Fabrication and evaluation of D-gun sprayed WC–Co coating with self-lubricating property

Abstract

A WC-Co coating with self-lubricating property was deposited by detonation gun (D-gun) process, using a commercial WC-Co powder doped with a MoS 2 -Ni powder, under a proper spray condition. It is proved that the MoS 2 composition in the feed powder was kept, which is attributed to the protection of Ni around it, and its content is a little higher in the resulting coating. Evaluation on sliding wear property indicates that the MoS 2 composition plays an important role in lowering both coefficient of friction and wear rate for the resulting coating, which is confirmed by observations on wear track, as well as X-ray photoelectron spectroscope (XPS) results on worn surface. It suggests that the deposition of WC-Co coating with self-lubricating property by D-gun spray is feasible by controlling lubricant powder and spray conditions, which can exhibit higher sliding wear resistance.

Cold-Sprayed Cu-MoS2 and Its Fretting Wear Behavior

“…For example, Hager Jr. et al have investigated that nickel graphite composite coatings are able to effectively mitigate fretting damage on titanium alloy compressor blades (Ref 3). Conventional manufacture of such materials includes powder metallurgy, hot pressing, sintering, and thermal spray ( Ref 1,[3][4][5][6][7][8]. However, those methods inevitably cause high-temperature-induced decomposition of solid lubricants and/or other phase transformations that could be detrimental for tribological performance (Ref 1, 5, 2 9).…”

Improving the high-temperature oxidation resistance of H13 steel by laser cladding with a WC/Co-Cr alloy coating

“…Co-based coatings can be fabricated by many methods. Co-based coatings applied using spraying methods are mechanically bonded to the substrate (Wang et al , 2010; Sobolev et al , 1998; Du et al , 2006). Tungsten inert gas (TIG) cladding is an economical surface alloying method, which provides a metallurgical bond between the substrate and the cladding coating (Mridha, 2005; Dyuti et al , 2011).…”

Fabrication and evaluation of atmospheric plasma spraying WC–Co–Cu–MoS2 composite coatings

“…However, Usmani et al [7], and Stewart et al [8] reported disappointing sliding wear and abrasive wear resistances of nanostructured WC-Co coatings for the increased decarburization. One promising way to improve wear resistance of thermal sprayed coatings is selflubrication by doping lubricant in them, which is cheaper and easier than the optimization for nanostructured coatings [9]. Selflubricating composites were introduced by Alexeyev and Jahanmir [10].…”