Portable simultaneous XRF/XRD device for an in-line phase monitoring of ferroelectric's production

摘要

To control the structure of piezoceramics in the course of their manufacture, portable x-ray complex developed based on polycapillary optics was used. Polycapillary optics permits to render the instrument significantly smaller in size, use low-power x-ray source (-30W), improve resolution, and decrease the exposure time. Formation by Kumakhov half-lens of the primary parallel x-ray beam and filtration of diffracted radiation by a special polycapillary system enables successful express analysis of the structure in the production environment. Analysis was performed of completeness of the Pb_3TixZryO_3 phase formation in case of low-temperature (synthesis) and high-temperature baking of the mixture of components, presence of free PI>, observance of specified ratio of zirconium content to titanium. Ferroelectrics feature maximum piezoelectric properties only within a narrow range of phase and element composition (x 48±2, y 52±2). This interval is correspondent to pseudo-cube lattice with a = b « c crystalline cell parameters. A correlation between electrophysical and structural parameters of piezoceramic elements has been established. Presence of tetragonal and rhombohedronal splittings depending on technological factors (phase composition of raw material, its dispersion, temperature and time of baking) has been shown.