SUPERPORE-X

SUPERPORE-X: Functionally graded porous Hastelloy-X nickel superalloy as a new class of materials for gas turbine seals applications

A. Bętkowska* ¹, M. Podsiadło ¹, A. Polkowska ¹, W. Polkowski¹

¹ Łukasiewicz Research Network – Krakow Institute of Technology, Zakopianska 73 Str, 30-418 Krakow, Poland

* E-mail: aleksandra.betkowska@kit.lukasiewicz.gov.pl

* Details of the projects: CLICK HERE

The Superpore-X project is focused on a development of new materials and technologies in the field of gas turbine seals application. The long-term vision of the project is to introduce new functionally graded porous Hastelloy-X (H-X) alloys having an improved performance and extended lifetime as compared to currently applied honeycomb seals. The main hypothesis behind the project is that the high temperature performance of new porous sealing materials based on H-X alloy might be significantly improved and tailored by a proper design of the manufacturing technology. In this regard, we propose a new powder- metallurgy based fabrication approach that offers a high flexibility in terms of controlling the size and distribution of pores (including a possibility for fabrication of porous functionally graded materials). Furthermore, the proposed method involves widely available, relatively cheap and non-toxic substances as porosity forming agents (“space holders”), what makes it both cost-effective and environmental friendly. Thus, the main scientific goal is to develop a process/structure/properties relationship for a fabrication of porous H-X alloys having controlled size and distribution of pores, through experimental studies on fundamental phenomena governing the formation of porous structure. In order to further increase efficiency of energy devices (e.g. gas turbine engines), both new materials that would be able to withstand thermomechanical loadings at increased working temperatures and new design concepts for an enhanced thermal/pressure management, are needed. The Project is formally organized into three Work Packages (WPs). The workflow merges a powder metallurgy processing, supported by ad- hoc structural characterization (WP1) with a validation of porous structures and performance properties (WP2); and a preparation of final proof of concept (WP3). In general, the WP1 is focused around a development of materials technology for a fabrication of porous H- X alloys. A specific research goal of this work package is to build up a fabrication procedure, by both a proper selection of batch materials (initial H-X powders and space holders) and tailoring the process parameters at its various stages. In turn, the WP2 is targeted towards an experimental validation of new materials and structures, in terms of their potential usefulness in sealing technologies. For this reason, various samples produced in WP1 will be carefully inspected, while key performance properties (namely, oxidation resistance, particle erosion and mechanical behavior), will be investigated in a comparative studies with bulk H-X and honeycombs (reference samples). Finally, exemplary components made of porous H-X having pre- defined (application oriented) size and distribution of pores will be produced and validated within WP3. In this project, a new type of seal structures made of functionally graded porous H-X alloys for potential usage in gas turbine engines will be designed, developed and examined. We expect that both materials properties and the fabrication process will be competitive to presently available honeycomb like structures. The accomplishment of research tasks will provide a number of new data on emerging group of functionally graded highly porous materials for structural applications. In particular, pioneering results on tailoring the functionality of new porous H-X alloys by knowledge- based adjusting a process window of the cost-effective and environmental friendly fabrication method (the space holder approach), will be provided. Furthermore, a whole set of key performance properties (oxidation resistance, abradability and high temperature strength) of the new seal materials, will be experimentally collected. We believe that the collaboration and gained experience during the work on the Project will allow to build an efficient fundament for future R&D actions involving more academic and industrial partners. The Project supports the personal development of young researchers (the PI), early career stage researchers, as well as Ph.D. students of the Industrial Doctorate Programme.