铸造铝合金轮毂的热处理工艺与组织性能研究

Study on Heat Treatment Process, Microstructure and Properties of Casting Aluminum Alloy Wheel

研究了固溶和时效热处理以及涂装对A356合金轮毂的力学性能和显微组织的影响,并对拉伸断口形貌进行了观察。结果表明,A356合金轮毂适宜的热处理工艺为:固溶温度为530℃、固溶时间为3 h、淬火温度为60℃、淬火时间为120 min、时效温度为160℃和时效时间3 h;铸态A356合金轮毂由初生α-Al枝晶和不均匀分布的共晶硅相组成,T6和T6+涂装态A356合金中的共晶硅相发生球化,尺寸相对较小且分布更加均匀;A356合金轮毂的抗拉强度和断后伸长率从高至低依次为T6+涂装态、T6态、铸态。

The effect of solution and aging heat treatment, painting process on the mechanical properties and rnierostructure of A356 alloy wheel was studied, and the tensile fracture morphology was also observed. The results show that the suitable heat treatment process of A356 alloy wheel as follows; the solid solution temperature is 530 ℃, the solution time is 3 h, the quenching temperature is 60 ℃, the quenching time is 120 min, the aging temperature is 160 ℃ and the aging holding time is 3h. The microstructure of as-Cast A356 alloy wheel is composed of primary α-Al dendrites and non-uniformly distributed cutestic silicon phases; euteetic Si phases in T6 and T6＋ painting A356 alloys become spheroids, and its size is relatively small and the distribution is more uniform. The tensile strength and elongation of the A356 alloy wheel from high to low is T6＋ painting, T6 and as-cast state.