In the 1960's, with the development and application of nuclear power for the generation of energy and the associated programs to develop nuclear fusion technology in Germany and abroad, demand was growing to build up expertise in the phenomenon of radiation damage in materials. In this regard Heinrich Wollenberger decided to accept the position of responsible scientist for the van-de-Graaff laboratory in Aachen, belonging to the IFF of the KFA (now FZ Jülich), where he formed an internationally renowned group for basic research on point defects in metals in a short time. Vacancies and self-interstitials in metals were investigated not only through conventional resistivity measurements but also by using low-temperature calorimetry and dilatometry for the measurement of fundamental parameters of such defects. For his pioneering work he received the “Tamman-Gedenkmünze” of the DGM in 1973. Several articles by him were published in handbooks, including the chapter “Point Defects” in Physical Metallurgy, edited by R. W. Cahn and P. Haasen.
In 1975, Heinrich Wollenberger accepted positions as professor at the university department “Werkstoffwissenschaften” of the Technische Universität Berlin, Germany (TUB), and simultaneously as Head of the Department of Engineering Materials at the Hahn-Meitner-Institute (now Helmholtz Zentrum Berlin für Materialien und Energie GmbH). He became interested in engineering alloys including high-temperature superalloys with prime focus on phase stability. For this purpose, he established several complementary analyzing techniques and built up modelling expertise in his group. Beside the analytical and high resolutiontransmission electron microscopy (TEM) he set up a small-angle neutron scattering (SANS) beam line at the research reactor BER II, introduced the method of secondary-ion mass spectrometry (SIMS) for diffusion measurements and established a field ion microscope (FIM). He always cooperated closely with colleagues of the Bundesanstalt für Materialforschung und -prüfung (BAM) and the TUB. Thanks to his initiative one of the first tomographic atom probe (TAP) instruments in Germany was installed and operated at HMI. Prof. Wollenberger was one of the driving forces to establish the Sonderforschungsbereich 339 “Schaufeln und Scheiben in Gasturbinen – Werkstoff und Bauteilverhalten” in Berlin. Additionally to his numerous engagements in Germany, he cultivated international collaborations in India, France, China, Japan, USA, Ukraine, Russia, England, Argentina and Switzerland.
When he retired in 1998 from his duties as the Head of a Department of more than 20 senior scientists and PhD students, he continued to maintain contacts with the scientific world and colleagues worldwide. He kept contributing scientifically. This included his work as an associate editor of Journal of Materials Research.
Heinrich Wollenberger always encouraged new scientific developments that went beyond his own field of work. As a university professor he recognized and encouraged the talent of the students in their various steps of scientific carrier. Even when he was already retired he keenly followed new developments.
With the demise of Prof. Heinrich Wollenberger we have lost a leading figure in the field of material science. He will always be remembered as an internationally renowned researcher, a convinced academic teacher, and a good friend.
Staff from the Hahn-Meitner Institute (now HZB)