Contact
Intranet
SK
International
| JoinHEC – Vývoj nových metód spájania vysoko-entropických keramických materiálov | |
| Development of new joining methods for high entropy ceramics | |
| Program: | Bilateral – other |
| Project leader: | Ing. Tatarko Peter, PhD. |
| Annotation: | The main aim of the proposed project is to develop new joining techniques for high entropy ceramics (HEC) in order to improve the operational limits of the joints for aerospace applications. The project proposes an innovative way of manufacturing of HEC joints with potentially improved high temperature properties, using a direct solid-state diffusion bonding (without an interlayer) or diffusion bonding with refractory metal interlayers. For the first time, refractory high entropy alloys (HEA) will be used as the joining interlayers between a pair of HEC, or as the interlayer for joining of HEC to ceramic matrix composites (CMCs). The project aims to generate new fundamental knowledge on the understanding of the effect of electric field and surface preparation on the direct diffusion bonding of HEC, as well as the interfacial physico-chemical phenomena occurring at the HEC/HEA and HEA/CMCs interfaces. The mechanical performance of the joints at room and high temperatures will be investigated to define the operational limits of the joints. The project will provide a comprehensive insight on the joining of high entropy ceramics for potential aerospace applications. This may significantly expand the application potential of the recently developed next generation ultra-high temperature ceramics, i.e. high entropy ceramics. |
| Duration: | 1.7.2022 – 30.6.2025 |
National
| Keramické kompozitné materiály na báze SiC s vysokou tepelnou vodivosťou | |
| Silicon carbide ceramic composite materials with high thermal conductivity | |
| Program: | VEGA |
| Project leader: | Ing. Hanzel Ondrej, PhD. |
| Annotation: | The main goal of this project is preparation of dense silicon carbide (SiC) ceramics without sintering additives and/or silicon carbide composites with very low content (up to 1 wt. %) of sintering additives (oxides of rare-earth elements), with high thermal conductivity. The research will be focus on study of the effect of a-SiC and ß-SiC phase content on thermal conductivity of silicon carbide without sintering additives and the second research direction will be focus on study of the effect of amount and type of additives (oxides of rare-earth elements) on the thermal conductivity of SiC composites. In order to achieve project objectives, research focused on preparation of dense silicon carbide or SiC composite at relatively low sintering temperature (up to 2000°C) will be necessary. This process comprises study of SiC powders or SiC composite powders modification by freeze granulator, thermal annealing of granulated powders and followed by granules sintering with field assisted sintering technology (FAST). |
| Duration: | 1.1.2025 – 31.12.2028 |
| ComCer – Vývoj nových keramických materiálov komplexného zloženia pre extrémne aplikácie | |
| Development of new compositionally-complex ceramics for extreme applications | |
| Program: | SRDA |
| Project leader: | Ing. Tatarko Peter, PhD. |
| Annotation: | The main aim of the proposed project is to develop next generation ultra-high temperature ceramics capable of withstanding temperatures up to 3000°C for propulsion systems, rocket engines and other aerospace applications. This will be achieved by the synthesis of diboride ceramics with unique compositionally -complex structures, comprising of at least five metal elements. A systematic study will be conducted to generate new knowledge on the understanding of the effect of various molar ratios of individual metal cations in diboride structures on the stability, synthesis, sintering and mechanical properties of bulk diboride ceramics. The results will significantly contribute to the expansion of the high entropy ceramics concept with equimolar compositions towards the development of compositionally-complex ceramics with non-equimolar compositions. The project also proposes an innovative way of manufacturing ultra-high temperature ceramics, consisting of the development of ceramic composites based on the high-entropy and compositionally-complex diboride matrix, reinforced with the refractory additives. The output of the project will be new fundamental knowledge on the formation of disordered diboride structures, and their effect on mechanical properties of the materials at room, intermediate, and ultra-high temperatures. |
| Duration: | 1.7.2022 – 30.6.2026 |