Research of surface wettability of plating on the ceramic shell
The wettability of coating surface has important significance in the spreading situation of piece of sticky piece, and the welding state of Au-Sn solder. Wettability of solids is expressed with wetting contact angle. In this paper, by studying the wetting angles of the water droplets on the surface of the different ceramic shell, assess the wettability on the surface of the ceramic shell, and the ways to improve the wettability is proposed through experiments. The results of the experiment show that the presence of organic matter reduces the wettability of the coating surface, so the wetting angles of the coating surface are large in the analysis process. After the plasma cleaning, organics were washed subsequently, and the wettability of the surface coating increased, so the wetting angles are decreased.
The wetting behaviour of several organic liquids in water on coal surfaces
Abstract Several organic liquids were used to probe the surface chemical characteristics of five coal types ranging in rank from brown to low-volatile bituminous in the presence of water. The liquids were hexane, cyclohexane, diiodomethane, toluene, o-xylene, chloroform, dichloromethane, oleic acid, chloroform and hexan-1-ol. The advancing and receding contact angles formed at the coal-water-liquid junction were measured and it was found that a critical interfacial tension existed, below which the organic liquid wetting properties were equivalent. Above the critical interfacial tension, the wettability of the coal by the organic liquid increased as the polarity of the liquid increased, giving a measure of the efficiency with which the water wetting film could be expelled from the coal surface. At a fixed interfacial tension, the advancing and receding contact angles decreased as the rank of the coal increased.
SR topography of plastically deformed Fe-Si bicrystals - observation in situ and post mortem
SR reflection topography was applied to study the interaction of slip dislocations with the grain boundaries in Fe-4at%Si bicrystals deformed by compression. Three experimental settings with either a white or monochromatic beam were used and the corresponding orientation contrast analysed. Dislocation transmission through the grain boundary was observed in bicrystals with favourable geometry of the slip systems.