In the project area B the applicability of the classical production processes and their influence on the microstructure and the characteristics of Fe-Mn-C alloys is examined. Here the focus is put, aside from the experimental simulations of solidification, on the warm and cold forming processes as well as on annealing processes and their numerical simulations.
The experimental simulation of solidification in the Fe-Mn-C system takes place in the solidification lab of the institute for metallurgy in sub-project B1. For that, alloys will be produced and submitted to different cooling rates. In addition, the hot forming in sub-project B2 can be carried out immediately after the solidification. By means of light- and electro-microscopic analysis carried out in sub-project C1, the relevant structure characteristics of the Fe-Mn-C alloy will be described quantitatively. The results serve for the support and the validation of the ab initio based calculations on the solidification- (A4) and formability (A7) behavior.
The examination of the forming processes (hot forming with and without intermediate reheating treatment, cold forming to semi-finished products) takes place on the experimental and numerical level of sub-project B2. Following the experimental representation and the parameter formulation, the development of simulation models occurs, which allow to investigate the macroscopic material behavior with specific integration of metal physical phenomena. This aims at the fact, that the processing characteristic of steel on a macroscopic level can be traced back to metal physical mechanisms. Furthermore data for the validation of the high temperature charts for A5 are provided with this. The hot and cold rolled material will be used for the examination of the mechanical characteristics in C2.
The simulation of recrystallisation and gain growth during thermal treatment, which will be carried out in B4, is based on the energies and the mobility of grain boundaries and triple lines. They make predictions about morphology, texture and grain size distribution possible. These will be compared and checked with the corresponding and experimentally determined data in the Fe-Mn-C system. The process window of recrystallisation of the Fe-Mn-C alloys will be worked out and the parameters for the annealing passed onto the sub-project A5.
Subprojects of Division B