Prediction of Potential Fracturing During Radial-Shear Rolling of Continuously Cast Copper Billets by Means of Computer Simulation

Abstract

Based on the results of experimental radial-shear rolling of continuously cast anodic copper billets (rods) using a 10-30 mini-mill at 750 and 850°C, a part-through fracturing from within the billets has been discovered. The volume of cavities formed as a result of such fracturing appears to be more significant at 750°C. A simulation of rolling under experimental conditions was performed using DEFORM software, and the efficiency of applying a finite-element analysis computing environment for predicting fracturing was evaluated. An adequate correlation was established between the obtained estimates of the metal ductility under different deformation temperatures, as well as the probability of formation and dimensions of discontinuities and experimental data. The comparison between the shrinkage cavity depths of the billets based on the results of computer simulation has shown that the ductility of the rod material is higher at 800°C. Based on the analysis of variation in values of the rigidity coefficient under stress condition along the radius of the billet near the end of it, as well as analysis of the path described by the points located along the billet radius in the “cumulative deformation – rigidity coefficient under stress condition” coordinates while in the deformation zone, obtained as a result of computer simulation, it has been established that fracturing at 750°C should be more significant than at 800°C. Recommendations are provided regarding further use of the results of computer simulation to estimate the size of the regions, within which fracturing is expected to occur under the given rolling conditions.