Abstract Powder 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.

中文翻译：

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表面活性剂（Span-20）在AISI D2硬化钢粉末混合放电加工（PMEDM）中的实验研究和经济性分析

摘要 粉末混合电火花加工 (PMEDM) 被认为是一种先进的创新技术，与传统的电火花加工方法相比，它具有增强的性能和有限的缺点。本研究调查了粉末粒度、各种粉末浓度 (Cp) 和表面活性剂浓度 (Cs) 对 EDM 性能的影响。由于加工特性高度依赖于介电性能，因此人们非常注意将 Cr 粉和 Span-20 表面活性剂引入介电流体中，以实现更高的生产率和增强的表面完整性。为了评估加工性能（即 MRR、EWR 和 Ra），通过连接到主机的“Plug & Plaý 介质循环系统”在 AISI D2 硬化钢上进行 EDM 加工。有趣的是，Cr粉混合和span-20表面活性剂的组合提高了加工性能。通过比较span-20表面活性剂和微纳米铬的性能，在选定参数范围内的结果表明，span-20表面活性剂和纳米铬是AISI D2硬化钢电火花加工的更好选择。在可加工性研究中，使用span-20表面活性剂和纳米铬对AISI D2硬化钢进行电火花加工，表现出优异的加工性能，与微铬粉和span相比，MRR提高45.08%，Ra提高68.89%。 -20 表面活性剂导致 35.28% MRR 和 28.96% Ra。此外，成本分析表明，在加工 AISI D2 淬火钢时，纳米 Cr 粉末尺寸比微米 Cr 粉末经济约 4 倍，