IN SITU TEM OBSERVATION OF EMBRITTLEMENT OF ALUMINUM ALLOY BY LIQUID METAL
LIU Xiaomin; SU Yanjing; HUANG Yizhong; CHU Wuyang(Department of Materials Physics; University of Science and Technology Beijing; Beijing 100083)Correspondent: LIU Xiaomin; Tel: (010)62332906; Fax:(010)62327283;E-mail: ljqiao@public.bta.net.cn)
Cite this article:
LIU Xiaomin; SU Yanjing; HUANG Yizhong; CHU Wuyang(Department of Materials Physics; University of Science and Technology Beijing; Beijing 100083)Correspondent: LIU Xiaomin; Tel: (010)62332906; Fax:(010)62327283;E-mail: ljqiao@public.bta.net.cn). IN SITU TEM OBSERVATION OF EMBRITTLEMENT OF ALUMINUM ALLOY BY LIQUID METAL. Acta Metall Sin, 1998, 34(10): 1021-1027.
Abstract The liquid metal-induced embrittlement (LME) of 7075 aluminum alloy was investigated by using a special constant deflection device. The change in dislocation configuration ahead of a loaded crack tip for 7075 aluminum alloy before and after adsorping of Hg+3%Ga atoms, and the initiation of liquid metal-induced microcrack have been observed in TEM. The results showed that chemisorption of liquid metal atoms could facilitate dislocation emission,multiplication and motioll. When the chemisorption - facilitating dislocation emission and motionreach to a critical condition, a microcrack will initiate in dislocation free zone (DFZ) or at the crack tip, and propagate in cleavage mode.
1 Nicholas M G, Old C F. J Mater Sci, 1979; 14:1 2 Kelley M J, Stoloff N S. Metall Trans, 1975; 6A: 159 3 Lynch S P. Acta Metall, 1988; 36: 2639 4 Kargol J A, Albrighy D L. Metall Trans, 1977; 8A: 27 5 刘晓敏,乔利杰,褚武扬.金属学报,1998;34:615(Liu X M, Qiao L J, Chu W Y. Acta Metall Sin, 1998; 34: 615) 6 谷飚,张静武,万发荣,褚武扬.金属学报,1995;31:A156(Gu B, Zhang J W, Wan F R, Chu W Y. Acta Metall Sin, 1995; 31: A156) 7 高克玮,王燕斌,褚武扬.金属学报,1995;31:8477(Gao K W, Wang Y B, Chu W Y. Acta Metall Sin, 1995; 31: B477) 8 Su Y J, Wang Y B, Chu W Y. Sci Chin, 1997; 40E: 875 9 Gao K W, Wang Y B, Chu W Y. Sci Chin, 1995; 38A: 1501 10 Li M D, Lu H, Zhang T C, Chu W Y. Sci Chin, 1997; 40E: 530 11 Gu B, Gao K W, Huang Y Z, Chu W Y. Sci Chin, 1997; 40E: 235 12 Ohr S M. Mater Sci Eng, 1985; 72: 1 13 Cherepanov G P. Mechanics of Brittle Fracture. New York: McGraw-Hill, 1979: 29 14 Dewald D K, Lee T C, Robertson I M, Birnbaum H K. Scr Metall, 1989; 23: 1307 15 Zhu T, Yang W, Guo T. Acta Maten 1996; 44: 3049 16 Suo Z, Yang W, Shih C F. Acta Metall Maten 1995; 41: 1551 17 褚武扬.氢损伤与滞后断裂.北京:冶金工业出版社,1988:261(Chu W Y. Hvdmpen Damage and Hydmpen-Induced Cracbng. Beijing: The Metallurgy Industry Press,1988: 261) 18 褚武扬.断裂力学基础.北京:科学出版社,1979:35 (Chu W Y. Fundamental of Fracture Mechanism. Beijing: Science Press, 1979: 35)
