Abstract
Aluminum casting/forging process is used to produce an aluminum tie-rod end for the steering system of automobiles. Firstly, casting experiments were carried out to get a good preform for forging the tie-rod end. In the casting experiment, the effects of additives, Ti+B, Zr, Sr, and Mg, on the mechanical properties and the microstructure of a cast preform were investigated. And a finite element analysis was performed to determine an optimal configuration of the cast preform. Lastly, a forging experiment was carried out to make the final product of aluminum tie-rod end by using the above cast preform. In the casting experiments, when 0.2% Ti+B and 0.25% Zr were simultaneously added into molten Al-Si alloy, the highest values of tensile strength and elongation of the cast preform were obtained. When 0.04% Sr were added into the molten aluminum alloy, the finest silicon-structure was observed in the cast preform. The highest hardness was obtained when 0.2% Mg was added. In the forging experiment, It was confirmed that the optimal configuration of a cast preform predicted by FE analysis was very useful. The hardness of a cast/forged product using designed preform was superior to that of required specification.
