Flame Technique for High Temperature Single Crystal Weissenberg Photography (1000–3000°C)

Abstract

Oxy-acetylene flame heating has been employed with an ordinary Nonius Weissenberg camera for high-temperature single-crystal studies over the the range 1000–3000°C. The regulator blow pipe is mounted horizontally on the camera track and one end of the experimental crystal (1 cm long) is heated by the vertical flame issuing out of a 0,5 mm bore nozzle. A long slot cut at the top of the film-cassette allows the flame to escape out without touching the X-ray film. The film-cassette consists of two split-halves hinged on one side so that it can be opened and slipped over the screen tubes. This arrangement avoids the necessity for removing the flame each time a new film is mounted on the camera. The goniometer arcs can be positioned during high-temperature exposures, and there is no need to water-cool the cassette up to the highest temperature. The device has been used to take photographs of MgO single crystals at 2100°C. It permits a ready application to diffractometers based on Weissenberg geometry.