ABSTRACT

Fabrication of the 316 L steel with moderate surface roughness (SR) and thin recast layer (RLT) is very difficult using both the conventional and non-traditional machining processes. Due to the stochastic behavior of electro-discharge machining (EDM) process, the machining performances significantly rely on the system variables. This research work aims to investigate the influences of EDM method variables on the machining performances during the machining of 316 L steel. Another goal is to minimize the performances by applying nano-hydroxyapatite (HA) particles in the EDM-Oil. Moreover, the optimal solutions for processing of 316 L through the NSGA-II method are proposed in this research. Followed by the pulse-on time and HA amount, ANOVA study reports peak current being the most important parameter for the responses such RLT and SR. The augment of peak current, HA amount, and pulse-on time result comparatively lower RLT and SR than the previous studies. The best 7 solutions selected from the predicted 120 solutions following the objectives are proposed generating the Pareto frontiers. Less than 10% of the validation tests errors confirm the high accuracy of the predicted solutions. The present research proposed a potential and cost-effective method for processing of 316 L steel.

摘要

使用传统和非传统加工工艺制造具有中等表面粗糙度 (SR) 和薄重铸层 (RLT) 的 316 L 钢非常困难。由于放电加工 (EDM) 过程的随机行为，加工性能在很大程度上依赖于系统变量。本研究工作旨在研究电火花加工方法变量对 316 L 钢加工过程中加工性能的影响。另一个目标是通过在 EDM-Oil 中应用纳米羟基磷灰石 (HA) 颗粒来最小化性能。此外，本研究还提出了通过 NSGA-II 方法处理 316 L 的最佳解决方案。其次是脉冲开启时间和 HA 量，方差分析研究报告峰值电流是 RLT 和 SR 等响应的最重要参数。与之前的研究相比，峰值电流、HA 量和脉冲开启时间的增加导致 RLT 和 SR 相对较低。建议从遵循目标的预测的 120 个解决方案中选出的最佳 7 个解决方案生成帕累托边界。不到 10% 的验证测试错误证实了预测解决方案的高精度。本研究提出了一种潜在且经济高效的 316 L 钢加工方法。