A simple Lagrange-an traveling slice model has been applied for the prediction of the relations between process parameters, macrosegregation and solidification grain structure formation (equiaxed to columnar and columnar to equiaxed transition) during the continuous casting process of steel billets. The main advantage of the slice model is its very fast calculation time in comparison with the complete 3D heat and fluid flow model which might need calculation time, measured in days. The slice models thus allows for fast optimisation and even for on-line simulation. The heat and species transfer models are based on the mixture continuum assumptions with Lever solidification rule and enhanced thermal and solutal diffusivities for heuristic accounting of fluid flow effects. The grain structure evolution model is based on the Gaussian nucleation rule, and KGT growth model, coupled to the macroscopic heat and species transfer models. The heat and species transfer models are solved by the meshless technique by using local collocation with radial basis functions. The grain structure evolution model is solved by the point automata technique, a novel meshless variant of the cellular automata method. A comparison of the results with the experimental data for steel grade 51CrV4 is shown in terms of macrosegregation and grain structure across the billet. Simulations and comparisons have been carried out for nominal casting conditions, reduced casting temperature, and reduced casting speed. The model predicts surprisingly well the qualitative features of the macrosegregation and grain structure patterns. Possible refinements of the model with respect to other physical mechanisms are discussed. The paper has been presented on most prominent conference on solidification MCWASP.
F.06 Development of a new product
COBISS.SI-ID: 2417659We describe further development of model of the hot rolling of steel, developed for Štore Steel company in the paper, presented at the European Conference on Applied Sciences and Engineering, largest conference of this type in Europe in 2012. The model of hot rolling consists of the coupled thermal model, mechanical model and model for node positioning and manipulation. We present rolling of square steel billet to circular bar. The extended version of the paper has been submitted to the topmost journal CMES.
F.10 Improvements to an existing technological process or technology
COBISS.SI-ID: 2649339Prof.dr. Božidar Šarler has highlighted the development of new materials for automotive industry in Slovenia in the framework of invited lecture at the 9. Nanotechnological day, 27.11.2012 at the Chamber of Craft and Small Business of Slovenia. We have summarized the work performed in the framework of the present project L2-3651 programe group P2-0379, and collaboration with the Center of Excellence for Biosensors, Instrumentation and Process Control as well as industrial research groups in the area of development of new steels, aluminum alloys and epoxi composites with addition of nano-particles. We have stressed the importance of the connections between simulations, laboratory experiments and production process in this, for Slovenia extremely important industrial branch.
B.04 Guest lecture
COBISS.SI-ID: 2632187