Structural refinement and nanomechanical response of laser remelted Al-Al2Cu lamellar eutectic

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:706

Article

Lei, Qian¹  Ramakrishnan, Bhupendera Prashanth²  Wang, Shujuan¹  Wang, Yichen¹  Mazumder, Jyotirmoy^1,2  Misra, Amit¹ 

[1] Univ Michigan, Coll Engn, Dept Mat Sci & Engn, Ann Arbor, MI 48109 USA

[2] Univ Michigan, Coll Engn, Dept Mech Engn, Ann Arbor, MI 48109 USA

关键词: Al-Cu alloys;    Eutectic alloy;    Microstructure;    Plasticity;   

DOI  :  10.1016/j.msea.2017.08.105

来源: Elsevier

【 摘 要 】

Laser remelting was employed to refine the interlamellar spacing (lambda) to approximately 30 nm on an arc -cast Al 32.7 wt%Cu eutectic. lambda scaled with A '(h)(-0.25) where.h is the distance from the trace bottom, and A' is a factor dependent on laser processing conditions. A' increased with the laser power (at a constant spot diameter) but decreased with the spot diameter (at a constant laser power). The nanoindentation measured hardness increased up to 4.68 GPa with decreasing interlamellar spacing, following the Hall-Petch relation. The as -cast eutectics showed microcracks around indents, while cracking was suppressed in the laser remelted nanoscale eutectics. A dislocation theory based mechanism is proposed for the enhanced plastic co -deformation of fine scale laser remelted Al-Al2Cu eutectics.

【 授权许可】

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