In this work, epoxy composites filled with flake graphite of various size (less than 10 μm and less than 45 μm) were produced. The aim of the research was to develop a self-lubricating material with favorable tribological properties, i.e., reduced friction coefficient compared to unfilled epoxy resin and limited abrasive wear. The research material was produced using technical epoxy resins based on bisphenol A. The detailed process of composite production was described, and typical technological problems were considered. The addition of graphite led to an increase in dynamic viscosity, which positively limits the phenomenon of sedimentation, but an increase in the filler content also led to an increase in the porosity of the material. A series of tests have shown that the addition of graphite above 5% by weight allows for a reduction in the friction coefficient from 0.6 to 0.4 and significantly reduces the material’s tendency to abrasive wear.

The degradation process of thermal barrier coatings (TBCs) such as monolayered La₂Zr₂O₇, composite 50% La₂Zr₂O₇ + 50% 8YSZ, and double-ceramic layer (DCL) La₂Zr₂O₇/50% La₂Zr₂O₇ + 50% 8YSZ/8YSZ was investigated. Coatings were deposited using the atmospheric plasma spraying (APS) process (ceramic layer and bond-coat) on the Ni-based superalloy substrate with Ni-22Cr-10Al-1Y bond-coat. The thickness of the ceramic top-coats in all cases were 300 µm. In the case of La₂Zr₂O₇/8YSZ, the internal sublayer was built from 8YSZ powder whereas the outer from La₂Zr₂O₇. Between both sublayers’ “composite” a 50% La₂Zr₂O₇ + 50% 8YSZ zone was present. The “composite” 50% La₂Zr₂O₇ + 50% 8YSZ TBC system was sprayed from two different feedstock powders with equal weight ratios. In the first part of the investigation, the microstructural characterization of the TBCs was presented. The main goals were related to the characterization of the degradation processes in different TBC systems with special emphasis on the phenomenon in the thermally grown oxide (TGO) zone related to oxidation, and the phenomenon related to phase stability in ceramic top-coats as related to temperature influence. The oxidation test was carried out in air at 1100 °C for 500 h. In the second step of the investigation, the numerical simulation of the monolayered TBC 8YSZ and La₂Zr₂O₇ systems was analyzed from the stress distribution point of view. Additionally, the two-layered TBC coating of the DCL type was also analyzed.