Emerging processes for metallurgical coatings and thin films

Alain Billard (1) , Francis Maury (2) , Pascal Aubry (3) , Fanny Balbaud-Célérier (3) , Benjamin Bernard (4) , Fernando Lomello (3) , Hicham Maskrot (3) , Erick Meillot (4) , Alexandre Michau (3) , Frédéric Schuster (3)

1 FEMTO-ST - Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174)
2 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux
3 CEA-DES (ex-DEN) - CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire)
4 CEA Le Ripault - CEA Le Ripault

Innovation in thin-film deposition processes, thermal spraying and cladding technologies mostly rely on evolutions of their previous iteration. Along with other examples, five case studies of emerging elaboration processes for metallurgical coatings are described coupled with their applications. In the frame of the lifetime extension of components exposed to aggressive media or their functionalization, this article depicts all the developments of the detailed processes. Physical vapor deposition (PVD) of coatings with exceptional properties is possible thanks to sources generating highly ionized metallic vapors. The control of the average energy per incident species and particularly metallic ions strongly influences the characteristics of the deposited layer obtained, for example, with HiPIMS (High Power Impulse Magnetron Sputtering). While PVD techniques are mainly directive regarding the growth of the coating, chemical vapor deposition (CVD) processes manage to homogeneously coat complex 3D shapes. The use of specific precursors in DLI–MOCVD (Direct Liquid Injection – MetalOrganic CVD), carefully selected from the whole metalorganic chemistry, allows one to efficiently treat heat-sensitive substrates and broadens their application range. The third detailed example of emerging technology is suspension plasma spraying (SPS). Projection of various solutions containing nanoparticles leads to the growth of unusual morphologies and microstructures and to the generation of porous coatings with multi-scaled porosity. On the other hand, cold-spray uses metallic powders with higher granulometry and does not modify them during the deposition process. As a result, high-purity and dense materials are deposited with properties similar to those of wrought materials. Whereas cold-spray is suitable only for ductile metals, laser cladding can be applied to ceramics, polymers and of course metals. Laser cladding is a key technology for advanced metallurgical engineering and alloy development due to its capability for functionally graded materials production and combinatorial synthesis.

Mots clés: Projection Rechargement laser; Pulvérisation magnétron; Dépôt chimique

Domaines: Chimie inorganique; Matériaux

Alain Billard, Francis Maury, Pascal Aubry, Fanny Balbaud-Célérier, Benjamin Bernard, et al.. Emerging processes for metallurgical coatings and thin films. Comptes Rendus. Physique, 2018, 19 (8), pp.755-768. ⟨10.1016/j.crhy.2018.10.005⟩. ⟨hal-02368690⟩