共查询到17条相似文献,搜索用时 161 毫秒
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为了研究超声振动和混粉对电火花加工的影响,基于传热理论,结合超声和混粉特性建立了超声混粉电火花传热模型。基于建立的传热模型对超声混粉电火花加工去除材料过程进行瞬态热力学仿真,并通过实验验证了仿真结果的准确性。通过仿真和实验分析了普通电火花、超声电火花、混粉电火花和超声混粉电火花四种加工方式,结果表明超声混粉电火花加工效率比普通电火花加工效率提高了23%。加入混粉和施加超声可以减少加工表面积碳,提高表面质量;可以使放电凹坑变得更加规则,使表面粗糙度降低。混粉电火花加工相对于普通电火花加工其表面粗糙度平均降低了8.9%,超声混粉电火花表面粗糙度相对于普通电火花平均降低了4.3%。 相似文献
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以石墨为工具电极,在精密电火花成型机床上进行混粉电火花加工,对Ti-6Al-4V钛合金表面进行强化处理。利用TR200手持式粗糙度仪对传统电火花加工和混粉电火花加工的表面进行粗糙度的测量,并利用SEM、XRD等研究混粉电火花加工参数对加工表面层的影响。在MMU-10G型摩擦磨损试验机上对基体表面、普通电火花加工工件及磁力搅拌混粉电火花加工工件表面进行摩擦磨损试验。磁力搅拌混粉电火花加工使得工件表面的粗糙度降低且随着峰值电流和脉冲宽度的增大而增大,提高了工件表面质量。随着峰值电流和脉冲宽度的增大强化层越均匀、致密性越好且强化层越厚。工件表面还生成了TiC硬质合金相使工件表面耐磨性得到提高,工件表面性能显著改善。混粉电火花加工后工件表面得到强化。 相似文献
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混粉电火花加工表面粗糙度的经验公式 总被引:2,自引:0,他引:2
分析了混粉电火花加工的原理,建立了混粉电火花加工回归方程数学模型,在综合考虑各种因素的基础上,推出混粉电火花加工表面粗糙度经验公式,这对混粉电火花加工的实验研究和理论研究有指导意义。 相似文献
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提出一种混粉准干式电火花加工技术,其加工介质是气液固三相流混合物。试验结果表明,材料去除率与表面粗糙度随脉冲宽度、峰值电流及分层厚度的增大而增大,脉冲间隙作用则相反,提高空气压力既有助于提高材料去除率又可降低表面粗糙度,电极损耗随脉冲宽度增大而减小,当脉冲宽度较大时电极损耗接近于零,随峰值电流增大而增加。由于液滴、粉末的介入,气体介质的绝缘强度降低,放电间隙会增加,有利于电蚀产物的排除,可减少短路、电弧放电的发生率,加工稳定性得到提高,从而材料去除率得到提高;由于粉末会产生放电分散效果,电蚀凹坑深度减小,工件表面粗糙度降低。 相似文献
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Nor Ain Jamil Hosni 《Machining Science and Technology》2020,24(3):398-424
AbstractPowder mixed EDM (PMEDM) is recognized as an advanced and innovative technique with enhanced performance and limited drawbacks in comparison to conventional EDM method. This study investigates the effect of powder particle size, various powder concentrations (Cp), and surfactant concentrations (Cs) on the performance of EDM. Since the machining characteristics are highly dependent on the dielectric performances, significant attention has been directed to introduce Cr powder and Span-20 surfactant into the dielectric fluid to achieve higher productivity and enhanced surface integrity. The EDM machining was carried out on AISI D2 hardened steel through ´Plug & Plaý dielectric circulating system attached to the main machine in order to evaluate the machining performances (i.e. MRR, EWR, and Ra). Interestingly, machining performance was improved with combination of Cr powder mixed and span-20 surfactant. By comparing the performance of span-20 surfactant and micro-nano chromium, the result within selected parameters shows that the span-20 surfactant and nano-chromium is the better choice for the EDM of AISI D2 hardened steel. In the machinability studies, the EDM machining of AISI D2 hardened steel by using span-20 surfactant and nano-chromium has exhibited the excellent machining performances, which led to 45.08% MRR enhancement and 68.89% Ra enhancement comparing to micro-chromium powder and span-20 surfactant led to 35.28% MRR and 28.96% Ra. Furthermore, cost analysis revealed that the nano-Cr powder size was approximately 4 times more economical than micro-Cr powder in machining of AISI D2 hardened steel, although the price for 1?kg is quite expensive. 相似文献
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Paulo Peças Elsa Henriques 《The International Journal of Advanced Manufacturing Technology》2008,37(11-12):1120-1132
The addition of powder particles to the electrical discharge machining (EDM) dielectric fluid modifies some process variables and creates the conditions to achieve a higher surface quality in large machined areas. This paper presents a new research work that aims to study the improvement in the polishing performance of conventional EDM when used with a powder-mixed-dielectric (PMD-EDM). The analysis was carried out varying the silicon powder concentration and the flushing flow rate over a set of different processing areas and the effects in the final surface were evaluated. The evaluation was done by surface morphologic analysis and measured through some quality surface indicators. The results show the positive influence of the silicon powder in the reduction of crater dimensions, white-layer thickness and surface roughness. Moreover, it was demonstrated that an accurate control of the powder concentration and flushing flow is a requirement for achieving an improvement in the process polishing capability. 相似文献
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Surface Improvement Using a Combination of Electrical Discharge Machining with Ball Burnish Machining Based on the Taguchi Method 总被引:4,自引:4,他引:0
Y.C. Lin B.H. Yan F.Y. Huang 《The International Journal of Advanced Manufacturing Technology》2001,18(9):673-682
This study investigates the feasibility of improving surface integrity via a novel combined process of electrical discharge
machining (EDM) with ball burnish machining (BBM) using the Taguchi method. To provide burnishing immediately after the EDM
process, ZrO2 balls were attached to the tool electrode in the experiments. To verify the optimal process, three observed values, i.e.
material removal rate, surface roughness, and improvement ratio of surface roughness were chosen. In addition, six independent
parameters were adopted for evalu-ation by the Taguchi method. From the ANOVA and S/N ratio response graph, the significant
parameters and the optimal combination level of machining parameters were obtained. Experimental results indicate that the
combined process effectively improves the surface roughness and eliminates the micro pores and cracks caused by EDM. Therefore,
the combination of EDM and BBM is a feasible process by which to obtain a fine-finishing surface and achieve surface modification. 相似文献
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