A DUCTILE-DAMAGE MODEL AND ITS APPLICATION TO METAL-FORMING PROCESSES

In order to reveal the evolution of ductile damage during plastic-working processes and to ensure the quality of the product, the formulation of a ductile-damage model has become an urgent need in plastic-working theory. In this paper, a ductile-damage model based on the precise measurement of relative density changes is presented, the rationality of the proposed model being verified through observation of the change in the volume fraction of voids during the tensile test, by the use of scanning electron microscopy. An example to demonstrate the application of the model is given. Combining the proposed model with a proper method of the analysis of metal-forming processes, it is possible to predict the evolution of ductile damage in the interior of the workpiece and thus the workability of the material.