A method to obtain good high-temperature X-ray patterns with a Guinier–Lenné camera

Abstract

Good high‐temperature X‐ray patterns of metals or alloys can be obtained by reconstructing the camera support and positioning the camera in such a way that the plane of the sample is horizontal and above the X‐ray source. By choosing properly oriented mica sheets as a sample support, very sharp X‐ray powder patterns up to 1000°C can be obtained, which are practically free from parasitic lines due to the sample holder. This method does not require that the powder be glued to the support by refractory ceramics to prevent it from falling off at high temperatures. As an example, two phase transitions of the hydrogenated subcarbide Nb2CH0.3 between 20 and 1000°C are demonstrated.

X-ray diffraction

“…Two reviews on X-ray diffraction techniques at high temperature have appeared (293,359). Many descriptions of high-temperature attachments for powder diffractometers (80,92,185,190,360,403), including gas flame heating of the sample (267) as well as attachments for single-crystal or powder cámeras (23,26,36,166,332,342,365,371,375) have been published. Two unusual high-temperature techniques deserve mention.…”

An automated low-temperature Guinier X-ray diffractometer and camera

“…The structure refinement from the profile data is computed with an X-ray version of the Rietveld (1969) powder-refinement program modified by Young, Mackie &von Dreele (1977) with correction factors appropriate for the Guinier geometry (Oswald, 1980). Susz & Yvon (1973) and H~igg, Ersson, Rudenholm & Sellberg (1979) described high-temperature Guinier cameras. A first version of a low-temperature Guinier camera and diffractometer (Ihringer, Huber & Weiner, 1975) was used to get accurate cell parameters.…”