Non-equilibrium phase behavior and friction of confined molecular films under shear: A non-equilibrium molecular dynamics study

非平衡态热力学 材料科学 相图 润滑 打滑(空气动力学) 分子动力学 摩擦学 表面光洁度 剪切(地质) 磁滞 凝聚态物理 机械 相(物质) 热力学 复合材料 物理 量子力学
作者
Sz. Maćkowiak,D. M. Heyes,Daniele Dini,A. C. Brańka
出处
期刊:Journal of Chemical Physics [American Institute of Physics]
卷期号:145 (16) 被引量:27
标识
DOI:10.1063/1.4965829
摘要

The phase behavior of a confined liquid at high pressure and shear rate, such as is found in elastohydrodynamic lubrication, can influence the traction characteristics in machine operation. Generic aspects of this behavior are investigated here using Non-equilibrium Molecular Dynamics (NEMD) simulations of confined Lennard-Jones (LJ) films under load with a recently proposed wall-driven shearing method without wall atom tethering [C. Gattinoni et al., Phys. Rev. E 90, 043302 (2014)]. The focus is on thick films in which the nonequilibrium phases formed in the confined region impact on the traction properties. The nonequilibrium phase and tribological diagrams are mapped out in detail as a function of load, wall sliding speed, and atomic scale surface roughness, which is shown can have a significant effect. The transition between these phases is typically not sharp as the external conditions are varied. The magnitude of the friction coefficient depends strongly on the nonequilibrium phase adopted by the confined region of molecules, and in general does not follow the classical friction relations between macroscopic bodies, e.g., the frictional force can decrease with increasing load in the Plug-Slip (PS) region of the phase diagram owing to structural changes induced in the confined film. The friction coefficient can be extremely low (∼0.01) in the PS region as a result of incommensurate alignment between a (100) face-centered cubic wall plane and reconstructed (111) layers of the confined region near the wall. It is possible to exploit hysteresis to retain low friction PS states well into the central localization high wall speed region of the phase diagram. Stick-slip behavior due to periodic in-plane melting of layers in the confined region and subsequent annealing is observed at low wall speeds and moderate external loads. At intermediate wall speeds and pressure values (at least) the friction coefficient decreases with increasing well depth of the LJ potential between the wall atoms, but increases when the attractive part of the potential between wall atoms and confined molecules is made larger.
最长约 10秒,即可获得该文献文件

科研通智能强力驱动
Strongly Powered by AbleSci AI
更新
PDF的下载单位、IP信息已删除 (2025-6-4)

科研通是完全免费的文献互助平台,具备全网最快的应助速度,最高的求助完成率。 对每一个文献求助,科研通都将尽心尽力,给求助人一个满意的交代。
实时播报
ding应助fengliurencai采纳,获得10
刚刚
荔枝完成签到 ,获得积分10
刚刚
1秒前
幸福大白发布了新的文献求助10
1秒前
hanleiharry1发布了新的文献求助10
2秒前
时笙发布了新的文献求助10
3秒前
5秒前
5秒前
翻斗花园小美完成签到,获得积分10
6秒前
8秒前
共享精神应助讨厌科研采纳,获得10
9秒前
余南发布了新的文献求助10
9秒前
10秒前
李子发布了新的文献求助10
10秒前
11秒前
量子星尘发布了新的文献求助10
13秒前
13秒前
13秒前
双楠应助SAVP采纳,获得10
14秒前
oui发布了新的文献求助10
15秒前
朴实桐应助花痴的语堂采纳,获得10
15秒前
15秒前
科目三应助东晓采纳,获得10
16秒前
loski发布了新的文献求助10
16秒前
清爽如雪完成签到 ,获得积分10
16秒前
Orange应助hanleiharry1采纳,获得10
19秒前
王海海发布了新的文献求助10
19秒前
20秒前
Xin发布了新的文献求助10
20秒前
mrx完成签到,获得积分20
21秒前
22秒前
孙燕应助光热效应采纳,获得30
25秒前
朴实桐应助花痴的语堂采纳,获得10
26秒前
香香完成签到,获得积分10
27秒前
大脑袋媛媛完成签到,获得积分10
28秒前
夏日发布了新的文献求助10
30秒前
30秒前
hanleiharry1发布了新的文献求助10
31秒前
32秒前
张雯思发布了新的文献求助10
32秒前
高分求助中
A new approach to the extrapolation of accelerated life test data 1000
ACSM’s Guidelines for Exercise Testing and Prescription, 12th edition 500
‘Unruly’ Children: Historical Fieldnotes and Learning Morality in a Taiwan Village (New Departures in Anthropology) 400
Indomethacinのヒトにおける経皮吸収 400
Phylogenetic study of the order Polydesmida (Myriapoda: Diplopoda) 370
基于可调谐半导体激光吸收光谱技术泄漏气体检测系统的研究 350
Robot-supported joining of reinforcement textiles with one-sided sewing heads 320
热门求助领域 (近24小时)
化学 材料科学 医学 生物 工程类 有机化学 生物化学 物理 内科学 纳米技术 计算机科学 化学工程 复合材料 遗传学 基因 物理化学 催化作用 冶金 细胞生物学 免疫学
热门帖子
关注 科研通微信公众号,转发送积分 3989390
求助须知:如何正确求助?哪些是违规求助? 3531487
关于积分的说明 11254109
捐赠科研通 3270153
什么是DOI,文献DOI怎么找? 1804887
邀请新用户注册赠送积分活动 882087
科研通“疑难数据库(出版商)”最低求助积分说明 809174