microstructure and wear resistance of laser cladding WCp/Ni cermet coating was investigated. The WCp/Ni alloy coating with evenly distributed WC ceramic phases and the better bond with the substrate alloy was obtained at a power of 2.2 kW. Diffusion solution reaction happened between WC particles and the substrate alloy during laser cladding, and led to the formation of block rich-tungsten carbide on the edges of the WC particles, especially at higher power. The WCp/Ni alloy coating consists of the undissolved WC particles, the block or dendritic rich-tungsten carbide, the bar-like rich-chromium carbide, and dendrite solid solution and eutectic structure among the carbides. Microhardness and wear resistance of the WCp/Ni coating at different powers were much higher or better than those of Ni60 alloy coating, and the best results were obtained at power of 2.2 kW.
文摘The coarse WC particles ceramic-metal com- posite coatings with WC density of 67 wt-% and thickness of 1.0-1.2 mm have been cladded on 20Ni4Mo steel surface by a 2 kW CO_2 laser.The sintered WC particles with the size of 600-1000 μm are chosen as the main strengthening phase, Ni-base self-flux alloy as the binder in the compo- site coatings.The microstructure and microhardness of both WC particles and binder are analysed.The rigid ball indention with acoustic emission technique is used to evaluate the brittleness of the coating.Finally,the abrasive wear resistance of the coating is tested.Besides,the coatings with the same ratio and size of WC parti- cles in low carbon steel tube rod were cladded on 20Ni4Mo steel by atomic hydrogen welding tech- nique and analysed by the same way,their results are compared.
基金Natural Science Foundation of Liaoning Province(No.2019-MS-247)Liao Ning Revitalization Talents Program(No.XLYC1807178)+1 种基金Research Fund of the State Key Laboratory of Solidification Processing(No.SKLSP202011)International Cooperation Project of Guangdong Province(No.2021A0505030052)。
文摘High-entropy alloy(HEA)coatings are of great importance in the fabrication of wear resistance materials.HEA coatings containing ceramic particles as reinforcement phase usually have better wear performance.In this study,AlCoCrFe Ni(TiN)_(x)(x:molar ratio;x=0,0.2,0.4,0.6,0.8,1.0)HEA coatings were fabricated on Q235 steel by plasma spray first and then subjected to laser remelting.The experimental results confirm that plasma spray together with post laser remelting could result in the in-situ formation of TiN-Al_(2)O_(3) ceramic particles and cuboidal B2 phase in the AlCoCrFeNi(TiN)_(x) HEA coatings.The in-situ TiN-Al_(2)O_(3) and nano-cuboidal B2 precipitation phase strengthened the coatings and improved their wearresistance properties.Due to the dispersion of hard phase and nano-particles resulting from second heating,the microhardness of the Al Co Cr Fe Ni(Ti N)coatings significantly increased from 493 to 851 HV after laser remelting.For the same reasons,the wear-resistance performance was also significantly promoted after laser remelting.
