Winner of the Customer Survey Raffle Prize: Dr. Dirk Ponge
Participants in the customer survey had the chance to win a €250 prize in a raffle. This year the winner was Dr. Dirk Ponge, Group Leader at Max-Planck-Institut in Düsseldorf, Germany. Read below about his work with Thermo-Calc products.
I am the group leader of the group ‘Mechanism-based Alloy Design’. The group works on the microstructure-oriented design of high-performance steels, engineering Al-, Ni- and Ti-alloys. Projects focus on strain hardening mechanisms such as the interplay of dislocations, twins and deformation driven phase transformations. Of special interest are confined phase transformation phenomena at grain boundaries and dislocations. Especially for materials with high strength, hydrogen embrittlement provides a challenge. Here the damage and failure mechanisms are analyzed in order to develop novel high strength materials with low susceptibility against hydrogen embrittlement. In order to improve the sustainability of materials, we design alloys that can tolerate the highest possible scrap and thus impurity fractions.
For alloy design, not only the alloy composition is decisive, but also the corresponding thermomechanical treatment. This enables us to create tailored microstructures to improve combinations of mechanical properties like strength, ductility and toughness. We use Thermo-Calc to design new alloy compositions. This helps to prevent solidification problems and design heat treatments. In medium manganese steels, for example, we use thermodynamic calculations to predict composition and stacking fault energy of reverted austenite formed at a specific intercritical annealing temperature. Kinetic simulations by DICTRA helps to plan the heat treatment time. We further develop multi-step heat treatments based on DICTRA simulations to produce very special multiphase microstructures with ferrite, metastable austenite (for high ductility) and stable austenite (increase security against hydrogen embrittlement).