User:Reinerkirchheim
Reiner Kirchheim (born 24 May 1943 in Halle/Saale, Germany) is a German physicist and material scientist. He is a retired professor of the Georg-August-University of Göttingen and a member of the Max-Planck Society (external member of the Max-Planck-Institute in Düsseldorf).
Kirchheim was elected a member of the National Academy of Engineering in 2017 for contributions to thermodynamics and kinetics of hydrogen behavior in metals and solute/defect interactions in other materials.
Biography
[edit]Reiner Kirchheim received his degree in physics (1971) and his doctoral degree (1973) from the University of Stuttgart. From 1973 till 1993 he worked as a group leader at the Max-Plank-Institute in Stuttgart interrupted by extended visits as guest professor at the Rice University in Houston (1979-1980), the University of Illinois at Urbana-Champaign (1983), the Ohio State University in Colombus (1992) and at NIST in Gaithersburg (1998). In 1988 he made his habilitation at the University of Stuttgart and in 1993 he took the chair for metal physics at the Georg-August-University of Göttingen. After retirement (2008) he became a distinguished professor of the state of Lower Saxony.
Research
[edit]Reiner Kirchheim has contributed by experiment and by modelling to the area of thermodynamics and kinetics of crystalline and disordered materials including glassy metals, polymers and oxides[1]. By applying Fermi-Dirac Statistics and random walk theory he was able to describe the solution and transport behavior in defected materials[2]. In this context the interaction between solute atoms and crystalline defects like dislocations and grain boundary could be described by a site energy spectrum in analogy to electrons in solids by a spectrum of energy levels. Contrary to the segregation to and trapping by defects, which affect the solubility and diffusivity, the formation energy of the defects themselves is reduced by solute segregation. This is known for surfaces energies by the Gibbs Adsorption Isotherm, which has been extended by Reiner Kirchheim to include the formation energy of all kinds of discontinuities of structure i.e. surfaces, defects in crystals, inhomogeneities in amorphous matrices etc. as long as an excess of solute at the discontinuities exists[3]. Thus the term surfactants was replaced by defactants (defect acting agents)[4]. Because defects like vacancies, dislocations or stacking faults determine plastic deformation of materials, their formation energy is often dramatically changed in the presence of solute atoms. An example is hydrogen embrittlement of steels[5].
Reiner Kirchheim also provided a deeper insight into the passivity and electropolishing of metal[6,7]. By using the Tomographic Atom Probe he studied the nucleation of new phases in alloys and the interdiffusion of thin films[8].
Awards and honors
[edit]· 1987 Scripta metallurgica outstanding paper award
· 1990 Carl Wagner Prize
· 1998 Elected Member of the Academy of Science Göttingen
· 2002 Elected Member of the Academy of Science and Technology (acatech), Germany
· 1980-2000 Highly Cited Author in Materials Science
· 2003 Honda Memorial Award, Tohoku-University, Sendai
· 2004 Heyn-Denkmünze (highest award of the German Materials Society, DGM)
· 2005 International Award of Materials Engineering for Recourses, Akita, Japan
· 2007 Lee Hsun Lecture Award, IMR Shenyang, Chinese Academy of Sciences
· 2008 Distinguished Professor of the state Lower Saxonia
· 2008 Reinhart-Koselleck-Project of the DFG
· 2010 Member of the Max-Planck-Society and External Member of the Max-Planck-Institute for Iron Research GmbH, Düsseldorf
· 2011 Honorary Member of the German Materials Society, DGM
· 2011-2022 Member of the Advisory Board and Principle Investigator of the World Premier Institute I2CNER in Fukuoka, Japan
· 2017 Elected Member of the National Academy of Engineering , Washington, DC
References
[edit]1. R. Kirchheim, Solid solutions of hydrogen in complex materials, In Solid State Physics, eds. H. Ehrenreich and F. Spaepen, Elsevier, Amsterdam (2004), Vol. 59, 203-305
2. R. Kirchheim and U. Stolz, Modelling tracer diffusion and mobility of interstitials in disordered systems, J. Non-Cryst. Solids 70 (1985) 323
3. R. Kirchheim, Reducing grain boundary, dislocation line and vacancy formation energies by solute segregation. Acta Materialia 55 (2007) 5129-5148
4. R. Kirchheim, On the solute-defect interaction in the framework of a defactant concept , Int. J. of Materials Research 100 (2009) 483-487
5. R. Kirchheim, Revisiting hydrogen embrittlement models and hydrogen induced homogeneous nucleation of dislocations, Scripta Mater. 62 (2010) 67-70
6. R. Kirchheim et al., Corros. Sci. 29 (1989) 899 and 183
7. R. Kirchheim et al., J. Electrochem. Soc. 128 (1981) 1027
8. T. Al-Kassab, H. Wollenberger, G. Schmitz and R. Kirchheim, Tomography by Atom Probe Field Ion Microscopy in "High-Resolution Imaging and Spectroscopy of Materials", F. Ernst and M. Rühle eds., Springer Verlag (2002) 271-320
Links
[edit]https://www.uni-goettingen.de/de/557287.html
https://adw-goe.de/mitglieder/personendetails/person/reiner-kirchheim/
https://en.acatech.de/person/reiner-kirchheim-12395/