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DOI QR Code

이속 압연된 마그네슘 합금의 미세조직 및 기계적 물성에 미치는 가공 변수의 영향

Effects of Processing Conditions on Microstructure and Mechanical Properties of Mg Alloy Deformed by Differential Speed Rolling

  • 투고 : 2017.09.21
  • 심사 : 2017.12.27
  • 발행 : 2018.02.01

초록

This paper outlines the research findings on the microstructure and mechanical properties of AZ31 Mg alloy fabricated by differential speed rolling (DSR) with respect to processing variables such as temperature, roll speed ratio (RSR), and deformation route. The resultant microstructure of the sample, deformed by 2-pass DSRs at 473 K, comprised finer grains with more uniform distribution than those at 573 and 623 K. This was due to active recrystallization, which was expected to appear during DSR at temperatures higher than 573 K. When the sample was deformed via DSR with RSR of 1:4 for the upper and lower rolls at 453 K, the values of yield and ultimate tensile strength were observed to be higher than their counterpart with RSR of 1:1. The application of sample rotation around the longitudinal axis would give rise to an excellent combination of tension strength (~330 MPa) and ductility (~20 %) at ambient temperatures. This is discussed based on its uniform fine grained structure and the softening of basal texture.

키워드

참고문헌

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