7050铝合金模锻件组织均匀性的低温小变形调控及模型构建

Microstructure homogeneity regulation with small deformation at low temperature and model construction of 7050 aluminum alloy die forgings

为解决大型铝合金航空结构件在传统热模锻工艺下出现的表层和心部组织不均匀问题,采用低温小变形工艺对锻件的组织均匀性进行了调控。利用热/力模拟试验机和电子背散射衍射等实验手段研究了低温小变形工艺和固溶处理对高强铝合金锻件晶粒组织演变的影响规律,并建立了包含位错密度参数的7050铝合金锻件表层静态再结晶模型。利用模型计算所得的静态再结晶体积分数与实验值吻合程度较高,说明所建立的静态再结晶模型能够准确描述7050铝合金锻件表层的静态再结晶行为。

To solve the problem that the microstructures of surface and core of large aluminum alloy aerospace structures parts are inhomogeneous in the traditional hot die forging process,the small deformation process at low temperature was adopted to regulate the microstructure homogeneity of forgings.The influence of small deformation process at low temperature and solution treatment on the grain microstructure evolution of high strength aluminum alloy forgings was investigated by means of thermo-mechanical simulator and electron back-scatter diffraction,and the static recrystallization model of surface of 7050 aluminum alloy forgings including dislocation density parameters was established.The static recrystallization volume fraction calculated by the model is in a good agreement with the experimental values,which indicates that the established static recrystallization model can accurately describe the static recrystallization behavior of surface of 7050 aluminum alloy forgings.