Optimal design of 2D cell type structure of magnesium alloys considering mechanical characteristics induced by deformation twins

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K03781
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 18010:Mechanics of materials and materials-related
• Research Institution: Okayama University of Science
• Principal Investigator: Shimizu Ichiro 岡山理科大学, 工学部, 教授 (10263625)
• Co-Investigator(Kenkyū-buntansha): 竹元 嘉利 岡山大学, 自然科学学域, 准教授 (60216942)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: マグネシウム合金 / ２Ｄセル状構造体 / 塑性変形 / 機械材料 / 力学的性質 / 変形双晶 / ひずみ勾配

Outline of Final Research Achievements

The present work was performed to quantitatively understand the mechanical behavior of magnesium alloys having poor ductility and rigidity, and establish a design method for 2D cellular structures to maximize the characteristics of desired functions. First, the fundamental knowledge about the hydrostatic stress dependence of plastic deformation and forming limits, and the effect of texture on mechanical properties of AZ31 magnesium alloy. Next, a new tensile bending testing method using rhombus-shaped specimens was developed to evaluate the optimal shapes of 2D unit cell structure. By utilizing this testing method and the finite element method analysis, the design guidelines for 2D cell shapes with superior deformability and rigidity were obtained. Furthermore, the possibility for the application of magnesium alloy 2D cells to auxetic structures was demonstrated.

Free Research Field

材料力学，弾塑性工学，応用固体力学

Academic Significance and Societal Importance of the Research Achievements

マグネシウム合金は軽量かつ高比強度で生体適合性に優れる一方，特定の方位関係で活動する変形双晶とも相まって延性や剛性に乏しい短所を有する．近年，その２Ｄセル状構造体には医療機器等への応用が期待されているが，所望機能を発現させるためのセル形状設計指針は未解明である．本研究では，２Ｄセル状構造体の定量評価を可能にする新たな試験法を提案し，有限要素法解析を援用して有用性を示した．また，その試験法を用いて力学的特性を向上させる設計指針を見出した．これらの成果は，マグネシウム合金製２Ｄセル状構造体の最適設計に寄与するとともに，社会的にはセル構造を活かした医療機器等の性能向上に貢献するものと期待される．