A new type additive was added to the non-self-fluxing copper powdered alloy, and the powder showed satisfactory performance of spraying and fusing, self-protecting, and self-fluxing in the oxygen-acetylene flame spray...A new type additive was added to the non-self-fluxing copper powdered alloy, and the powder showed satisfactory performance of spraying and fusing, self-protecting, and self-fluxing in the oxygen-acetylene flame spraying and fusing process. The additive was melted and could absorb copper oxide when spraying, then it created a layer of film to cover the copper liquid, which protected the copper liquid from oxidizing efficiently and promoted it wetting on iron surface. Thus it lead to real diffusion between Cu and Fe, which resolved the diffwulty of combining Cu with Fe and reduced the limitation of the powder, and it promoted the usage value of general powder. Through analysis of microstructures, it was found that the fastness and compactness of the combining interface was excellent as well as the diffusing of transition area, and the hardness was suitable, which meant that the performance could meet the needs of high quality valves completely.展开更多
The extensive intrusion （covering an area of 83.7-238.3 km;and accounting for 18.6-31.5% of the total area of the plain）, the presence of a transitional zone 1.5-6.0 km in width, and the interconnection in distribut...The extensive intrusion （covering an area of 83.7-238.3 km;and accounting for 18.6-31.5% of the total area of the plain）, the presence of a transitional zone 1.5-6.0 km in width, and the interconnection in distribution between the seawater intrusion district and the region lower than the sea level caused by the strong drop of the groundwater level are major characteristics of the seawater intrusion in the study area. Cation exchange played an important role during the formation of chemical composition of the groundwater in the seawater intrusion district.展开更多
文摘A new type additive was added to the non-self-fluxing copper powdered alloy, and the powder showed satisfactory performance of spraying and fusing, self-protecting, and self-fluxing in the oxygen-acetylene flame spraying and fusing process. The additive was melted and could absorb copper oxide when spraying, then it created a layer of film to cover the copper liquid, which protected the copper liquid from oxidizing efficiently and promoted it wetting on iron surface. Thus it lead to real diffusion between Cu and Fe, which resolved the diffwulty of combining Cu with Fe and reduced the limitation of the powder, and it promoted the usage value of general powder. Through analysis of microstructures, it was found that the fastness and compactness of the combining interface was excellent as well as the diffusing of transition area, and the hardness was suitable, which meant that the performance could meet the needs of high quality valves completely.
基金This paper is the State key scientific research project 75-57-01-02-05 funded by the National Natural Science Foundation of China. Participating in the field work of the project were also Liu Coufan. Li Chunwei. Zou Zeyuan, Lin Jun, Ren Peiqi, Jiang Kehu
文摘The extensive intrusion （covering an area of 83.7-238.3 km;and accounting for 18.6-31.5% of the total area of the plain）, the presence of a transitional zone 1.5-6.0 km in width, and the interconnection in distribution between the seawater intrusion district and the region lower than the sea level caused by the strong drop of the groundwater level are major characteristics of the seawater intrusion in the study area. Cation exchange played an important role during the formation of chemical composition of the groundwater in the seawater intrusion district.
