Fabrication of FCC-type magnesium alloys aiming for both easy workability and lightness

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K05149
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 26050:Material processing and microstructure control-related
• Research Institution: Chiba University
• Principal Investigator: Itoi Takaomi 千葉大学, 大学院工学研究院, 教授 (50333670)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: マグネシウム / インジウム / 面心立法構造 / 圧延 / 難燃性

Outline of Final Research Achievements

The Mg0.1In0.9 phase with FCC structure was formed in Mg-In and Mg-Al-In alloys. The LCR (Limiting Cold-Rolling ratio) at room temperature tended to increase with increasing area fraction of the Mg0.1In0.9 phase, and the LCR achieved 80% for the single Mg0.1In0.9 phase in both alloys. Since the Mg0.1In0.9 phase dissolves about 5 mol% of Al, substituting Al for In in the Mg-In alloy was effective in reducing density. The density of the Mg80Al7In13 (mol%) alloy is 2.60g/cm3, which is lower than that of Al, and the LCR showed 49%. When a small amount of Ca or Y was added to the Mg-Al-In alloy, the additional elements formed oxides on the surface on the molten alloy during combustion, showing excellent flame retardancy.

Free Research Field

材料工学

Academic Significance and Societal Importance of the Research Achievements

輸送機器の軽量化は直接的に燃費の向上につながるため、Mg合金は自動車や鉄道および航空機へ仕様が期待されている。しかし、Mgは六方晶構造であることから室温での加工性がAlなどの軽金属と比較して劣る。本研究ではこれまで試みられていない、面心立法構造のMg合金を作製し、密度の低下に配慮しながらIn添加によるFCC構造への変化を明らかにして室温での圧延特性を改善したところに意義がある。さらに少量のCaやYの添加により難燃性についても改善を試み、より広範の輸送機器への活用の可能性を試みたところを特徴とする。