NiAl-Gefügeverstärkung durch metallische Fasern/Lamellen mittels gerichteter Erstarrung
Final Report Abstract
The research objective of the project is to develop a new generation of NiAl composites reinforced by refractory metallic fibres or lamellae. The composites, which have a eutectic composition (NiAl-9Mo, NiAl-34Cr and NiAl-28Cr-6Mo), will be produced by means of specially controlled directional solidification so that the refractory metallic fibres/ lamellae will be generated and aligned in-situ in the NiAl matrix along the solidification direction through the eutectic reaction. It is expected that such quasi-single crystalline NiAl composites will possess remarkably improved fracture toughness at room temperature and an increased yield strength as well as superior creep resistance at high temperatures above 1100 °C. Such NiAl composites will be used for structural applications at high temperatures, for example as rotor blade material for modern gas turbine machines with operating temperatures of 1100 °C to 1300 °C, to reach a total thermal efficiency of η ≥ 65%. In the course of the investigation, a technical data bank will be developed based on the results which includes the optimization of the process parameters for directional solidification, microstructures as well as the thermomechanical properties of the investigated materials at RT and at high temperatures. This technical data bank is designed to transfer the investigation’s results to future industrial production.
