Research On Homogeneity Control Of Microstructure And Mechanical Properties For Aluminum Alloy Wheel Prepared By Liquid Die Forging

Liquid die forging is a near-net shaping technology, which can form complex parts with mechanical properties close to those of forging parts, and will establish a new method for making such complicated parts. In this paper, a load wheel with material 2A50 aluminum alloy was studied; inhomogeneity strain field existed in the solidification process of the load wheel was studied by numerical simulation and liquid die forging with simple loading, the inhomogeneity of microstructure and properties of the workpiece prepared by liquid die forging with simple loading was researched and analyzed, the rule of influence of local load feeding on the homogeneity of microstructure and properties of the workpiece was studied by forming experiments with complex loadingAs is known from simulation of solidification process of load wheel workpiece By ProCAST software , solidification sequence of different parts of the workpiece inconsistent, the straight wall and the bottom of the corner of the workpiece is the last to solidify.; the maximum tensile stress around the corner is the largest, which is the largest parts of hot concentration, therefore this area is likely to occuer shrinkage and thermal cracking and other defects.Defects and their resulting position by the simple loading liquid die forging experiments are in accordance with the prediction of simulation, microstructure and properties of the workpiece formed in this manner are inhomogeneity.The geometry of grains in the straight wall is less regular and inhomogeneity,bigger than that of grains in the bottom part, the density and mechanical properties of the straight wall is lower than that of the bottom.A load wheel with homogeneity microstructure and properties can be formed by the complex loading - local feeding method. Defects (shrinkage cavities and cracks, etc.) of the workpiece gradually disappear with the increase of feed shrinkage;the microstructure of workpiece becomes homogeneity; the density and mechanical properties of the straight wall increases to nearly the same as that of the bottom,and mechanical properties of the workpiece gets homogeneity when feed shrinkage is 8 ~ 10mm. From the experimental results available, feed shrinkage of 10mm is the ideal feeding parameter.A load wheel with homogeneity microstructure and mechanical properties was obtained by complex loading, which provides a method of controlling homogeneity of microstructure and mechanical properties of workpieces prepared by liquid die forging.