English  |  正體中文  |  简体中文  |  全文筆數/總筆數 : 64745/64745 (100%)
造訪人次 : 20452099      線上人數 : 362
RC Version 7.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
搜尋範圍 查詢小技巧:
  • 您可在西文檢索詞彙前後加上"雙引號",以獲取較精準的檢索結果
  • 若欲以作者姓名搜尋,建議至進階搜尋限定作者欄位,可獲得較完整資料
  • 進階搜尋


    請使用永久網址來引用或連結此文件: http://ir.lib.ncu.edu.tw/handle/987654321/2083


    題名: 具變形誘導異向性質之降伏曲面與材料函數的內涵模式;Endochronic Model of Yield Surface and Material Function Accounting for Deformation Induced Anisotropy
    作者: 林希彥;Hsi-Yen Lin
    貢獻者: 機械工程研究所
    關鍵詞: 循環應變硬化;內涵理論;材料函數;記憶消除;material function;cyclic strain hardening;endochronic theory;erasure of memory
    日期: 2006-12-26
    上傳時間: 2009-09-21 11:37:58 (UTC+8)
    出版者: 國立中央大學圖書館
    摘要: 本文主要探討內涵塑性理論之材料函數(material function) ,藉由適當地選擇材料函數中之材料參數,可將該材料函數區分成六種類型之態樣,以期更適切地描述材料在非對稱振幅循環負載下之材料行為,包括包辛格效應(Bauschinger effect)、循環硬化(軟化)、應力穩定飽和(saturation)、循環應力峰值(peek stress)的變化以及材料記憶消除(erasure of memory)行為,並以Shiao [1]及Lamba and Sidebottom [2]之實驗結果驗證本文之材料函數模式;另外本文提出一組與隨後降伏曲面(sequencent yield surface)之形狀特徵比 (aspect ratio)相關的材料函數,建立一降伏曲面的內涵模式,藉以模擬材料在小變形(small pre-strain range)下因變形誘導異向性(deformation induced anisotropy)而表現在其隨後降伏曲面呈前凸後扁狀( sharp front and blunt rear)的演化行為,另以Wu and Yeh [3] 對AISI 304 不銹鋼施以軸向、扭向以及軸扭雙向應變作用之實驗結果驗證本文之降伏曲面模式;採用本文之材料函數及降伏曲面模式預測材料循環塑性行為及降伏曲面的演化行為與實驗結果比對相當吻合。 In this article, a material function of endochronic theory is proposed for investigating the plastic behaviors of material. Depending on the material parameters properly chosen, the present model can be classified into six categories, and is appropriate for describing various materials behaving cyclic strain hardening inherently with respect to the deformation history. Experimental verification of the theory was demonstrated using the experimental results of Shiao [1] and Lamba and Sidebottom [2]. The theory is in good agreement with experimental results obtained by Shiao [1] through comparing the stress-strain hysteresis loops of SAE 4340 steel under axisymmetrically cyclic loading condition with various amplitudes. In addition, the present model is shown to be capable of describing the behavior of erasure of memory of materials, as experimentally observed by Lamba and Sidebottom [2]. In addition, an endochronic model of yield surface is proposed. Based on this model, the yield surface is simulated such that the forward and rear parts of the yield surface are described by different ellipses which are characterized by corresponding aspect ratio functions, respectively. Verification of the endochronic theory used the experimental results of yield surfaces obtained by Wu and Yeh [3] for AISI 304 stainless steel. The experiments were performed cyclically under uniaxial, torsional, and combined axial-torsional loading conditions. The result has shown that the agreement between the prediction and experiments is quite satisfactory. In addition to the distortion of the yield surface plastically behaving a sharp front accompanied by a blunt rear, the anisotropic kinematic hardening effect has been addressed in this investigation.
    顯示於類別:[機械工程研究所] 博碩士論文

    文件中的檔案:

    檔案 大小格式瀏覽次數
    0KbUnknown711檢視/開啟


    在NCUIR中所有的資料項目都受到原著作權保護.

    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 ©   - 回饋  - 隱私權政策聲明