プラスティックに変形した多晶体における粒体内三次元張力テンソール場
Yujiro Hayashi1, Daigo Setoyama2, Yoshiharu Hirose2
1Toyota Central R&D Laboratories, Nagakute, Aichi 480-1192, Japan. y-hayashi@mosk.tytlabs.co.jp.
まとめ
鋼の内部緊張は,低変形でも平均値とマクロの強度を超えています. これらの局所的ストレスフィールドを理解することは,重要なアプリケーションにおける材料の故障を予測するために不可欠です.
科学分野:
- 材料科学
- 固体力学
- X線物理学
背景:
- インフラや輸送における多結晶材料の壊滅的な故障は,高度な予測モデルを必要とします.
- マルチスケールモデリングは,合金変形と故障を予測するために正確な内部ストレスフィールド測定を必要とします.
研究 の 目的:
- プラスチカルに変形した散発鋼の3次元内粒子の張力テンソール場を決定する.
- 穀物平均のストレスから局所的な粒体内ストレスの偏差を調査する.
主な方法:
- 高エネルギーX線マイクロビーム技術を使った
- 散らばった鋼の個々の粒の中で測られた三次元張力テンソールフィールド.
主要な成果:
- 粒体内の局所的ストレスと粒子の平均ストレスの間の有意な偏差が観察されました.
- 微細の張力が 微細の張力を超えたことを発見した
- 均一な伸長よりも低い変形でも粒子の内部で高度に三軸的ストレス状態を特定した.
結論:
- 微細粒子の内部のストレスフィールドは,マクロスコピーの性質と大きく異なっており,それを超えている.
- マルチスケールモデリングには,粒体内ストレスのテンサーフィールドの正確な測定が不可欠です.
- この能力は,材料の変形と故障の理解と予測を強化します.
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