资源类型

期刊论文 358

会议视频 6

年份

2024 2

2023 24

2022 21

2021 25

2020 19

2019 13

2018 21

2017 22

2016 10

2015 12

2014 15

2013 21

2012 16

2011 15

2010 19

2009 20

2008 33

2007 25

2006 5

2005 2

展开 ︾

关键词

城市河流 2

微反应器 2

数值模拟 2

碳中和 2

360°表征 1

ADV 1

CCUS 1

CFD 1

CO2利用 1

Cas12a 1

Chebyshev多项式 1

Colebrook隐式方程 1

HY-2 卫星 1

Mallat算法 1

Matlab 1

Meyer小波变换 1

PIV 1

Preissmann格式 1

S 特性 1

展开 ︾

检索范围:

排序: 展示方式:

Simulation of abrasive flow machining process for 2D and 3D mixture models

Rupalika DASH,Kalipada MAITY

《机械工程前沿(英文)》 2015年 第10卷 第4期   页码 424-432 doi: 10.1007/s11465-015-0366-6

摘要:

Improvement of surface finish and material removal has been quite a challenge in a finishing operation such as abrasive flow machining (AFM). Factors that affect the surface finish and material removal are media viscosity, extrusion pressure, piston velocity, and particle size in abrasive flow machining process. Performing experiments for all the parameters and accurately obtaining an optimized parameter in a short time are difficult to accomplish because the operation requires a precise finish. Computational fluid dynamics (CFD) simulation was employed to accurately determine optimum parameters. In the current work, a 2D model was designed, and the flow analysis, force calculation, and material removal prediction were performed and compared with the available experimental data. Another 3D model for a swaging die finishing using AFM was simulated at different viscosities of the media to study the effects on the controlling parameters. A CFD simulation was performed by using commercially available ANSYS FLUENT. Two phases were considered for the flow analysis, and multiphase mixture model was taken into account. The fluid was considered to be a Newtonian fluid and the flow laminar with no wall slip.

关键词: abrasive flow machining (AFM)     computational fluid dynamics (CFD) modeling     mixture model    

Depth of cut models for multipass abrasive waterjet cutting of alumina ceramics with nozzle oscillation

Jun WANG

《机械工程前沿(英文)》 2010年 第5卷 第1期   页码 19-32 doi: 10.1007/s11465-009-0082-1

摘要: An experimental study of the depth of cut in multipass abrasive waterjet (AWJ) cutting of alumina ceramics with controlled nozzle oscillation is presented. It is found that this cutting technique can significantly increase the depth of cut by an average of 50.8% as compared to single pass cutting without nozzle oscillation under the corresponding cutting conditions and within the same cutting time. Predictive models for the depth of cut are then developed. The modelling process starts with single pass cutting using a dimensional analysis technique and the particle erosion theories applied to alumina ceramics, before progressing to the development of the models for multipass cutting. The models are finally assessed both qualitatively and quantitatively with experimental data. It is shown that the model predictions are in good agreement with the experimental data with the average deviations of about 1%.

关键词: abrasive waterjet     engineering ceramics     depth of cut     cutting performance     nozzle oscillation     machining    

游离磨料多股线线锯切割实验研究

王金生,姚春燕,彭伟,金鑫, 陈世杰

《中国工程科学》 2012年 第14卷 第11期   页码 94-98

摘要:

游离磨料线锯切割是将磨浆中的磨粒通过一定速度的细钢丝线带入切割区域,达到去除工件材料的目的。多股线由多根细金属线绕制而成,表面具有很多凹槽,与钢丝线光滑表面相比,可以输送更多的磨粒进入切割区域,从而提高切割效率。应用0.25 mm的多股线和0.25 mm的钢丝线对光学玻璃K9进行切割对比实验,结果表明,在相同工艺条件下,多股线的切割效率和表面粗糙度均优于钢丝线,但切缝宽度大于钢丝线。

关键词: 线锯     游离磨料加工     切割效率    

Effects of process parameters on surface roughness in abrasive waterjet cutting of aluminium

M. CHITHIRAI PON SELVAN, N. MOHANA SUNDARA RAJU, H. K. SACHIDANANDA

《机械工程前沿(英文)》 2012年 第7卷 第4期   页码 439-444 doi: 10.1007/s11465-012-0337-0

摘要:

Abrasive waterjet cutting is a novel machining process capable of processing wide range of hard-to-cut materials. Surface roughness of machined parts is one of the major machining characteristics that play an important role in determining the quality of engineering components. This paper shows the influence of process parameters on surface roughness (Ra) which is an important cutting performance measure in abrasive waterjet cutting of aluminium. Taguchi’s design of experiments was carried out in order to collect surface roughness values. Experiments were conducted in varying water pressure, nozzle traverse speed, abrasive mass flow rate and standoff distance for cutting aluminium using abrasive waterjet cutting process. The effects of these parameters on surface roughness have been studied based on the experimental results.

关键词: abrasive waterjet     aluminium     garnet     water pressure     mass flow rate     traverse speed     standoff distance    

Ultra-precision ductile grinding of BK7 using super abrasive diamond wheel

ZHAO Qingliang, Brinksmeier Ekkard, Riemer Oltmann, Rickens Kai

《机械工程前沿(英文)》 2007年 第2卷 第3期   页码 350-355 doi: 10.1007/s11465-007-0061-3

摘要: In this paper, a novel conditioning technique using copper bonded diamond grinding wheels of 91 yD grain size and electrolytic in-process dressing (ELID) is first developed to precisely and effectively condition a nickel-electroplated monolayer coarse-grained diamond grinding wheel of 151 μm grain size. Under optimised conditioning parameters, the super abrasive diamond wheel was well conditioned in terms of a minimized run-out error and flattened diamond grain surfaces of constant peripheral envelope. The conditioning force was monitored by a force transducer, while the modified wheel surface status was in-situ monitored by a coaxial optical distance measurement system. Finally, the grinding experiment on BK7 was conducted using the well-conditioned wheel with the corresponding surface morphology and subsurface damage measured by atomic force microscope (AFM) and scanning electric microscope (SEM), respectively. The experimental result shows that the newly developed conditioning technique is applicable and feasible to ductile grinding optical glass featuring nano scale surface roughness, indicating the potential of super abrasive diamond wheels in ductile machining brittle materials.

关键词: ELID     peripheral     electrolytic in-process     nickel-electroplated monolayer     measurement    

Molecular dynamics modeling of a single diamond abrasive grain in grinding

Angelos P. MARKOPOULOS,Ioannis K. SAVVOPOULOS,Nikolaos E. KARKALOS,Dimitrios E. MANOLAKOS

《机械工程前沿(英文)》 2015年 第10卷 第2期   页码 168-175 doi: 10.1007/s11465-015-0337-y

摘要:

In this paper the nano-metric simulation of grinding of copper with diamond abrasive grains, using the molecular dynamics (MD) method, is considered. An MD model of nano-scale grinding, where a single diamond abrasive grain performs cutting of a copper workpiece, is presented. The Morse potential function is used to simulate the interactions between the atoms involved in the procedure. In the proposed model, the abrasive grain follows a curved path with decreasing depth of cut within the workpiece to simulate the actual material removal process. Three different initial depths of cut, namely 4 ?, 8 ? and 12 ?, are tested, and the influence of the depth of cut on chip formation, cutting forces and workpiece temperatures are thoroughly investigated. The simulation results indicate that with the increase of the initial depth of cut, average cutting forces also increase and therefore the temperatures on the machined surface and within the workpiece increase as well. Furthermore, the effects of the different values of the simulation variables on the chip formation mechanism are studied and discussed. With the appropriate modifications, the proposed model can be used for the simulation of various nano-machining processes and operations, in which continuum mechanics cannot be applied or experimental techniques are subjected to limitations.

关键词: molecular dynamics     abrasive process     chip formation     cutting force     temperature    

Equipment–process–strategy integration for sustainable machining: a review

《机械工程前沿(英文)》 2023年 第18卷 第3期 doi: 10.1007/s11465-023-0752-4

摘要: Although the manufacturing industry has improved the quality of processing, optimization and upgrading must be performed to meet the requirements of global sustainable development. Sustainable production is considered to be a favorable strategy for achieving machining upgrades characterized by high quality, high efficiency, energy savings, and emission reduction. Sustainable production has aroused widespread interest, but only a few scholars have studied the sustainability of machining from multiple dimensions. The sustainability of machining must be investigated multidimensionally and accurately. Thus, this study explores the sustainability of machining from the aspects of equipment, process, and strategy. In particular, the equipment, process, and strategy of sustainable machining are systematically analyzed and integrated into a research framework. Then, this study analyzes sustainable machining-oriented machining equipment from the aspects of machine tools, cutting tools, and materials such as cutting fluid. Machining processes are explored as important links of sustainable machining from the aspects of dry cutting, microlubrication, microcutting, low-temperature cutting, and multidirectional cutting. The strategies for sustainable machining are also analyzed from the aspects of energy-saving control, machining simulation, and process optimization of machine tools. Finally, opportunities and challenges, including policies and regulations toward sustainable machining, are discussed. This study is expected to offer prospects for sustainable machining development and strategies for implementing sustainable machining.

关键词: sustainable machining     equipment     process     strategy     manufacturing    

Energy saving design of the machining unit of hobbing machine tool with integrated optimization

《机械工程前沿(英文)》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0694-2

摘要: The machining unit of hobbing machine tool accounts for a large portion of the energy consumption during the operating phase. The optimization design is a practical means of energy saving and can reduce energy consumption essentially. However, this issue has rarely been discussed in depth in previous research. A comprehensive function of energy consumption of the machining unit is built to address this problem. Surrogate models are established by using effective fitting methods. An integrated optimization model for reducing tool displacement and energy consumption is developed on the basis of the energy consumption function and surrogate models, and the parameters of the motor and structure are considered simultaneously. Results show that the energy consumption and tool displacement of the machining unit are reduced, indicating that energy saving is achieved and the machining accuracy is guaranteed. The influence of optimization variables on the objectives is analyzed to inform the design.

关键词: energy saving design     energy consumption     machining unit     integrated optimization     machine tool    

Fixturing technology and system for thin-walled parts machining: a review

《机械工程前沿(英文)》 2022年 第17卷 第4期 doi: 10.1007/s11465-022-0711-5

摘要: During the overall processing of thin-walled parts (TWPs), the guaranteed capability of the machining process and quality is determined by fixtures. Therefore, reliable fixtures suitable for the structure and machining process of TWP are essential. In this review, the key role of fixtures in the manufacturing system is initially discussed. The main problems in machining and workholding due to the characteristics of TWP are then analyzed in detail. Afterward, the definition of TWP fixtures is reinterpreted from narrow and broad perspectives. Fixture functions corresponding to the issues of machining and workholding are then clearly stated. Fixture categories are classified systematically according to previous research achievements, and the operation mode, functional characteristics, and structure of each fixture are comprehensively described. The function and execution mode of TWP fixtures are then systematically summarized and analyzed, and the functions of various TWP fixtures are evaluated. Some directions for future research on TWP fixtures technology are also proposed. The main purpose of this review is to provide some reference and guidance for scholars to examine TWP fixtures.

关键词: thin-walled part (TWP)     fixture     machining     fixture categories     fixture function    

Recent advances in micro- and nano-machining technologies

Shang GAO, Han HUANG

《机械工程前沿(英文)》 2017年 第12卷 第1期   页码 18-32 doi: 10.1007/s11465-017-0410-9

摘要:

Device miniaturization is an emerging advanced technology in the 21st century. The miniaturization of devices in different fields requires production of micro- and nano-scale components. The features of these components range from the sub-micron to a few hundred microns with high tolerance to many engineering materials. These fields mainly include optics, electronics, medicine, bio-technology, communications, and avionics. This paper reviewed the recent advances in micro- and nano-machining technologies, including micro-cutting, micro-electrical-discharge machining, laser micro-machining, and focused ion beam machining. The four machining technologies were also compared in terms of machining efficiency, workpiece materials being machined, minimum feature size, maximum aspect ratio, and surface finish.

关键词: micro machining     cutting     electro discharge machining (EDM)     laser machining     focused ion beam (FIB)    

采矿过程中磨料水射流性能通用预测方法

Eugene Averin

《工程(英文)》 2017年 第3卷 第6期   页码 888-891 doi: 10.1016/j.eng.2017.12.004

摘要:
极端采矿条件下的硬岩破碎可采用磨料水射流(AWJ)技术,这种技术能够在不产生粉尘的条件下有效切割难以机械加工的材料。这种技术还可用于爆破、本安和消防安全。就断裂力学而言,每一种可被破坏的材料均可被视为韧性或脆性材料。因此,需要找到一种无论使用AWJ 对何种材料进行切割都能精确预测其效率的方法。该问题可通过能量守恒法加以解决,它显示了材料去除量与AWJ 动能之间的比例。本文介绍了基于能量守恒法的预测方法,并提出如何达到最有效破坏水平的建议,以及关于涉及磨料流量与水流量、靶距和磨料颗粒粒径关系值的合理范围的建议。本文还提供了基于断裂力学的临时结构法确定材料破坏起始阈值条件的参数。

关键词: 磨料水射流     能量守恒法     切割深度     断裂力学     阈值速度     采矿    

Nanoparticle-enhanced coolants in machining: mechanism, application, and prospects

《机械工程前沿(英文)》 2023年 第18卷 第4期 doi: 10.1007/s11465-023-0769-8

摘要: Nanoparticle-enhanced coolants (NPECs) are increasingly used in minimum quantity lubrication (MQL) machining as a green lubricant to replace conventional cutting fluids to meet the urgent need for carbon emissions and achieve sustainable manufacturing. However, the thermophysical properties of NPEC during processing remain unclear, making it difficult to provide precise guidance and selection principles for industrial applications. Therefore, this paper reviews the action mechanism, processing properties, and future development directions of NPEC. First, the laws of influence of nano-enhanced phases and base fluids on the processing performance are revealed, and the dispersion stabilization mechanism of NPEC in the preparation process is elaborated. Then, the unique molecular structure and physical properties of NPECs are combined to elucidate their unique mechanisms of heat transfer, penetration, and anti-friction effects. Furthermore, the effect of NPECs is investigated on the basis of their excellent lubricating and cooling properties by comprehensively and quantitatively evaluating the material removal characteristics during machining in turning, milling, and grinding applications. Results showed that turning of Ti‒6Al‒4V with multi-walled carbon nanotube NPECs with a volume fraction of 0.2% resulted in a 34% reduction in tool wear, an average decrease in cutting force of 28%, and a 7% decrease in surface roughness Ra, compared with the conventional flood process. Finally, research gaps and future directions for further applications of NPECs in the industry are presented.

关键词: nanoparticle-enhanced coolant     minimum quantity lubrication     biolubricant     thermophysical properties     turning     milling     grinding    

role of cholesterol in modulation of morphology and mechanical properties of CHO-K1 cells: An in situ AFM

Lei Zhang, Lisha Zhao, Ping-Kai Ouyang, Pu Chen

《化学科学与工程前沿(英文)》 2019年 第13卷 第1期   页码 98-107 doi: 10.1007/s11705-018-1775-y

摘要:

Cholesterol plays a significant role in the organization of lipids and modulation of membrane dynamics in mammalian cells. However, the effect of cholesterol depletion on the eukaryotic cell membranes seems controversial. In this study, the effects of cholesterol on the topography and mechanical behaviors of CHO-K1 cells with manipulated membrane cholesterol contents were investigated by atomic force microscopy (AFM) technique. Here, we found that the depletion of cholesterol in cell membranes could increase the membrane stiffness, reduce the cell height as well as promote cell retraction and detachment from the surface, whereas the cholesterol restoration could reverse the effect of cholesterol depletion on the membrane stiffness. Increased methyl-β-cyclodextrin levels and incubation time could significantly increase Young’s modulus and degree of stiffing on cell membrane and cytoskeleton. This research demonstratede importance of cholesterol in regulating the dynamics of cytoskeleton-mediated processes. AFM technique offers excellent advantages in the dynamic monitoring of the change in membranes mechanical properties and behaviors during the imaging process. This promising technology can be utilized in studying the membrane properties and elucidating the underlying mechanism of distinct cells in the near-native environment.

关键词: cholesterol     methyl-β-cyclodextrin     atomic force microscopy     Young’s modulus     CHO-K1 cell    

A review of low-temperature plasma-assisted machining: from mechanism to application

《机械工程前沿(英文)》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0734-y

摘要: Materials with high hardness, strength or plasticity have been widely used in the fields of aviation, aerospace, and military, among others. However, the poor machinability of these materials leads to large cutting forces, high cutting temperatures, serious tool wear, and chip adhesion, which affect machining quality. Low-temperature plasma contains a variety of active particles and can effectively adjust material properties, including hardness, strength, ductility, and wettability, significantly improving material machinability. In this paper, we first discuss the mechanisms and applications of low-temperature plasma-assisted machining. After introducing the characteristics, classifications, and action mechanisms of the low-temperature plasma, we describe the effects of the low-temperature plasma on different machining processes of various difficult-to-cut materials. The low-temperature plasma can be classified as hot plasma and cold plasma according to the different equilibrium states. Hot plasma improves material machinability via the thermal softening effect induced by the high temperature, whereas the main mechanisms of the cold plasma can be summarized as chemical reactions to reduce material hardness, the hydrophilization effect to improve surface wettability, and the Rehbinder effect to promote fracture. In addition, hybrid machining methods combining the merits of the low-temperature plasma and other energy fields like ultrasonic vibration, liquid nitrogen, and minimum quantity lubrication are also described and analyzed. Finally, the promising development trends of low-temperature plasma-assisted machining are presented, which include more precise control of the heat-affected zone in hot plasma-assisted machining, cold plasma-assisted polishing of metal materials, and further investigations on the reaction mechanisms between the cold plasma and other materials.

关键词: low-temperature plasma     difficult-to-cut material     machinability     hydrophilization effect     Rehbinder effect    

Cryogenic minimum quantity lubrication machining: from mechanism to application

《机械工程前沿(英文)》 2021年 第16卷 第4期   页码 649-697 doi: 10.1007/s11465-021-0654-2

摘要: Cutting fluid plays a cooling–lubrication role in the cutting of metal materials. However, the substantial usage of cutting fluid in traditional flood machining seriously pollutes the environment and threatens the health of workers. Environmental machining technologies, such as dry cutting, minimum quantity lubrication (MQL), and cryogenic cooling technology, have been used as substitute for flood machining. However, the insufficient cooling capacity of MQL with normal-temperature compressed gas and the lack of lubricating performance of cryogenic cooling technology limit their industrial application. The technical bottleneck of mechanical–thermal damage of difficult-to-cut materials in aerospace and other fields can be solved by combining cryogenic medium and MQL. The latest progress of cryogenic minimum quantity lubrication (CMQL) technology is reviewed in this paper, and the key scientific issues in the research achievements of CMQL are clarified. First, the application forms and process characteristics of CMQL devices in turning, milling, and grinding are systematically summarized from traditional settings to innovative design. Second, the cooling–lubrication mechanism of CMQL and its influence mechanism on material hardness, cutting force, tool wear, and workpiece surface quality in cutting are extensively revealed. The effects of CMQL are systematically analyzed based on its mechanism and application form. Results show that the application effect of CMQL is better than that of cryogenic technology or MQL alone. Finally, the prospect, which provides basis and support for engineering application and development of CMQL technology, is introduced considering the limitations of CMQL.

关键词: cryogenic minimum quantity lubrication (CMQL)     cryogenic medium     processing mode     device application     mechanism     application effect    

标题 作者 时间 类型 操作

Simulation of abrasive flow machining process for 2D and 3D mixture models

Rupalika DASH,Kalipada MAITY

期刊论文

Depth of cut models for multipass abrasive waterjet cutting of alumina ceramics with nozzle oscillation

Jun WANG

期刊论文

游离磨料多股线线锯切割实验研究

王金生,姚春燕,彭伟,金鑫, 陈世杰

期刊论文

Effects of process parameters on surface roughness in abrasive waterjet cutting of aluminium

M. CHITHIRAI PON SELVAN, N. MOHANA SUNDARA RAJU, H. K. SACHIDANANDA

期刊论文

Ultra-precision ductile grinding of BK7 using super abrasive diamond wheel

ZHAO Qingliang, Brinksmeier Ekkard, Riemer Oltmann, Rickens Kai

期刊论文

Molecular dynamics modeling of a single diamond abrasive grain in grinding

Angelos P. MARKOPOULOS,Ioannis K. SAVVOPOULOS,Nikolaos E. KARKALOS,Dimitrios E. MANOLAKOS

期刊论文

Equipment–process–strategy integration for sustainable machining: a review

期刊论文

Energy saving design of the machining unit of hobbing machine tool with integrated optimization

期刊论文

Fixturing technology and system for thin-walled parts machining: a review

期刊论文

Recent advances in micro- and nano-machining technologies

Shang GAO, Han HUANG

期刊论文

采矿过程中磨料水射流性能通用预测方法

Eugene Averin

期刊论文

Nanoparticle-enhanced coolants in machining: mechanism, application, and prospects

期刊论文

role of cholesterol in modulation of morphology and mechanical properties of CHO-K1 cells: An in situ AFM

Lei Zhang, Lisha Zhao, Ping-Kai Ouyang, Pu Chen

期刊论文

A review of low-temperature plasma-assisted machining: from mechanism to application

期刊论文

Cryogenic minimum quantity lubrication machining: from mechanism to application

期刊论文