Numerical Simulation of Solidification Microstructure of Non-Heat-Treated Al-Mg-Si Aluminum Alloy by Squeeze Casting
Numerical investigation on solidification microstructure of a new-type non-heat-treated Al-Mg-Si aluminum alloy during squeeze casting was carried out.The results of macroscopic numerical simulation show that the solidification sequence of the casting with variable cross-section is middle lower part,middle upper part,top part and bottom part;with the increase of pouring temperature or mold temperature,shrinkage volume fraction firstly decreases and then increases,and when the pouring temperature is 700 ℃ and the mold temperature is 475 ℃,the shrinkage volume fraction is the smallest;with the increase of squeeze casting pressure,the shrinkage volume fraction decreases,and the shrinkage volume fraction is the smallest at 100 MPa.The microstructure numerical simulation results show that the microstructure at the bottom and middle and upper parts of the casting are coarser,and smaller at the middle and lower parts and top parts,which is related to the wall thickness and the degree of supercooling.