Reducing the adhesion and friction forces of Si by coating ultra-thin Al₂O₃ films

Abstract

Si-based microelectromechanical system (MEMS) devices cannot run reliably because of their poor tribological performance.

Understanding integrated effects of humidity and interfacial transfer film formation on tribological behaviors of sintered polycrystalline diamond

“…Experimental 11,16,24,28 The effects of dangling bonds passivation will be described in detail hereinafter. Experimental 11,16,24,28 The effects of dangling bonds passivation will be described in detail hereinafter.…”

“…Experimental elucidation of the role of humidity with dangling bond passivation theory of the H-terminated, OH-terminated surface and the formation of transfer lm on the friction of diamond materials is complicated by the fact that it can be difficult to isolate the inuence of these factors on adhesion and friction. 11,16,24,28 The effects of dangling bonds passivation will be described in detail hereinaer.…”

“…14 Many investigations have demonstrated that the formation of carbonaceous transfer layer on sliding ceramic counterbodies often influences tribological properties of diamond materials. 28 Next one, according to Tabor's adhesion theory, 29 the frictional force provides the energy to break the bonds formed at the interface of contact between the carbon atoms from the two surfaces. 27 Diamond surfaces saturated by the dissociative adsorption of water molecule can decrease the adhesion interaction at the sliding interface supported by ab initio density functional theory (DFT) calculations and molecular dynamics simulations.…”

“…27 Diamond surfaces saturated by the dissociative adsorption of water molecule can decrease the adhesion interaction at the sliding interface supported by ab initio density functional theory (DFT) calculations and molecular dynamics simulations. 28 Next one, according to Tabor's adhesion theory, 29 the frictional force provides the energy to break the bonds formed at the interface of contact between the carbon atoms from the two surfaces. Due to the large amounts of dangling bonds which are not saturated by adsorbed species in vacuum, the adhesion theory successfully explains the frictional mechanism of diamond sliding on diamond in vacuum exhibiting higher friction coefficient value (0.5-1 compared to values between 0.05-0.15 in air) by forming intense adhesive.…”

Oxidation behavior of the TiAlN hard coating in the process of recycling coated hardmetal scrap

“…We have previously reported the use of the zinc process for recycling WC-Co hardmetal tool tips with titanium carbonitride (TiCN)/ aluminum oxide (Al 2 O 3 )/titanium nitride (TiN) coatings. 7 The result revealed that pieces of Al 2 O 3 coatings were found in reclaimed WC powders. It is clear that Al 2 O 3 is well known for its excellent stability, and it is therefore not easily attacked by other chemicals or decomposed.…”