The complex dynamics of tribofilm formation on boundary-lubricated steel surfaces were investigated in real time by combining in situ measurements of the temporal variation of the coefficient of friction and contact voltage. Sliding experiments were performed with various blends consisting of base oil, zinc dialkyl dithiophosphate (ZDDP) additive, and two different dispersants at an elevated oil temperature for a wide range of normal load and fixed sliding speed. The evolution of the transient and steady-state coefficient of friction, contact voltage, and critical sliding distance (time) for stable tribofilm formation were used to evaluate the tribological performance of the tribofilms. The blend composition affected the load dependence of the critical sliding distance for stable tribofilm formation. Tribofilm friction was influenced by competing effects between the additive and the dispersants. Among various formulations examined, the tribofilm with the best friction characteristics was found to be the blend consisting of base oil, a small amount of ZDDP, and a bis-succinimide dispersant treated with ethylene carbonate. The results of this study demonstrate the effectiveness of the present experimental approach to track the formation and removal of protective tribofilms under boundary lubrication conditions in real time.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC10972069 | PMC |
http://dx.doi.org/10.3390/ma17061335 | DOI Listing |
Langmuir
December 2024
State Key Laboratory of Fluorinated Functional Membrane Materials, Dongyue Fluorosilicone Technology Group, Zibo 256400, China.
Three α-alkene lubricants, differentiated by chain length, were selected as model compounds to investigate the influence of chain length on tribological properties. The novelty of this study lies in setting chain length as the sole variable to explore its impact on surface and adsorption energy. Based on the above findings, the study provides a unique explanation of the intrinsic relationship between chain length and tribological performance.
View Article and Find Full Text PDFLangmuir
December 2024
Department of Chemistry, University of Kerala, Kariavattom Campus, Thiruvananthapuram, Kerala 695 581, India.
The relentless wear and friction of steel-based moving machinery have created ongoing challenges that hinder their industrial applications. One promising solution is the use of reduced graphene oxide (rGO) as a lubricant due to its excellent mechanical strength and promising tribological properties. However, its tendency to self-agglomerate presents a major hurdle for its practical use.
View Article and Find Full Text PDFNanomaterials (Basel)
October 2024
Department of Mechanical Engineering, Auckland University of Technology, Auckland 1010, New Zealand.
This study highlights the impact of low amounts of MoS quantities on composite performance by examining the effects of ultrasonication exfoliated MoS at different loadings (0.1-0.5 wt%) on the mechanical and tribological parameters of epoxy composites.
View Article and Find Full Text PDFACS Appl Mater Interfaces
October 2024
State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
MXenes, a novel class of two-dimensional materials, possess exceptional physical and chemical properties, positioning them as promising candidates for lubricant additives. However, their potential is constrained by challenges in dispersion and stability, coupled with a paucity of research on interactions with additives in full-formula oils. In this study, hexadecylphosphonic acid (HDPA) is grafted onto TiCT to formulate a polyalkylene glycol dispersion system.
View Article and Find Full Text PDFMater Horiz
October 2024
Key Laboratory of Advanced Marine Materials, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
Robustness and environmental adaptability are crucial for molybdenum disulfide (MoS) films to minimize friction and wear in industrial applications. However, current sputtered MoS films suffer from inherent defects, including insufficient hardness, poor crystallinity, and susceptibility to oxidation, thereby limiting their longevity and reliability. Here, we present a sandwich-like nanomultilayer architecture comprising alternating MoS and tungsten carbide (WC) layers integrated with Ag nanoparticles.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!