Johannes Barthel

Johannes Barthel (1990)

Johannes Barthel (born November 24, 1931 in Chemnitz ; † December 17, 2015 in Dresden ) was a German materials scientist and solid-state physicist who had recognized achievements in the applied physics of pure substances, in single crystal growth , in the generation of dissipative structures, in the application of Tracer technology and the production of materials for superconductor research .

Life

From 1956 Johannes Barthel worked at the Institute for Applied Physics of Pure Substances in Dresden, founded by Ernst Rexer (1902–1983). In 1960 he received his doctorate as Dr. rer. nat. at the TH Dresden with new scientific findings on the zone melting process and with the experimental determination of material parameters for the extraction of heavy water . The doctorate to Dr. sc. nat. 1978 with a summary of all his findings on segregation and crystal growth determined his further scientific profile.

Scientific results

• the use of the technology of zone melting and the inclusion of chemical separation processes for the single crystal growth of high-purity, refractory metals
• the production of high-purity aluminum with the HF zone melting process and the levitation melting process
• the growth of single crystals of the highest purity z. B. single crystals of molybdenum, tungsten and niobium, iron with the electron beam zone melting process and the strain anneal method with comparatively highest purity.
• Participation in the cultivation of V3Si phases with a defined stoichiometric deviation. Like niobium monocrystals, these materials were used for fundamental research into superconductivity .
• Generation and use of dissipative structures for the production of finely dispersed heterostructures as a principle for the manufacture of new materials, especially on the basis of carbon and boron nitride .
• Creation of a complex picture of the segregation phenomena and their influence on the formation of dislocations .
• the determination of the effectiveness of zone melting as a cleaning and crystal growing method for the production of high-purity refractory metals with the inclusion of evaporation processes as well as the mathematical treatment and quantitative description of the impurity distribution taking into account the formation of a cellular solidification front.
• The interpretation and mathematical description of experimentally observed rotation or growth strips in crucible-free zone melting not only led to a deeper understanding of the relationship between crystal growth, impurities and their distribution, but also created the conditions for the creation of special defect structures in high-purity crystals.

In his scientific work, Barthel has proven to be the custodian and continuation of the work of Ernst Rexer and his concept of the unity of representation, structure and properties. As a co-designer and research group leader of complex display technologies, which include the methods of extraction, chlorination, separation from the gas phase, zone melt cleaning, single crystal growth and UHV annealing up to structural and physical characterization, he has the scientific profile initially of the Institute for Metal Physics and Pure Metals and later of Central Institute for Solid State Physics and Materials Research of the Academy of Sciences of the GDR .

From 1982 to 1990 Barthel was director of this central institute. Under his scientific direction, the research directions that are still viable today were established, expanded and profiled:

• Construction and cutting ceramics, the formation of a powerful research potential combined with modern plant technology,
• High temperature superconductor
• Rapid solidification and construction of the 2-roller technology

His focus was again on the unity of plant engineering, process development and research on the basis of well-founded material concepts for the production of new materials or materials with improved properties. It is largely thanks to this approach that this central institute was given a positive rating by the Science Council in the evaluation of the scientific institutions in the GDR :

“The Central Institute for Solid State Physics and Materials Research (ZFW) can be seen as an example of a“ successful generalist ”. In the field of materials science, it worked on a wide range of partly fundamental and partly application-oriented topics in various disciplines. In the evaluation, the institute expressly pursued the goal of maintaining this multidisciplinary working method (cf. WR 1992c: 103). In his case, the WR was convinced of the advantages of a broad spectrum of activities under one organizational roof (when some sub-groups were taken over by the FhG). He recommended that the ZFW be reorganized into an institute for solid-state and materials research, "whose specialty should be the interdisciplinary combination of basic solid-state research with application-oriented materials research" (ibid .: 105). "

Membership in scientific committees of the GDR

• Corresponding member of the AdW ;
• Member of the scientific advisory board for research into cosmic space;
• Chairman of the Scientific Council of the Complex Research Task Materials;
• Member of the scientific council for the main research area experimental methods in physics;
• Member of the working group for the basics of scientific device construction;
• Member of the National Committee for Crystallography ;
• Member of the standing expert commission for research technology.

After the end of his second appointment as director of the institute in 1990, he was employed as a research assistant at the institute at his own request. In 1992 this activity ended abruptly when the contract was canceled by the board of directors of the Institute for Solid State and Materials Research.

Johannes Barthel had been married for the first time since 1957 and had three children.

Publications

• J. Barthel: The zone melting process. In: Science and Progress. 12, 1962, p. 534
• J. Barthel, J. Kunze, R. Scharfenberg: About the impurity substructure in aluminum single crystals. In: Working conference on solid state physics in the physical society of the GDR and Hungary. 1963, Warnemünde
• J. Barthel, J. Kunze, R. Scharfenberg: Iron distribution and substructure in cellular grown aluminum single crystals. In: Phys. stat.sol. 6, 1964, p. 529
• K. Friedrich, J. Barthel, J. Kunze: About the influence of surface gases on the analytically determined gas content of molybdenum and tungsten monocrystals. In: J. Less-common Metals , 14, 1968, p. 55
• J. Barthel, E. Zedler, U. Wiesner: About the distribution of alloy partners in electron beam melted button samples. In: Zeitschrift für Metallkunde. 55, 1964, p. 29
• J. Barthel: About the zone melting of refractory metals. In: Annual General Meeting of the German Society for Metallurgy , Salzburg 1965
• H. Oppermann, G. Weise, J. Barthel, K.-H. Berthel: Molybdenum crystals with a very low residual resistance ratio. In: Physika sat. sol. 22, 1967, K 151
• J. Barthel, R. Scharfenberg: About the crystal growth of refractory metals during electron zone melting. ICCG 1966 Boston USA, In: crystal grow. , St. Peiser Editor / Bergamon Press 1967, p. 133
• J. Barthel, K. Eichler: About the influence of the layer-by-layer incorporation of foreign elements in zone melts on the effective distribution coefficient. In: Kristall und Technik 2, 1967, p. 55
• M. Zitnansky, J. Barthel: Evaporation coefficients of zirconium and hafnium in niobium and of iron, zirconium and hafnium in molybdenum. In: M. Balarin (Ed.): 3rd International Symposium on Pure Substances in Science and Technology, Dresden 1970 , 1972, p. 807
• J. Barthel: About the production of niobium of the highest purity. In: L. Kuchar (Ed.): 5. Spornik referatu 6. Sect , 1971
• M. Jurisch, J. Barthel: A mathematical treatment of the rotation stripes in the crystallization from the melt. In: Crystal and Technology. 2, 1967, p. 20

literature

• Werner Hartkopf: The Berlin Academy of Sciences. Its members and award winners 1700–1990 . Akademie-Verlag, Berlin 1992.
• Werner Hartkopf: The last yearbook of the GDR Academy. In: Meeting reports of the Leibnitz Societät. Vol. 9, 1995, p. 118.
• Herbert Hörz (Ed.): Research results from materials science: Otto Henkel on his 65th birthday. Akademie-Verlag, Berlin 1990.
• Jutta Morgenthal (Red.): Central Institute for Solid State Physics and Materials Research of the Academy of Sciences of the GDR: Research results from two decades. 1969-1989. Central Institute for Solid State Physics and Materials Research, Dresden 1989.
• Ernst Rexer : Pure substances in science and technology. Akademie-Verlag, Berlin 1963.
• Hans-Georg Wolf: Organizational fates in the German unification process: The development paths of the institutes of the Academy of Sciences of the GDR (= writings of the Max Planck Institute for Social Research, Cologne. Vol. 27). Campus, Frankfurt am Main 1996 ( PDF; 2.3 MB ).

Individual evidence

1. ^ Hans-Georg Wolf: Organizational fates in the German unification process: The development paths of the institutes of the Academy of Sciences of the GDR. In: Writings of the Max Planck Institute for Social Research, Cologne. Vol. 27. Campus Verlag, 1996, p. 173, mpifg.de (PDF; 2.3 MB)