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Friction 2024年第2期12卷 305-318页

作者： Yangyang ZHAO Guoyuan ZHANG Junqian WANG He WANG Weigang ZHAO qunfeng zeng School of Mechano-Electronic Engineering Xidian UniversityXi’an 710071China Xi’an Aerospace Propulsion Institute Xi’an 710071China Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System Xi’an Jiaotong UniversityXi’an 710049China

The friction coefficient and wear rate of pretreated graphite with liquid nitrogen were obtained by using a ball-on-disk tester,and the wear of GCr15–graphite seal pairs with the low-temperature time-dependent pretreatment was discussed by comparing the wear *** results show that liquid nitrogen pretreatment can affect the hardness and interlayer spacing of *** range of the friction coefficients of pretreated graphite changes from 0.17 to *** the increase of liquid nitrogen pretreatment time,the wear mechanism of graphite would change from dominated three-body wear to adhesion *** experimental results of the mechanical seal with liquid nitrogen pretreatment show that the wear rate of stator is less than 0.00165 mm^(3)·N^(−1)·m^(−1),and the graphite shows a good low-temperature compatibility.

关键词： graphite low-temperature pretreatment mechanical seal friction and wear

碳化硅化学机械抛光中材料去除非均匀性研究进展

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人工晶体学报 2024年第4期53卷 585-599页

作者：孙兴汉李纪虎张伟曾群锋张俊锋中电建(西安)港航船舶科技有限公司西安710100 西安交通大学现代设计及转子轴承系统教育部重点实验室西安710049 上海船舶设备研究所上海200031

化学机械抛光已经成为半导体制造中关键的工艺步骤之一,该技术是目前实现碳化硅晶片超精密加工的一种常用且有效的方法,可用于加工晶片表面,以获得高材料去除率、高表面质量和高表面平整性的晶片。然而,在碳化硅晶片化学机械抛光中,晶... 详细信息

化学机械抛光已经成为半导体制造中关键的工艺步骤之一,该技术是目前实现碳化硅晶片超精密加工的一种常用且有效的方法,可用于加工晶片表面,以获得高材料去除率、高表面质量和高表面平整性的晶片。然而,在碳化硅晶片化学机械抛光中,晶片表面材料去除非均匀性一直是一个具有挑战性的问题,减小晶片表面材料去除非均匀性对确保半导体器件的高性能和稳定性至关重要。本文介绍了碳化硅材料的性质及应用与化学机械抛光工艺,研究了不同碳化硅化学机械抛光技术的材料去除机理、不同化学机械抛光技术的发展状况和性能及优缺点,综述了碳化硅晶片化学机械抛光中材料去除非均匀性影响因素,如:抛光压力、抛光液(磨粒)和转速等因素,最后对未来碳化硅化学机械抛光中材料去除非均匀性研究做出了展望。

关键词：碳化硅化学机械抛光材料去除抛光压力抛光液抛光垫

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Loading rate and holding load dependent room temperature nanoindentation creep behavior of 60NiTi alloy:Individual and coupling effects

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Journal of Materials Science & Technology 2022年第6期101卷 173-186页

作者： Wanjun He qunfeng zeng Chao Yan Jianing Zhu Danli Zhang Jiangnan Cao Institute of Design Science and Basic Components School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an 710049China Centre for Advancing Materials Performance from the Nanoscale State Key Laboratory for Mechanical Behaviour of MaterialsXi’an Jiaotong UniversityXi’an 710049China

60NiTi alloy is highly promising for aerospace bearings and *** load that is inevitably generated during launching process brings about an quick loading process and transient load duration,and may further results in an unnoticed but detrimental creep *** this account,the nanoindentation creep behavior of solution-treated 60NiTi alloy at room temperature and the corresponding influencing mechanism were *** results show that creep displacement was dominated by strain rate at the very beginning of holding *** rate and flow stress at the very beginning of holding stage were increased with an increased loading rate but declined with increasing holding load or with simultaneously increasing loading rate and holding *** underlying mechanisms were provided as nucleation and absorption of geometrically necessary dislocations(GNDs)associated with strain gradient plasticity theory rather than the model based on the consumption of creep deformation at loading stage.

关键词： Solution treated 60NiTi alloy Nanoindentation creep Strain rate Flow stress Dislocations

Enhanced micro/nano-tribological performance in partially crystallized 60NiTi film

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Friction 2021年第6期9卷 1635-1647页

作者： Wanjun HE qunfeng zeng Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System Xi’an Jiaotong UniversityXi’an 710049China

The microstructure,mechanical and micro/nano-tribological properties of the 60NiTi film annealed at different temperature were *** results reveal that annealing as-deposited 60NiTi film at 300,375,and 600℃ for 1 h leads to structural relaxation,partial crystallization and full crystallization,*** with the structurally relaxed structure,the partially crystallized structure exhibits increased hardness but decreased elastic *** is because that the elastic modulus is reduced by Voigt model while the hardness is improved by composite *** to the highest hardness and ratio of hardness to elastic modulus(H/E),the partially crystallized 60NiTi film has the lowest penetration depth and residual depth(i.e.,groove depth).Besides,the results also reveal that ductile plowing is the dominant wear mechanism for all the annealed 60NiTi *** the condition of the ductile plowing,coefficient of friction and wear resistance are related to penetration depth and residual depth,***,the partially crystallized 60NiTi film shows the best tribological performance at the micro/*** current work not only highlights the important roles of hardness and H/E in improving the micro/nano-tribological properties but also concludes an efficient and simple method for simultaneously increasing hardness and H/E.

关键词： 60NiTi film partial crystallization micro/nano-friction hardness ratio of hardness to elastic modulus

表面织构-活性屏离子氮化复合处理对38CrMoAl钢摩擦学行为的影响

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太原理工大学学报 2024年第3期55卷 483-492页

作者：王杰陈伟敬林乃明王强王焕焕袁烁刘志奇曾群锋吴玉程太原理工大学材料科学与工程学院太原030024 太重集团榆次液压工业有限公司山西晋中030621 太原科技大学机械工程学院太原030024 西安交通大学现代设计及转子轴承系统教育部实验室西安710049 合肥工业大学有色金属与加工技术国家地方联合工程研究中心合肥230009

【目的】38CrMoAl钢是液压泵柱塞常用材质之一,其表面性能对液压泵长寿命安全服役尤为重要。磨损是液压泵柱塞的主要失效方式,采用表面强化处理能够突破其性能极限,是实现液压泵高性能、高可靠运行的有效途径。【方法】采用表面织构化... 详细信息

【目的】38CrMoAl钢是液压泵柱塞常用材质之一,其表面性能对液压泵长寿命安全服役尤为重要。磨损是液压泵柱塞的主要失效方式,采用表面强化处理能够突破其性能极限,是实现液压泵高性能、高可靠运行的有效途径。【方法】采用表面织构化和活性屏离子氮化的复合处理工艺对38CrMoAl钢进行表面形性调控,以期实现其表面强化方法。先利用激光加工技术在38CrMoAl钢表面制备凹坑织构,再对38CrMoAl钢和表面织构化38CrMoAl钢进行活性屏离子氮化处理。借助球-盘式摩擦磨损试验机研究表面织构-活性屏离子氮化复合处理对38CrMoAl钢摩擦学行为的影响。【结果】结果表明,38CrMoAl钢表面生成了ε-Fe2-3N、γ'-Fe4N和CrN;氮化层表面致密且无明显裂纹和孔洞;氮化层均匀、连续,由白亮层和扩散层组成。氮化层的截面硬度呈梯度分布,试样表面硬度最高,随着距表面距离的增大,硬度逐渐降低。38CrMoAl钢相关试样与Al_(2)O_(3)球的干滑动摩擦结果可知,38CrMoAl钢的摩擦系数为0.40,而表面织构-活性屏离子氮化38CrMoAl钢的摩擦系数为0.36;经复合处理后,38CrMoAl钢的磨损失重降低了92.5%.复合处理显著提高了38CrMoAl钢的摩擦学性能。

关键词：表面织构活性屏离子氮化复合处理 38CrMoAl钢摩擦学性能

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火箭橇滑块高速重载磨损行为的研究进展

航空科学技术 2024年第4期35卷 1-8页

作者：李小凯严凯吴琳林乃明王振霞王玮华曾群锋吴玉程太原理工大学山西太原030024 航空工业航宇救生装备有限公司湖北襄阳441003 西安交通大学陕西西安710049 合肥工业大学安徽合肥230009

火箭橇试验是高超声速技术领域的技术基础,已成为世界范围内高端装备博弈的热点之一,开展火箭橇系统的运维与损伤控制研究尤为重要。作为火箭橇与火箭滑轨连接的纽带,滑块是火箭橇试验在高速重载工况下可靠服役的关键。火箭橇滑块在特... 详细信息

火箭橇试验是高超声速技术领域的技术基础,已成为世界范围内高端装备博弈的热点之一,开展火箭橇系统的运维与损伤控制研究尤为重要。作为火箭橇与火箭滑轨连接的纽带,滑块是火箭橇试验在高速重载工况下可靠服役的关键。火箭橇滑块在特定服役工况下的磨损,威胁着火箭橇试验系统的可靠运行和长寿命服役安全,更是制约火箭橇发展和应用的主要技术瓶颈。因此,开展火箭橇滑块高速重载磨损行为研究具有重要的理论价值和工程意义。本文首先介绍了国内外火箭橇试验系统的发展沿革与现状;进而,基于试验、模拟仿真、试验与模拟仿真结合,综述了火箭橇滑块高速重载磨损行为的研究进展。最后,着眼于模拟手段、高性能新型金属材料设计与制备、表面防护涂层等展望了解决火箭橇滑块磨损的可行途径,旨在为极端工况下材料服役损伤行为与控制技术提供借鉴与参考。

关键词：火箭橇滑块高速重载磨损行为

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工业机器人用RV减速器的齿廓动态磨损特性

华南理工大学学报（自然科学版） 2023年第1期51卷 22-30页

作者：周建星张荣华曾群锋崔权维新疆大学机械工程学院新疆乌鲁木齐830047 西安交通大学现代设计及转子轴承系统教育部重点实验室陕西西安710049

针对工业机器人用精密RV减速器齿廓动态磨损难以准确预测的问题,以BX-40E减速器为实例,基于广义Archard磨损公式,通过等效实验求得不同位置条件下减速器的磨损系数,并在磨损预测过程中考虑磨损演化后不同位置条件变化的影响。根据变形... 详细信息

针对工业机器人用精密RV减速器齿廓动态磨损难以准确预测的问题,以BX-40E减速器为实例,基于广义Archard磨损公式,通过等效实验求得不同位置条件下减速器的磨损系数,并在磨损预测过程中考虑磨损演化后不同位置条件变化的影响。根据变形协调理论和Langkali-Nikraves接触力模型确定齿间载荷分配与接触压力,考虑时变齿廓磨损与啮合力激励,采用解析建模方法建立了传动系统齿廓动态磨损数值计算模型。对比磨损系数取定值的齿廓磨损曲线,磨损数值与齿面分布规律均存在显著差异,整体差异随磨损次数增加而加剧,得出考虑接触位置条件差异的磨损系数对齿面磨损量化的准确性与必要性。摆线轮、针齿轮的齿面磨损深度曲线沿齿廓呈非对称不规则的倒“W”形,靠近齿根齿顶的部分因磨损而率先脱齿后再啮合,造成冲击,从而出现微突峰。在摆线齿廓凹凸过渡位置几乎不发生磨损。随磨损次数增加磨损峰峰域变窄,磨损率增势非均匀减缓。啮合力与压力角之间成一次函数映射关系。文中研究结果可为提高摆线针齿轮的减磨减振性能提供理论基础。

关键词： RV减速器磨损系数摆线针齿轮齿廓动态磨损 Langkali-Nikraves接触模型

我国技能型劳动者职业演进政策的时空特征分析

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教育与职业 2023年第8期1032卷 14-21页

作者：陈丽君曾群峰蔡治广东技术师范大学教育科学学院广东广州510665 广东邮电职业技术学院广东广州510630

技能型劳动者为国家建设提供重要的人才和技能支撑。提高技能型劳动者的职业发展空间,是建设技能型社会和培养高素质人才的关键。选取1978年以来51份相关政策文本,构建以共生理论的共生单元、基质和界面为空间维度,以技能型劳动者职业... 详细信息

技能型劳动者为国家建设提供重要的人才和技能支撑。提高技能型劳动者的职业发展空间,是建设技能型社会和培养高素质人才的关键。选取1978年以来51份相关政策文本,构建以共生理论的共生单元、基质和界面为空间维度,以技能型劳动者职业生涯演进阶段为时间维度的二维分析框架,运用Nvivo软件进行编码分析。研究发现,40余年来我国技能型劳动者职业演进政策经历了职业构建探索、职业培养转型、现代技术融合和职业生涯全面推进四个时期,存在共生空间分布均衡性不足、终身发展时间序列连贯性不强、职业演进时空协同效应不高等问题。建议加强共生界面与单元调控,优化职业发展共生空间;加强职后发展服务,完善时间连贯性强的终身技能教育体系;提高职业演进系统时空契合度,合力建设技能型社会。

关键词：技能型劳动者职业演进共生理论时空特征

Performance Deterioration Analysis of the Used Gear Oil

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Advances in Chemical Engineering and Science 2016年第2期6卷 67-75页

作者： qunfeng zeng Guangneng Dong Yanling Yang Tonghai Wu Key Laboratory of Ministry of Education for Modern Design and Rotor-Bearing System Xi’an Jiaotong University Xi’an China Jiangxi Key Laboratory of Advanced Copper and Tungsten Materials Jiangxi Academy of Science Nanchang China

In the present paper, we have investigated the tribological properties and microstructure of the used gear oil theoretically and experimentally. The deterioration process of the in-service gear lubricant oils was also discussed. The viscosity and microstructure of oils running different mileages were analyzed by viscometer and Fourier Transform Infrared Spectroscopy (FTIR), respectively. In addition, the friction and wear behaviors of the friction pair of the GCr15 steel ball and disc were investigated using a ball on disc tribometer under different mileages’ gear oils lubrication conditions. These techniques give reproducible and reliable data with which to evaluate the severity of deterioration process of oils. The objective of this work is to understand the deterioration process of gear oil and analyze the influence of deterioration on the performance and microstructure of lubricant oils used in gear box. Possible explanations of deterioration process as well as its influence on friction and wear behaviors are also discussed. The results reveals the tribological properties of used oils depended on strongly the microstructure and its deterioration process of oil.

关键词： Used Gear Oil Tribological Properties Viscosity FTIR Deterioration

Numerical Investigation on Flow Pattern of Air-Oil with Different Viscosities Lubrication

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Engineering（科研） 2017年第1期9卷 1-13页

作者： qunfeng zeng Jinhua Zhang Jun Hong Wenjun Su Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System and Fuli School of Food Equipment Engineering and Science Xi’an Jiaotong University Xi’an China State Key Laboratory for Manufacturing Systems Engineering Xi’an Jiaotong University Xi’an China

In the present work, the performance of oil-air two-phase flow under different lubricant oils was investigated. The simulation method was applied to study the influence of the oil viscosity on the flow pattern, velocity distribution and Re number in oil-air lubrication by FLUENT software with VOF model to acquire the working performance of oil-air lubrication for high-speed ball bearing. This method was used to obtain the optimum lubrication conditions of high-speed ball bearing. The optimum operating conditions that produce the optimum flow pattern were provided. The optimum annular flow was obtained by PAO6 oil with the low viscosity. Reynolds number influences the fluid shape and distribution of oil and air in pipe. The annular flow can be formed when Reynolds number is an appropriate value. The velocity distribution of oil-air two-phase flow at outlet was also discussed by different oil viscosities. The simulating results show that due to the effect of the oil viscosity and flow pattern the velocity decreased and expanded gradually close to the pipe wall, and the velocity increased close to the central pipe. The simulation results provide the proposal for the design and operation of oil-air two-phase flow lubrication experiments in the present work. This work provides a useful method in designing oil-air lubrication with the optimum flow pattern and the optimum operating conditions.

关键词： Oil-Air Lubrication Flow Pattern Two-Phase Flow Annular Flow