混粉电火花镜面加工技术及应用

利用自行研制的混粉电火花镜面加工装置，对混粉电火花镜面加工影响因素，加工表面性能等进行了深入研究，找出了粉末特性，工件材料，粉末浓度及放电参数等对混粉电火花镜面加工的影响规律，给出了合理的混粉电火花镜面加工工艺条件，以文中确定的加工工艺条件对铸造和压铸模具进行混粉电火花镜面加工，结果表明，该技术能提高模具制造质量，降低工人劳动强度，缩短模具制造周期。     

关于介质混气电火花加工机理的分析

混气电火花加工是在煤油工作液中混入空气的一种新型的电火花加工方法,本文分析了混气电火花的加工机理及混入气泡的作用。并用实验方法证明了对机理的分析。     

混粉电火花加工技术在粗加工中的应用研究

在对混粉电火花加工机理进行系统研究的基础上，对混粉电火花粗加工中的加工效率和加工表面粗糙度进行了实验研究。结果表明，通过合理选择放电参数，混粉电火花加工在相近加工表面粗糙度时，能显著提高加工效率，从而为混粉电火花加工技术在粗加工中应用提供依据。     

电参数对混粉镜面电火花加工表面粗糙度影响的研究

介绍了混粉镜面电火花加工的实验装置,并应用单因素法初步研究了脉冲电参数对混粉大面积镜面电火花加工工件表面粗糙度的影响规律。     

混粉镜面电火花加工在模具制造中的应用研究

论述了混粉镜面电火花加工原理，介绍了混粉镜面加工的实验装置及不同加工方法的优劣，分析了混粉镜面电火花加工方法在型腔模具制造中的应用及发展。     

混粉电火花加工表面显微裂纹的研究

对混粉电火花加工表面的显微裂纹进行了研究.选用铝粉工作液和硅粉工作液,在不同的参数条件下对两种工件材料进行了加工实验,得到了相应的裂纹分布图.结果表明,脉冲宽度对加工后表面显微裂纹的影响十分明显,峰值电流、粉末种类、工件材料等因素对显微裂纹的影响则并不明显.     

粉末特性对混粉电火花镜面加工的影响

用实验方法研究了粉末粒度、形状及导电性对混粉电火花镜面加工表面粗糙度的影响,同时对混粉电火花加工表面的耐磨性和耐蚀性进行了研究。结果表明,粉末粒度和导电性对混粉电火花加工表面粗糙度有较大的影响;混粉电火花镜面加工不但能改善加工表面粗糙度,且能提高加工表面的耐磨性和耐蚀性。     

精微电火花加工多模式实验装置的设计

针对精微电火花加工原理的实验研究,设计了一套用于精微电火花加工实验的多模式装置。该装置主要基于STM32系列微控制器,设计了RC脉冲、等频率脉冲、等电流宽度脉冲3种脉冲电源模式和峰值电压检测、峰值电流检测、击穿延时检测3种间隙状态检测模式。整体电路结构较简单,扩展性好,且能灵活切换各种模式,其最小脉冲宽度设计值为100ns。     

新型混粉电火花镜面加工实验装置的研制

针对混粉电火花加工的实验装置成本高、电蚀产物分离难等问题,利用水力旋流器超细分级分离的特性,设计了可在线过滤混粉电火花加工工作液的新型实验装置,同时设计了新型的储液箱搅拌系统和工作液体槽内的搅拌装置,能很好地保证混粉电火花加工过程中粉末浓度的均匀性.该实验装置的研制为将来实现混粉、常规电火花加工工作液箱一体化的电火花成形机提供了可行性验证.     

超声振动辅助混粉电解电火花加工工艺研究

提出了一种使用超声振动辅助混粉电解电火花铣削加工硬脆性非导电材料的方法。通过对高硼玻璃进行超声振动作用下的混粉电解电火花铣削加工实验,研究了超声振动对电解电火花铣削加工表面质量的影响规律。结果表明:采用超声振动辅助混粉电解电火花加工,可获得较好的表面质量。     

超声振动辅助气中放电加工的研究

介绍了超声振动辅助气中放电加工技术，试验研究了电压、脉冲宽度、峰值电流、超声振幅及气体介质压力等参数对加工效率、工件表面粗糙度及电极损耗的影响，并对试验结果进行了分析。     

Electrical discharge machining of Ti6Al4V with a bundled electrode

The aim of this study is to investigate an efficient Ti6Al4V electrical discharge machining (EDM) process with a bundled die-sinking electrode. The feasibility of machining Ti6Al4V with a bundled electrode was studied and its effect on EDM performance was compared experimentally using a solid die-sinking electrode. The simulation results explain the high performance of the EDM process with a bundled electrode by through the use of multi-hole inner flushing to efficiently remove molten material from the inter-electrode gap and through the improved ability to apply a higher peak current. A 3-factor, 3-level experimental design was used to study the relationships between 2 machining performance parameters (material removal rate: MRR, tool wear ratio: TWR) and 3 machining parameters (fluid flow rate, peak current and pulse duration). The main effects and influences of the 2-factor interactions of these parameters on the performances of the EDM process with the bundled electrode are discussed.     

Influences of pulsed power condition on the machining properties in micro EDM

Micro EDM is one of the most powerful technologies which are capable of fabricating micro-structure. However, there are many operating parameters that affect the micro EDM process. Since the EDM is basically a thermal process, the supplying electrical condition can be an important factor. The conditions generally consist of several parameters such as electrical current, voltage, pulse duration, spark gap, and others. Those are decisive in removal rate, wear rate, and machining accuracy, which are characteristics of EDM. In this study, the influences of EDM pulse condition on the micro EDM properties were investigated. Voltage, current, and on/off time of the pulse were selected as experimental parameters based on a simple equation for the material removal rate. The pulse condition is particularly focused on the pulse duration and the ratio of off-time to on-time, and the machining properties are reported on tool wear, material removal rate, and machining accuracy. The experimental results show that the voltage and current of the pulse exert strongly to the machining properties and the shorter EDM pulse is more efficient to make a precision part with a higher material removal rate.     

Machining characteristics of magnetic force-assisted EDM

The gap conditions of electrical discharge machining (EDM) would significantly affect the stability of machining progress. Thus, the machining performance would be improved by expelling debris from the machining gap fast and easily. In this investigation, magnetic force was added to a conventional EDM machine to form a novel process of magnetic force-assisted EDM. The beneficial effects of this process were evaluated. The main machining parameters such as peak current and pulse duration were chosen to determine the effects on the machining characteristics in terms of material removal rate (MRR), electrode wear rate (EWR), and surface roughness. The surface integrity was also explored by a scanning electron microscope (SEM) to evaluate the effects of the magnetic force-assisted EDM. As the experimental results suggested that the magnetic force-assisted EDM facilitated the process stability. Moreover, a pertinent EDM process with high efficiency and high quality of machined surface could be accomplished to satisfy modern industrial applications.     

PZT激励同步压缩放电通道微细电火花加工工艺参数对加工结果的影响

提出了压电陶瓷(piezoelectric ceramic transducer,PZT)激励同步压缩放电通道微细电火花加工,目的在于改善微细电火花加工的放电环境。介绍了PZT激励同步压缩放电通道微细电火花加工原理,研究了开路电压、脉冲宽度、脉冲频率和峰值电流对其电极损耗和材料去除率的影响,并与不采用压缩通道方法的微细电火花加工进行了对比。结果表明:同等条件下,采用PZT激励同步压缩放电通道技术,提高了加工过程的稳定性和材料去除率,降低了电极损耗率,有效改善了放电环境。     

超声振动辅助混粉电火花放电表面强化实验研究

采用超声振动辅助混粉电火花放电表面强化技术进行了65Mn钢表面强化实验。研究了粉末浓度、脉冲宽度、脉冲间隔、峰值电流、超声振幅对工件表面强化层形貌和表面粗糙度的影响。研究表明,在低能量、低振幅和一定粉末浓度条件下,可使粉末渗入工件表面形成强化层。峰值电流过大会导致TiC粉末全部熔融,在超声振动作用下抛离工件表面,不能形成强化层。辅助超声振动可显著提高工件表面的耐磨性。     

SiC/Al功能梯度材料的电火花多脉冲温度场仿真

为探索Si C/Al功能梯度材料的电火花加工特性,建立了电火花加工连续多脉冲放电温度场仿真模型,开展了连续多脉冲放电蚀除动态模拟仿真研究,应用生死单元法分析了放电凹坑位置的随机分布情况,研究了峰值电流、脉冲宽度对放电凹坑和材料去除率的影响规律,并进行了实验验证。结果表明:随着峰值电流和脉冲宽度的增大,材料去除率逐渐提高,仿真结果与实验结果具有相同的变化趋势;误差分析显示,理论值与实验结果最大误差为9.84%,最小误差为5.10%。     

精细电规准对NAK80材料准镜面电火花加工表面三维幅值参数的影响

通过正交试验,研究了峰值电流、脉冲间隔、开路电压、脉冲宽度等精细电规准在不同水平下,对NAK80材料准镜面电火花加工的三维表面参数(Sa、Sq和Sz)的影响。试验结果显示,在上述因素中,峰值电流和脉冲间隔对评价指标影响较大,脉冲宽度影响最小。通过方差分析,试验选定因素对评价指标的影响均非显著,并通过信噪比获得最优的加工参数。     

电火花加工脉冲电源人机接口界面设计

利用 12 8× 2 4 0规格点阵式LCD模块设计了电火花加工脉冲电源人机接口界面 ,在汉字提示下能够完成加工尺寸、加工工艺参数设定、加工过程跟踪及设备状态监控等功能 ,使界面变得更为友好 ,大大地提高了脉冲电源的性能。