Ten selected publications
- J. Gröbner, A. Kozlov, R. Schmid-Fetzer, M. A. Easton, S. Zhu, M. A. Gibson, J.-F. Nie, “Thermodynamic analysis of as-cast and heat treated microstructures of Mg-Ce-Nd alloys”, Acta Materialia, 59, 613-622 (2011).
The elucidation of metastable phase formation and the subsequent transformation from the as-cast to the heat treated state is a particular strength of the thermodynamic approach and, thus, a powerful tool for alloy development.
- A. Kozlov, M. Ohno, T. Abu Leil, N. Hort, K.U. Kainer, R. Schmid-Fetzer, “Phase Equilibria, Thermodynamics and Solidification Microstructures of Mg-Sn-Ca Alloys - Part 2. Prediction of phase formation in Mg-rich Mg-Sn-Ca cast alloys”, Intermetallics, 16, 316-321 (2008)
Predictions of as-cast phase formation and solidification behavior in ternary Mg alloys are made by thermodynamic calculations and validated experimentally. The predictions are based on detailed thermodynamic investigations of Mg-Sn-Ca phase equilibria.
- R. Schmid-Fetzer, D. Andersson, P. Y. Chevalier, L. Eleno, O. Fabrichnaya, U.R. Kattner, B. Sundman, C. Wang, A. Watson, L. Zabdyr, M. Zinkevich: "Assessment techniques, database design and software facilities for thermodynamics and diffusion", Calphad, 31, 38-52 (2007)
The success of the Calphad technique depends upon the reliability of thermodynamic databases. Good practice is detailed for the assessment process in generating databases with the necessity of stringent quality assurance.
- M. Ohno, A. Kozlov, R. Arroyave, Z.K. Liu, and R. Schmid-Fetzer, “Thermodynamic modeling of the Ca-Sn system based on finite temperature quantities from first-principles and experiment”, Acta Materialia, 54, 4939-4951 (2006).
It is shown that the combination of finite temperature first-principle calculations and the tool of Calphad modeling provides a sound basis to identify and judge on conflicting key thermodynamic data in the Ca-Sn system.
- M. Ohno, D. Mirkovic and R. Schmid-Fetzer, “Liquidus and Solidus Temperatures of Mg-rich Mg-Al-Mn-Zn Alloys”, Acta Materialia, 54, 3883–3891 (2006)
It is shown that and why the widely accepted liquidus and solidus temperatures for important Mg-alloys, detected by thermal analysis, are not actual liquidus and solidus. Solidification proceeds under non-equilibrium conditions even at extremely low solidification rates of 1 K/min.
- J. Gröbner, D. Mirkovic, R. Schmid-Fetzer: Thermodynamic aspects of grain refinement of Al-Si alloys using Ti and B. Materials Science and Engineering A, 395, 10-21 (2005)
A consistent thermodynamic description of quaternary Al-Si-Ti-B alloys is generated and applied to elucidate the mechanisms of phase formation and thermodynamic driving forces in grain refining Al- and Al-Si alloys using titanium and boron.
- J. Gröbner, D. Mirkovic and R. Schmid-Fetzer: Monotectic four-phase reaction in Al-Bi-Zn alloys. Acta Materialia, 53, 3271-3280 (2005)
Solidification produces interesting new microstructure with finely dispersed phase L’’ precipitating jointly with the two solid phases during the invariant monotectic four-phase reaction, L’ = L’’ + (Al)' + (Zn), predicted by thermodynamic calculations and confirmed experimentally.
- Y. Austin Chang, Shuanglin Chen, Fan Zhang, Xinyan Yan, Fanyou Xie , Rainer Schmid-Fetzer, W. Alan Oates, “Phase Diagram Calculation: Past, Present and Future”, Progress in Materials Science, 49 (2004) 313-345
Highlighting the great success of the Calphad route in obtaining multicomponent phase diagrams for technological applications, notable shortcomings have been noted. The results obtained to-date using a second generation of software open up new avenues for automatic calculation of more reliable multicomponent phase diagrams for technological applications.
- B. Onderka, J. Unland, R. Schmid-Fetzer, “Thermodynamics and Phase Stability in the In-N System”, Journal of Materials Research 17, 3065-3083 (2002)
Widely reproduced data in the literature are shown to fabricate thermodynamically impossible negative absolute entropy of InN. Complete P-T-x phase diagrams are given, strongly suggesting solid InN to be metastable under ambient conditions. Nitrogen fugacity is quantitatively assessed and CVD grown films of InN are used for validation.
- R. Schmid-Fetzer, J. Gröbner, “Focused Development of Magnesium Alloys using the Calphad Approach”, Advanced Engineering Materals 3, 947-961 (2001)
Alloy compositions with promising possibilities for microstructure design can be selected by means of thermodynamic calculations. Following that guideline helps to avoid large scale experiments with less promising alloys. This method is a powerful tool to cut down on cost and time during development of Mg-alloys.