Die fatigue life design and assessment via CAE simulation

In die design process, the design and prediction of die fatigue life is a non-trivial issue. Many factors in die life cycle from design, fabrication to service all affect die life. The die life in cold forging processes is basically determined by die fatigue failure. The design and assessment of die fatigue life needs to consider all the affecting factors including die structure and component design, materials selection and properties configuration, die fabrication and service conditions. Currently, there is no efficient approach to providing complete solutions by considering all of these factors. CAE simulation technology, however, presents a promising approach to addressing the issue. In this paper, a simulation-based approach for die life design and assessment is presented. The approach employs both stress-life and strain-life fatigue analysis methods to conduct the die fatigue life design and analysis based on the stress and strain revealed by CAE simulation. As the die stress and strain in forming process vary dynamically, the integrated simulation of forming process and die deformation is conducted in such a way that the dynamic die stress and strain can be identified and determined. To implement this idea, a realization framework is orchestrated and the processes and procedure under the framework are succinctly articulated. The implementation with case studies is finally used to test and verify the validity, robustness, and efficiency of the developed approach. The approach is proven to be able to provide satisfactory solutions for die life design and assessment in the early stage of die design.

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