New materials for gas turbines of the future

applications for power stations and airplanes have to meet increasingly high demands on system efficiency. The materials used must be absolutely safe and reliable under extreme thermal and mechanical loads. The BAM Federal Institute for Materials Research and Testing carries out research to achieve this objective.

Turbine blades made from titanium aluminides

BAM's investigations now cover turbine blade materials made from an intermetallic titanium aluminide alloy (TiAl). Such alloys have very high tensile strength and a reasonable toughness at high temperatures, light weight, extraordinary corrosion resistance, and the ability to withstand extreme temperatures. Previously, turbine blades were made from nickel alloys with a relatively high specific weight. Aeroplane engines have to maintain their full strength at very high operating temperatures and TiAl alloys materials fulfil this requirement.

BAM is investigating the material properties of new TiAl turbine blade alloys in a research project sponsored by the German Research Foundation (DFG). The materials are exposed to a combination of thermal load and mechanical load. The material behaviour must be characterized under complex loads so that the design engineers can develope components using computer models. The objective of the project is to enable engines to use titanium alloy TiAl turbine blades safely and reliably in practice.

Coating of turbine materials for power stations

Electric power stations equipped with gas turbines are operated at high gas temperatures. Heavy-duty turbine blades are cooled from the inside and are coated with a thermal protection system on the outside.

Supported by the DFG, BAM examines and develops alumina coatings for oxidation and hot corrosion protection of nickel-based alloys. The objective is to develop efficient coating processes in order to supplement existing thermal protection systems or open up new applications.

BAM will present the results at MSE Materials Science and Engineering Congress and Exhibition, which will take place in Nuremberg between 1 and 4 September 2008 (www.mse-congress.de).

Contact: Turbine blades from titanium aluminide
Dr.-Ing. Birgit Skrotzki
BAM Division V.2 Mechanical Behaviour of Materials
Phone: +49 30 8104-1520, email: birgit.skrotzki@bam.de
Coating of turbine materials for power stations
Dr. sc. nat. Marianne Nofz
BAM Division V.4 Advanced Ceramics
Phone: +49 30 6392-5921, email: marianne.nofz@bam.de