Interrogation of German Scientists Regarding Quartz Crystals and other Piezoelectric Materials FIAT 641
Office of the Military Government for Germany (US)
Office of the Director of Intelligence
17 December 1945
Prepared by Allen C. Swinnerton Major, Sig C Army Branch, FIAT (US)
Keywords: Günther; Spangenberg; Haase; Gerber (Zeiss); Nacken; Bechmann (Telefunken); University of Göttingen
It was evident at the close of the war that Germany had embarked upon an extensive program of Ersatz materials for quartz crystals. The program consisted of (1) a search for a method of synthesis of quartz and (2) an exploration of a variety of substances which might be grown artificially and have favourable piezoelectric properties.
Interrogation of P.L. Günther - Heidenheim 29 and 30 November 1945
1. At the request of the Luftwaffe in June or July 1944, Günther began experiments on the production of artificial quartz crystals by the reaction of SiCl with various oxides. This work was begun at Breslau (Technische Hochschule)) and in March 1945 he moved to Leuchstaffe G.m.b.H.? at Steinach in Thuringia. The work on production of quartz by the reaction method was not successful enough to continue, and Günther was shifted to work on detector crystals. He worked on Silicon and pyrite. His assistent Chytrek was given charge of actual production of quartz by the Nacken method. This progressed only three or four weeks until the end of the war. ...... The general technique can be described as a high temperature vapor reaction. Two specific methods were tried with the materials sealed in quartz glass tubes
Interrogation of Kurt Spangenberg-Heidenheim 29 November 1945
Spangenberg and his laboratory were moved from Breslau to Jena about January 1945. THis was a serious interruption to his investigations. For many years he had been growing crystals and prepared to work from melts, citing the example of NaCl in which large cylindrical crystals could be drawn out of a crucible after a seed had been inserted on a rod. However, it was obviously impossible to treat SiO2 that way because of the inversion point. The same was true of the substances he was called to investigate. .......... Seeds were secured in general by placing 4'' x 10'' evaporating dishes in CaCl2 dessicators. Spangenberg believes spontaneous crystallization, or innoculation, of a super saturated solution would give better seeds. The seeds which were used were always unclear, and the resulting new crystals always had flaws. ....... Hairs are used to suspend the seeds. The seeds are drilled, and the hair passess through the hole. A wire instead of hair, would cause fracturing of the edges of the hole; cause cracks to start in the seed, and equally important, cause granules or splinters which would serve as secundary nuclei.
Interrogation of Max Haase - Heidenheim 30 November 1945
Haase's work was done at Zeiss, Jena, and he worked with Joos and gerber on Na Br O4, phosphates, and arsenates. Work was begun intensively only in July 1944. .... Seeds were drilled with 2 holes and wired on to the underside of a special steel plate (steel V2 A) which in turn was rotated in the vessel containing the solution.
Interrogation of E. Gerber - Heidenheim 30 November 1945
Gerber was associated with Joos and Haase in the crystal work at Zeiss, Jena. His job was the technical physicist function of determining properties, - piezoelectric and elastic moduli, etc, and to select angles for cutting and the like. .................... Gerber gave the following figures with some degree of assurance: At 776 kHz the R of quartz = 300 ohms, R Bromate) = 300 - 400, R (NH4 H2 PO4) = 50 ..... In response to questions regarding the Zeiss technique of thin-quartz-plate grinding, Gerber stated that quite a large number of plates of 49° cut had been produced at 60 MHz by very careful handwork vy very skillful workmen. The laboratory made a very few at 100 MHz, but the reported 200 MHz was projected research only. .. Tourmaline crystals were made as high as 400 MHz by skillful handwork. These were 7 mu thick. No synthetic tourmaline was attemped. .. The angles cut found to be best for both the phosphate and the bromate were at 45° to the axes. ......... According to Gerber most of the German crystals were used in parallel resonance with Pierce type circuits. Series resonance applications were not used, and there was only a limited use of Miller circuits According series resonance circuits Gerber apparently was wrong, as the Heegner oscillator was used by Telefunken. (AOB)
Interrogation of Richard Nacken - Schramberg, 5 and 6 December 1945
As a professor at the University of Frankfurt am Main, and as director of the Mineralische and Petrografisches Institut of the University, he had for many years carried on researches on rocks and minerals and their artificial production. He was supported in his research wok by state funds. He planned to organize a Hydro-Therminal Institute for the study of mica, asbestos, quartz and other hydro-therminal minerals. .. In 1936 he advised Dr. Rukop of Telefunken that quartz could be made artificially and suggested that the natural quartz supply would not meet large demands. After was began in 1939, he informed the government agents at Idar-Oberstein - the export-import centre of gem ,aterials including quartz - that the supply of natural quartz would not be sufficient. However, no attention was paid to his suggestions. .. At the end of 1943 and beginning of 1944 the government became panicky and wanted him to produce quartz in quantity overnight. His laboratority was moved from Frankfurt am Main to Schramberg, and he was given ample space in the Nunghans Watch Factory (should most likely be: Junghans, AOB). By late 1944 he had established the conditions under which quartz would deposit rapidly yet clearly from solution on a seedplate of natural quartz. The method was reported to the government and that was the last he knew of the matter, except that Telefunken made patent applications on his method and ordered equipment, but never actually started manufacture. He denied all knowledge of the plant at Steinbach in Thuringia (Thüringen, AOB). .......
Interrogation of Rudolf Bechmann (Telefunken), Berlin 9 December 1945 (Joint with Mr. J.L. Greighton, G.P.O.)
Bechmann was in charge of development and production of quartz crystal units for Telefunken. In 1942 he was made Ringleiter für Quartz in the Speer Ministry and as such responsible for the whole quartz Industry. ... December 1944 production .... Before the war the annual production was of the order of 10,000. In 1942 it had reached 230,000; in 1943 350,000; and in 1944 approximately 400,000 .... The general, methods of fabrication differed from those commonly used in the United States in the following respects: Use of circular crystals involved the rounding operation between "dicing" and lapping. .. Orientation by optical and mechanical means rather than by X-ray. (Only one plant used X-rays goniometers) ... .... Introduction of the wide-spread use of silver plating for practically all crystals. .... .... The organization and control of the industry was quite loose, particularly before 1943 ...
Interrogation at Mineralogisches und Petrographisches Institut, University of Göttingen, 12 and 13 December 1945
Dr. Carl Correns worked on the problem of producing quartz crystals from melt. In order to secure a temperature sufficient below 575° C to avoid a quartz, he selected .... Dr. Helmut G.F. Winkler was returned from the army at Corrent's request to investigate the possibilities of producing nepheline crystals ..... Dr. Walcher of the Physikalisches Institut was contacted to learn the location of Dr. Spitzer who, ...
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