Effect of squeezing casting technology on structures and properties of air-conditioner swaying tray

The air-conditioner swaying tray of automobile made of 4A11 aluminum alloy was manufactured by squeezing casting technology.When the pouring temperature is 740℃,the preheating temperature of the die set is 280℃ and the applying pressure is 1900kN(139.45MPa),the mechanical property of swaying tray is the finest.Under the condition of the optimal technological parameters,the tensile strength,Vickers hardness(HV_(0.1)) and(elongation) of swaying tray reach 310330MPa,HV100110,9%,respectively.The microstructures of swaying tray are fine,Si grains are uniformly distributed and no phenomena of coarsening are observed,and the surface and inside of swaying tray have no cold shut,gas cavity,shrinkage cavity and crack,etc.By means of analyzing tensile fractures,the importing pieces and the pieces with the optimal technological parameters both have the fracture characteristics of the dimple.The number of dimples of the importing pieces are greater,so the plasticity is higher.The dimples of the pieces with the optimal technological parameters are bigger.