快走丝线切割加工精度和表面质量影响因素的分析

对影响快走丝线切割加工精度和表面质量的各种因素进行了分析,对各种影响因素不同的作用进行了阐述,总结了取得好的加工效果应采取的措施.     

多次切割技术在高速走丝线切割机的应用

针对传统高速走丝线切割机的加工表面质量和加工精度低的问题,利用慢走丝线切割机加工原理,采用多次切割加工技术,提升该类型线切割机水平.对多次切割工艺参数进行探讨,并在DK725、DK7740型高速走丝线切割机上进行实际加工效果对比,加工表面质量和加工精度有明显提高,同时分析和提出了精度保持性、加工效率还需进一步提高的现实问题.提出在优化设计机床结构、运丝系统、实时补偿和钼丝损耗等方面的改进思路.     

快走丝线切割加工质量的影响因素与解决措施

表面粗糙度是衡量电火花线切割加工性能的重要指标之一.文中从主要影响电火花线切割加工表面粗糙度的机械因素、脉冲参数、进给速度、工作液性能等方面分析原因,并提出提高高速走丝线切割加工工件表面质量的方法.为提高高速走丝切割加工表面质量提供了参考.     

快走丝线切割加工品质的影响因素及对策

分析快走丝线切割加工精度的影响因素,提出了提高加工精度的措施.     

快走丝线切割机厚大工件加工影响因素分析

快走丝线切割机在切割厚大工件时,易出现切割不稳定、短路及断丝等问题,通过在DK7732型快走丝线切割机上加工厚大工件试验,从电参数、切削液及运丝系统等方面进行综合分析,提出了加工厚大工件的工艺方法。     

高速走丝气中电火花线切割模具钢的研究

对高速走丝线切割机床进行了气中和液中的加工工艺对比分析。实验结果表明，采用气中切割加工工艺，可提高其加工工件的切割速度和表面质量。     

高速走丝线切割机床改造及多次切割加工试验研究

利用模具钢Cr12样件,用高速走丝线切割机床进行多次切割试验研究,结果表明,采用多次切割能提高切割精度和表面质量.同时提出高速走丝线切割机床进行多次切割工艺时存在的问题和前提条件,并阐述了多次切割的理想工艺参数.     

模具慢走丝线切割加工异常问题及分析

根据模具企业多年的慢走丝线切割加工实践经验,就慢走丝线切割加工效率、表面质量、加工精度3方面的异常问题,分析了其产生原因并提出了解决问题的具体措施,对提高慢走丝线切割加工质量有重要指导作用。     

快速走丝切割机床多次切割工艺及其对表面质量的影响

本文叙述了在国产快速走丝线切割机床上采用第一次电火花切割,第二次脉冲电解加工的工艺方法,使得工件的表面质量大为提高。讨论了具体的切割工艺并提出相应参数。     

钼丝使用寿命影响因素的分析及预防措施

从快走丝线切割加工中的加工材料处理、短路故障、操作规范、工作液性能等几方面分析了切割加工中影响钼丝使用寿命的一些不稳定加工状态和影响因素,提出了提高钼丝使用寿命的有效措施.     

DK7732型电火花线切割机加工技术的改进

通过对DK7732型电火花线切割机在使用中存在的问题进行分析,提出了解决方法,并针对所提出的解决方法进行了改进。改进后的DK7732型电火花线切割机在使用性能上有了很大的改进。此方法也可以作为DK7732型电火花线切割机生产厂家在进行此类型电火花线切割机生产时借鉴之用。     

新型中走丝线切割工作液的研制

根据中走丝电火花线切割加工的特点,研制出一种新型中走丝电火花线切割工作液。分析了中走丝电火花线切割工作液性能对加工的影响,探讨了工作液的组成和各种添加剂的选择。加工试验表明,研制的走丝电火花线切割工作液符合中走丝电火花线切割加工特性和防锈要求,能在高加工效率下加工得到较高表面质量的工件。     

Selection of optimal process parameters in WEDM while machining Al7075/SiCp metal matrix composites

Aluminium metal matrix composites (MMCs) reinforced with silicon carbide particulate (SiCp) find several applications due to their improved mechanical properties over the conventional metals for a wide variety of aerospace and automotive applications. However, the presence of discontinuously distributed hard ceramic in the MMCs made them as difficult-to-cut materials for conventional machining methods. The wire electrical discharge machining (WEDM), as a widely adopted non-traditional machining method for difficult-to-cut precision components, found an appropriate metal removal process for MMCs to enhance quality of cut within the stipulated cost. While machining the advanced materials like MMCs, a clear understanding into the machining performance of the process for its control variables could make the process uncomplicated and economical. In light of the growing industrial need of making high performance-low cost components, the investigation aimed to explore the machining performance characteristics of SiCp reinforced Al7075 matrix composites (Al7075/SiCp) during WEDM. While conducting the machining experiments, surface roughness, metal removal rate, and wire wear ratio are considered the responses to evaluate the WEDM performance. Response surface methodology is used to develop the empirical models for these WEDM responses. SiC particulate size and volume percentages are considered the process variables along with pulse-on time, pulse-off time, and wire tension. Analysis of variance (ANOVA) is used to check the adequacy of the developed models. Since the machining responses are conflicting in nature, the problem is formulated as a multi-objective optimization problem and is solved using the Non-dominated Sorting Genetic Algorithm-II to obtain the set of Pareto-optimal solutions. The derived optimal process responses are confirmed by the experimental validation tests, and the results are analyzed by SEM.     

Comparative study of conventional and micro WEDM based on machining of meso/micro Sized Spur Gear

This paper discusses the comparison of micro machining process using conventional and micro wire electrical discharge machining (WEDM) for fabrication of miniaturized components. Seventeen toothed miniaturized spur gear of 3.5 and 1.2 mm outside diameter were fabricated by conventional and micro WEDM respectively. The process parameters for both conventional and micro WEDM were optimized by preliminary experiments and analysis. The gears were investigated for the quality of surface finish and dimensional accuracy which were used as the criteria for the process evaluation. An average surface roughness (R_a) of 50 nm and dimensional accuracy of 0.1–1 μm were achieved in micro WEDM. Whenever applied conventional WEDM for meso/micro fabrication, a R_a surface roughness of 1.8 μm and dimensional accuracy of 2–3 μm were achieved. However, this level of surface roughness and dimensional accuracy are acceptable in many applications of micro engineering. A window of conventional WEDM consisting of low energy discharge parameters is identified for micromachining.     

On surface integrity of miniature spur gears manufactured by wire electrical discharge machining

This paper reports about investigations on some important aspects of surface integrity of the miniature spur gears manufactured by wire electrical discharge machining (WEDM) process. The investigations included study of variation of form errors (deviations in profile and lead) and surface roughness with discharge energy parameters, i.e., voltage and/or pulse-on time for the miniature gears. The effect of WEDM process on flank surface topography, bearing length parameters, microstructure, and microhardness for the best quality miniature gear were also studied. The manufactured miniature gears were of external spur type having 9.8 mm as outside diameter, 4.9-mm thickness, 0.7 mm as module, 12 teeth, and were made of brass. It was found that combination of low discharge energy parameters resulted in better form accuracy, surface finish, and microstructure ensuring enhanced service life and better functional characteristics of the WEDMed miniature gears. The best quality miniature gear had form errors (i.e., lead and profile deviations) as low as 5.4 μm, very little variation in the actual surface topography from the theoretical one, an average surface roughness of 1 μm, and maximum surface roughness within the entire evaluation length as 6.4 μm, showed consistent surface finish measured by other surface roughness parameters, good bearing area curve, and crack-free gear tooth surface without significant alteration in microhardness. Results of the present work demonstrate the superiority of the WEDM process over the conventional miniature gear manufacturing processes.     

Improvement of wire electrical discharge machining efficiency in machining polycrystalline silicon with auxiliary-pulse voltage supply

This study proposes a novel pulse voltage configuration, auxiliary-pulse voltage, for wire electrical discharge machining (WEDM) of polycrystalline silicon (polysilicon) used in solar cell production. It is developed with the objectives of reducing material waste due to the large kerf loss as well as achieving greater efficiency and better quality compared with conventional machining approaches. Experimental results show that compared with conventional-pulse voltage supply, the auxiliary-pulse voltage mode can avoid delay in electrical discharge during pulse-on time. Enhanced frequency of effective discharge for machining would increase machining speed, which would in turn reduce machining groove width, and obtain better surface roughness. In addition, parameters of significant influence on machining characteristics were examined with the Taguchi method, and the optimal combination levels of machining parameters were determined. In sum, our findings reveal that WEDM with auxiliary-pulse voltage supply is an effective approach to machining polysilicon with good quality and high efficiency achieved.     

Improving the surface quality in wire electrical discharge machined specimens by removing the recast layer using magnetic abrasive finishing method

This study explores the feasibility of removing the recast layer formed on aluminum alloy cylindrical specimens machined by wire electrical discharge machining (WEDM) by using magnetic abrasive finishing (MAF). The WEDM is a thermal machining process capable of accurately machining parts with high hardness or complex shapes. The sparks produced during the WEDM process melt the metal’s surface. The molten material undergoes ultra-rapid quenching and forms a layer on the surface defined as recast layer. The recast layer may be full of craters and microcracks which reduce service life of materials tremendously, especially under fatigue loads in corrosive environments. This investigation demonstrates that MAF process, can improve the quality of WEDM machined surfaces effectively by removing the recast layer. The present work studies the effect of some parameters, i.e., linear speed, working gap, abrasive particle size, and finishing time on surface roughness and recast layer thickness using full factorial analysis. Three-level full factorial technique is used as design of experiments for studying the selected factors. In order to indicate the significant factors, the analysis of variance has been used. In addition, an equation based on regression analysis is presented to indicate the relationship between surface roughness and recast layer thickness of cylindrical specimens and finishing parameters. Experimental results show the influence of MAF process on recast layer removal and surface roughness improvement.     

影响线切割加工表面质量的因素分析及对策

就线切割加工中加工表面常出现的烧伤、纹路粗糙、裂纹、变形等质量问题作了详细分析并提出了相应措施,对进一步完善和提高线切割加工质量具有一定意义.     

Strength modeling and optimizing ultrasonic welded parts of ABS-PMMA using artificial intelligence methods

This study analyzes variations in metal removal rate (MRR) and quality performance of roughness average (R _a) and corner deviation (CD) depending on parameters of wire electrical discharge machining (WEDM) process in relation to the cutting of pure tungsten profiles. A hybrid method including response surface methodology (RSM) and back-propagation neural network (BPNN) integrated simulated annealing algorithm (SAA) were proposed to determine an optimal parameter setting. The results of 18 experimental runs via a Taguchi orthogonal table were utilized to train the BPNN to predict the MRR, R _a, and CD properties. Simultaneously, RSM and SAA approaches were individually applied to search for an optimal setting. In addition, analysis of variance was implemented to identify significant factors for the processing parameters. Furthermore, the field-emission scanning electron microscope images show that a lot of built-edge layers were presented on the finishing surface after the WEDM process. Finally, the optimized result of BPNN with integrated SAA was compared with that obtained by an RSM approach. Comparisons of the results of the algorithms and confirmation experiments show that both RSM and BPNN/SAA methods are effective tools for the optimization of parameters in WEDM process.