The constitutive relationships of Al-Mg-Si alloy deformed at various strain rates,temperatures and strains were studied.The microstructure evolution was quantitatively characterized and analyzed,including recrystalliz...The constitutive relationships of Al-Mg-Si alloy deformed at various strain rates,temperatures and strains were studied.The microstructure evolution was quantitatively characterized and analyzed,including recrystallization fraction,grain sizes,local misorientation,geometrically necessary dislocation and stored strain energy during hot deformation and subsequent heat treatment.The results show that the dislocation density and energy storage are linear with ln Z during hot deformation and subsequent heat treatment,indicating continuous recrystallization occurring in both processes.With higher ln Z,the dislocation density declines more sharply during subsequent heat treatment.When ln Z is less than 28,dislocation density becomes more stable with less reduction during subsequent heat treatment after hot deformation.As these dislocations distribute along low angle grain boundaries,the subgrain has good stability during subsequent heat treatment.The main recrystallization mechanism during hot deformation is continuous dynamic recrystallization,accompanied by geometric dynamic recrystallization at higher ln Z.展开更多
基金Project(2016YFB0300901)supported by the National Key R&D Program of ChinaProject(TC190H3ZV/2)supported by the National Building Project of Application Demonstration Platform on New Materials Products,ChinaProject(15308469779)supported by Key Laboratory of National Science and Technology for Equipment Pre-research,China。
文摘The constitutive relationships of Al-Mg-Si alloy deformed at various strain rates,temperatures and strains were studied.The microstructure evolution was quantitatively characterized and analyzed,including recrystallization fraction,grain sizes,local misorientation,geometrically necessary dislocation and stored strain energy during hot deformation and subsequent heat treatment.The results show that the dislocation density and energy storage are linear with ln Z during hot deformation and subsequent heat treatment,indicating continuous recrystallization occurring in both processes.With higher ln Z,the dislocation density declines more sharply during subsequent heat treatment.When ln Z is less than 28,dislocation density becomes more stable with less reduction during subsequent heat treatment after hot deformation.As these dislocations distribute along low angle grain boundaries,the subgrain has good stability during subsequent heat treatment.The main recrystallization mechanism during hot deformation is continuous dynamic recrystallization,accompanied by geometric dynamic recrystallization at higher ln Z.