請用此 Handle URI 來引用此文件:
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/90195
標題: | 探討陶瓷基鋁碳化矽於電化學加工反應層之研究 Study on the Reaction Layer Generated during Electrochemical Machining of Ceramic-based Aluminum Silicon Carbide |
作者: | 楊宗儫 Tsung-Hao Yang |
指導教授: | 蔡曜陽 Yao-Yang Tsai |
關鍵字: | 電化學加工,鋁碳化矽,過度反應區,反應層,X射線光電子能譜學, Electrochemical Machining,Aluminum Silicon Carbide,Excessive Reaction Area,Reaction Layer,X-ray Photoelectron Spectroscopy, |
出版年 : | 2023 |
學位: | 碩士 |
摘要: | 電化學磨削(electrochemical grinding)在加工鋁碳化矽(aluminum silicon carbide)複合材料的過程中,化學能力與機械能力之間的匹配對於加工結果的優劣存在至關重大的影響。為了降低電極周圍之過度化學反應結果,必須適當抑制電化學反應時間,意即磨棒進給率必須提升至一定數值。然而,其所匹配之高進給率會導致磨棒主軸過載、工件表面產生燒痕、磨棒嚴重毀損等負面效應。另外,於電化學加工領域中,目前鮮少有研究針對加工鋁碳化矽過程中所產生的反應層進行探討。因此本研究首先透過電化學加工鋁碳化矽,探討參數與加工結果之間的關聯與變化趨勢。之後針對加工後的鋁碳化矽進行材料分析,以解釋反應層於電化學磨削中的角色。最後,針對過度反應範圍其硬度分布進行探討。
研究過程挑選電壓與電極移動率兩參數進行全因子試驗,並分析參數與加工結果之間的關係,其中加工結果包含過度反應長(excessive reaction length)、過度反應單邊寬(unilateral width of excessive reaction)、反應深度差以及深-反應距離差比(the ratio of depth to difference about reaction distance)。材料分析過程中藉由高能量化學分析電子能譜儀調查鋁碳化矽反應前後材料成分之變化,並使用掃描式電子顯微鏡、微小維克氏硬度計、四點探針電阻量測儀等儀器驗證反應層之材料性質。於後續分析過度反應範圍與硬度分布階段,探討固定電極與電極移動兩情況所生成的反應層其硬度分布之差異。 實驗分析結果表示— 雖然絕緣調整對於電化學加工鋁碳化矽所生成之過度反應區無法顯著性地抑制,但其能令過度反應範圍變得更對稱且有效改善不穩定因素所造成的負面影響,證實其為控制過度反應區形狀的方式之一。此外,透過回歸分析求得經絕緣調整之電化學加工於電壓為24V的回歸方程式,可藉其推測其他電極移動率下所獲得之加工結果。材料量測結果顯示,電化學加工鋁碳化矽時所形成的反應層是由鬆散碳化矽結構包含少量鋁和矽的氧化物以及鋁的氫氧化物所組成,並證實反應層其結構脆弱特性主要是來自電化學的作用,而其需經由外力去除,因此可知電化學磨削中的電化學作用與磨削兩者是需要相輔相成的。最後,針對過度反應範圍之硬度分布分析結果,得出電極中心垂直投影處電化學反應較為劇烈此事且固定電極之反應層硬度大於移動電極之反應層硬度,推測電力線具推移的特性,面向電極行進方向的電力線相較背對電極行進方向的電力線還要密集,因此該區域的反應較劇烈。 The quality of aluminum silicon carbide composites obtained through electrochemical grinding is heavily influenced by the balance between chemical and mechanical capabilities. To mitigate excessive chemical reaction around the electrode, the electrochemical reaction time must be properly controlled, requiring an increase in the feed rate of the grinding wheel. However, using a high feed rate for this purpose can lead to negative consequences such as spindle overload, workpiece surface burns, and severe damage to the grinding tool. Additionally, there is a lack of research on the reaction layer formed during the electrochemical machining of aluminum silicon carbide.The objective of this study is to explore the correlation and trends between parameters and machining results during electrochemical machining of aluminum silicon carbide. Furthermore, material analysis is conducted on the machined aluminum silicon carbide to elucidate the role of the reaction layer in electrochemical grinding. Finally, the hardness distribution of the excessive reaction area is examined. During the research process, a full factorial experiment is carried out, investigating the effects of voltage and electrode moving rate on machining results, including excessive reaction length, unilateral width of excessive reaction, difference in reaction depth, and the ratio of depth to difference about reaction distance. Material analysis is conducted using hard X-ray photoelectron spectroscopy to examine changes in material composition before and after the reaction. The material properties of the reaction layer are verified using scanning electron microscopy, micro-Vickers hardness testing, and four-point probe resistance measurement. The differences in hardness distribution of the excessive reaction area, with fixed and moving electrodes, are also studied. The experimental analysis reveals that insulation adjustment does not significantly suppress excessive reaction area during the electrochemical machining of aluminum silicon carbide. However, it does make the excessive reaction area more symmetrical and properly mitigates the negative effects caused by unstable factors, confirming it as one of the ways to control the shape of excessive reaction area. Regression analysis is also employed to create a regression equation for electrochemical machining with a voltage of 24V after insulation adjustment, which can be used to predict the results obtained at other electrode moving rates. Material measurement results indicate that the reaction layer formed during the electrochemical machining of aluminum silicon carbide consists of loosely packed silicon carbide structures, small amounts of aluminum and silicon oxides, and aluminum hydroxides. This confirms the fragile nature of the reaction layer, primarily caused by electrochemical action, necessitating external force for removal. It highlights the complementary relationship between electrochemical action and grinding in electrochemical grinding. Finally, based on the analysis of the hardness distribution of the excessive reaction area, it is found that more intense electrochemical reactions occur at the center of the electrode's vertical projection, and the hardness of the reaction layer with a fixed electrode is higher than that with a moving electrode, suggesting that the movement of power lines plays a role. Power lines moving toward the electrode direction are more concentrated compared to those moving away from the electrode direction, resulting in more intense reactions in that area. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/90195 |
DOI: | 10.6342/NTU202303704 |
全文授權: | 同意授權(限校園內公開) |
顯示於系所單位: | 機械工程學系 |
文件中的檔案:
檔案 | 大小 | 格式 | |
---|---|---|---|
ntu-111-2.pdf 授權僅限NTU校內IP使用(校園外請利用VPN校外連線服務) | 9.34 MB | Adobe PDF | 檢視/開啟 |
系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。