An automatic brush-plating system was developed for component remanufacturing. With this system, Ni/nano-alumina composite coatings from an electrolyte containing 20g/L nano-alumina particles were prepared. Microstr...An automatic brush-plating system was developed for component remanufacturing. With this system, Ni/nano-alumina composite coatings from an electrolyte containing 20g/L nano-alumina particles were prepared. Microstructure, surface morphology, microhardness and wear resistance of automatically plated coatings and manually plated coatings were investigated comparatively. The results show that the automatically plated coatings are relatively dense and uniform and have lower friction coefficient of 0.089 under lubricant condition, when compared with manually plated coatings with friction coefficient of 0.14.展开更多
In this study, two thermal barrier coatings based on YSZ were produced by using a commercially available agglomerated and sintered powder and a special spray powder prepared by high energy ball milling. Both thermal b...In this study, two thermal barrier coatings based on YSZ were produced by using a commercially available agglomerated and sintered powder and a special spray powder prepared by high energy ball milling. Both thermal barrier coatings exhibited similar overall porosities, but significantly different microstructures. Application of the special spray powder prepared by high energy ball milling led to a microstructure with numerous inclusions of semi-molten agglomerates, which introduced a plethora of clusters of fine pores into the coating and several more microstructural defects. This microstructure resulted in a significantly better thermal shock behavior compared to the conventional thermal barrier coating. The heat treatment of both thermal barrier coatings atθ=1150℃for t=100 h led to a sintering of both coatings. The results were reduced overall porosity and significantly increased fracture toughness. A correlation between the fracture toughness of both coatings after the heat treatment and the thermal shock life time could not be identified.展开更多
文摘An automatic brush-plating system was developed for component remanufacturing. With this system, Ni/nano-alumina composite coatings from an electrolyte containing 20g/L nano-alumina particles were prepared. Microstructure, surface morphology, microhardness and wear resistance of automatically plated coatings and manually plated coatings were investigated comparatively. The results show that the automatically plated coatings are relatively dense and uniform and have lower friction coefficient of 0.089 under lubricant condition, when compared with manually plated coatings with friction coefficient of 0.14.
基金the German Science Foundation (DFG) for financially supporting the research work within the scope of the DFG projects ZH205/2-1 and BO1979/32-2
文摘In this study, two thermal barrier coatings based on YSZ were produced by using a commercially available agglomerated and sintered powder and a special spray powder prepared by high energy ball milling. Both thermal barrier coatings exhibited similar overall porosities, but significantly different microstructures. Application of the special spray powder prepared by high energy ball milling led to a microstructure with numerous inclusions of semi-molten agglomerates, which introduced a plethora of clusters of fine pores into the coating and several more microstructural defects. This microstructure resulted in a significantly better thermal shock behavior compared to the conventional thermal barrier coating. The heat treatment of both thermal barrier coatings atθ=1150℃for t=100 h led to a sintering of both coatings. The results were reduced overall porosity and significantly increased fracture toughness. A correlation between the fracture toughness of both coatings after the heat treatment and the thermal shock life time could not be identified.
