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Journal of Materials Engineering and Performance

, Volume 28, Issue 11, pp 6692–6703 | Cite as

Microstructure, Texture, and Mechanical Properties of Continuously Extruded and Rolled AZ31 Magnesium Alloy Sheets

  • Lili GuoEmail author
  • Rong Fu
  • Jiuyang Pei
  • Jianqiang Wang
  • Hongyang Zhao
  • Baoyun Song
  • Zhongchun ChenEmail author
Article
  • 62 Downloads

Abstract

It is difficult to fabricate magnesium alloy sheets at room temperature due to their hexagonal close-packed structure. In this paper, we proposed a new process that can be used to fabricate AZ31 magnesium alloy sheets with fine-grained microstructure and good mechanical properties. AZ31 magnesium alloy sheets with dimensions of 160 mm × 8 mm were obtained successfully by a continuous extrusion technique. The extruded sheets were then rolled by two different rolling routes, Route 1: the extruded sheet was heated at 350 °C and then rolled without heating of rolls and Route 2: the sheet was rolled without any previous heating by heating rolls at 280 °C. The microstructure and texture evolution as well as mechanical properties of the continuously extruded and rolled sheets were examined experimentally. The magnesium alloy sheets with relatively fine grains of 4.5-8.3 µm were obtained by continuous extrusion followed by rolling processes. The tensile strength of continuously extruded AZ31 Mg alloy sheets can be effectively increased by rolling using heating rolls (Route 2), while the ductility was enhanced by rolling heated sheets (Route 1). The mixed microstructure, consisting of refined DRX grains and deformed grains, contributes to enhancement in tensile strength of the sheet samples rolled by Route 2 due to grain-boundary strengthening and work hardening. Lower temperature and larger rolling reduction are two main factors for improving the tensile strength of AZ31magnesium alloy sheets.

Keywords

continuous extrusion magnesium alloys microstructure rolling tensile properties 

Notes

Acknowledgments

This work was supported partly by the National Natural Science Foundation of China (Grant Number: 51401043) and Liaoning Provincial Nature Science Foundation of China (Grant Number: 2019-MS-035). The authors would like to acknowledge the help from the members of BAOSTEEL, China.

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Copyright information

© ASM International 2019

Authors and Affiliations

  1. 1.Engineering Research Center of Continuous Extrusion, Ministry of EducationDalian Jiaotong UniversityDalianChina
  2. 2.School of Materials Science and EngineeringUniversity of Science and Technology LiaoningAnshanChina
  3. 3.Dalian Konform Technical Company LimitedDalianChina
  4. 4.Department of Mechanical and Aerospace Engineering, Graduate School of EngineeringTottori UniversityTottoriJapan

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