Screening design of hard metal feedstock powders for supersonic air fuel processing

• Published in: Surface & coatings technology 2014-11, Vol.258 (15 November), p.447-457
• Main Authors: Lyphout, Christophe, Sato, Katu
• Format: Article
• Language: English
• Subjects: Abrasion; Abrasion resistance; Abrasive wear; Applied sciences; carbides contiguity; Carbides grain size; Chromium; Coatings; Corrosion; Corrosion environments; Corrosion resistance; Cross-disciplinary physics: materials science; rheology; Design of experiment; erosion resistance; Exact sciences and technology; Feedstock; Grain size; HVAF; Manufacturing and materials engineering; Materials science; Metal powders; Metals. Metallurgy; Microstructure; Physics; Powder metallurgy. Composite materials; Production techniques; Produktions- och materialteknik; Surface treatments; WC-Co-Cr; WC-CoCr; Wear resistance
• ISSN: 0257-8972; 1879-3347; 1879-3347
• DOI: 10.1016/j.surfcoat.2014.08.055

Replacement of electrolytic hard chromium (EHC) method by Thermal Spray Technology has shown a growing interest the past decades, mainly pioneered by depositing WC-based material by conventional HVOF processes. Lower thermal energy and higher kinetic energy of sprayed particles achieved by newly-developed supersonic air fuel system, so-called HVAF-M3, significantly reduce decarburization, and increase wear and corrosion resistance properties, making HVAF-sprayed coatings attractive both economically and environmentally. In the present work, a first order process map has been intended via a full factorial design of experiments (DoE) to establish relationships between powder feedstock characteristics, such as primary carbides grain size, binder grain size and powder strength, and coating microstructure and mechanical properties. A second order process map was then established to study possible correlations between the deposit microstructural properties and their respective abrasion/erosion wear and corrosion performances. •Supersonic Air Fuel system, so-called HVAF-M3, is used to spray WC-Co-Cr powder.•Compared to conventional Process Window, Powder Design map has been here proposed.•Carbides grain size, Binder size and powder strength were selected as DoE factors.•Coarser carbides with finer binder increase the coating abrasion/erosion resistance.•Combining coarser carbides with high powder strength improve corrosion resistance.