Papers by Author: Marek Kostecki

Abstract: The paper is concerned with the thermal properties of cathodic ceramic targets built on the basis of zirconium oxide modified with rare earth metal oxides such as La2O3, Nd2O3, and Gd2O3. The experiments also included the production of the TZ-3Y, TZ-3Y+20mol% coatings (La2O3, Gd2O3) using the EB-PVD method, and characterization of these coatings. Within the temperature range examined (20 to 120oC), the targets that contained rare earth metal oxides appeared to have lower thermal conductivity λ (2.07-1.22 Wm-1K-1) than the TZ-3Y target (3.6-3.05 Wm-1K-1). The present study was a continuation of our earlier experiments devoted to the examinations of zirconium oxide ceramic targets intended for producing refractory, heat-resistant nanocrystalline coatings.

Abstract: Technology of thermal ceramic barriers (TBC) has been chiefly designed for materials with a single thermal barrier of the 7YSZ type. A high content of Y2O3 ensures a good phase stability of the YSZ material. In search for other alternative materials suitable for TBC, the material most often examined is modified zirconium oxide. The modification consists of stabilizing the ZrO2 powder with Y2O3 and doping it with La, Gd and Nd. This paper presents the results of studies on producing cathodic zirconium oxide-based ceramic targets intended for depositing refractory heat-resistant nano-crystalline TBC coatings. The targets are characterized by a high density (close to its theoretical value) and have a homogeneous phase and chemical structure.

Abstract: Paper presents a novel application of magnetostrictive delay lines, which give a possibility of real time monitoring of strain in ceramic components. Magnetostrictive delay line was based on highly magnetostrictive Fe-Si-B amorphous alloy ribbon, mounted outside of ceramic component, what is a new solution for increasing sensor’s sensitivity. Developed specially for this sensor, hybrid digital-analog signal processing unit covers the sample-and-hold integrated circuit. The achived sensitivity and repeatability of the sensor confirms, that such solution is suitable for ceramic machine tool monitoring.