Xiangle Kong , Deping Wang , Xiaoyu Zhou , Jianxiang Zhang , Xuan Niu , Yongfeng Jiang , Minghui Bai , Lun Li , Jun Li , Jianfeng Wang , Weihua Li
{"title":"Runner-ice friction models for winter olympic bobsleigh","authors":"Xiangle Kong , Deping Wang , Xiaoyu Zhou , Jianxiang Zhang , Xuan Niu , Yongfeng Jiang , Minghui Bai , Lun Li , Jun Li , Jianfeng Wang , Weihua Li","doi":"10.1016/j.triboint.2025.110650","DOIUrl":"10.1016/j.triboint.2025.110650","url":null,"abstract":"<div><div>Bobsleigh, a quintessential team winter sport, involves high-velocity ice traversal on meticulously crafted tracks. Understanding the friction between the runner and ice surface is crucial for grasping the sport's dynamics. In this investigation, we introduce an advanced dynamic model that captures the complex relationship between friction, bobsleigh velocity, side slip angle, and the load on the ice surface. We also introduce a novel testing system for runner-ice mechanical property, which accurately simulates real-world bobsleigh conditions through its modular test rig and comprehensive measurement approach. Through precise coefficient identification for the model's unknown parameters, we enhanced the model's predictive accuracy and refinement. The results showed R-squared values of 0.967 for the lateral model and 0.942 for the longitudinal model.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"208 ","pages":"Article 110650"},"PeriodicalIF":6.1,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143687274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zehao Qin , Nan Kang , Ruidi Li , Wenling Zhang , Mohamed El Mansori
{"title":"Microstructure and wear behavior of Mn-modified high-strength AlCu alloy fabricated via laser powder bed fusion","authors":"Zehao Qin , Nan Kang , Ruidi Li , Wenling Zhang , Mohamed El Mansori","doi":"10.1016/j.triboint.2025.110660","DOIUrl":"10.1016/j.triboint.2025.110660","url":null,"abstract":"<div><div>In this work, a new Mn-modified Al<img>Cu<img>Mg<img>Si<img>Ti alloy with a high relative density of 99.5 % was processed via laser powder bed fusion (LPBF) technology. The influence of Mn addition on the solidification microstructure was investigated through multiscale characterization methods, and the wear behavior of the modified alloy was evaluated via a ball-on-flat tribometer against 100Cr6 steel under three different loads (2.1 N, 10 N, and 24 N). The results demonstrate that the formation of bimode columnar<img>equiaxed grains is attributed to the addition of Ti with nanosized Al<sub>3</sub>Ti particles, whereas Mn is oversaturated and solid-solved within the matrix, with no significant Mn precipitation observed. This oversaturation increases the distortion of the Al matrix, improving the strain hardening capability and oxidation resistance of the material. As a result, the wear rates after Mn modification were reduced by 78.4 %, 66.7 %, and 56.8 % under 2.1 N, 10 N, and 24 N loads, respectively, compared with those of the LPBF Al<img>Cu<img>Mg<img>Si<img>Ti alloy.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"208 ","pages":"Article 110660"},"PeriodicalIF":6.1,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143643866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Feng Qiu, Hui Song, Zhiquan Yang, Mingliang Jiang, Xianguo Hu
{"title":"Atomic-scale insights into the mechanical and tribological properties of graphullerene","authors":"Feng Qiu, Hui Song, Zhiquan Yang, Mingliang Jiang, Xianguo Hu","doi":"10.1016/j.triboint.2025.110656","DOIUrl":"10.1016/j.triboint.2025.110656","url":null,"abstract":"<div><div>Graphullerene (GF) as an emerging two-dimensional nanomaterial exhibits excellent flexibility properties and superlubricity potential, but current research on its mechanical and tribological properties still lacks in-depth insights from the microscopic scale. Herein, the mechanical strength of GF was explored and its tribological mechanisms as a lubricant additive in fluid and boundary lubrication states were revealed by indentation, tensile, and friction molecular dynamics simulations using graphene (GR) as a comparative object. The results revealed that compared with GR, covalent bond mixed hybridization reduced the mechanical strength of GF, but the robust spherical structure enhanced its bending stiffness. Under fluid lubrication, GR promoted adsorption film formation and rapid flow to induce low-shear strength solid-liquid interfacial slip. GF inhibited this characteristic and thus induced liquid-liquid interlayer slip with high frictional resistance. Under boundary lubrication, GR exhibited superior tribological performance compared to GF, with the bilayer outperforming the monolayer. This was attributed to the high bending stiffness of GF inhibiting the bending deformation releasing stresses and thus deteriorating the mechanical contact with the asperity. However, friction-induced interlayer slip of bilayer nanoparticles with low shear strength. This study provides valuable insights into the mechanical and tribological properties of GF.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"208 ","pages":"Article 110656"},"PeriodicalIF":6.1,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143687089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Peng Ding , Wenhui Cao , Qi Ding , Chaobin Liu , Wei Yu , Litian Hu
{"title":"The influence of mechanical shearing on the thickener microstructure and properties of Polyurea greases","authors":"Peng Ding , Wenhui Cao , Qi Ding , Chaobin Liu , Wei Yu , Litian Hu","doi":"10.1016/j.triboint.2025.110655","DOIUrl":"10.1016/j.triboint.2025.110655","url":null,"abstract":"<div><div>Polyurea (PU) greases have found widespread applications in harsh working conditions. While the influence of PU molecule and thermal treatment condition on the microstructure and properties of PU greases has been well elucidated, the impact of mechanical shearing remains unclear. This study explored how mechanical shearing during production affects the structure and properties of PU grease made from octylamine and 4,4′-diphenylmethane diisocyanate. It was found that static heat treatment leads to nanotube structures, while stirred heat treatment creates twisted fibers. Shearing flow is shown to influence the formation of these structures. The nanotube PU grease has lower consistency and better lubrication for high-speed conditions, while the twisted fiber grease offers higher consistency and stability, suited for boundary lubrication.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"208 ","pages":"Article 110655"},"PeriodicalIF":6.1,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143705041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Tribological properties and molecular dynamics analysis of citric acid modified 3D porous graphene/carbon black as lubricant additives","authors":"Jingjing Fei , Lianfei Zhao , Qingpeng Zheng , Wentian Wei , Lizhe Liang , Zhi Qun Tian","doi":"10.1016/j.triboint.2025.110648","DOIUrl":"10.1016/j.triboint.2025.110648","url":null,"abstract":"<div><div>Graphene holds significant potential as a green additive for lubricating oils, but its poor dispersion stability limits its applications. In this study, citric acid-modified graphene (CAG) was prepared by modifying 3D porous graphene with citric acid, achieving stable dispersion in lubricating oil for up to six months without the need for dispersants. The lubricating properties were investigated using a four-ball friction tester, and wear scars were characterized using the depth-of-field microscope, Scanning electron microscopy (SEM), and Raman spectroscopy. The experimental results demonstrated that adding a composite (CC) of CAG and carbon black to castor oil reduced the coefficient of friction (COF) and anti-wear by 24.57 % and 70.27 %, respectively, under a load of 392 N. Under a load of 588 N, the COF and anti-wear decreased by 32.59 % and 56.54 %, respectively, while the last non-seizure load (P<sub>B</sub>) increased by 125.26 %. The sheet-like CAG adsorbed onto the friction surface, enhancing the oil film's load-carrying capacity, while the spherical carbon black acted as microbearings, converting part of the sliding friction into rolling lubrication. A synergistic effect between CAG and carbon black was observed, with the composite exhibiting better lubricating performance than either material alone. Moreover, molecular dynamics simulation results revealed that adding CAG alone enhanced the lubricant's adsorption but reduced its mobility. The combined addition of CAG and carbon black retained the improved adsorption while enhancing the lubricant's mobility, further confirming the synergistic action between CAG and carbon black.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"208 ","pages":"Article 110648"},"PeriodicalIF":6.1,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143687291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shu Yang , Zhenyu Liu , Shaoqi Zhang , Wanshun Wang , Guodian Huang , Longshen Lu , Yingxi Xie
{"title":"Self-lubricating film formation and ultra-low wear of PTFE/aluminum through anodization induced nano-microtextures","authors":"Shu Yang , Zhenyu Liu , Shaoqi Zhang , Wanshun Wang , Guodian Huang , Longshen Lu , Yingxi Xie","doi":"10.1016/j.triboint.2025.110657","DOIUrl":"10.1016/j.triboint.2025.110657","url":null,"abstract":"<div><div>Polytetrafluoroethylene (PTFE) can transfer its material to counterfaces during sliding, forming a self-lubricating transfer film. Previous studies have demonstrated that surface morphology influences the formation of transfer films, and nano-microtextures have been shown to increase the wear of PTFE. In this study, nano-microtextures were created on the surface of aluminum alloys by phosphoric acid anodization. The results show that the nano-microtextures regulates the debris size, and the mechanical interlocking between the debris and the nano-microtextures facilitates the stabilization of the transfer film. The increase in surface energy boosts the capacity for debris adsorption on the surface, which promotes tribochemical reaction, enhancing the adhesion and cohesion of the transfer film and further improving the stability of the transfer film.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"208 ","pages":"Article 110657"},"PeriodicalIF":6.1,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143687180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rui Gao , Yee Man Loh , Kangsen Li , Rui Chen , Chen Jiang , Chi Fai Cheung , Chunjin Wang
{"title":"Study on the material removal mechanism of cemented carbide magnetic materials in magnetic field-assisted mass polishing","authors":"Rui Gao , Yee Man Loh , Kangsen Li , Rui Chen , Chen Jiang , Chi Fai Cheung , Chunjin Wang","doi":"10.1016/j.triboint.2025.110647","DOIUrl":"10.1016/j.triboint.2025.110647","url":null,"abstract":"<div><div>Cemented carbides (WC-Co) are crucial in modern engineering due to their exceptional hardness, wear resistance, and toughness, making them ideal for various applications. Despite advancements in polishing techniques, the mechanisms for polishing WC-Co magnetic materials using magnetic field-assisted methods remain inadequately understood. This study addresses these gaps by investigating the material removal mechanism of WC-Co after electrical discharge machining (EDM) using the proposed magnetic field-assisted mass polishing (MAMP) method. A material removal distribution (MRD) model of different magnetic materials was developed to guide the experiments. Key findings include significant reductions in surface roughness, effective removal of oxide layers formed during EDM, and improved polishing uniformity and efficiency. The study also demonstrated the MAMP method’s ability to maintain the form integrity of structured surfaces. This research enhances the understanding of polishing mechanisms for magnetic materials and presents a viable method for improving the surface quality of WC-Co. This research provides valuable insights into the polishing mechanisms of magnetic materials using magnetic field-assisted polishing methods.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"208 ","pages":"Article 110647"},"PeriodicalIF":6.1,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143687425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Cumulative effect of FexN phases, roughness parameters, and asperity geometry on the anti-wear properties of low-temperature plasma nitrided Ti-Nb stabilized IF steel","authors":"Bibekananda Sahoo , K. Udaya Bhat","doi":"10.1016/j.triboint.2025.110652","DOIUrl":"10.1016/j.triboint.2025.110652","url":null,"abstract":"<div><div>Plasma-driven surface modification techniques like plasma nitriding (PN) are trending, especially for steel products. It is advantageous due to the higher order of process control and superior quality of property enhancement of the surface. This technique often employs a high processing temperature, which is one of its metallurgical and economical limitations. One of the renowned solutions is the implementation of lower processing temperatures. The current work is based on the low-temperature plasma nitriding of Ti-Nb stabilized interstitial-free steel at different processing temperatures ranging from 400 ºC to 500 ºC. The role of Fe<sub>x</sub>N phases, surface roughness parameters, and asperities geometry are thoroughly studied with respect to the anti-wear properties of the surface. The formation of γ′-Fe<sub>4</sub>N and ε-Fe<sub>2–3</sub>N are detected in the XRD plot, whereas α″-Fe<sub>16</sub>N<sub>2</sub> is confirmed in microscopy. The sample treated at 450 ºC presents the best anti-wear properties compared to other samples, primarily due to the presence of prominent ε-Fe<sub>2–3</sub>N phase and blunt surface asperities. A maximum reduction in wear volume of about 3 times the base value is recorded in the wear test. The microscopic and elemental analyses are conducted on the wear scars, wear debris, and counter-body worn-out surfaces to study the wear mechanism comprehensively. The work tries to illustrate the wear mechanisms schematically to understand the conceptual grounds associated with such theories. The spectrometric analysis in the depth direction is also performed, and it detects the trace of nitrogen up to about 7 µm depth for 500 ºC nitriding conditions.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"208 ","pages":"Article 110652"},"PeriodicalIF":6.1,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143687183","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Achieving oil-based superlubricity with near-zero wear via synergistic effect between PEEK-PTFE and PAO40 containing DDP-Cu nanoparticles","authors":"Shanshan Li , Chuanping Gao , Chunjian Duan , Shengmao Zhang , Pingyu Zhang , Zhijun Zhang","doi":"10.1016/j.triboint.2025.110645","DOIUrl":"10.1016/j.triboint.2025.110645","url":null,"abstract":"<div><div>Oil-based superlubricity introduces a novel approach to energy conservation. Facing two main obstacles at present, i.e., higher viscosity of lubricating oil and special tribopairs, a novel solid-liquid combined system is built in this work, which is mainly based on excellent tribological property of oil-soluble dialkyl-dithiophosphoric-modified Cu nanoparticles (DDP-Cu NPs) and superior self-lubricating capability of polymeric tribopairs. In this system, polyetheretherketone (PEEK) is coupled with polytetrafluoroethylene (PTFE) to form a similar/dissimilar tribopair; and neat PAO40 (a real serving lubricating oil with high viscosity in poly-alpha olefin oil family), or PAO40 containing oil-soluble DDP-Cu NPs (PAO40 + Cu), is used as a lubricant during the sliding test. The results show that only dissimilar tribopair, i.e., PEEK-PTFE, can achieve oil-based superlubricity under the selected sliding conditions, which can be attributed to the synergistic effect between PEEK-PTFE tribopair and PAO40/PAO40 + 0.25 Cu. Furthermore, due to lower cohesive energy density (CED), PTFE is more likely to be transferred onto PEEK together with some tribochemical reactions, finally generating a high-performance tribofilm rich in carboxylated PTFE. In addition, it is concluded that, when lubricated with PAO40, the above synergistic effect is a key to achieve superlubricity; and for PAO40 + 0.25 Cu, the carboxylated PTFE and the exposed Cu core will create chelate effect, which can not only further enhance this synergistic effect, but also improve the wear-resistance of the system reaching near-zero wear. This work not only provides a novel idea for designing oil-based superlubricity system, but broadens the type of tribopair materials achieving oil-based superlubricity to some extent.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"208 ","pages":"Article 110645"},"PeriodicalIF":6.1,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143687276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Discussion of “Prediction of pavement friction coefficient based on dynamic friction test simulation”","authors":"Yunwei Meng , Zixiao Wang , Hang Lu","doi":"10.1016/j.triboint.2025.110649","DOIUrl":"10.1016/j.triboint.2025.110649","url":null,"abstract":"<div><div>This discussion critically evaluates the paper \"Prediction of Pavement Friction Coefficient Based on Dynamic Friction Test Simulation\" by Luo et al. While the proposed finite element (FE) modeling framework offers a novel method for predicting the coefficient of friction (COF) using the FE (finite element) model, it exhibits significant limitations, particularly in its treatment of adhesive and hysteretic friction components, leading to potential underpredictions of COF. The inappropriate application of the Persson model raises further accuracy concerns, especially at higher speeds. This discussion advocates for back-calculation methods and emphasizes the need for friction test validation. Future research should aim to enhance the model by incorporating additional factors such as temperature and material properties for improved reliability.</div></div>","PeriodicalId":23238,"journal":{"name":"Tribology International","volume":"208 ","pages":"Article 110649"},"PeriodicalIF":6.1,"publicationDate":"2025-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143687145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}