Laser-based directed energy deposition and characterisation of cBN-reinforced NiAl-based coatings

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

  • Michael Müller - , Professur für Werkstofftechnik, Fraunhofer-Institut für Werkstoff- und Strahltechnik (Autor:in)
  • Leonid Gerdt - , Fraunhofer-Institut für Werkstoff- und Strahltechnik (Autor:in)
  • Susanne Schrüfer - , Rolls-Royce Deutschland (Autor:in)
  • Mirko Riede - , Fraunhofer-Institut für Werkstoff- und Strahltechnik (Autor:in)
  • Elena López - , Fraunhofer-Institut für Werkstoff- und Strahltechnik (Autor:in)
  • Frank Brueckner - , Fraunhofer-Institut für Werkstoff- und Strahltechnik, Luleå University of Technology (Autor:in)
  • Christoph Leyens - , Professur für Werkstofftechnik, Fraunhofer-Institut für Werkstoff- und Strahltechnik (Autor:in)

Abstract

Abstract: Within this study, the alloy NiAl–2.5Ta–7.5Cr is investigated as a new matrix material for cBN-reinforced abrasive turbine blade tip coatings as currently used NiCoCrAlY matrix alloys suffer from insufficient strength at the high operating temperatures. Laser-based directed energy deposition with blown powder was applied to produce cBN reinforced NiAl-based coatings on monocrystalline CMSX-4 substrates. For this, powdery titanium-coated cBN and NiAl–2.5Ta–7.5Cr material were co-injected into the process zone to achieve an in situ formation of a NiAl–2.5Ta–7.5Cr/cBN composite. In order to overcome challenges such as cracking susceptibility, inductive preheating of the substrate up to 800 °C was used. Optical and scanning electron microscopy, energy dispersive X-ray spectroscopy, as well as electron backscatter diffraction were applied to analyse the fabricated samples’ microstructure. Additionally, the mechanical properties were evaluated by means of microhardness mappings. This work demonstrates the feasibility of in situ forming a metal matrix composite with a homogeneous distribution of cBN particles. The results show the beneficial effect of high-temperature preheating on the crack formation. However, the study also reveals challenges such as cracking induced by the injected cBN particles as well as severe intermixing of substrate and coating, which yields spatially resolved deviations in the chemical composition and resulting variations in microstructure and hardness. Graphical abstract: (Figure presented.)

Details

OriginalspracheEnglisch
Seiten (von - bis)657-675
Seitenumfang19
FachzeitschriftInternational Journal of Advanced Manufacturing Technology
Jahrgang134
Ausgabenummer1-2
PublikationsstatusVeröffentlicht - Sept. 2024
Peer-Review-StatusJa

Schlagworte

Schlagwörter

  • Additive manufacturing, Advanced materials, Coatings, Directed energy deposition, Intermetallics, Nickel aluminide