Ishfaq Kashif, Sana Muhammad, Waseem Muhammad Umair, Ashraf Waqar Muhammad, Anwar Saqib, Krzywanski Jaroslaw
Department of Industrial and Manufacturing Engineering, University of Engineering and Technology, Lahore 54890, Pakistan.
Sargent Centre for Process Systems Engineering, Department of Chemical Engineering, University College London, Torrington Place, London WC1E 7JE, UK.
Micromachines (Basel). 2023 Jul 31;14(8):1536. doi: 10.3390/mi14081536.
The critical applications of difficult-to-machine Inconel 617 (IN617) compel the process to be accurate enough that the requirement of tight tolerances can be met. Electric discharge machining (EDM) is commonly engaged in its machining. However, the intrinsic issue of over/undercut in EDM complicates the achievement of accurately machined profiles. Therefore, the proficiency of deep cryogenically treated (DCT) copper (Cu) and brass electrodes under modified dielectrics has been thoroughly investigated to address the issue. A complete factorial design was implemented to machine a 300 μm deep impression on IN617. The machining ability of DCT electrodes averagely gave better dimensional accuracy as compared to non-DCT electrodes by 13.5% in various modified dielectric mediums. The performance of DCT brass is 29.7% better overall compared to the average value of overcut (OC) given by DCT electrodes. Among the non-treated (NT) electrodes, the performance of Cu stands out when employing a Kerosene-Span-20 modified dielectric. In comparison to Kerosene-Tween-80, the value of OC is 33.3% less if Kerosene-Span-20 is used as a dielectric against the aforementioned NT electrode. Finally, OC's nonlinear and complex phenomena are effectively modeled by an artificial neural network (ANN) with good prediction accuracy, thereby eliminating the need for experiments.
难加工的因科镍合金617（IN617）的关键应用要求加工过程足够精确，以满足严格的公差要求。电火花加工（EDM）常用于其加工。然而，电火花加工中存在的过切/欠切固有问题使精确加工轮廓的实现变得复杂。因此，为了解决该问题，对经过深冷处理（DCT）的铜（Cu）和黄铜电极在改性电介质下的性能进行了深入研究。采用完全析因设计在IN617上加工一个300μm深的压痕。在各种改性电介质介质中，与未经过深冷处理的电极相比，深冷处理电极的加工能力平均可使尺寸精度提高13.5%。与深冷处理电极给出的过切（OC）平均值相比，深冷处理黄铜的整体性能要好29.7%。在未处理（NT）电极中，当使用煤油-司盘-20改性电介质时，铜电极的性能较为突出。与煤油-吐温-80相比，对于上述未处理电极，若使用煤油-司盘-20作为电介质，过切值可降低33.3%。最后，通过人工神经网络（ANN）有效地对过切的非线性和复杂现象进行了建模，预测精度良好，从而无需进行实验。
