As customer demand grows for the highest performing and most fuel-efficient power solutions, the demands on those materials used for engine components also grows. Materials used within the hot gas path of the engine are generally operating at the very limits of their capability, and the processes employed to ‘join’ these next generation materials must guarantee joints that are at the very highest level of strength and durability.
The application of next generation material combinations in more efficient designs therefore requires the exploitation of highly advanced joining technologies. Increasingly these technologies are deployed against those material combinations which are conventionally considered to be ‘un-weldable’.
One key example of an advanced joining process developed and in use by Rolls-Royce is Solid-State Friction Welding, in which the two parts are rubbed together under very high linear or rotational loads, and forged into a single fused component. Development of these processes is allowing more efficient designs of engines to be realised, employing those high temperature super alloy materials grades that are required on today’s modern engines (which would previously have been bolted together with a weight and performance penalty).
In order to achieve even greater consistency in welding performance, Rolls-Royce is taking advantage of computer modelling of the welding operation, allowing potential distortion of the component or unwanted stresses to be forecast.
Automation technology can offer some significant benefits in cycle time, productivity and consistency, with Rolls-Royce employing state-of-the-art vision systems, robots and other feedback systems for application to a number of previously manual joining and welding processes.
Advanced joining technology