COMPARISON OF METHODS FOR PREDICTING THE EVOLUTION OF DAMAGE DURING METALFORMING

摘要

a; Unsoundness due to porosity in steel may arise, following casting, as a result of shrinkage during cooling or because of reduced solubility of gases such as hydrogen. In order to control the level of unsoundness it is necessary to understand its nature/extent and to model its evolution during metalforming processes such as hot rolling. The development of damage can be analysed on 4 levels viz., in terms of increasing sophistication, (a) macroscopic or bulk, (b) mesoscopic, (c) microscopic and (d) atomistic. Corresponding models that have been used or potentially could be developed for the investigation of processes such as hot rolling or forging are outlined and compared in this paper. The paper also presents some ideas on the way forward for model development in order to understand the mechanism of damage and optimise its control.