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Title: Large plasticity in magnesium mediated by pyramidal dislocations

Abstract

Lightweight magnesium alloys are attractive as structural materials for improving energy efficiency in applications such as weight reduction of transportation vehicles. One major obstacle for widespread applications is the limited ductility of magnesium, which has been attributed to c + a dislocations failing to accommodate plastic strain. We demonstrate, using in situ transmission electron microscope mechanical testing, that c + a dislocations of various characters can accommodate considerable plasticity through gliding on pyramidal planes. We found that submicrometer-size magnesium samples exhibit high plasticity that is far greater than for their bulk counterparts. Small crystal size usually brings high stress, which in turn activates more c + a dislocations in magnesium to accommodate plasticity, leading to both high strength and good plasticity.

Authors:
ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [3]; ORCiD logo [4]; ORCiD logo [4]; ORCiD logo [5]; ORCiD logo [6]; ORCiD logo [7]; ORCiD logo [1]
  1. Center for Advancing Materials Performance from the Nanoscale (CAMP-Nano) and Hysitron Applied Research Center in China (HARCC), State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an 710049, People’s Republic of China.
  2. College of Science, Xi’an University of Science and Technology, Xi’an 710054, People’s Republic of China.
  3. MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, School of Science, Xi’an Jiaotong University, Xi’an 710049, People’s Republic of China.
  4. Department of Chemical and Materials Engineering, University of Nevada, Reno, NV 89557, USA.
  5. Departments of Nuclear Science and Engineering and Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
  6. Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD 21218, USA.
  7. Department of Materials Science and Engineering, Monash University, Melbourne, Victoria, 3800, Australia., International Joint Laboratory for Light Alloys (Ministry of Education), College of Materials Science and Engineering, Chongqing University, Chongqing 400044, People’s Republic of China.
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1531038
Grant/Contract Number:  
FG02-16ER46056
Resource Type:
Published Article
Journal Name:
Science
Additional Journal Information:
Journal Name: Science Journal Volume: 365 Journal Issue: 6448; Journal ID: ISSN 0036-8075
Publisher:
American Association for the Advancement of Science (AAAS)
Country of Publication:
United States
Language:
English

Citation Formats

Liu, Bo-Yu, Liu, Fei, Yang, Nan, Zhai, Xiao-Bo, Zhang, Lei, Yang, Yang, Li, Bin, Li, Ju, Ma, Evan, Nie, Jian-Feng, and Shan, Zhi-Wei. Large plasticity in magnesium mediated by pyramidal dislocations. United States: N. p., 2019. Web. doi:10.1126/science.aaw2843.
Liu, Bo-Yu, Liu, Fei, Yang, Nan, Zhai, Xiao-Bo, Zhang, Lei, Yang, Yang, Li, Bin, Li, Ju, Ma, Evan, Nie, Jian-Feng, & Shan, Zhi-Wei. Large plasticity in magnesium mediated by pyramidal dislocations. United States. doi:10.1126/science.aaw2843.
Liu, Bo-Yu, Liu, Fei, Yang, Nan, Zhai, Xiao-Bo, Zhang, Lei, Yang, Yang, Li, Bin, Li, Ju, Ma, Evan, Nie, Jian-Feng, and Shan, Zhi-Wei. Thu . "Large plasticity in magnesium mediated by pyramidal dislocations". United States. doi:10.1126/science.aaw2843.
@article{osti_1531038,
title = {Large plasticity in magnesium mediated by pyramidal dislocations},
author = {Liu, Bo-Yu and Liu, Fei and Yang, Nan and Zhai, Xiao-Bo and Zhang, Lei and Yang, Yang and Li, Bin and Li, Ju and Ma, Evan and Nie, Jian-Feng and Shan, Zhi-Wei},
abstractNote = {Lightweight magnesium alloys are attractive as structural materials for improving energy efficiency in applications such as weight reduction of transportation vehicles. One major obstacle for widespread applications is the limited ductility of magnesium, which has been attributed to 〈 c + a 〉 dislocations failing to accommodate plastic strain. We demonstrate, using in situ transmission electron microscope mechanical testing, that 〈 c + a 〉 dislocations of various characters can accommodate considerable plasticity through gliding on pyramidal planes. We found that submicrometer-size magnesium samples exhibit high plasticity that is far greater than for their bulk counterparts. Small crystal size usually brings high stress, which in turn activates more 〈 c + a 〉 dislocations in magnesium to accommodate plasticity, leading to both high strength and good plasticity.},
doi = {10.1126/science.aaw2843},
journal = {Science},
number = 6448,
volume = 365,
place = {United States},
year = {2019},
month = {7}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record
DOI: 10.1126/science.aaw2843

Citation Metrics:
Cited by: 17 works
Citation information provided by
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