Exploitable results High quality perovskite powders for high-tech applications of advanced ceramic technology The objective of the research was the preparation of different materials with high purity, fine and well defined particle size by the groups in Moscow and Minsk. The materials were checked for applications by the partners in Jülich, Twente and Steinfurt. The substances studied were: BaZrO3, SrTiO3, YBa2O3O7-x, Bi-Cuprate (2212, 2223), LaSr-nickelate, LaSr-cobaltite. The research was performed to obtain high temperature superconducting thin-film-components, precursor-material for superconducting levitation, gas-tight pellets for phase studies and new catalysts and sensor materials. One of the barriers on the way to thin film applications of the new group of HTSC's is the lack of development of target preparation technology. The method for the preparation of Hg-based superconducting ceramic target for thin film deposition was developed by optimisation of the precursor preparation technique, chemical composition and heat treatment condition during ampoule synthesis. The experiments for the preparation of thin films by laser ablation were performed to study the influence of deposition parameters on the composition and microstructure of the films. Substrates for thin film processing wre obtained using the Verneuil flame fusion method. Further improvement of the substrates' quality is seriously limited by insufficient quality of precursor powders. Modern methods of chemical homogenisation provided promising steps in solution of this problem. A new technique to control grain size of Verneuil precursor powders has been developed. The technique is based on the control of aggregate structure of the powder during its synthesis by means of combination the ultrasonic and thermal treatment. The effectiveness of this technique is demonstrated at freeze dried Fe3O3 and BaZrO3 powders. Finest powders of SrTiO3 were prepared by hydrothermal synthesis. The evaluation of their technological usefulness at the crystal growth facilities of Fachhochschule Münster lead to important conclusions about the role of different parameters of the precursor powders in the quality of the final crystal. The levitation force of Y-Ba-Cu-O-ceramic is enhanced by a special flakes precursor process. The obtained materials were studied for application of levitation devices. Another way to enhance the levitation force may be the controlled nucleation of decay products. Therefore studies of formation and decay of NdBa2Cu3Ox solid solutions during thermal treatment at different p(O2) were carried out. The next step is to apply these results for semi-finished products. Some effort was also put into estimating the lower boundaries of phase formation in the Bi-PbSr-Ca-Cu-O system as well as R'-R''-Ba-Cu-O system. Application of cryochemical homogenisation for precursor preparation gives a better understanding of the boundaries of the phase fields in this system. In this respect the synthetic skills of the Moscow group were complemented by the experience of the group from KFA Jülich in phase diagram studies. First samples of gas tight LaSr-nickelate were obtained by pressing and sintering. The investigation of their oxygen stoichiometry and its influence on electrophysical parameters lead to important data. Some of the newly discovered materials based on nickelate and cobaltite ceramics are promising for applications in catalysts and sensor materials. Searching for OpenAIRE data... There was an error trying to search data from OpenAIRE No results available
