Cold-Sprayed Cu-MoS2 and Its Fretting Wear Behavior

Abstract

Cu and Cu-MoS2 coatings were fabricated by cold spray and the fretting wear performance of the two coatings was compared. A mixture (95 wt.% Cu + 5 wt.% MoS2) was used as feedstock for the composite coating. Coatings were sprayed with identical gas flow conditions on the substrates preheated to approximately 170C. The morphology of coating top surface and polished cross sections was analyzed by scanning electron microscopy (SEM) and light optical microscopy (LOM). The influence of MoS2 on Cu deposition was examined. The local MoS2 concentration within the coating was found to affect the hardness. Fretting tests were carried out at two different normal loads and the influence of MoS2 on friction and wear was studied. The morphology and elemental composition of the wear scars and wear debris were observed by SEM and energy dispersive X-ray spectroscopy (EDS), respectively.

Dry sliding wear behaviour of cold-sprayed Cu-MoS2 and Cu-MoS2-WC composite coatings: The influence of WC

“…2a and b, respectively. The dark contrast along the particle boundaries is MoS2, as shown in our previous work [16,17]. In Fig.…”

“…100 cycles in both composite coatings (see Fig. [14][15][16][17]. This material flow pattern was believed to be similar to that occurred in fluid flow [42].…”

“…During coating deposition, the gun traverse speed was 60 mm/s. Those spraying parameters were also applied in our previous work for fabrication of Cu-MoS2 composite [16,17].…”

Influence of Ultrasonic Surface Rolling Process and Shot Peening on Fretting Fatigue Performance of Ti-6Al-4V

“…Surface strengthening refers to the process of changing the structure of the material surface by applying external force or heat treatment, so as to improve the surface strength, hardness, fatigue resistance, wear resistance, surface integrity. Some common surface strengthening processes in engineering mainly include wet shot-peening [6][7], laser shock [8][9], surface coating [10][11], composite surface strengthening treatment [12][13], etc. A large number of studies have shown that surface strengthening improves the fatigue resistance of materials mainly due to the introduction of residual compressive stress.…”

Influence of WC on third body behaviour during fretting of cold-sprayed Cu MoS2WC composites

“…Our previous study on SLMMC coatings of Cu-MoS2 under gross slip regime demonstrated that presence of MoS2 facilitated fast development of wear debris bed that separated two first bodies and hence protected them from further wear at a low normal load (i.e. 100 N), while at 150 N normal load, a sharp raise in wear volume took place due to poor bonding between Cu and MoS2 [10]. This transition from mild wear to severe wear regimes with increasing normal load was commonly observed in SLMMCs [11].…”