对撞击诱导的能量释放和核心外结构的Ni/Al纳米粒子在氧气环境中的变形的原子洞察力
Kexin Zhu1, Yifan Xie1, Jian-Li Shao1,2
1State Key Laboratory of Explosion Science and Safety Protection, Beijing Institute of Technology, Beijing 100081, China.
Materials (Basel, Switzerland)
|August 29, 2024
概括
在氧气中对Ni/Al纳米粒子的高速冲击会引起复杂的反应. 模拟显示变形,融化和碎片化,影响氧化和金属间反应释放的能量.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学计算化学
- 材料机械学 材料机械学
背景情况:
- / (Ni/Al) 复合材料在高速冲击下表现出复杂的能量释放,原因是同时发生的金属间反应和氧化性燃烧.
- 了解机械变形和化学过程之间的相互作用对于预测反应性环境中的材料行为至关重要.
研究的目的:
- 通过使用ReaxFF分子动力学模拟,在氧气环境中研究核心外Ni/Al纳米颗粒的冲击诱导变形和能量释放.
- 阐明撞击速度和材料结构对Ni/Al纳米粒子碎片化,化和化学反应的影响.
主要方法:
- 使用ReaxFF分子动力学模拟来建模Ni/Al纳米粒子在高速冲击下的行为.
- 在氧气环境中进行模拟,以捕捉氧化燃烧效应.
- 分析的重点是变形机制,碎片化模式和能量释放途径.
主要成果:
- (Al) 碎片,而 (Ni) 经历了连续的塑性变形,化和碎片化,冲击速度增加.
- 纳米粒子形态从圆形结构过渡到球形融化和碎片云.
- 观察到Ni-Al-O集群解离,由Ni解离和Al氧化驱动.
- 能量释放与变形有关:在部分破碎时,氧化和金属间反应占主导地位,而在完全碎片化时,碎片云燃烧占主导地位.
- 增加氧气度可以提高能量释放效率.
结论:
- /纳米粒子的变形和能量释放特性高度依赖于撞击速度和外材料特性.
- 模拟提供了对反应性金属间纳米颗粒中能量释放的合机械和化学过程的原子层次见解.
- 这些发现为规范这些材料中冲击诱导的能量释放提供了基础.
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