Cathodic deposition current density of the composite coatings increases when SiC par-ticles and rare earth (RE) were added in the bath, which is profitable for Ni- W-P alloy to deposit in the cathod, forming Ni-W-P-Si...Cathodic deposition current density of the composite coatings increases when SiC par-ticles and rare earth (RE) were added in the bath, which is profitable for Ni- W-P alloy to deposit in the cathod, forming Ni-W-P-SiC and RE-Ni-W-P-SiC composite coatings. On the contrary, the addition of PTFE in the bath decreases cathodic deposition current density of the coatings. The current density increases a little when the amount of RE is 7-9g/l; however, the current density increases greatly when the amount of RE is increased to 11-13g/l. Bui ij the amount of RE is raised further, the current density decreases. Hardness and wear resistance of RE-Ni-W-P-SiC composite coating have been studied, and the results show that the hardness and wear resistance of RE-Ni-W-P-SiC composite coating increase with increasing heat treatment tempera-ture, which reach peak values at 400℃; while the hardness and wear resistance of the coating decrease with the rise of heat treated temperature continuously.展开更多
The formation of ceramic coatings on metal substrate by cathodic electrolytic deposition (CELD) has received more attention in recent years. But only thin filmscan be prepared via CELD. Yttrium stabilized zirconia (YS...The formation of ceramic coatings on metal substrate by cathodic electrolytic deposition (CELD) has received more attention in recent years. But only thin filmscan be prepared via CELD. Yttrium stabilized zirconia (YSZ) ceramic coatings were deposited on FeCrAI alloy by a novel technique--cathodic micro-arc electrodeposition (CMED).The result shows that, when a high pulse electric field is applied to the cathode which was pre-deposited with a thin YSZ film, dielectric breakdown occurs and micro-arc discharges appear. Coatings with reasonably thickness of-300μm and crystalline structure can be deposited on the cathode by utilizing the energy of the micro-arc. The thickness of the as-deposited coating is dominated by the voltage and the frequency. Y2O3 is co-deposited with ZrO2 when Y(NO3)3 was added to the electrolyte, which stabilize t-phase, t′-phase and c-phase of ZrO2 at room temperature. The amount of the m-ZrO2 in the coating is diminished by increasing the concentration of Y(NO3)3 in the electrolyte.This report describes the processing of CMED and studies the microstructure of the deposited YSZ coatings.展开更多
为了更深入地探讨Zn Fe SiO2复合镀层的电沉积机理,采用三电极体系下的动电位法测定了电沉积Zn Fe SiO2复合镀层的阴极极化曲线,并研究了镀液成分对阴极极化的影响。结果表明,Zn Fe SiO2复合镀层的沉积属于异常共沉积,而且SiO2微粒的... 为了更深入地探讨Zn Fe SiO2复合镀层的电沉积机理,采用三电极体系下的动电位法测定了电沉积Zn Fe SiO2复合镀层的阴极极化曲线,并研究了镀液成分对阴极极化的影响。结果表明,Zn Fe SiO2复合镀层的沉积属于异常共沉积,而且SiO2微粒的加入对Zn Fe SiO2镀层复合电沉积的阴极极化行为影响不大。展开更多
基金The project was supported by Yunnan Provincial Natural Science Foundation (95B11-5).
文摘Cathodic deposition current density of the composite coatings increases when SiC par-ticles and rare earth (RE) were added in the bath, which is profitable for Ni- W-P alloy to deposit in the cathod, forming Ni-W-P-SiC and RE-Ni-W-P-SiC composite coatings. On the contrary, the addition of PTFE in the bath decreases cathodic deposition current density of the coatings. The current density increases a little when the amount of RE is 7-9g/l; however, the current density increases greatly when the amount of RE is increased to 11-13g/l. Bui ij the amount of RE is raised further, the current density decreases. Hardness and wear resistance of RE-Ni-W-P-SiC composite coating have been studied, and the results show that the hardness and wear resistance of RE-Ni-W-P-SiC composite coating increase with increasing heat treatment tempera-ture, which reach peak values at 400℃; while the hardness and wear resistance of the coating decrease with the rise of heat treated temperature continuously.
文摘The formation of ceramic coatings on metal substrate by cathodic electrolytic deposition (CELD) has received more attention in recent years. But only thin filmscan be prepared via CELD. Yttrium stabilized zirconia (YSZ) ceramic coatings were deposited on FeCrAI alloy by a novel technique--cathodic micro-arc electrodeposition (CMED).The result shows that, when a high pulse electric field is applied to the cathode which was pre-deposited with a thin YSZ film, dielectric breakdown occurs and micro-arc discharges appear. Coatings with reasonably thickness of-300μm and crystalline structure can be deposited on the cathode by utilizing the energy of the micro-arc. The thickness of the as-deposited coating is dominated by the voltage and the frequency. Y2O3 is co-deposited with ZrO2 when Y(NO3)3 was added to the electrolyte, which stabilize t-phase, t′-phase and c-phase of ZrO2 at room temperature. The amount of the m-ZrO2 in the coating is diminished by increasing the concentration of Y(NO3)3 in the electrolyte.This report describes the processing of CMED and studies the microstructure of the deposited YSZ coatings.
文摘 为了更深入地探讨Zn Fe SiO2复合镀层的电沉积机理,采用三电极体系下的动电位法测定了电沉积Zn Fe SiO2复合镀层的阴极极化曲线,并研究了镀液成分对阴极极化的影响。结果表明,Zn Fe SiO2复合镀层的沉积属于异常共沉积,而且SiO2微粒的加入对Zn Fe SiO2镀层复合电沉积的阴极极化行为影响不大。
基金sponsored by the New-star Program of Beijing Science and Technology Committee(No.9558102500)National Scientific Research Foundation for the Returned Overseas Chinese ScholarsBeijing Scientific Research Foundation for the Returned Overseas Chinese Scholars
