Anti-spreading behavior of 1,3-diketone lubricating oil on steel surfaces

Evaluation of 1,3-diketone as a novel friction modifier for lubricating oils

“…The additives which have both strong solid-fluid interactions and intermolecular interactions like liquid crystals are especially preferable. In our prior work [23][24][25][26][27][28][29][30][31] a synthetic 1,3-diketone (1-(4-ethyl phenyl) nonane-1,3-dione) oil (abbreviated as EPND) has been discovered as the first oily material of superlubricity achieved through experimental methods on the macroscopic scale. This molecule exhibits a rod-like structure similar to 5CB and supplies a high intermolecular force like liquid crystals [28] .…”

“…This molecule exhibits a rod-like structure similar to 5CB and supplies a high intermolecular force like liquid crystals [28] . It can reach an ultralow COF (≈0.005) on steel surfaces after a certain running-in period in both tribological reciprocating [28][29][30][31] and rotating [23][24][25][26][27] systems. Its superlubricity is attributed to two effects (Figure 1): (1) Through chelating with iron, the tribochemical reaction between EPND and the steel surface eliminates solid contacts and leads to a full fluid film [30] ; (2) The chemisorption of EPND on steel surfaces and its strong intermolecular interactions facilitate the molecular alignment and smaller shear resistance [25,28] .…”

Meta-Analysis Comparing Wettability Parameters and the Effect of Wettability on Friction Coefficient in Lubrication

“…While the role of lubricant viscosity is fairly well established [3,8], the effects of wettability across multiple wetting regimes is less well understood [6][7][8][9][10][11][12][13][14][15][16][17]. To improve the understanding of wettability in tribological systems, recent investigations have worked to characterize the wettability of a variety of novel lubricants [6,[12][13][14][15] and to understand the role of wettability in tribological performance [6][7][8]10,11,[16][17][18]. In HL, high wettability (and low contact angles) are often desirable.…”