ПЕРСПЕКТИВЫ МЕТОДОВ ИНТЕНСИВНОГО СПЕКАНИЯ ПЬЕЗОКЕРАМИЧЕСКИХ МАТЕРИАЛОВ

Abstract

The paper investigates the possibility of changing the properties of piezoelectric ceramics for various purposes.The aim of the study is to correct properties by changing technological factors in the manufacture ofpiezoceramics without modifying their chemical composition. At the most important technological stage – sintering– the density, hardness and strength of piezoceramics are formed, which directly affect its electrophysicalparameters, since the piezoelectric effect is an Electromechanical transformation. Of particular interest are sinteringmethods that combine the process of compaction of particles with heating - hot pressing and spark plasmasintering. Such methods, due to the created uniaxial pressure, activate the diffusion processes of mass transferduring sintering, contributing to the production of high-density piezoceramics while lowering the sintering temperatures. However, unlike hot pressing, spark plasma sintering generates spark discharges between the powderparticles, which, in combination with ultra-fast heating (up to 1000 ° C/min), forms a fine-grained monophasestructure of ceramics. This microstructure increases the mechanical and electrophysical parameters of the resultingceramics. The aim of the study was to test the proposed sintering methods on piezoelectric materials of differentcompositions in order to control their properties. The objects of research were piezoceramic materials basedon the zirconate-titanate-lead system and their modifications, including multicomponent materials with high applicationpotential, as well as lead-free ferroelectric material Ba0.55Sr0.45TiO3 (BST). The dependences of theformed ceramic structure on the sintering method and temperature were determined using scanning electronmicroscopy. The regularities of "sintering method – microstructure – properties" are established. The effectivenessof hot pressing and spark plasma sintering methods for correcting the properties of piezoceramics of varioustypes of applications has been confirmed, which together with a decrease in sintering temperatures, as well as areduction in the duration of the process (by 36 times!) relevant for energy saving purposes.