Institute of Physics of Materials AS CR, v. v. i. > Projects > Development of new joining methods for high entropy ceramics

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Development of new joining methods for high entropy ceramics

Anotace

The ultimate objective of the project is to develop a new, reliable, and reproducible technique for the joining of HEC to similar (HEC) and dissimilar materials (CMCs). The possibility of direct joining of selected representatives of high entropy borides ((Hf-Zr-Ti-Ta-Nb)B2, (Mo-Nb-Ta-V-W)B2) and high entropy carbides ((Hf-Zr-Ti-Ta-Nb)C, (Mo-Nb-Ta-V-W)C) will be investigated. At the same time, the utilization of refractory HEA (HfZrTiTaNb, MoNbTaVW) as the interlayers for the joining of HEC will be explored. At the end, the dissimilar joining of HEC to CMCs with the HEA interlayers will be investigated. This all will bring up new fundamental knowledge on the understanding of the effect of electric field and the substrate quality on the direct diffusion bonding of HEC, as well as the interfacial phenomena occurring at the HEC/HEA and HEA/CMCs interfaces. In addition, the operation limits of the joints will be identified. Such a study will provide comprehensive insights on the joining of HEC materials for aerospace applications. The following measurable specific objectives are defined (i) To prepare high entropy carbides and high entropy borides as substrate materials. (ii) To design and prepare high entropy alloys as interlayer materials. (iii) To identify the processing parameters and understand the mechanism of direct joining of HEC without any interlayer. (iv) To understand and clarify the effect of HEA interlayers on the joining of HEC. (v) To obtain a sound joint between HEC and Cf/SiC composites. (vi) To define the operational limits of the newly developed joints.