Research On The Preparation And Thermal Storage Preperties Of High-Temperature Phase Change Thermal Storage Al-Si-Cu-Mg-Zn Alloy

With the solar thermal electricity technology,thermal storage technology has attracted increasing attention.Phase change metal with high energy storage density, low condenser depression,high thermal conductivity,phase-change again with the long-term stable,easy to control,has a wide range of application in high-temperature thermal storage.The high-temperature phase change Al-Si-Cu-Mg-Zn alloy in the phase transition temperature,density storage,operating life in areas such as more suitable for solar thermal power generation system of thermal storage materials.In this thesis,20 different components of the Al-Si-Cu-Mg-Zn series phase-change thermal storage aluminum alloy materials are designed and prepared. Using micro-technology,liquid method,integrated thermal analysis,The microstructure,density,phase change temperature,latent heat per gram,sensible heat per gram,the thermal storage per gram,latent heat per cubic centimetre,sensible heat per cubic centimetre and total energy storage per cubic centimeter,and other properties of these phase change aluminium alloy materials were studied.A variety of phase change aluminum alloy materials with phase transition temperature in the 400-800℃,phase-change latent heat over 200J / g,high-energy storage in volume which is for power generation solar thermal systems use are prepared.Al-Si series thermal storage aluminum alloys have higher phase-change latent heat.Al-Si eutectic composition has the highest latent change heat about 450J / g. When the aluminum alloy in the Mg,Zn content increases,lower heat per unit mass of material phase-change latent heat.As the phase-change latent heat in volume,the Al-Si eutectic alloy composition of the thermal storage materials about 1233.8J/cm~3, still higher than other components of the heat storage material of aluminum alloy.Between 400-800℃,the composition of aluminum alloy sensible heat storage pergram is not very different,but the increase in Cu will help improve the ability of sensible heat storage.Due to large differences in density,Al-Si series aluminum alloy materials storage of volume is not high.The aluminum alloy with Cu,Zn has higher sensible heat storage of volume than other aluminum alloy.Al-Si series aluminum alloys have higher heat storage per gram in 400-800℃than other aluminium alloy.However,the thermal storage on volume,aluminium alloy with more Cu,Zn is superior to other components of aluminum alloy.Given these factors,the aluminium alloy with Cu,Zn alloy suit solar thermal tower power generation systems in the ability on heat storage.