The economic loss caused by liquid metal corrosion to China's metallurgical industry is very serious, and there is also a potential threat to the normal operation of nuclear power stations. Thermal spraying technology has more than 80 years of development history, its application fields are very wide. The technology has been successfully applied in anti-corrosion, which has extended the service life of the workpiece, reduced the generation cost of the enterprise and the maintenance cost of the equipment, and played an indispensable role in the development of national economy.In the field of liquid metal corrosion resistance, China has done a lot of long-term and research work, especially in the metallurgical industry components (including large cold and hot rollers), from equipment materials and processes, have entered the engineering application stage, and achieved significant technical and economic benefits. In recent years with the development of thermal spraying technology and related materials, process and improve, this technology is also referenced to corrosion resistance to molten metal engineering, domestic related units and some colleges also did a lot of work, such as in material aspect, has successfully developed the can be used in corrosion resistance to molten metal to 3 oxidation 2 aluminium (Al2O3) as the main products of oxidation ceramic series thermal spraying powder materials, some units also have copied out of the plasma, supersonic thermal spray equipment and plasma equipment, the supersonic electric arc, basic comparable to similar foreign products in performance.Want to know more about liquid metal corrosion?-> Liquid metal corrosion methods and mechanisms
Liquid metal filling process is the first stage of casting formation in which many defects of the casting are formed.This process must be mastered and controlled in order to obtain high quality sound castings.To this end, the ability of liquid metal to fill the mold is studied in order to obtain a fully formed, well-defined casting to prevent defects in the mold filling phase.The ability of a liquid alloy to fill the mold cavity to form a well-defined, well-formed, high-quality casting is called the fluidity of the liquid alloy and the filling capacity.The better the fluidity of the liquid alloy, the easier it is to cast clear, thin and complicated shapes, and the more the liquid alloy can be supplemented when it contracts in the mold, the more the gas and non-metallic inclusions in the liquid alloy can float up and get rid of.If the fluidity is not good, it is easy to cause casting to produce defects such as under casting, cold isolation, porosity, slag inclusion and shrinkage.Liquid metal filling casting is a complex physical, chemical and hydrodynamic problem, which involves various properties of liquid metal, such as density, viscosity, surface tension, oxidization, oxide properties and wettability.The size of filling capacity affects the forming of casting, and the alloy with poor filling capacity is difficult to obtain large, thin - walled, sound casting with complex structure. The factors that affect mold filling function through two ways: one is to influence the heat exchange condition between the metal and the mold, thus changing the flow time of the liquid metal; The other is to influence the hydraulic conditions of the liquid metal in the casting, so as to change the flow rate of the liquid metal.