{"title":"含水量对乙二醇溶液超润滑性的影响","authors":"Lvzhou Li, Peng Gong, Pengpeng Bai, Xiangli Wen, Yonggang Meng, Jianning Ding, Yu Tian","doi":"10.3390/lubricants11110466","DOIUrl":null,"url":null,"abstract":"Aqueous solutions of water and ethylene glycol (EG) are prevalently employed in braking, heat transfer, and lubrication systems. However, the precise mechanism through which water content affects the lubricative attributes of EG solutions remains elusive. This research systematically examines the tribological characteristics of EG solutions at varying concentrations using a ceramic–TiAlN friction-pair system. As the concentration of EG increases, the sequential transformation of the associated molecular complex structure in the lubricating medium can be described as follows: [H2O]m·EG → [H2O]m·[EG]n → H2O·[EG]n. Among them, the stoichiometric coefficients “m” and “n” are the simplest mole ratio of H2O and EG in the molecular complex structure, respectively. The most favorable EG concentration was determined to be 50 wt.%. At this concentration, a flexible molecular complex adsorption structure ([H2O]m·[EG]n) with a significant bearing capacity (due to intense hydrogen bonding) forms on the surface of the friction pair, which results in a reduction in the running-in duration and facilitates the achievement of superlubricity, and the coefficient of friction (COF) is about 0.0047. Solutions containing 50 wt.% EG enhance the load-bearing ability and hydrophilicity of the lubricating medium. Moreover, they minimize the roughness of the worn region and curtail the adhesive forces and shear stress at the frictional interface, enabling the realization of superlubricity. Consequently, this research offers valuable insights into the optimal water-to-EG ratio, revealing the mechanism of a superlubricity system that possesses exceptional tribological attributes and holds significant potential for practical applications.","PeriodicalId":18135,"journal":{"name":"Lubricants","volume":"96 4","pages":"0"},"PeriodicalIF":3.1000,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Impact of Water Content on the Superlubricity of Ethylene Glycol Solutions\",\"authors\":\"Lvzhou Li, Peng Gong, Pengpeng Bai, Xiangli Wen, Yonggang Meng, Jianning Ding, Yu Tian\",\"doi\":\"10.3390/lubricants11110466\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Aqueous solutions of water and ethylene glycol (EG) are prevalently employed in braking, heat transfer, and lubrication systems. However, the precise mechanism through which water content affects the lubricative attributes of EG solutions remains elusive. This research systematically examines the tribological characteristics of EG solutions at varying concentrations using a ceramic–TiAlN friction-pair system. As the concentration of EG increases, the sequential transformation of the associated molecular complex structure in the lubricating medium can be described as follows: [H2O]m·EG → [H2O]m·[EG]n → H2O·[EG]n. Among them, the stoichiometric coefficients “m” and “n” are the simplest mole ratio of H2O and EG in the molecular complex structure, respectively. The most favorable EG concentration was determined to be 50 wt.%. At this concentration, a flexible molecular complex adsorption structure ([H2O]m·[EG]n) with a significant bearing capacity (due to intense hydrogen bonding) forms on the surface of the friction pair, which results in a reduction in the running-in duration and facilitates the achievement of superlubricity, and the coefficient of friction (COF) is about 0.0047. Solutions containing 50 wt.% EG enhance the load-bearing ability and hydrophilicity of the lubricating medium. Moreover, they minimize the roughness of the worn region and curtail the adhesive forces and shear stress at the frictional interface, enabling the realization of superlubricity. Consequently, this research offers valuable insights into the optimal water-to-EG ratio, revealing the mechanism of a superlubricity system that possesses exceptional tribological attributes and holds significant potential for practical applications.\",\"PeriodicalId\":18135,\"journal\":{\"name\":\"Lubricants\",\"volume\":\"96 4\",\"pages\":\"0\"},\"PeriodicalIF\":3.1000,\"publicationDate\":\"2023-10-31\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Lubricants\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.3390/lubricants11110466\",\"RegionNum\":3,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"ENGINEERING, MECHANICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Lubricants","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.3390/lubricants11110466","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, MECHANICAL","Score":null,"Total":0}
Impact of Water Content on the Superlubricity of Ethylene Glycol Solutions
Aqueous solutions of water and ethylene glycol (EG) are prevalently employed in braking, heat transfer, and lubrication systems. However, the precise mechanism through which water content affects the lubricative attributes of EG solutions remains elusive. This research systematically examines the tribological characteristics of EG solutions at varying concentrations using a ceramic–TiAlN friction-pair system. As the concentration of EG increases, the sequential transformation of the associated molecular complex structure in the lubricating medium can be described as follows: [H2O]m·EG → [H2O]m·[EG]n → H2O·[EG]n. Among them, the stoichiometric coefficients “m” and “n” are the simplest mole ratio of H2O and EG in the molecular complex structure, respectively. The most favorable EG concentration was determined to be 50 wt.%. At this concentration, a flexible molecular complex adsorption structure ([H2O]m·[EG]n) with a significant bearing capacity (due to intense hydrogen bonding) forms on the surface of the friction pair, which results in a reduction in the running-in duration and facilitates the achievement of superlubricity, and the coefficient of friction (COF) is about 0.0047. Solutions containing 50 wt.% EG enhance the load-bearing ability and hydrophilicity of the lubricating medium. Moreover, they minimize the roughness of the worn region and curtail the adhesive forces and shear stress at the frictional interface, enabling the realization of superlubricity. Consequently, this research offers valuable insights into the optimal water-to-EG ratio, revealing the mechanism of a superlubricity system that possesses exceptional tribological attributes and holds significant potential for practical applications.
期刊介绍:
This journal is dedicated to the field of Tribology and closely related disciplines. This includes the fundamentals of the following topics: -Lubrication, comprising hydrostatics, hydrodynamics, elastohydrodynamics, mixed and boundary regimes of lubrication -Friction, comprising viscous shear, Newtonian and non-Newtonian traction, boundary friction -Wear, including adhesion, abrasion, tribo-corrosion, scuffing and scoring -Cavitation and erosion -Sub-surface stressing, fatigue spalling, pitting, micro-pitting -Contact Mechanics: elasticity, elasto-plasticity, adhesion, viscoelasticity, poroelasticity, coatings and solid lubricants, layered bonded and unbonded solids -Surface Science: topography, tribo-film formation, lubricant–surface combination, surface texturing, micro-hydrodynamics, micro-elastohydrodynamics -Rheology: Newtonian, non-Newtonian fluids, dilatants, pseudo-plastics, thixotropy, shear thinning -Physical chemistry of lubricants, boundary active species, adsorption, bonding