两道次成形过程中拉伸速度及热处理对2A12-O铝合金晶粒尺寸的影响

Effects of Tensile Speed and Heat Treatment on Grain Size of Aluminium Alloy in Two-step Deformation

目的研究铝合金2A12材料在两道次变形过程中拉伸量、拉伸速度及热处理参数对材料晶粒尺寸的影响规律。方法进行了2A12-O铝合金板的"预拉伸-退火-再拉伸-淬火"两道次成形过程。当两次拉伸量相等,总拉伸量不大于20%时,研究了拉伸速度、退火温度、淬火保温时间与试验后晶粒尺寸的关系。结果在拉伸总量较小的情况下,拉伸速度和各热处理参数对材料最终晶粒尺寸的影响较大;当拉伸总量增大到某临界值时,拉伸速度和热处理参数的影响明显减小,各参数下的晶粒尺寸在总拉伸量相同的情况下趋于一致。结论获得了拉伸总量、拉伸速度、退火温度和淬火保温时间等成形及热处理参数对2A12-O铝合金板材晶粒尺寸的影响规律,为该材料成形及热处理过程中的晶粒尺寸控制提供了依据。

The paper aims to study the effects of tensile amount, tensile speed and heat treatment parameters on the grain size of 2 A12 aluminium alloy during two-step deformation. Through the two-step forming process of prestretching-annealing-poststretching-quenching, the relationship between the grain size and the parameters of tensile speed, annealing temperature, holding time of quenching was studied when the tensile amounts of the two deforming steps were equal and the total tensile amount was not more than 20%. When the total tensile amount was small, the tensile speed and heat treatment parameters had great influence on the final grain size of the material. And when the total tensile amount was increased to a certain critical value, the influence of the parameters was obviously reduced, and the grain size under each parameter tended to be the same when the total tensile amount was the same. The effects of forming and heat treatment parameters on the grain size of 2 A12-O aluminum alloy sheet are obtained. It provides a basis for grain size control of aluminium alloy sheet during forming and heat treatment.