Microstructure evolution and enhanced vacuum tribological performance of Ni-doped WS 2 composite coating

Tailoring the lubricative and electroconductive bifunction properties of NbSe2 film by controlling the sputtering plasma

“…The wear resistance of TMDs film mainly depended on the robust subsurface of wear track that acted as the supporter between the counterparts. The suitable density and occasional introduction of NbSe 3 and Nb 2 O 5 during S2 film growth process would tend to form the mixture phase at subsurface layer of wear track to enhance film wear resistance in the sliding process [11,27]. Based on the research results, the S2 NbSe 2 film with good crystalline and suitable densification exhibited relatively better electroconductive and tribological performances.…”

“…In this study, the inherent electroconductive performance of NbSe 2 crystal could be well reproduced in the superior NbSe 2 film. The densification of film and solid solution hardening effect by occasional introduction of NbSe 3 and Nb 2 O 5 during film growth process were also considered to be responsible for the hardness enhancement and high carrying capacity of NbSe 2 film.Moreover, the rearrangement of wear track surface layer with basal planes oriented parallel to the surface induced by friction interaction could play a main role on the low friction coefficient[25,27]. On the basis of chameleon principle[30], the non-lubricated NbSe 3 and Nb 2 O 5 would be selectively released from the wear track surface to the subsurface layer in the sliding process, which could tend to form a mixture phase of random NbSe 2 , NbSe 3 and Nb 2 O 5 and acted as the robust support layer for achieving high wear resistance.…”

Tribological Properties of 2D Materials and Composites—A Review of Recent Advances

“…Ding et al, showed that an increase in Cr doping on MoS 2 led to a substantial decrease in the wear rate and friction with humidity up to 9.6 at% of Cr as indicated in Figure 12 . Also, addition of metals such as Au [ 121 ], Cr [ 122 ], Ni [ 123 , 124 ], Cu [ 125 , 126 ], Zr [ 127 ], and metal compounds such as Sb 2 O 3 , WSe 2 have improved the performance under humid air and vacuum compared with sputter-deposited pure MoS 2 . Doping of WSe 2 in MoS 2 films leads to the substitution of sulfur atoms by selenide, which creates a curvature in the linear MoS 2 structure by increasing the interlayer spacing, as shown schematically in Figure 13 [ 128 ].…”

Tribological and dry drilling performance of WS₂/Cr-AlCrN coatings

“…WS 2 has superior lubricity (Xu et al, 2014;Scharf et al, 2006), thereby attracts growing attention as a kind of antifriction coating (Lian et al, 2018;Deepthi et al, 2018;Li et al, 2014), but WS 2 coating is not durable due to extremely low hardness. Therefore, doped WS 2 coatings were developed to improve their wear resistance, including WS 2 /Cr (Deepthi et al, 2010), WS 2 /Ni (Xu et al, 2017;Roy et al, 2017), WS 2 /Cu (Xu et al, 2014), WS 2 /Ag (Quan et al, 2017), WS 2 /Ti (Banerjee and Chattopadhyay, 2014), WS 2 /C (Cao et al, 2017), etc. Those works have proved that the proper content of doped element largely increased coating hardness and thermal stability as well as wear life, but the protective effect of doped WS 2 coatings is still far less than that of carbides/nitrides hard coatings.…”