The general availability of a new technology is one thing; its transfer into the highly-regulated world of commercial aircraft operation and MRO is an entirely different matter. Lufthansa Technik established the AM center at the beginning of 2018. Here, a joint team of Lufthansa Technik experts and AM specialists from industry partners and research institutions develops strategies to support the introduction of this technology.
Dr. Aenne Koester, who heads the AM Center, explains: "While almost all product divisions of Lufthansa Technik have gathered considerable experience in this area, the new AM Center will serve as a collaborative hub where the experience and skills that Lufthansa Technik has gained in relation to additive manufacturing can be bundled and further expanded. Its aim is to increase the degree of maturity of the technologies and to develop products that are suitable for production."
For Lufthansa Technik as an MRO provider, a key focus is obviously set on the development of repair processes. This poses quite a challenge, as the standards in the aviation industry are still rudimentary or in the process of development, and the goals of the parties involved – OEMs and MROs – differ substantially. As one example from a number of ongoing research projects with different partners, the cooperation with Oerlikon aims at enhancing the understanding of process repeatability, a key element of industrialization and certification. To this end, representative component geometries will be printed on identical printers in three locations, one of them in Hamburg, Germany. Using three printers in three locations will help to achieve a better understanding of all parameters influencing the performance of a part manufactured using AM. The ultimate goal of the triple test is to shrink the process tolerance and to establish methods and standards which ensure that the desired performance goals are achieved with the required level of certainty.
With a focus on nickel-based alloys, highly-stressed engine components are of special interest for the AM development team. Lufthansa Technik has already made significant progress in this area. Currently the MRO provider is one of very few companies capable of performing what is called a powder bed fusion hybrid batch repair – an AM process in which a damaged part such as a blade is repaired by replacing lost material. It goes without saying that such a process requires extremely tight tolerances, not just in workholding.