共查询到20条相似文献,搜索用时 171 毫秒
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采用基于范数权重的灰关联度分析方法对高硅铝合金进行多目标优化试验分析。通过对各工艺指标灰关联系数的极差分析和主效应分析,研究了工件竖直超声振动加工中峰值电流、间隙电压、脉冲间隔、脉冲宽度对加工效率和加工精度的影响。使用范数的方法确定了各工艺指标的权重进而对综合工艺指标进行了优化,得到一组最优参数组合。试验验证结果表明,经过优化以后表面精度提高25.63%,加工时间减少了3.542%,优化组的综合指标灰关联度提高为0.732。 相似文献
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基于信噪比与灰关联度的电火花微小孔加工工艺参数的优化 总被引:12,自引:1,他引:11
在正交试验的基础上,采用参数设计中的信噪比方法,更加准确地反映具有强干扰特性的电火花微细加工过程中参数对加工工艺目标的影响程度,分析出各项参数对工艺指标影响的主次关系。以减小工艺性能的波动性为目的,结合灰色关联度分析方法,将多目标参数优化问题转化为单目标灰关联度的优化问题,得到电火花微小孔加工的多项工艺指标要求下的参数优化组合。综合试验结果表明,基于信噪比和灰关联度的优化方法能有效地提高微细电火花的加工精度、加工效率和加工稳定性。 相似文献
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针对钛合金的难加工特点,单纯EDM、ECM的局限性以及EDM和ECM串行加工的低效率问题,在低电阻去离子水中加入碳化硅磨粒,开展了磨粒辅助作用下的EDM和ECM并行复合加工.将材料去除率、电极损耗率和表面粗糙度作为评价指标,通过正交试验和灰关联度分析,将多工艺目标转化为单一评价指标,得到峰值电流、脉冲宽度、磨粒浓度和放电电压主要工艺参数的优化组合,并进行了试验验证.结果表明:峰值电流为1.5 A、脉冲宽度为30μs、磨料浓度为5 g/L、放电电压为40 V的工艺参数组合所得到的电极损耗率、表面粗糙度和表面形貌都得到明显改善. 相似文献
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《机械设计与制造》2017,(5)
针对磨加工主动量仪在高精密磨削加工中的工艺参数寻优问题,该文采用由正交试验方法得到工艺参数与评价指标的实验数据,基于灰色系统理论,通过对实验数据分析,提出由工艺参数与评价指标之间的灰色关联度得出工艺参数对评价指标的影响程度的方法,得出在该加工实验中,精磨加工余量对表面粗糙度和圆度的的影响最大,接着依次为粗磨加工余量、粗磨砂轮切入速度、光磨加工余量和精磨砂轮切入速度;提出由加权灰靶决策对评价指标分析决策找到试验工艺参数最优组合的方法,得出16组实验参数组合中最优组合。该研究成果可以分析工艺参数与评价指标的关联,进行工艺参数寻优,为磨加工主动量仪中的工艺参数设定和自主寻优程序设计提供理论方法,进而提高磨加工主动量仪的智能化水平。 相似文献
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为了研究电火花线切割工艺参数(脉冲宽度、脉冲间隔、峰值电流、极间电压)对TC4钛合金加工的影响规律,本文通过一组四因素四水平正交试验,以切割速度、加工精度作为评价指标,通过极差分析法研究各工艺参数对钛合金加工的影响程度.试验结果表明:脉冲宽度对切割速度的影响是最大的,峰值电流对加工精度的影响是最大的.在脉冲宽度为24μ... 相似文献
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Optimization of EDM process for multiple performance characteristics using Taguchi method and Grey relational analysis 总被引:1,自引:0,他引:1
Electrical discharge machining (EDM) is one of the most extensively used non-conventional material removal processes. The
Taguchi method has been utilized to determine the optimal EDM conditions in several industrial fields. The method, however,
was designed to optimize only a single performance characteristic. To remove that limitation, the Grey relational analysis
theory has been used to resolve the complicated interrelationships among the multiple performance characteristics. In the
present study, we attempted to find the optimal machining conditions under which the micro-hole can be formed to a minimum
diameter and a maximum aspect ratio. The Taguchi method was used to determine the relations between machining parameters and
process characteristics. It was found that electrode wear and the entrance and exit clearances had a significant effect on
the diameter of the micro-hole when the diameter of the electrode was identical. Grey relational analysis was used to determine
the optimal machining parameters, among which the input voltage and the capacitance were found to be the most significant.
The obtained optimal machining conditions were an input voltage of 60V, a capacitance of 680pF, a resistance of 500Ω, the
feed rate of 1.5μm/s and a spindle speed of 1500rpm. Under these conditions, a micro-hole of 40μm average diameter and 10
aspect ratio could be machined. 相似文献
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E. Aliakbari H. Baseri 《The International Journal of Advanced Manufacturing Technology》2012,62(9-12):1041-1053
Electrical discharge machining (EDM) is one of the advanced methods of machining. Most publications on the EDM process are directed towards non-rotational tools. But rotation of the tool provides a good flushing in the machining zone. In this study, the optimal setting of the process parameters on rotary EDM was determined. A total of three variables of peak current, pulse on time, and rotational speed of the tool with three types of electrode were considered as machining parameters. Then some experiments have been performed by using Taguchi's method to evaluate the effects of input parameters on material removal rate, electrode wear rate, surface roughness, and overcut. Moreover, the optimal setting of the parameters was determined through experiments planned, conducted, and analyzed using the Taguchi method. Results indicate that the model has an acceptable performance to optimize the rotary EDM process. 相似文献
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Optimization of machining parameters using magnetic-force-assisted EDM based on gray relational analysis 总被引:1,自引:1,他引:0
Yan-Cherng Lin Ho-Shiun Lee 《The International Journal of Advanced Manufacturing Technology》2009,42(11-12):1052-1064
This work developed a novel process of magnetic-force-assisted electrical discharge machining (EDM) and conducted an experimental investigation to optimize the machining parameters associated with multiple performance characteristics using gray relational analysis. The main machining parameters such as machining polarity (P), peak current (I P), pulse duration (τ P), high-voltage auxiliary current (I H), no-load voltage (V), and servo reference voltage (S V) were selected to explore the effects of multiple performance characteristics on the material removal rate, electrode wear rate, and surface roughness. The experiments were conducted according to an orthogonal array L18 based on Taguchi method, and the significant process parameters that affected the multiple performance characteristics of magnetic-force-assisted EDM were also determined form the analysis of variance. Moreover, the optimal combination levels of machining parameters were also determined from the response graph and then verified experimentally. The multiple performance characteristics of the magnetic-force-assisted EDM were improved, and the EDM technique with high efficiency, high precision, and high-quality surface were established to meet the demand of modern industrial applications. 相似文献
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《Measurement》2014
In this article a modified algorithm (grey based fuzzy algorithm) is used to optimize multiple performance characteristics in drilling of bone. Experiments have been performed with different cutting conditions using full factorial design. The quality parameters considered are temperature, force and surface roughness. Grey relational analysis (GRA) coupled with fuzzy logic is employed to obtain a grey fuzzy reasoning grade (GFRG) combining all the quality characteristics. The highest GFRG is obtained for the feed rate of 40 mm/min and the speed of 500 rpm and is the optimal level. Analysis of variance (ANOVA) carried out to find the significance of parameters on multiple performance characteristics revealed that the feed rate has the highest contribution on GFRG followed by the spindle speed. The optimum level of the process parameters obtained is validated by the confirmation experiment. 相似文献
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L. Selvarajan M. Manohar A. Udhaya kumar P. Dhinakaran 《Journal of Mechanical Science and Technology》2017,31(1):111-122
Electric discharge machining (EDM) is a highly promising machining process of ceramics. This research is an out of the paradigm investigation of EDM on Si3N4-TiN with Copper electrode. Ceramics are used for extrusion dies and bearing balls and they are more efficient, effective and even have longer life than conventional metal alloys. Owing to high hardness of ceramic composites, they are almost impossible to be machined by conventional machining as it entirely depends on relative hardness of tool with work piece. Whereas EDM offers easy machinability combined with exceptional surface finish. Input parameters of paramount significance such as current (I), pulse on (Pon) and off time (Poff), Dielectric pressure (DP) and gap voltage (SV) are studied using L25 orthogonal array. With help of mean effective plots the relationship of output parameters like Material removal rate (MRR), Tool wear rate (TWR), Surface roughness (Ra), Radial overcut (ROC), Taper angle (α), Circularity (CIR), Cylindricity (CYL) and Perpendicularity (PER) with the considered input parameters and their individual influence were investigated. The significant machining parameters were obtained by Analysis of variance (ANOVA) based on Grey relational analysis (GRA) and value of regression coefficient was determined for each model. The results were further evaluated by using confirmatory experiment which illustrated that spark eroding process could effectively be improved. 相似文献
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Study on the characteristics of plasma channel based on multi-spark pulse discharge machining effect
Yang Shen Jilun Chen Yiming Yang Kun Zhang Yong Li Bo Zhu 《The International Journal of Advanced Manufacturing Technology》2018,97(5-8):1745-1752
Plasma channel characteristics and energy distribution in electrical discharge machining (EDM) were mostly studied by analyzing the geometry parameters of craters caused by a single pulse discharge in previous studies. However, single pulse experiments cannot provide us insights into superposition, migration, abruption, interruption, and other phenomena of the plasma channel which have significant effects on EDM. Besides, EDM itself is a consecutive pulse discharge process. Thus, this paper focuses on the characteristics of plasma channel and the mechanism of material removal based on experimental data from multi-spark pulse discharge machining. The contrastive milling experiments of different parameters in multi-spark pulse discharge machining in high-speed dry EDM by using nickel-based superalloy as workpiece were conducted. The effects of peak current, dielectric type, breakdown voltage, air pressure, and electrode rotation speed on the crater number, crater distance, crater depth, and crater removal volume were studied. The plasma channel characteristics and material removal mechanism in continuous machining of high-speed dry EDM were revealed. 相似文献
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设计了以DSP和CPLD为控制单元的微细电火花脉冲电源,满足微细电火花加工单个脉冲能量小而可控的要求。针对加工过程难以用数学模型描述的问题,利用智能控制不依赖数学模型的优势,设计了模糊神经网络控制器,根据间隙放电状态,对在线参数实时调整。通过微小孔加工实验表明,采用智能控制的加工方式可以提高加工速度,有很好的应用前景。 相似文献
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采用紫铜工具电极,在峰值电流为4-24A、脉冲宽度为25-200μs、加工电压为80-200V的电参数范围内,综合应用因子试验和正交试验方法,对难加工材料4Cr5MoVSi进行了电火花加工试验。在进行电加工基础特征规律分析的基础上,考查了电参数对加工速度、双边侧面放电间隙、电极损耗的影响,并对电火花加工机理进行了分析。研究结果表明:采用紫铜电极电火花加工4Cr5MoVSi,在本试验范围内,峰值电流Ip与脉冲宽度ti、加工电压U、脉冲间隔t0存在一定的交互作用;与其它三个因素相比,峰值电流对加工速度、电极损耗、双边侧面放电间隙的影响更显著;随脉冲宽度和加工电压的增大,电极损耗逐渐减小。 相似文献
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S. Singh 《The International Journal of Advanced Manufacturing Technology》2012,63(9-12):1191-1202
Present investigation applied the designs of experiments and grey relational analysis (GRA) approach to optimise parameters for electrical discharge machining process of 6061Al/Al2O3p/20P aluminium metal matrix composites. Planning of experiments was based on an L18 (2^1?×?3^5) orthogonal array to determine an optimal setting. The process parameters included one noise factor, aspect ratio having two levels and five control factors, viz. pulse current, pulse ON time, duty cycle, gap voltage and tool electrode lift time with three levels each. The material removal rate, tool wear rate and surface roughness were selected as the evaluation criteria, in this study. Optimal combination of process parameters is determined by the grey relational grade (GRG) obtained through GRA for multiple performance characteristics. Analysis of variance for the GRG is also implemented. It is shown that through GRA, the optimization of the multiple performance characteristics can be greatly simplified. 相似文献
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This paper describes the development of parallel spark EDM method. In the discharge circuit, the electrode is divided into multiple electrodes, each of which is electrically insulated and connected to the pulse generator through a diode. A capacitor is inserted parallel to each discharge gap between each electrode and workpiece (here workpiece is common for each electrode). Compared with conventional EDM in which only a singular discharge can be generated for each pulse, multiple discharges can dispersively be generated for each pulse in parallel spark EDM. Results of experiments on parallel spark EDM and conventional EDM show that not only is the machining process more stable, but the machining speed and surface roughness can also be improved with parallel spark EDM. 相似文献