Analysis of the development of microscopic residual stresses on quartz particles in porcelain tile

This paper examines the development of microscopic residual stresses on quartz particles in porcelain tile using the XRD technique. The study was conducted with a typical porcelain tile composition consisting of sodium feldspar, kaolin, and quartz, using quartzes with different particle sizes. The methodology used, based on determining the volume strain of the quartz unit cell, allowed a residual stress value equivalent to the entire particle and not just to a given crystalline plane to be obtained. The linear thermal expansion measurements indicated that, for all test compositions, the quartz in the mixture contributes to a thermal expansion coefficient comparable to the expansion of its c-lattice parameter. When this information was taken into account in the theoretical estimation of microscopic residual stress, the results were verified to be consistent with the experimental measurements.