Deformation Behavior of AZ80 Wrought Magnesium Alloy at Cryogenic Temperatures
- Institute of Metal Research, Chinese Academy of Science, Shenyang, Liaoning, 110016 (China)
The influence of temperature on the deformation and failure behavior of AZ80 wrought Mg alloy has been examined from 77K to 298K. It is found that the yield strength (YS) and ultimate strength (UTS) are increasing with the temperature decreasing, while the elongation is decreasing especial between 213K and 143K. Based on the mechanical tests, observation of environmental scanning electron microscope (ESEM) and transmission electron microscope (TEM), it is proposed that the alloy deforms mainly by slips and twins, but undergoes different mechanism of cleavage in the range of testing temperature. At T>213K, the alloy ductility is higher because the dislocations could pass through twins but pile up at precipitate phase: Mg17Al12, which causes the crack nucleate. At T<143K, the alloy ductility is lower because the dislocation slip are suppressed greatly and dislocations pile up at twins, and cause crack nucleate and expand along twins quickly. At 143K<T<213K, the dislocations could run through some twins but pile up at others, and the alloy ductility drops sharply with decreasing temperature. The twins play an important role in deformation and failure of Mg alloys at cryogenic temperature.
- OSTI ID:
- 20800167
- Journal Information:
- AIP Conference Proceedings, Vol. 824, Issue 1; Conference: Cryogenic engineering conference, Keystone, CO (United States), 29 Aug - 2 Sep 2005; Other Information: DOI: 10.1063/1.2192349; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
- Country of Publication:
- United States
- Language:
- English
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