Nimonic C263, a nickel-based superalloy, finds extensive application in manufacturing of complex parts in gas turbine, aircraft and automotive industries exclusively for exhaust sections. Machining of the alloy through traditional approach is a difficult task owing to its poor thermal conductivity, work hardening and high strength properties. However, the superalloy can be machined up to desired accuracy by non-traditional machining processes like electrical discharge machining (EDM). Yet again, machining of these difficult-to-machine materials not only consumes a significant amount of energy, but also produces unpleasant noise, hindering the sustainable aspect of the process. To meet the requisite of sustainable EDM and explore the machinability, an experimental investigation is proposed in this work, when Nimonic C263 superalloy is machined with three different electrodes, viz. copper, tungsten, and copper–tungsten. Outcomes of important process parameters, viz. voltage (U), discharge current (I), pulse-on-time (T_on), duty factor (τ), and electrode material, are studied on the responses, viz. specific energy consumption, machining noise (N), material removal rate, electrode wear rate, surface roughness (R_a) and radial overcut (C). Analysis of variance is conducted to analyse the influence of each parameter on the responses. A scanning electron microscope investigation is carried out to analyse the pre-machining and post-machining scenarios on the machined surface. The multiple responses are converted into single response by calculating the net outranking flow by application of preference ranking organization method for enrichment evaluation (PROMETHEE) approach. The PROMITHEE-based results are further improved by using a hybrid cuckoo search algorithm (combined PROMITHEE-based cuckoo search). A confirmative test is further conducted on the optimum machining conditions obtained by the hybrid approach (combination of PROMITHEE and cuckoo search) indicating an overall improvement of 6.02% for the responses, validating the proposed work.

Nimonic C263是一种镍基高温合金，在燃气轮机，飞机和汽车行业中专门用于排气段的复杂零件的制造中得到广泛应用。由于其导热性差，加工硬化和高强度特性，通过传统方法加工合金是一项艰巨的任务。但是，可以通过诸如放电加工（EDM）的非传统加工工艺将超级合金加工至所需的精度。再一次，对这些难于加工的材料进行机械加工不仅消耗大量能量，而且还会产生令人不快的噪音，从而阻碍了该工艺的可持续发展。为了满足可持续电火花加工的需求并探索其可加工性，这项工作提出了一项实验研究，当用三个不同的电极加工Nimonic C263超级合金时。铜，钨和铜钨。重要过程参数的结果，即。电压 （U），放电电流（I），脉冲导通时间（T _on），占空比（τ）和电极材料均根据响应进行研究，即。比能耗，加工噪声（N），材料去除率，电极磨损率，表面粗糙度（R _a）和径向切削（C）。进行方差分析以分析每个参数对响应的影响。进行了扫描电子显微镜研究，以分析加工表面上的加工前和加工后场景。通过使用优先级排序组织方法进行富集评估（PROMETHEE）方法来计算净胜出流，从而将多个响应转换为单个响应。通过使用混合杜鹃搜索算法（基于PROMITHEE的杜鹃搜索组合），可以进一步改善基于PROMITHEE的结果。对通过混合方法（PROMITHEE和布谷鸟搜索的组合）获得的最佳加工条件进一步进行了验证性测试，表明响应的整体改进为6.02％，从而验证了所提出的工作。