| URN | etd-0727125-065454 | Statistics | This thesis had been viewed 26 times. Download 0 times. |
| Author | Keng-Hung Lin | ||
| Author's Email Address | No Public. | ||
| Department | Institute Of Mechanical Engineering | ||
| Year | 2024 | Semester | 2 |
| Degree | Master | Type of Document | Master's Thesis |
| Language | zh-TW.Big5 Chinese | Page Count | 57 |
| Title | The Study on the characteristics of end face milling rotating electrode in workpiece processing | ||
| Keyword | |||
| Abstract | During the finishing stage of electrical discharge machining (EDM), the discharge voltage and gap settings are relatively small, which can easily lead to poor debris removal and carbon deposition in the machining area. If the carbon deposits are not promptly eliminated, secondary discharges may occur, which not only reduce machining stability and efficiency but also degrade the surface roughness of the workpiece, making it difficult to achieve the desired quality. Consequently, this increases machining time and overall cost. To address this issue, the present study developed a cylindrical electrode with end-face groove designs. These grooves serve as temporary storage and channels for guiding the debris, effectively accommodating and expelling carbon particles and machining residues generated during discharge. This reduces the adverse effects of carbon buildup and enhances machining quality and efficiency. The experiment was divided into two main parts. The first part involved the milling of end-face grooves on the electrode. Various groove configurations and quantities were designed using 3D modeling, followed by toolpath editing and program generation via CAM software. The final electrodes were fabricated using a CNC milling machine. The second part consisted of EDM experiments using SCM440 medium carbon chromium molybdenum alloy steel as the workpiece material, simulating real machining conditions to evaluate performance. The discharge parameters included discharge voltage, current, pulse duration, jump height, and the use of a C-axis rotation function. This rotational motion helped continuously remove carbon deposits and debris during machining, thereby improving discharge stability. Experimental results showed that the electrode with a single groove achieved the best material removal rate (MRR) of 1.619% under a discharge voltage of 0.8 V, and exhibited the lowest electrode wear rate (EWR) of 0.068‰. In terms of surface roughness, the initial unmachined SCM440 surface had a roughness of Ra6.4 µm, which was improved to Ra 1.27 µm after machining with the single- groove electrode. These results indicate a significant advantage in both machining efficiency and surface quality. Overall, the single-groove electrode demonstrated the best performance among all electrode designs evaluated in this study |
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| Advisor Committee | |||
| Files | indicate in-campus access at 5 years and off-campus access at 5 years | ||
| Date of Defense | 2025-07-02 | Date of Submission | 2025-07-28 |