X-ray measurement of stresses in a crystal grain by position sensitive detector
Suyama Yujiro; Ohya Shin-ichi; Yoshioka Yasuo
Abstract:Stresses in a single crystal specimen or any individual grain of polycrystal specimen were measured by the use of one dimensional position sensitive proportional counter (PSPC). A problem on such project is how to measure stresses experimentally because continuous Debye-Scherrer (DS) diffraction ring is only just a spot from a grain and appeared on an imaginary DS circle from polycrystal specimen. Therefore, it is important to convert from such a spot to measurable diffraction curve. We adopted a PSPC and a specimen oscillating mechanism in the present study. Large grained 3% silicone iron specimens were prepared and 211 diffractions on each grain under elastic loading were measured by Cr-Ka x-rays radiation after determination of orientation (n1n2n3) [w1w2w3] on each grain by Laue method. A specimen stage with the y and f rotating attachment was oscillated upon the x-ray irradiated point on the specimen surface in y and y + 90 degree directions by the use of two stepping motors. The oscillating areas were +- 3 degree in the y direction and +- 0.5 degree in the y + 90 degree direction, respectively and a measurable diffraction intensity curve from a DS spot was converted by this operation. Stresses under uniaxial loading were measured by this technique and we concluded that stresses in a grain can be measured without the use of lattice parameters on the non-stresses condition. Key Words:X-ray stress measurement, Single crystal, Position sensitive detector