Seznam abstraktů 2015: KOMERČNÍ PREZENTACE

Computational thermodynamics, such as the CALPHAD (CALculation of PHAse Diagrams) method, has evolved over the past four decades to become a powerful, flexible tool for the study of a variety of scientific and technological areas of industrial importance. For example, it was rather early on successfully applied in alloy development for steels, and has since then continuously developed towards use in more and more applications within the lifecycle of steels. Computational kinetics software tools, such as DICTRA which simulates diffusion controlled reactions based on numerical solution of the multi-component diffusion equations, and TC-PRISMA which treats concurrent nucleation, growth/dissolution and coarsening using Langer-Schwartz theory and the Kampmann-Wagner numerical approach, are today also successfully applied within several areas of the lifecycle of steels.

This presentation aims to describe some recent advances in the application of computational thermodynamics and kinetics to complex situations within the lifecycle of steels, ranging from alloy design to scrap re-cycling. For example, applications in the R&D stage can be found in pre-screening potential candidate compositions to guide experiments more efficiently, and in optimizing the operational conditions, etc. Applications can also be found in predicting phase formation and determining the sensitivity of a particular property for quality control; simulating the nucleation and growth of precipitates during heat treatment; predicting liquidus temperature from mixing scrap metal of different compositions and predicting reactions during combustion of waste for the application of waste and re-cycling. In the present work, selective application examples in casting, forging/rolling, heat treatment, joining/welding, corrosion and failure analysis will be demonstrated.

Investigation of new materials and processes usually starts at laboratory scaled stage. Relatively small samples are model processed on different equipment. If resulted material properties are favourable, it is very useful to realize the next stage of the research – a prototype production. Parameters achieved on laboratory scale should be attainable on larger semiproducts. Possibilities to transfer proper technological conditions from small samples to real size prototypes are represented by the procedure using the synergy of both physical and numerical modelling.
Laboratory samples are processed on physical simulators, which load the material of sample by specified deformation and thermal process which had been previously determined by numerical simulation an industrial process. The thermomechanical process should be modified until the material reaches optimal parameters. Another numerical simulation of the industrial process follows, where boundary conditions are adapted to achieve optimized deformation and thermal loading on large semiproducts.
Prototype production regarding forming is performed on hydraulic presses, reversible rolling machine, swaging machine and extrusion equipment in COMTES FHT centre. In the field of heat treatment different furnaces with and without protection atmosphere are available, as well as induction heat treatment facility. Experimental material itself could be casted In vacuum induction melting furnace, which makes it possible check chemical composition and alloying elements during melting.