A nickel-based coating was deposited on the pure Al substrate by immersion plating,and the Al/Cu bimetals were prepared by diffusion bonding in the temperature range of 450-550 ℃.The interce microstructure and fractu...A nickel-based coating was deposited on the pure Al substrate by immersion plating,and the Al/Cu bimetals were prepared by diffusion bonding in the temperature range of 450-550 ℃.The interce microstructure and fracture surface of Al/Cu joints were studied by scanning electron microscopy(SEM) and X-ray diffraction(XRD).The mechanical properties of the Al/Cu bimetals were measured by tensile shear and microhardness tests.The results show that the Ni interiayer can effectively eliminate the formation of Al-Cu intermetallic compounds.The Al/Ni interface consists of the Al3Ni and Al3Ni2 phases,while it is Ni-Cu solid solution at the Ni/Cu interce.The tensile shear strength of the joints is improved by the addition of Ni interiayer.The joint with Ni interiayer annealed at 500 ℃ exhibits a maximum value of tensile shear strength of 34.7 MPa.展开更多
In order to improve corrosion resistance of stainless steel 316L in warm acidic solution, Ni?Cu?P coatings with high copper and phosphorus contents were deposited onto stainless steel 316L substrates via electroless...In order to improve corrosion resistance of stainless steel 316L in warm acidic solution, Ni?Cu?P coatings with high copper and phosphorus contents were deposited onto stainless steel 316L substrates via electroless plating. The structure of the film and its resistance to corrosion in a warm acidic environment were investigated using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction spectrometry (XRD), polarization curves, electrochemical impedance spectroscopy (EIS), and dipping corrosion tests, respectively. The results demonstrate that Ni?Cu?P coatings consist of two types of nodules, which are 19.98% Cu and 39.17% Cu (mass fraction) respectively. The corrosion resistance of the 316L substrate when subjected to a warm acidic solution is significantly improved by the addition of the new type of the Ni?Cu?P coating. The as-plated coatings demonstrate better corrosion resistance than annealed coatings. As-plated coatings and those annealed at 673 K are found to corrode selectively, while pitting is observed to be the main corrosion mechanism of coatings annealed at 773 and 873 K.展开更多
The wetting of molten Sn-3.5Ag-0.5Cu alloy on the Ni-P(-SiC)coated SiCp/Al substrates was investigated by electroless Ni plating process,and the microstructures of the coating and the interfacial behavior of wetting s...The wetting of molten Sn-3.5Ag-0.5Cu alloy on the Ni-P(-SiC)coated SiCp/Al substrates was investigated by electroless Ni plating process,and the microstructures of the coating and the interfacial behavior of wetting systems were analyzed.The SiC particles are evenly distributed in the coating and enveloped with Ni.No reaction layer is observed at the coating/SiCp/Al composite interfaces.The contact angle increases from^19°with the Ni-P coating to 29°,43°and 113°with the corresponding Ni-P-3SiC,Ni-P-6SiC and Ni-P-9SiC coatings,respectively.An interaction layer containing Cu,Ni,Sn and P forms at the Sn-Ag-Cu/Ni-P-(0,3,6)SiC coated SiCp/Al interfaces,and the Cu-Ni-Sn and Ni-Sn-P phases are detected in the interaction layer.Moreover,the molten Sn-Ag-Cu can penetrate into the Ni-P(-SiC)coatings through the Ni-P/SiC interface and dissolve them to contact the SiCp/Al substrate.展开更多
The effects of additives(polyethylene glycol(PEG),sodium dodecyl sulfate(SDS))and WC nano-powder on the microstructure,relative density,hardness and electrical conductivity of electroplated WC−Cu composite were invest...The effects of additives(polyethylene glycol(PEG),sodium dodecyl sulfate(SDS))and WC nano-powder on the microstructure,relative density,hardness and electrical conductivity of electroplated WC−Cu composite were investigated.The preparation mechanism was also studied.The microstructure of samples was analyzed by XRD,SEM,EDS,TEM and HRTEM.The synergistic effect of PEG and SDS made the WC−Cu composite more compact during the electroplating process.The hardness of WC−Cu composites increased with the increase in WC content,while the electrical conductivity decreased with the increase in WC content.The density of samples tended to increase initially and then decreased with increase in the additive content.When the electroplating solution contained 10 g/L WC nanopowder,0.2 g/L PEG and 0.1 g/L SDS,the WC−Cu composite exhibited hardness of HV 221 and electric conductivity of 53.7 MS/m.Therefore,the results suggest that WC−Cu composite with excellent properties can be obtained by optimizing the content of additives and WC particles.展开更多
Pd-Co films with the Co content varying from 21.9% to 34.62%(mole fraction) and Pd-Cu(5% Cu, mole fraction) film were electrodeposited on 316 L stainless steel, and the erosion-corrosion resistance of the Pd-Co an...Pd-Co films with the Co content varying from 21.9% to 34.62%(mole fraction) and Pd-Cu(5% Cu, mole fraction) film were electrodeposited on 316 L stainless steel, and the erosion-corrosion resistance of the Pd-Co and Pd-Cu plated samples in a simulated boiling pure terephthalic acid(PTA) slurry environment was studied with methods of mass loss test, polarization measurement and scanning electron microscopy(SEM). Under the static state condition, both the Pd-Cu and Pd-Co plated samples exhibit good corrosion resistance and the Pd-Cu film behaves slightly better. However, with increasing the stirring speed, the corrosion rate of the Pd-Cu plated samples increases obviously while that of the Pd-Co plated samples shows only slight increase. Higher microhardness and lower surface roughness of Pd-Co film than those of Pd-Cu film, as well as good corrosion resistance, may be the main reasons for better erosion-corrosion resistance in the strong reductive acid plus erosion environment.展开更多
以镀Ni-Cu-La-B玻璃纤维与镍粉为复合填料,以丙烯酸树脂作为粘结剂,研制了一种新型电磁波屏蔽复合材料—镀Ni-Cu-La-B玻璃纤维/镍粉/丙烯酸树脂,在300 k Hz^1.5 GHz频率范围内,其电磁屏蔽性能达到47.777~64.284 d B。最后,介绍了这种新...以镀Ni-Cu-La-B玻璃纤维与镍粉为复合填料,以丙烯酸树脂作为粘结剂,研制了一种新型电磁波屏蔽复合材料—镀Ni-Cu-La-B玻璃纤维/镍粉/丙烯酸树脂,在300 k Hz^1.5 GHz频率范围内,其电磁屏蔽性能达到47.777~64.284 d B。最后,介绍了这种新型电磁波屏蔽复合材料的物理性能指标、主要特点及发展前景。展开更多
文摘采用多层电镀技术在锌合金基体上镀Ni-Cu-Ni镀层,研究阳极活化剂、电流密度、镀液温度、p H值及搅拌方式等对Ni-Cu-Ni镀层特性的影响,以无氰镀铜替代有氰镀铜Ni-Cu-Ni多层电镀工艺,通过增加中间Cu层厚度降低整体镀层中贵重金属Ni的用量以实现降低成本、无毒环保的绿色新工艺.研究表明,普通Ni作为打底层,镀酸Cu为中间层,镀光亮Ni作表层,利用镀层电位差及镀层错位效应可有效减少贵重金属Ni的用量,并在保持镀层美观的同时满足防腐等表面处理要求;Ni-Cu-Ni镀层结合力良好,150℃热震及锉刀划痕试验镀层无脱落起皮,镀件耐NSS可达48 h,耐5.0%Na Cl浸泡可达100 h.
基金Projects (51274054,51375070,51271042) supported by the National Natural Science Foundation of ChinaProjects (2013M530913) supported by the China Postdoctoral Science Foundation
文摘A nickel-based coating was deposited on the pure Al substrate by immersion plating,and the Al/Cu bimetals were prepared by diffusion bonding in the temperature range of 450-550 ℃.The interce microstructure and fracture surface of Al/Cu joints were studied by scanning electron microscopy(SEM) and X-ray diffraction(XRD).The mechanical properties of the Al/Cu bimetals were measured by tensile shear and microhardness tests.The results show that the Ni interiayer can effectively eliminate the formation of Al-Cu intermetallic compounds.The Al/Ni interface consists of the Al3Ni and Al3Ni2 phases,while it is Ni-Cu solid solution at the Ni/Cu interce.The tensile shear strength of the joints is improved by the addition of Ni interiayer.The joint with Ni interiayer annealed at 500 ℃ exhibits a maximum value of tensile shear strength of 34.7 MPa.
基金Project(CKJA201202)supported by the Innovation Fund Key Project of Nanjing Institute of Technology,ChinaProject(51301088)supported by the National Natural Science Foundation of China
文摘In order to improve corrosion resistance of stainless steel 316L in warm acidic solution, Ni?Cu?P coatings with high copper and phosphorus contents were deposited onto stainless steel 316L substrates via electroless plating. The structure of the film and its resistance to corrosion in a warm acidic environment were investigated using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction spectrometry (XRD), polarization curves, electrochemical impedance spectroscopy (EIS), and dipping corrosion tests, respectively. The results demonstrate that Ni?Cu?P coatings consist of two types of nodules, which are 19.98% Cu and 39.17% Cu (mass fraction) respectively. The corrosion resistance of the 316L substrate when subjected to a warm acidic solution is significantly improved by the addition of the new type of the Ni?Cu?P coating. The as-plated coatings demonstrate better corrosion resistance than annealed coatings. As-plated coatings and those annealed at 673 K are found to corrode selectively, while pitting is observed to be the main corrosion mechanism of coatings annealed at 773 and 873 K.
基金Projects(51572112,51401034)supported by the National Natural Science Foundation of ChinaProject(BK20151340)supported by the Natural Science Foundation of Jiangsu Province,China+3 种基金Projects(2014-XCL-002,TD-XCL-004)supported by the Six Talent Peaks Project of Jiangsu Province,ChinaProject(BRA2017387)supported by the 333 Talents Project of Jiangsu Province,ChinaProject([2015]26)supported by the Innovation/Entrepreneurship Program of Jiangsu Province,ChinaProject([2016]15)supported by the Qing Lan Project,China
文摘The wetting of molten Sn-3.5Ag-0.5Cu alloy on the Ni-P(-SiC)coated SiCp/Al substrates was investigated by electroless Ni plating process,and the microstructures of the coating and the interfacial behavior of wetting systems were analyzed.The SiC particles are evenly distributed in the coating and enveloped with Ni.No reaction layer is observed at the coating/SiCp/Al composite interfaces.The contact angle increases from^19°with the Ni-P coating to 29°,43°and 113°with the corresponding Ni-P-3SiC,Ni-P-6SiC and Ni-P-9SiC coatings,respectively.An interaction layer containing Cu,Ni,Sn and P forms at the Sn-Ag-Cu/Ni-P-(0,3,6)SiC coated SiCp/Al interfaces,and the Cu-Ni-Sn and Ni-Sn-P phases are detected in the interaction layer.Moreover,the molten Sn-Ag-Cu can penetrate into the Ni-P(-SiC)coatings through the Ni-P/SiC interface and dissolve them to contact the SiCp/Al substrate.
文摘The effects of additives(polyethylene glycol(PEG),sodium dodecyl sulfate(SDS))and WC nano-powder on the microstructure,relative density,hardness and electrical conductivity of electroplated WC−Cu composite were investigated.The preparation mechanism was also studied.The microstructure of samples was analyzed by XRD,SEM,EDS,TEM and HRTEM.The synergistic effect of PEG and SDS made the WC−Cu composite more compact during the electroplating process.The hardness of WC−Cu composites increased with the increase in WC content,while the electrical conductivity decreased with the increase in WC content.The density of samples tended to increase initially and then decreased with increase in the additive content.When the electroplating solution contained 10 g/L WC nanopowder,0.2 g/L PEG and 0.1 g/L SDS,the WC−Cu composite exhibited hardness of HV 221 and electric conductivity of 53.7 MS/m.Therefore,the results suggest that WC−Cu composite with excellent properties can be obtained by optimizing the content of additives and WC particles.
基金Project(2012BAE04B01) supported by the National Key Technology Research and Development Program of the Ministry of Science and Technology of China
文摘Pd-Co films with the Co content varying from 21.9% to 34.62%(mole fraction) and Pd-Cu(5% Cu, mole fraction) film were electrodeposited on 316 L stainless steel, and the erosion-corrosion resistance of the Pd-Co and Pd-Cu plated samples in a simulated boiling pure terephthalic acid(PTA) slurry environment was studied with methods of mass loss test, polarization measurement and scanning electron microscopy(SEM). Under the static state condition, both the Pd-Cu and Pd-Co plated samples exhibit good corrosion resistance and the Pd-Cu film behaves slightly better. However, with increasing the stirring speed, the corrosion rate of the Pd-Cu plated samples increases obviously while that of the Pd-Co plated samples shows only slight increase. Higher microhardness and lower surface roughness of Pd-Co film than those of Pd-Cu film, as well as good corrosion resistance, may be the main reasons for better erosion-corrosion resistance in the strong reductive acid plus erosion environment.
文摘以镀Ni-Cu-La-B玻璃纤维与镍粉为复合填料,以丙烯酸树脂作为粘结剂,研制了一种新型电磁波屏蔽复合材料—镀Ni-Cu-La-B玻璃纤维/镍粉/丙烯酸树脂,在300 k Hz^1.5 GHz频率范围内,其电磁屏蔽性能达到47.777~64.284 d B。最后,介绍了这种新型电磁波屏蔽复合材料的物理性能指标、主要特点及发展前景。