Dynamic Deformation Behaviour and Microstructural Evolution of High-Strength Weldable Aluminum Scandium (Al-Sc) Alloy

この論文にアクセスする

この論文をさがす

著者

抄録

A compressive split-Hopkinson pressure bar is used to investigate the dynamic deformation behaviour, fracture characteristics and microstructural evolution of high-strength weldable aluminum scandium (Al-Sc) alloy at strain rates ranging from 1.3×10<SUP>3</SUP> s<SUP>−1</SUP> to 5.9×10<SUP>3</SUP> s<SUP>−1</SUP> under room temperature conditions. The stress-strain curves reveal that the dynamic mechanical behaviour response of the Al-Sc alloy is highly sensitive to both the strain and the strain rate. As the strain rate increases, the flow stress, work hardening rate and strain rate sensitivity all increase, but the fracture strain and activation volume decrease. The Zerilli-Armstrong FCC constitutive model is applied to describe the high strain rate plastic behaviour of the Al-Sc alloy. A good agreement is found between the predicted flow response and the actual response at all values of the applied strain rate. The Al-Sc alloy specimens fracture primarily as a result of a localised shearing effect. Scanning electron microscopy observations indicate that the fracture features are characterised by a transgranular dimple-like structure. The density and depth of the dimples decrease with increasing strain rate. Transmission electron microscopy observations reveal the presence of Al<SUB>3</SUB>Sc particles in the matrix and at the grain boundaries. These particles prevent dislocation motion and therefore prompt a significant strengthening effect. The microstructural observations also reveal that the dislocation density and degree of dislocation tangling increase with increasing strain rate. The variations observed in the dislocation cell structure reflect differing degrees of strain rate sensitivity and activation volume and are found to be consistent with the observed stress-strain response of the Al-Sc alloy.

収録刊行物

  • Materials transactions  

    Materials transactions 49(6), 1284-1293, 2008-06-01 

    The Japan Institute of Metals and Materials

参考文献:  25件

参考文献を見るにはログインが必要です。ユーザIDをお持ちでない方は新規登録してください。

各種コード

  • NII論文ID(NAID)
    10021147410
  • NII書誌ID(NCID)
    AA1151294X
  • 本文言語コード
    ENG
  • 資料種別
    ART
  • ISSN
    13459678
  • NDL 記事登録ID
    9519130
  • NDL 雑誌分類
    ZP41(科学技術--金属工学・鉱山工学)
  • NDL 請求記号
    Z53-J286
  • データ提供元
    CJP書誌  NDL  J-STAGE 
ページトップへ