高速走丝二次电火花线切割工艺的探索

对高速走丝线切割机床与低速走丝线切割机床的加工工艺方法进行分析。在高速走丝机床上，采用二次切割加工工艺，提高其加工工件的技术指标，使之接近或达到低速走丝机床的技术参数。     

高速走丝电火花线切割机床多次切割的实现

分析了高速走丝电火花线切割机床多次切割的条件及进行稳定多次切割需采取的措施,通过对机床机械结构及控制系统功能的改进与完善,采用洗涤性能良好的复合工作液,成功研制出具有稳定多次切割功能的商品化机床。第一次切割最高效率已超过200mm2/min,第四次切割后在平均切割效率大于50mm2/min的条件下,表面粗糙度Ra<0.8μm。     

一种全闭环中走丝电火花线切割机床数控系统

研究了中走丝电火花线切割机床脉冲放电特性,提出了一种高速数字化采样和间隙跟踪方法,同时建立了智能型放电工艺数据库,提高了切割过程放电效率。为改进切割精度和表面粗糙度,工作台运动采用了一种闭环位置控制方案,基于双平面同步插补法实现了4轴协调运动控制,并采用C补偿原理解决了多次切割控制问题。基于嵌入式操作系统,设计并实现了可视化编程与控制集成软件。实际切割实验数据显示,采用这种数控系统后,中走丝线切割机床的可靠性和加工精度有了显著提高。     

基于DK7740P电火花线切割机床多次切割研究

在国内电加工界对电火花丝线切割的研究基础上,结合DK7740P线切割机床的应用,阐述高速走丝多次切割的基本条件,以及多次切割过程中各种工艺参数的确定。详细分析了在线切割机床上进行单次和多次切割加工时尺寸精度的对比实验,表明在高速走丝线切割机床上采用多次切割技术,可以明显提高加工精度,带来显著的经济效益。     

高速往复走丝电火花线切割的现状及发展

分析了我国独有的高速往复走丝电火花线切割机床的市场分布、容量、在国内外的应用状况及技术发展水平和目前存在的主要问题。根据高速往复走丝电火花线切割的技术特点指出其发展的主要方向应定位在:针对零件的高效稳定加工;大厚度及大锥度加工;中等精度的多次切割加工;提高加工参数的可控性及机床的自动化水平;提高机床的节能环保性等领域。     

高低双速走丝电火花线切割工艺试验研究

阐述了高低双速走丝电火花线切割机的设计概念、实现方式和特点。通过一次高速走丝大能量切割、多次单向低速走丝切割并加大电极丝张力等措施,与高速走丝多次切割(中走丝)方式进行了对比试验。结果表明高低双速走丝的切割精度、腰鼓形均比中走丝切割方式有明显改善,而表面粗糙度值则略有提高。     

电火花线切割加工中的断丝现象与解决办法

数控高速走丝电火花线切割加工,首先必须保证在切割过程中不断丝。如果在切割工件过程中发生断丝,不仅会带来重新上丝的麻烦,造成一定的经济损失,而且会在工件上产生断丝痕迹,影响加工质量,严重时会造成工件报废。本文介绍了在线切割加工中的断丝问题,论述了产生断丝的原因,从线切割机床和工艺特点出发,对防止产生断丝的措施进行了探讨。     

线切割加工参数对工艺指标的影响分析及合理选择

电参数和非电参数是影响线切割加工工艺指标的两个重要方面，通过对DK7732型精密数控中走丝线切割机床的应用和研究，经过多次加工试验，得到了工艺试验数据，结合试验数据分析了工艺指标的影响因素，为实验教学和产品加工提供了科学依据。     

电火花线切割技术的研究现状及发展趋势

对电火花线切割加工技术的现状进行了分析。并对新型走丝系统、高度自动化及人工智能技术、高速走丝的多次切割技术、微细电火花线切割加工技术等方面的最新进展进行了概述。     

基于复合工作液的多次切割放电机理及修正量规律研究

研究了在复合工作液条件下高速走丝电火花线切割多次切割的放电机理及理论修正量与实际修正量的关系。结果表明,采用复合工作液的多次切割的极间放电仍然是传统的间隙放电,在综合考虑第一次切割放电间隙与最后一次放电间隙差异的情况下,多次切割的实际修正量与理论修正量是一致的。     

探讨高速走丝电火花线切割加工断丝故障分析及预防

高速走丝电火花线切割加工能够满足我国模具制造以及机械加工的需要,但是在高速走丝电火花线切割加工的过程中容易出现断丝的情况,这对于快速的机械加工以及模具制造而言有着非常大的影响。详述高速走丝电火花线切割加工的原理、高速走丝电火花线切割加工断丝的故障原因以及高速走丝电火花切割加工中断丝故障的解决方法及预防。对于高速走丝电火花线切割加工中断丝的情况要进行分析并预防。     

数控快走丝电火花线切割加工工艺方法研究

通过对数控快走丝电火花线切割加工中如何加工穿丝孔、装夹工件、编制程序、选择电参数、使用工作液、应用多次切割工艺方法以及诊断加工故障等工艺方法进行研究。形成了一套完整的工艺方法，效果良好。     

复杂曲面零件电火花线切割加工系统研究

开发了以新型翻转式自动分度数控回转工作台为核心的复杂曲面电火花线切割加工系统。阐明了系统的运动规律,建立了通用数学模型,并进行了计算机仿真和样件加工实验研究。利用该数控回转工作台,采用二维加工信息流控制技术,与国产高速走丝电火花线切割机床相结合,从根本上解决复杂曲面零件高速走丝电火花线切割加工的关键技术问题,大幅度提高了线切割加工的加工质量和生产效率。该方法在模具制造中得到了良好的应用。     

Modeling and multiresponse optimization on WEDM for HSLA by RSM

Wire electric discharge machining (WEDM) is a nonconventional machining method to cut hard and conductive material with the help of a moving electrode. High-strength low-alloy steel (HSLA) is a hard alloy with high hardness and wear-resisting property. The purpose of this study is to investigate the effect of parameters on cutting speed and dimensional deviation for WEDM using HSLA as workpiece. It is seen that the most prominent factor for cutting speed and dimensional deviation is pulse-on time, while two-factor interactions play an important role in this analysis. Response surface methodology was used to optimize the process parameter for cutting speed and dimensional deviation. The central composite rotatable design was used to conduct the experiments. The analysis of variance was used for the investigation of significant factors.     

Determining cutting parameters in wire EDM based on workpiece surface temperature distribution

The material removal process in wire electrical discharge machining (WEDM) may result in work-piece surface damage due to the material thermal properties and the cutting parameters such as varying on-time pulses, open circuit voltage, machine cutting speed, and dielectric fluid pressure. A finite element method (FEM) program was developed to model temperature distribution in the workpiece under the conditions of different cutting parameters. The thermal parameters of low carbon steel (AISI4340) were selected to conduct this simulation. The thickness of the temperature affected layers for different cutting parameters was computed based on a critical temperature value. Through minimizing the thickness of the temperature affected layers and satisfying a certain cutting speed, a set of the cutting process parameters were determined for workpiece manufacture. On the other hand, the experimental investigation of the effects of cutting parameters on the thickness of the AISI4340 workpiece surface layers in WEDM was used to validate the simulation results. This study is helpful for developing advanced control strategies to enhance the complex contouring capabilities and machining rate while avoiding harmful surface damage.     

The effect of the cutting parameters on performance of WEDM

In this study, variations of cutting performance with pulse time, open circuit voltage, wire speed and dielectric fluid pressure were experimentally investigated in Wire Electrical Discharge Machining (WEDM) process. Brass wire with 0.25 mm diameter and AISI 4140 steel with 10 mm thickness were used as tool and work materials in the experiments. The cutting performance outputs considered in this study were surface roughness and cutting speed. It is found experimentally that increasing pulse time, open circuit voltage, wire speed and dielectric fluid pressure increase the surface roughness and cutting speed. The variation of cutting speed and surface roughness with cutting parameters is modeled by using a regression analysis method. Then, for WEDM with multi-cutting performance outputs, an optimization work is performed using this mathematical models. In addition, the importance of the cutting parameters on the cutting performance outputs is determined by using the variance analysis (ANOVA).     

Analyzing the surface layer after WEDM depending on the parameters of a machine for the 16MnCr5 steel

The efficient wire electric discharge machining (WEDM) technology is a trade-off between the cutting speed and the resulting surface quality. A typical morphology of a surface machined using WEDM contains a large number of craters caused by the electric sparks generated in the cutting process. The paper analyzes the influence of the cutting speed on the quantitative and qualitative evaluation of the craters formed on the surface of a workpiece made of the 16MnCr5 steel. Applying metallography to cross-section microscopic slides, diffusion subsurface damages were studied caused by the cutting. The diffusion processes taking place between the electrode and the material machined were studied using a local point EDX microanalysis applied both to the machined surfaces and to the cross sections. A detailed study was also carried out of the brass electrode to measure its wear rate caused by the cutting process as well as its degradation in terms of the quality of its morphology and the chemical composition of surface.     

快走丝电火花线切割加工仿真系统

通过神经网络技术建立了快走丝电火花线切割加工工艺模型 ,利用穷举法建立了具有一定人工智能的工艺参数全局优化系统 ,开发了模具电火花加工过程仿真系统。该系统不仅可以精确预测加工效果 ,而且克服了工艺参数表的局限性 ,弥补了建立在工艺参数表基础上的参数自动选取系统的缺陷 ,实现了工艺参数全局最优化。测试结果及实际使用结果表明本文所建立的仿真系统反映了机床的加工工艺特性 ,预测误差基本控制在 8%内 ,系统的参数优化选取功能使机床的加工性能得以充分发挥。仿真系统具有广泛的通用性 ,可适用于不同类型的线切割加工机床。     

Optimization of wire electrical discharge machining (WEDM) process parameters using Taguchi method

Wire electrical discharge machining (WEDM) is extensively used in machining of conductive materials when precision is of prime importance. Rough cutting operation in WEDM is treated as a challenging one because improvement of more than one machining performance measures viz. metal removal rate (MRR), surface finish (SF) and cutting width (kerf) are sought to obtain a precision work. Using Taguchi’s parameter design, significant machining parameters affecting the performance measures are identified as discharge current, pulse duration, pulse frequency, wire speed, wire tension, and dielectric flow. It has been observed that a combination of factors for optimization of each performance measure is different. In this study, the relationship between control factors and responses like MRR, SF and kerf are established by means of nonlinear regression analysis, resulting in a valid mathematical model. Finally, genetic algorithm, a popular evolutionary approach, is employed to optimize the wire electrical discharge machining process with multiple objectives. The study demonstrates that the WEDM process parameters can be adjusted to achieve better metal removal rate, surface finish and cutting width simultaneously.