Aircraft engines are a key focus of research and development. An example from BÖHLER Schmiedetechnik.
Highly stressed components
Speeds beyond the sound barrier, huge forces, and high temperatures: the extreme conditions inside jet engines demand much of their components, such as engine discs, posing a challenge for researchers and developers working in aerospace. Higher combustion temperatures in the drive unit are a means of raising aircraft efficiency, but this brings a linear increase in the thermal stress on components. Methods of counteracting this stress include modifying the titanium, nickel-based, and high temperature steel alloys.
Jet engines as the drivers of development
“New material developments are often initiated and driven forward by engine manufacturers,” says Gerhard Gerstmayr, Head of Sales at BÖHLER Schmiedetechnik, describing this development path. However, it’s a long path consisting of small steps. Quality controls and certifying new materials alone can take up to ten years. The primary technological challenge in the future will be to exploit a material to its full potential whilst adhering to strict manufacturer specifications.
Short development cycles to minimize costs
Martin Stockinger, Head of Business Development, Research & Innovation at BÖHLER Schmiedetechnik, outlines another key target area for making changes to the ‘engine’ value chain. The magic formula here is shorter development cycles, especially for the engine discs which are a critical component. Forging and heat treatments are simulated on parts geometry provided by the customer using the finite element method. The engine disc’s expected mechanical properties can then be modeled and made available to the customer in the form of a property profile.
"As a result, we are offering the customer a product with tailor-made mechanical properties. Clearly a unique selling point for BÖHLER Schmiedetechnik."
Factbox: Engine discs
- are key components in jet engines and gas turbines;
- form the mounting for turbine and compressor blades;
- rotate at many thousands of revolutions per minute – up to 1½-times faster than the speed of sound;
- must withstand high temperatures;
- are regarded as ‘critical components’, i.e. their failure would result in engine malfunction.