在巩固和分离过程中,纳米粉Ti的冲击诱导的塑性变形
Debing He1, Mingyang Wang1, Wenbo Bi2
1College of Science, Hunan Agricultural University Changsha Hunan 410128 People's Republic of China wangliang0329@hunau.edu.cn.
RSC advances
|March 14, 2024
概括
纳米粉末 (np-Ti) 的冲击负荷通过孔隙崩和塑性变形产生大量的纳米结构. 较高的速度诱导分离和微喷射,揭示了纳米晶体材料中复杂的冲击诱导机制.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 计算材料科学科学 计算材料科学
背景情况:
- 通过冲击载荷巩固纳米粉末金属是合成批量纳米晶体材料的关键方法.
- 在纳米粉末巩固过程中,微观结构特征和塑性变形机制尚不清楚.
研究的目的:
- 为了研究在冲击过程中纳米粉末 (np-Ti) 中的塑料变形,密集,散积和微喷射.
- 阐明控制这些现象在纳米尺度的潜在机制.
主要方法:
- 利用分子动力学 (MD) 模拟来模拟np-Ti在冲击负载下的行为.
- 分析了微观结构的演变,包括可塑性,密度和缺陷形成.
主要成果:
- 观察到从异质可塑性 (堆叠断层,结合) 过渡到同质失调随着撞击速度的增加.
- 纳米粉结构通过缩过程中的孔隙崩转化为散装纳米结构.
- 裂变和微喷射发生在撞击速度≥1.0公里s-1时,由谷物边界滑动,扰乱和纳米孔效应驱动.
结论:
- 对np-Ti的冲击影响会诱导复杂的塑料变形和密集,导致散装纳米结构.
- 在释放期间的解部分恢复了结构,而在更高的冲击速度下,分离和微喷射是显著的.
- 模拟MD提供了关键的洞察力,纳米粉的冲击巩固的机制.
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