最新色国产精品精品视频,中文字幕日韩一区二区不卡,亚洲有码转帖,夜夜躁日日躁狠狠久久av,中国凸偷窥xxxx自由视频

+高級檢索
氧化鑭彌散強(qiáng)化鉬合金裂紋擴(kuò)展的TEM原位觀察
DOI:
作者:
作者單位:

作者簡介:

通訊作者:

中圖分類號:

基金項(xiàng)目:

國家自然科學(xué)基金（50801051）和國家高技術(shù)研究發(fā)展計(jì)劃（2008AA031001）資助


TEM in situ Observation of Crack Propagation in Lanthanum Oxide Dispersion Strengthened Molybdenum Alloy
Author:
Affiliation:

Fund Project:

  • 摘要
    • |
  • 圖/表
    • |
  • 訪問統(tǒng)計(jì)
    • |
  • 參考文獻(xiàn)
    • |
  • 相似文獻(xiàn)
    • |
  • 引證文獻(xiàn)
    • |
  • 資源附件
    • |
  • 文章評論
    摘要:

    采用透射電子顯微鏡動態(tài)拉伸技術(shù)對氧化鑭彌散強(qiáng)化鉬合金的裂紋擴(kuò)展過程進(jìn)行原位觀察。發(fā)現(xiàn)裂紋的擴(kuò)展模式受基體晶粒尺寸與氧化鑭顆粒的形狀和尺寸影響。裂紋尖端遇到非常細(xì)小的晶粒時會發(fā)生沿晶界擴(kuò)展；裂紋尖端遇到棒狀微米級粗大氧化鑭顆粒時，裂紋穿過氧化鑭顆粒擴(kuò)展；遇到橢球狀亞微米級氧化鑭顆粒時，裂紋越過氧化鑭顆粒擴(kuò)展，并發(fā)生裂紋擴(kuò)展方向的偏轉(zhuǎn)；而當(dāng)裂紋擴(kuò)展到細(xì)小的球狀納米級氧化鑭顆粒時會被阻止，裂紋以“Z”字型或跨接的方式繼續(xù)擴(kuò)展。根據(jù)實(shí)驗(yàn)結(jié)果從裂紋擴(kuò)展方式和能量耗散角度對氧化鑭彌散鉬合金的細(xì)晶增韌和顆粒增韌機(jī)制進(jìn)行分析和討論。

    Abstract:

    The processes of crack propagation in the La2O3-dispersed-strengthened molybdenum alloy were studied by in situ observation of transmission electron microscope. The results show that the paths of crack propagation in the alloy are dependent on the grain size of the molybdenum matrix and the shape and size of La2O3 particles. The crack propagates along the grain boundary of the matrix when it meets very fine molybdenum particles; the crack directly passes through the La2O3 particles to propagate when it meets micron-sized coarse rod-shaped La2O3 particles; the crack detours the particles and deflects when it meets sub-micron-sized ellipsoid-shaped La2O3 particles; the crack is pinned and then goes on propagating in zigzag or by bridging when it meets the nanosized fine and spherical La2O3 particles. Based on these experimental results, the mechanism of fine-grain toughening and particle-toughening of La2O3-dispersed- strengthened molybdenum were discussed from the aspect of the crack propagation paths and energy dissipation.

    參考文獻(xiàn)
    相似文獻(xiàn)
    引證文獻(xiàn)
引用本文

張國君,劉 剛,孫院軍,孫 軍.氧化鑭彌散強(qiáng)化鉬合金裂紋擴(kuò)展的TEM原位觀察[J].稀有金屬材料與工程,2010,39(5):828~831.[Zhang Guojun, Liu Gang, Sun Yuanjun, Sun Jun. TEM in situ Observation of Crack Propagation in Lanthanum Oxide Dispersion Strengthened Molybdenum Alloy[J]. Rare Metal Materials and Engineering,2010,39(5):828~831.]
DOI：[doi]

復(fù)制
文章指標(biāo)
  • 點(diǎn)擊次數(shù):
  • 下載次數(shù):
  • HTML閱讀次數(shù):
  • 引用次數(shù):
歷史
  • 收稿日期:2009-05-15
  • 最后修改日期:
  • 錄用日期:
  • 在線發(fā)布日期:
  • 出版日期: