関連する実験動画
Updated: Jul 10, 2026
09:41
Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides
Published on: May 29, 2018
オスミウムジボリドは,超圧縮不可能な硬質物質である
Robert W Cumberland1, Michelle B Weinberger, John J Gilman
1Department of Chemistry and Biochemistry, University of California, Los Angeles, 90095-1569, USA.
Journal of the American Chemical Society
|May 19, 2005
まとめ
研究者はOsB2を,高い電子密度と結合共電性に焦点を当てて,超硬質物質として特定した. この材料は特殊な硬さと圧縮不能性を発揮し,ダイヤモンドに匹敵する.
科学分野:
- マテリアルサイエンス 材料科学
- 固体物理 固体物理学
- クリスタログラフィーです.
背景:
- 耐磨性・耐掻き材料の開発は,先進技術アプリケーションにとって極めて重要です.
- 超硬質材料は,高要求の工業プロセスに不可欠であり,新しい化合物の研究を推進しています.
- 高硬度および非圧縮性などの優れた機械的特性を持つ材料を特定することは,依然として重要な科学的課題です.
研究 の 目的:
- 特定の設計パラメータを使用して,超非圧縮性および超硬質の材料を特定します.
- オスミウム二酸化物 (OsB2) を潜在的な超硬質材料候補として調査する.
- OsB2.2のボリュームモジュールと硬さを実験的に決定する.
主な方法:
- 高価率電子密度と高結合共価性に重点を置いた設計原理の適用.
- 位高圧X線微分法で,OsB2.2の質量モジュールを測定した.
- 素材の硬さを評価するために,サファイア窓に対するスクラッチテストを行います.
主要な成果:
- オスミウム二酸化物 (OsB2) は超硬質物質として特定されました.
- OsB2の測定されたバルクモジュールは365~395GPaで,圧縮不能性が高いことを示しています.
- OsB2は2000kg/mm2を超える硬さを示し,サファイアの硬さを上回りました.
結論:
- オスミウム二酸化物 (OsB2) は,超非圧縮性および超硬質の材料の性質を示しています.
- 材料のアニゾトロプ的構造は,そのユニークな機械的特性に寄与する.
- OsB2は,さまざまな用途で既存の超硬質材料に有望な代替品を提示しています.
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