Abstract
Additive manufacturing (AM) methods become more and more important due to improvements in the printing technology and availability of printers. As additive manufacturing is still a very expensive technology, it is predominantly used for complex parts in aerospace or medical applications. Especially in such demanding applications the properties of the parts are very important. In case of M50NiL, a carburizing heat resistant steel typically used for mainshaft bearings in aero engines, the development of an AM process and the properties of AM processed parts are shown. By comparison with specimens manufactured from conventional M50NiL it is demonstrated, that properties determined by optical microscopy, hardness testing, tensile testing, and rolling contact fatigue testing of M50NiL AM and M50NiL conventional manufactured are comparable.
Kurzfassung
Verfahren des „Additive Manufacturing“ (AM) erlangen durch Verbesserung der Anlagentechnik und steigender Anlagenverfügbarkeit immer mehr an Bedeutung. Bedingt durch die derzeit noch hohen Kosten wird diese Herstellungsmethode bevorzugt für komplexe, konventionell kaum oder nur sehr aufwendig herstellbare Teile in Bereichen wie Luftfahrt oder Medizintechnik angewendet. Gerade in derartigen Anwendungen werden aber hohe Anforderungen an die Bauteileigenschaften gestellt. Am Beispiel des für Triebwerkslager häufig verwendeten warmfesten Einsatzstahls M50NiL werden die Entwicklung eines AM-Prozesses und die Eigenschaften derartig gefertigter Teile beschrieben. Ein Vergleich mit konventionell gefertigten Proben zeigt, dass die mittels Lichtmikroskopie, Härtemessung, Zugversuchen und Überrollversuchen ermittelten Eigenschaften von AM-gefertigten Proben aus M50NiL mit denen konventionell gefertigter Teile vergleichbar sind.
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