Purpose

The main objective of this experimental work is to analyze and measure the form tolerances namely flatness and squareness while machining a meso deep hole in EDM on Inconel-718 material plate.

Design/methodology/approach

The experiments were performed on 15 amps rated SPARKONIX-EDM as per DOE (design of experiments). Kerosene was used as a dielectric along with constant pressure of 0.2 kg/cm² for all trial runs. The currents T_on and T_off were selected as process constraints to conduct experimental trials. The MRR, EWR, machining time and form tolerances were considered as output responses. The experimental outcomes were optimized by hybrid optimization using Taguchi and GRA (grey relational analysis) method.

Findings

The EDM process parameters for Ni-based super alloy namely Inconel-718 had optimized by using GRA method coupled with Taguchi method. The optimum solution has been calculated for MRR, EWR, machining time and form tolerances namely squareness and flatness. The optimized parameters for the output responses in EDM process are Peak current (Ip) 12 Amps, 400 µs T_on (pulse on time) and 10 µs T_off (pulse off time). An attempt had also been made to attain Max. and Min. Evaluation of MRR and form tolerances, respectively. The attained optimum outcomes had also been examined through a real experiment and established to be satisfactory.

Practical implications

This article will facilitate the defense, aerospace and EDM industries to improve their productivity with closer tolerances.

Originality/value

The optimized parameters by multi-parametric optimization showed the considerable improvement in the process and will facilitate the defense, aerospace and EDM industries to improve their productivity with closer tolerances.

中文翻译：

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Inconel-718板材电火花细观深方孔形状公差分析及多参数优化GRA法

目的

本实验工作的主要目的是分析和测量形状公差，即平面度和垂直度，同时在 Inconel-718 材料板上用 EDM 加工细观深孔。

设计/方法/方法

根据 DOE（实验设计），在 15 安培额定 SPARKONIX-EDM 上进行实验。对于所有试验运行，煤油被用作电介质以及0.2 kg/cm ^{2 的}恒定压力。选择电流T _on和T _off作为工艺约束来进行实验试验。MRR、EWR、加工时间和形状公差被视为输出响应。使用田口和GRA（灰色关联分析）方法通过混合优化来优化实验结果。

发现

采用GRA法结合田口法优化了镍基高温合金Inconel-718的电火花加工工艺参数。已针对 MRR、EWR、加工时间和形状公差（即垂直度和平面度）计算出最佳解决方案。EDM 过程中输出响应的优化参数是峰值电流 (Ip) 12 安培、400 µs T _on（脉冲导通时间）和 10 µs T _off（脉冲关断时间）。也曾尝试达到 Max。和敏。分别评估 MRR 和形状公差。获得的最佳结果也通过实际实验进行了检查，结果令人满意。

实际影响

本文将促进国防、航空航天和 EDM 行业以更紧密的公差提高生产力。

原创性/价值

通过多参数优化优化的参数显示了该过程的显着改进，将有助于国防、航空航天和 EDM 行业以更紧密的公差提高生产率。