同型弾性硬さの理論的限界にある機械的超材料
J B Berger1,2, H N G Wadley3, R M McMeeking1,2,4,5
1Materials Department, University of California, Santa Barbara, California 93106-5050, USA.
Nature
|February 21, 2017
まとめ
研究者は理論的な弾性限界を達成する新しい材料の幾何学を特定しました. この低密度のメカニカルメタマテリアルは,優れた硬さ,エネルギー吸収,そして簡単な折り畳み方法によって製造可能な調整可能な音響特性を提供します.
科学分野:
- 材料科学
- 機械工学
- メタマテリアル
背景:
- 高性能なアプリケーションは,ストレス下での形状制御と低密度を持つ材料を必要とします.
- バイオインスピレーションを受けた構造は ハネコムや格子のようなもので 厳密さと重さの比率が優れています
- 3Dプリントの進歩により 複雑で低コストなメタマテリアルの製造が可能になりました
研究 の 目的:
- 同位体弾性および張力エネルギー貯蔵のための理論上の上限を達成する材料の幾何学を特定する (ハシン・シュトリクマン上限).
- 様々な材料の幾何学で負荷下でのストレスのエネルギーの分布を理解する.
- 機械的なメタマテリアルの高弾性性能に関連した形態学的特徴を発見する.
主な方法:
- ストレスのエネルギー分布を評価するために,有限要素モデルと分析方法を使用した.
- 最適な材料の幾何学を特定するためにヒューリスティック最適化スキームを使用しました.
- 既存のトランスネットワークとアニゾトロプ的蜂巣との性能の比較
主要な成果:
- 同位体弾性硬さのハシン・シュトリクマン上限を達成する新しい材料の幾何学を特定した.
- 効率的な負荷移転には 固い,よく分散したプレートネットワークが不可欠であると判断した.
- このデザインは以前のメタマテリアルの限界を 超えていることが示されました
結論:
- 新しいプレートベースのメタマテリアルの設計は理論的な弾性限界を達成します.
- この材料は,高いエネルギー吸収,調整可能な音響帯の隙間,および熱絶縁などの有利な性質を備えています.
- デザインはシンプルで,オリガミのようなシート折り畳みと接着技術を使用して製造できます.
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