Regulating twin boundary mobility to develop high damping and high strength magnesium alloys

2019 Fiscal Year Final Research Report

• Project/Area Number: 18K14024
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 26050:Material processing and microstructure control-related
• Research Institution: Tohoku University
• Principal Investigator: CUI YUJIE 東北大学, 金属材料研究所, 特任助教 (30796214)
• Project Period (FY): 2018-04-01 – 2020-03-31
• Keywords: Magnesium / Twin boundary / Pre-strain / Al atoms / Segregation

Outline of Final Research Achievements

Twinning is an important deformation mode in Mg alloys. Twin can grow and shrink. The reciprocating movements of twin boundaries have a significant effect on mechanical properties of Mg alloys. The effects of pre-strain and Al atoms on twin boundary motion in Mg and its alloys were investigated. Smaller twins with lower pre-strain exhibit higher twin boundary mobility than larger twins. The Al atoms were found to restrict both twin growth and detwinning.
Our findings indicate that altering pre-strain and alloying element concentration is an effective way to tailor twin boundary mobility, providing a basis for developing Mg alloys with high strength and high damping capacity.

Free Research Field

Material processing

Academic Significance and Societal Importance of the Research Achievements

双晶界面移動度の制御に基づいて、一方で、双晶界面を移動させることにより、Mg合金の減衰能力を高めることができる。一方、双晶界面を固定化することでMg合金の強度を向上させることができる。この研究により、Mg合金の変形メカニズムに関する理解が大幅に向上させ、新たな高強度と高減衰能力のMg合金開発を提案した。