A novel Ni-P-SiC composite coating was prepared by electroless plating in order to improve the corrosion capacity and wear resistance of AZ91D magnesium alloy.The influence of pH values on deposition rates and propert...A novel Ni-P-SiC composite coating was prepared by electroless plating in order to improve the corrosion capacity and wear resistance of AZ91D magnesium alloy.The influence of pH values on deposition rates and properties of the coatings was studied.The microstructure and phase structure of the Ni-P-SiC coatings were analyzed by scanning electron microscopy(SEM)and X-ray diffractometry(XRD).The corrosion and wear resistance performances of the coatings were also investigated through electrochemical technique and pin-on-disk tribometer,respectively.The results indicate that the composite coating is composed of Ni, P and SiC.It exhibits an amorphous structure and good adhesion to the substrate.The coatings have higher open circuit potential than that of the substrate.The composite coating obtained at pH value of 5.2 possesses optimal integrated properties,which shows similar corrosion resistance and ascendant wear resistance properties to the substrate.展开更多
Ni-P(-SiC)composite coatings were successfully deposited on 70 vol%SiC_(p)/Al composite by electroless plating.The surface microstructures and the phase structures of the Ni-P(-SiC)coatings were examined and analyzed ...Ni-P(-SiC)composite coatings were successfully deposited on 70 vol%SiC_(p)/Al composite by electroless plating.The surface microstructures and the phase structures of the Ni-P(-SiC)coatings were examined and analyzed by scanning electron microscopy(SEM)and X-ray diffraction(XRD)before and after heat-treatment at200-400℃for 2 h.The thermal diffusivity of the deposited samples and the interface adhesion between the coating and the substrate were investigated.The experimental results show that SiC content in the coatings increases obviously and XRD peaks are enhanced with SiC content in the bath increasing from 3 to 9 g·L^(-1).After heat-treatment,the surface of the coating becomes smoother and no diffusion layer is produced at the interface.A new phase Ni3P forms in the coating during heat-treatment at 400℃.The critical load(L_(c))of Ni-P-SiC composite coating on SiC_(p)/Al composite reaches the maximum value of 84.9 N with SiC content of 3 g·L^(-1)after heat-treatment at 200℃and more or less decreases with the increase in SiC content and heat-treatment temperature.The thermal diffusivity of deposited samples gradually increases as the temperature increases;however,it reduces firstly and then climbs with the increase in SiC content.展开更多
Ni-P-SiC composite coatings were electroplated on carbon steel substrate assisted by mechanical attrition (MA). The MA action was conducted by dispersing glass balls on the cathodic surface, vibrating in the horizon...Ni-P-SiC composite coatings were electroplated on carbon steel substrate assisted by mechanical attrition (MA). The MA action was conducted by dispersing glass balls on the cathodic surface, vibrating in the horizontal direction. The experimental results show that, under the assistant of MA action, the adhesion of Ni-P-SiC coating on the steel substrate can be improved effectively, and the Ni-P-SiC coatings exhibit a crystallized structure and Ni-P matrix can combine tightly with SiC particles, and the hardness and corrosion resistance of these coatings increase markedly. During heat treatment, the defects produced in conventional Ni-P-SiC composite coatings can be avoided assisted by MA action. Both of the wear of these coatings can be improved further.展开更多
基金Project(KJ070602)supported by Program of Applied Science Foundation of Chongqing Education Committee,ChinaProject(KF0604)supported by the Open Foundation of Key Laboratory of Low Dimensional Materials&Application Technology(Xiangtan University),Ministry of Education,China
文摘A novel Ni-P-SiC composite coating was prepared by electroless plating in order to improve the corrosion capacity and wear resistance of AZ91D magnesium alloy.The influence of pH values on deposition rates and properties of the coatings was studied.The microstructure and phase structure of the Ni-P-SiC coatings were analyzed by scanning electron microscopy(SEM)and X-ray diffractometry(XRD).The corrosion and wear resistance performances of the coatings were also investigated through electrochemical technique and pin-on-disk tribometer,respectively.The results indicate that the composite coating is composed of Ni, P and SiC.It exhibits an amorphous structure and good adhesion to the substrate.The coatings have higher open circuit potential than that of the substrate.The composite coating obtained at pH value of 5.2 possesses optimal integrated properties,which shows similar corrosion resistance and ascendant wear resistance properties to the substrate.
基金financially supported by the National Natural Science Foundation of China(Nos.51572112,51172177)the Natural Science Foundation of Jiangsu Province(Nos.BK20151340)+2 种基金the Six Talent Peaks Project of Jiangsu Province(No.2014-XCL-002)the Postdoctoral Science Foundation of China(No.2014M551512)the Innovation/Entrepreneurship Program of Jiangsu Province(Nos.[2013]477,[2015]26)。
文摘Ni-P(-SiC)composite coatings were successfully deposited on 70 vol%SiC_(p)/Al composite by electroless plating.The surface microstructures and the phase structures of the Ni-P(-SiC)coatings were examined and analyzed by scanning electron microscopy(SEM)and X-ray diffraction(XRD)before and after heat-treatment at200-400℃for 2 h.The thermal diffusivity of the deposited samples and the interface adhesion between the coating and the substrate were investigated.The experimental results show that SiC content in the coatings increases obviously and XRD peaks are enhanced with SiC content in the bath increasing from 3 to 9 g·L^(-1).After heat-treatment,the surface of the coating becomes smoother and no diffusion layer is produced at the interface.A new phase Ni3P forms in the coating during heat-treatment at 400℃.The critical load(L_(c))of Ni-P-SiC composite coating on SiC_(p)/Al composite reaches the maximum value of 84.9 N with SiC content of 3 g·L^(-1)after heat-treatment at 200℃and more or less decreases with the increase in SiC content and heat-treatment temperature.The thermal diffusivity of deposited samples gradually increases as the temperature increases;however,it reduces firstly and then climbs with the increase in SiC content.
基金supported by the National Natural Science Foundation of China (No.50671006)
文摘Ni-P-SiC composite coatings were electroplated on carbon steel substrate assisted by mechanical attrition (MA). The MA action was conducted by dispersing glass balls on the cathodic surface, vibrating in the horizontal direction. The experimental results show that, under the assistant of MA action, the adhesion of Ni-P-SiC coating on the steel substrate can be improved effectively, and the Ni-P-SiC coatings exhibit a crystallized structure and Ni-P matrix can combine tightly with SiC particles, and the hardness and corrosion resistance of these coatings increase markedly. During heat treatment, the defects produced in conventional Ni-P-SiC composite coatings can be avoided assisted by MA action. Both of the wear of these coatings can be improved further.