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

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Frontiers of Mechanical Engineering 2022年第4期17卷 1-32页

作者： Haibo LIU Chengxin WANG Te LI Qile BO Kuo LIU Yongqing WANG Key Laboratory for Precision and Non-traditional machining Technology of Ministry of Education Dalian University of TechnologyDalian 116024China

During the overall processing of thin-walled parts(TWPs),the guaranteed capability of the machining process and quality is determined by ***,reliable fixtures suitable for the structure and machining process of TWP are *** this review,the key role of fixtures in the manufacturing system is initially *** main problems in machining and workholding due to the characteristics of TWP are then analyzed in ***,the definition of TWP fixtures is reinterpreted from narrow and broad *** functions corresponding to the issues of machining and workholding are then clearly *** categories are classified systematically according to previous research achievements,and the operation mode,functional characteristics,and structure of each fixture are comprehensively *** function and execution mode of TWP fixtures are then systematically summarized and analyzed,and the functions of various TWP fixtures are *** directions for future research on TWP fixtures technology are also *** 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

Experimental Study on Entropy Features in machining Vibrations of A Thin-Walled Tubular Workpiece

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Journal of Dynamics, Monitoring and Diagnostics 2023年第1期2卷 61-68页

作者： Kaibo Lu Xin Wang Xun Chen Xinyu Pang Fengshou Gu College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyShanxi 030024China General Engineering Research Institute Liverpool John Moores UniversityLiverpoolL35UXUK School of Computing and Engineering University of HuddersfieldHuddersfieldHD13DHUK

In machining processes,chatter vibrations are always regarded as one of the major limitations for production quality and *** and timely monitoring of chatter is helpful to maintain stable machining *** present,most chatter monitoring methods are based on the energy level at specified chatter frequencies or frequency ***,the spectral features of chatter could change during machining operations due to complexity and time-varying dynamics of the physical machining *** purpose of this paper is to investigate the time-varying chatter features in turning of thin-walled tubular workpieces from the perspective of *** airborne acoustics was selected as the source of information for machining condition ***,corresponding to the distinguishing surface topographies relevant to machining conditions,the features of the sound signal emitted during turning of the thin-walled cylindrical workpieces were extracted using the spectral analysis and wavelet packet transform,*** was shown that the dominant vibration frequency as well as the energy distribution could shift with the transition of the machining *** that,two relative entropy indicators based on the spectrum and the wavelet packet energy were constructed to identify chattering events in turning of the thin-walled *** experimental results demonstrate that the proposed indicators could accurately reflect the transition of machining conditions with high sensitivity and robustness in comparison with the traditional FFT-based *** achievement of this study lays the foundations of the online chatter monitoring and control technique for turning of the thin-walled tubular workpieces.

关键词： machining chatter relative entropy thin-walled work pieces

machining of SiC ceramic matrix composites:A review

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Chinese Journal of Aeronautics 2021年第4期34卷 540-567页

作者： Qinglong AN Jie CHEN Weiwei MING Ming CHEN State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Continuous fiber reinforced SiC ceramic matrix composites(FRCMCs-SiC)are currently the preferred material for hot section components,safety–critical components and braking components(in the aerospace,energy,transportation)with high value,and have triggered the demand for ***,the high brittleness,anisotropy,and heterogeneity of materials bring great challenges to machining,due to high mechanical and thermal loads,severe tool wear,and poor machining *** the increasing demand of FRCMCs-SiC parts,high-quality and high-efficient machining has become a hot *** review paper provides a detailed literature survey on the machining of *** material removal mechanism,defect form,and interfacial mechanical properties of FRCMCs-SiC were *** machining processes of FRCMCs-SiC were introduced,and their respective advantages and disadvantages were *** the low machinability(high hardness,high brittleness,anisotropy,and heterogeneity)of FRCMCs-SiC,preliminary experiments have proved that ultrasonic-assisted machining and laser-assisted machining have shown unique advantages in reducing force and tool wear,improving machining quality and machining *** machined surface integrity was discussed,the influence of process parameters on the machined surface quality was analyzed,and the machining defects of FRCMCs-SiC were *** for FRCMCs-SiC,the existing quantitative evaluation of the machined surface integrity was weak and unsystematic.

关键词： Ceramic matrix composites machining Material removal mechanisms Quality Surface integrity

machining performance on hybrid process of abrasive jet machining and electrical discharge machining

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中国有色金属学会会刊：英文版 2012年第S3期22卷 775-780页

作者： Yan-cherng LIN Yuan-feng CHEN A-cheng WANG Wan-lin SEI Department of Mechanical Engineering Chien Hsin University of Science and Technology Department of Mechanical Engineering Nan Kai University of Technology

To develop a hybrid process of abrasive jet machining (AJM) and electrical discharge machining (EDM),the effects of the hybrid process parameters on machining performance were comprehensively investigated to confirm the benefits of this hybrid *** appropriate abrasives delivered by high speed gas media were incorporated with an EDM in gas system to construct the hybrid process of AJM and EDM,and then the high speed abrasives could impinge on the machined surface to remove the recast layer caused by EDM process to increase the efficiency of material removal and reduce the surface *** this study,the benefits of the hybrid process were determined as the machining performance of hybrid process was compared with that of the EDM in gas *** main process parameters were varied to explore their effects on material removal rate,surface roughness and surface *** experimental results show that the hybrid process of AJM and EDM can enhance the machining efficiency and improve the surface ***,the developed hybrid process can fit the requirements of modern manufacturing applications.

关键词： hybrid process electrical discharge machining abrasive jet machining EDM in gas surface roughness

machining characteristics of fine grained AZ91 Mg alloy processed by friction stir processing

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Transactions of Nonferrous Metals Society of China 2017年第4期27卷 804-811页

作者： G.V.V.SURYA KIRAN K.HARI KRISHNA Sk.SAMEER M.BHARGAVI B.SANTOSH KUMAR G.MOHANA RAO Y.NAIDUBABU RAVIKUMAR DUMPALA B.RATNA SUNIL Department of Mechanical Engineering Rajiv Gandhi University of Knowledge Technologies (AP-IIIT) Nuzvid 521202 India Department of Mechanical Engineering Visvesvaraya National Institute of Technology Nagpur 440010 India

AZ91Mg alloy was considered and friction stir processing(FSP)was adopted to achieve grain refinement to investigatethe effect of grain size and secondary phase on machining characteristics during drilling at various speeds and *** saturatedAZ91Mg alloy was obtained after FSP and the grain refinement was achieved from(166.5±8.7)μm to(21.7±13.5)μ***,hardness reduced for FSP AZ91Mg alloy(88.95±6.1)compared with AZ91alloy(108.2±15.6),which was attributed to the reducedsecondary ***,the mean cutting force for FSP-treated(FSPed)AZ91Mg alloy was marginally *** edgedamage of the drilled holes was lower for FSPed AZ91Mg alloy compared with unprocessed AZ91Mg ***,it can beunderstood that the grain refinement may slightly increase the cutting forces during drilling but better edge finishing can be achievedin machining of AZ91Mg alloy.

关键词： magnesium alloy friction stir processing machining grain size microstructure

machining Parameters Optimization of Multi-Pass Face Milling Using a Chaotic Imperialist Competitive Algorithm with an Efficient Constraint-Handling Mechanism

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Computer Modeling in Engineering & Sciences 2018年第9期116卷 365-389页

作者： Yang Yang College of Engineering Huazhong Agricultural UniversityKey Laboratory of Agricultural Equipment in Mid-lower Yangtze RiverMinistry of Agriculture430070WuhanChina

The selection of machining parameters directly affects the production time,quality,cost,and other process performance measures for multi-pass *** of machining parameters is of great ***,it is a nonlinear constrained optimization problem,which is very difficult to obtain satisfactory solutions by traditional optimization methods.A new optimization technique combined chaotic operator and imperialist competitive algorithm(ICA)is proposed to solve this *** ICA simulates the competition between the *** is a population-based meta-heuristic algorithm for unconstrained optimization *** development operator based on chaotic sequence is introduced to improve the local search of ICA,while constraints handling mechanism is introduced and an imperialist-colony transformation policy is *** improved ICA is called chaotic imperialist competitive algorithm(CICA).A case study of optimizing machining parameters for multi-pass face milling operations is presented to verify the effectiveness of the proposed *** case is to optimize parameters such as speed,feed,and depth of cut in each pass have yielded a minimum total product ion *** depth of cut of optimal strategy obtained by CICA are 4 mm,3 mm,1 mm for rough cutting pass 1,rough cutting pass 1 and finish cutting pass,*** cost for each pass are$0.5366 US,$0.4473 US and$0.3738 *** optimal solution of CICA for various strategies with at=8 mm is$1.3576 *** results obtained with the proposed schemes are better than those of previous *** shows the superior performance of CICA in solving such ***,optimization of cutting strategy when the width of workpiece no smaller than the diameter of cutter is *** can be drawn that larger tool diameter and row spacing should be chosen to increase cutting efficiency.

关键词： Chaotic imperialist competitive algorithm constraint-handling mechanism multi-pass face milling machining parameters optimization cutting strategy

Jerk-limited feedrate scheduling and optimization for five-axis machining using new piecewise linear programming approach

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Science China(Technological Sciences) 2019年第7期62卷 1067-1081页

作者： SUN YuWen CHEN ManSen JIA JinJie LEE Yuan-Shin GUO DongMing School of Mechanical Engineering Dalian University of Technology Dalian 116024 China Department of Industrial and Systems Engineering North Carolina State University Raleigh NC 27695 USA

In this paper, a new computation method and an optimization algorithm are presented for feedrate scheduling of five-axis machining in compliance with both machine drive limits and process limits. Five-axis machine tool with its ability of controlling tool orientation to follow the sculptured surface contour has been widely used in modern manufacturing industry. Feedrate scheduling serving as a kernel of CNC control system plays a critical role to ensure the required machining accuracy and reliability for five-axis machining. Due to the nonlinear coupling effects of all involved drive axes and the saturation limit of servo motors, the feedrate scheduling for multi-axis machining has long been recognized and remains as a critical challenge for achieving five-axis machine tools’ full capacity and advantage. To solve the nonlinearity nature of the five-axis feedrate scheduling problems, a relaxation mathematical process is presented for relaxing both the drive motors’ physical limitations and the kinematic constraints of five-axis tool motions. Based on the primary optimization variable of feedrate, the presented method analytically linearizes the machining-related constraints, in terms of the machines’ axis velocities, axis accelerations and axis jerks. The nonlinear multi-constrained feedrate scheduling problem is transformed into a manageable linear programming problem. An optimization algorithm is presented to find the optimal feedrate scheduling solution for the five-axis machining problems. Both computer implementation and laboratorial experiment testing by actual machine cutting were conducted and presented in this paper. The experiment results demonstrate that the proposed method can effectively generate efficient feedrate scheduling for five-axis machining with constraints of the machine tool physical constraints and limits. Compared with other existing numerical methods, the proposed method is able to find an accurate analytical solution for the nonlinear cons

关键词： five-axis machining feedrate scheduling jerk linear programming optimization

Methods for Integrating Energy Consumption and Environmental Impact Considerations into the Production Operation of machining Processes

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Chinese Journal of Mechanical Engineering 2010年第4期23卷 428-435页

作者： HE Yan LIU Fei State Key Laboratory of Mechanical Transmission Chongqing University Chongqing 400030 China

Energy consumption and environmental impact considerations of machining processes are viewed as important issues for the global trends towards sustainable manufacturing. The existing research of reducing energy consumption and environmental impacts of machining processes greatly focuses on design and planning activities, but is reasonably sparse for production operation activities. This paper explores a systematic methodology that incorporates energy consumption and environmental impact considerations into the production operation of machining processes. Firstly, the framework of the methodology is proposed to establish the generic procedures for integrating the above considerations in production operation activities. As the two key issues of the framework, the profile index value matrix is determined by valuing the individual quantity of energy consumption and environmental impacts of machining each job on each machine, and the multi-criteria models are constructed by the operational methods. Furthermore, with the guideline of the framework, the specific formulations are modeled by two sub-models for the parallel machine scheduling problem, in which makespan and energy consumption are the optimizing objectives as well as the constraints of environmental impact considerations. The specific formulations provide a practical method to integrate energy consumption and environmental impact considerations into the scheduling activity, and also can serve as a reference to other activities in the production operation. The case study for a batch of jobs, including seven kinds of gears in the machining shop floor, is presented to demonstrate the application of the specific formulations of the methodology. The proposed methodology provides potential opportunities for reducing energy consumption and environmental impacts in machining processes, and helps production managers in decision-making on the issues of energy consumption and environmental impacts in the production operat

关键词： green manufacturing energy environmental impact production operation machining

Constitutive Modeling for Ti-6Al-4V Alloy machining Based on the SHPB Tests and Simulation

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Chinese Journal of Mechanical Engineering 2016年第5期29卷 962-970页

作者： CHEN Guang KE Zhihong REN Chengzu LI Jun Key Laboratory of Equipment Design and Manufacturing Technology Tianjin University Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin University

A constitutive model is critical for the prediction accuracy of a metal cutting simulation. The highest strain rate involved in the cutting process can be in the range of 104-106 s 1. Flow stresses at high strain rates are close to that of cutting are difficult to test via experiments. Split Hopkinson compression bar （SHPB） technology is used to study the deformation behavior of Ti-6Al-4V alloy at strain rates of 10 -4-10 4s- 1. The Johnson Cook （JC） model was applied to characterize the flow stresses of the SHPB tests at various conditions. The parameters of the JC model are optimized by using a genetic algorithm technology. The JC plastic model and the energy density-based ductile failure criteria are adopted in the proposed SHPB finite element simulation model. The simulated flow stresses and the failure characteristics, such as the cracks along the adiabatic shear bands agree well with the experimental results. Afterwards, the SHPB simulation is used to simulate higher strain rate（approximately 3 × 10 4 s -1） conditions by minimizing the size of the specimen. The JC model parameters covering higher strain rate conditions which are close to the deformation condition in cutting were calculated based on the flow stresses obtained by using the SHPB tests （10 -4 - 10 4 s- 1） and simulation （up to 3 × 10 4 s - 1）. The cutting simulation using the constitutive parameters is validated by the measured forces and chip morphology. The constitutive model and parameters for high strain rate conditions that are identical to those of cutting were obtained based on the SHPB tests and simulation.

关键词： constitutive model Ti-6Al-4V alloy SHPB test high strain rate machining