Research On Melt Treatment Processing Of ZL114A Aluminum Alloy And Centrifugal Casting Processing Of Impeller

ZL114A alloy is Al-Si hypoeutectic alloy. ZL114 A alloy with low-density and high strength-weight ratio is department of Al-Si hypoeutectic alloy. It is an important material in modern industry, such as aviation, aerospace, automotive, machinery and other industries. ZL114 A alloy's mainly casting technique is Counter-pressure Casting, Investment Casting and centrifugal casting. The centrifugal casting process is simple process, high efficiency and the castings' compact microstructure. The casting prone to shrinkage and porosity, when the solidification process of casting is in centrifugal force. These defects lead to its application is limited. Aluminum alloy melt processing and centrifugal casting process can reduce casting defect and improve the aluminum alloy microstructure. It has great significance.This paper mainly analyzes the microstructure of aluminum alloys for aerospace ZL114 A with the melt processing technology and the centrifugal casting process. This experiment study the microstructure of ZL114 A alloy melts treatment with metallographic microscopy and density analysis. The effect of ZL114 A microstructure refining was discussed in a variety of the centrifugal casting.Melt-treatment process test is mainly analyzes the experimental parameters of refining agent, degassing agents and isothermal holding time. The secondary dendrite arm spacing gradually become smaller branch with the quality score of refined agent and degassing agents increasing. Then, increasing the addition of refiner and degassing agents will reduce the refinement instead. Alloy secondary dendrite arm spacing is the same first decreases and then increases, with the extension of isothermal holding time. The best degassing effect occur the addition of degassing agents is 1.5%. When the alloy's quality score of refined agent was 1% can result in the best degassing effect. But considering the refinement and modification effect, the isothermal holding time is 30 min to be the most appropriate.The microstructure and surface quality of ZL114 A and the effect of degassing was analyze in different centrifugal casting process. The shell to the preheating temperature is too high, the alloy liquid's heat emission rate decreased. This leads to slow down the solidification of the alloy liquid alloy and makes the alloy dendrites become thick. Shell mold preheat temperature is too low result in adverse filling process. This will result in misrun, cold shuts et al. Therefore, preheat temperature of the shell is 500?. Centrifugal casting process experiment mainly analyses parameters of different mold centrifugal speed, casting states and exhaust hole etc. Liquid level will be disturbances when the shell pours in certain centrifugal speed. The casting increases the possibility of Gas Entrapment, Inclusions and cold shuts. Liquid metal was rise very smooth when the shell pours static. The casting reduces the possibility of Gas Entrapment, Inclusions and cold shuts. Exhaust hole set up in the shell will contribute to the discharge of gas from casting mold and improvement of casting quality.