中大機構典藏-NCU Institutional Repository-提供博碩士論文、考古題、期刊論文、研究計畫等下載:Item 987654321/50164
English  |  正體中文  |  简体中文  |  全文笔数/总笔数 : 81570/81570 (100%)
造访人次 : 46926452      在线人数 : 674
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
搜寻范围 查询小技巧:
  • 您可在西文检索词汇前后加上"双引号",以获取较精准的检索结果
  • 若欲以作者姓名搜寻,建议至进阶搜寻限定作者字段,可获得较完整数据
  • 进阶搜寻


    jsp.display-item.identifier=請使用永久網址來引用或連結此文件: http://ir.lib.ncu.edu.tw/handle/987654321/50164


    题名: Study of gas film quality in electrochemical discharge machining
    作者: Cheng,CP;Wu,KL;Mai,CC;Yang,CK;Hsu,YS;Yan,BH
    贡献者: 機械工程學系
    关键词: CHEMICAL ENGRAVING SACE;MATERIAL REMOVAL;GRAVITY-FEED;GLASS;MECHANISM;ECDM;MODEL;TIME
    日期: 2010
    上传时间: 2012-03-27 17:05:06 (UTC+8)
    出版者: 國立中央大學
    摘要: Electrochemical Discharge Machining (ECDM) has been demonstrated to be an alternative spark-based micromachining method for fabricating microholes and microchannels in non-conductive brittle materials. However, the mechanism for attaining accurate control of the contour shape and dimensions remains to be explored. In ECDM process, the gas film on the electrode surface is used as the dielectric medium required for discharge generation. Quality of gas film is the dominant factor that determines the machining qualities such as geometric accuracy, surface roughness and repeatability. Nevertheless, it is difficult to assess the gas film quality of ECDM. In this study, current signals and machined contours were taken as indexes of gas film quality. Experimental results showed that a stable and dense gas film could be obtained when the applied voltage exceeded the critical voltage and reached a specific level, which is called the "transition voltage" in this study. At the transition voltage, a stable electrochemical discharge activity could be generated, thus producing the smallest deviation of contour dimensions. Moreover, when the drilling process reached a certain critical depth, bubbles inside the hole could not easily escape. In order to reduce the interface energy between bubbles, a thicker gas film is formed at the hole entrance, resulting in unstable discharge performance that undermined machining results. In summary, information provided by current signals can shed light on the changes in gas film structure, which serve as useful reference for varying process parameters to achieve better efficiency and accuracy. (C) 2010 Elsevier Ltd. All rights reserved.
    關聯: INTERNATIONAL JOURNAL OF MACHINE TOOLS & MANUFACTURE
    显示于类别:[機械工程學系] 期刊論文

    文件中的档案:

    档案 描述 大小格式浏览次数
    index.html0KbHTML390检视/开启


    在NCUIR中所有的数据项都受到原著作权保护.

    社群 sharing

    ::: Copyright National Central University. | 國立中央大學圖書館版權所有 | 收藏本站 | 設為首頁 | 最佳瀏覽畫面: 1024*768 | 建站日期:8-24-2009 :::
    DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - 隱私權政策聲明