Elastic Constants of Alumina and Silicone Nitride Measured by Using Synchrotron Radiation Source
Yasuo YOSHIOKA, Koichi AKITA and Hiroshi SUZUKI
Abstract:The x-ray elastic constants of sintered polycrystalline alumina and silicon nitride were measured for various hkl diffractions by using x-rays from synchrotron radaiation source (SR). The use of x-rays from the SR enables measurements to be taken at higher and constant Bragg angle 2q on many hkl diffractions and thus it is possible to measure the stress or the elastic constant with high accuracy. The measurements were carried out on seven hkl diffractions for alumina and four ones for silicon nitride. The results on the alumina were compared with the analytical values obtained from the elastic constants of a single crystal based on the Reuss and Voigt models. The measured values of E/(1+n) of alumina approximately agreed with the analytical values by the Reuss model and this means that the analytical value on any hkl diffraction can be used as the x-ray elastic constant. On the other hand, the experimental values of silicon nitride were slightly larger than the mechanical value, however, its maximum difference was within 7 %. Key Words:X-ray stress analysis, Elastic constant, Synchrotron radaiation source, alumina, silicon nitride, hkl diffraction, Reuss model, Voigt model.