The fitting method is used for obtaining the constitutive relation of ultra-high strength steel in this paper. At the same time, the forming limit of material is researched under different de/brmation conditions. Thro...The fitting method is used for obtaining the constitutive relation of ultra-high strength steel in this paper. At the same time, the forming limit of material is researched under different de/brmation conditions. Through experiments, the paper obtains stress-strain curve under different deformation temperatures and strain rates. On the basis of experimental data, the constitutive relation model is established which can reflect the de- fomlation capacity of ultra-high strength steel during process of hot stamping. Combining with finite element simulation results of hot stamping by the commercial software AUTOFORM, transfer path of load and matching law of strength, the paper determines the design criteria and forming process requirements of parts manufactured by hot stamping. Through setting different process parameters, such as punch velocity and friction coefficient, and blank shape, the paper finds that process parameters and blank shape have an essential effect on the quality of parts.展开更多
文摘The fitting method is used for obtaining the constitutive relation of ultra-high strength steel in this paper. At the same time, the forming limit of material is researched under different de/brmation conditions. Through experiments, the paper obtains stress-strain curve under different deformation temperatures and strain rates. On the basis of experimental data, the constitutive relation model is established which can reflect the de- fomlation capacity of ultra-high strength steel during process of hot stamping. Combining with finite element simulation results of hot stamping by the commercial software AUTOFORM, transfer path of load and matching law of strength, the paper determines the design criteria and forming process requirements of parts manufactured by hot stamping. Through setting different process parameters, such as punch velocity and friction coefficient, and blank shape, the paper finds that process parameters and blank shape have an essential effect on the quality of parts.