An Experimental Study of Mg Aggregation in AA5754 Alloys byPositron Annihilation Spectroscopy
HUANG Chang-Hong 1,2, MA Li 1,2, CHEN Zhi-Quan 1,2, WANG Zhu 1,2, WANG Xiao-Wei 3, ZHANG Hong-Yan 4
1Department of Physics, Wuhan University, Wuhan 430072
2Hubei Nuclear Solid Physics Key Laboratory, Wuhan University, Wuhan 430072
3Shenyang National Laboratory of Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016
4Department of MIME, University of Toledo, Toledo, OH 43606, USA
An Experimental Study of Mg Aggregation in AA5754 Alloys byPositron Annihilation Spectroscopy
1Department of Physics, Wuhan University, Wuhan 430072
2Hubei Nuclear Solid Physics Key Laboratory, Wuhan University, Wuhan 430072
3Shenyang National Laboratory of Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016
4Department of MIME, University of Toledo, Toledo, OH 43606, USA
摘要Defects in an AA5754 (Al-3.0%Mg) alloy are investigated by coincidence Doppler broadening spectroscopy and positron lifetime spectroscopy. The results indicate enhancement of positron trapping by Mg atoms in this Al--Mg alloy after quenching treatment at 623K, which may be due to the formation of vacancy-Mg complexes or the aggregation of Mg near the vacancy sites. It is speculated that the aggregation of Mg atoms in the moderate temperature range is responsible for cracking in spot welding of AA5754 alloys.
Abstract：Defects in an AA5754 (Al-3.0%Mg) alloy are investigated by coincidence Doppler broadening spectroscopy and positron lifetime spectroscopy. The results indicate enhancement of positron trapping by Mg atoms in this Al--Mg alloy after quenching treatment at 623K, which may be due to the formation of vacancy-Mg complexes or the aggregation of Mg near the vacancy sites. It is speculated that the aggregation of Mg atoms in the moderate temperature range is responsible for cracking in spot welding of AA5754 alloys.
HUANG Chang-Hong;MA Li;CHEN Zhi-Quan;WANG Zhu;WANG Xiao-Wei;ZHANG Hong-Yan. An Experimental Study of Mg Aggregation in AA5754 Alloys byPositron Annihilation Spectroscopy[J]. 中国物理快报, 2007, 24(2): 546-548.
HUANG Chang-Hong, MA Li, CHEN Zhi-Quan, WANG Zhu, WANG Xiao-Wei, ZHANG Hong-Yan. An Experimental Study of Mg Aggregation in AA5754 Alloys byPositron Annihilation Spectroscopy. Chin. Phys. Lett., 2007, 24(2): 546-548.
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2007, Vol. 24 
