On the basis of the fracture model and the deep drawing deformation force. The fracturelimit prediction and control criterion is calculated.
根据破裂模型和拉深变形力，导出了破裂极限预报与控制判据。
2
According to diffuse instability criterion, worked out the principle of verdicting the case of base fracture or side fracture and formulae of fracturelimit BHF;
按照分散性失稳准则，推导出产生壁裂和底裂的判别条件和方盒形件成形过程中的极限压边力公式；
3
When the applied load exceeds the limit strength of the material as a result of parts breaking overload fracture.