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金属中的微粒子冲击诱导的键强度与速度的峰值
Qi Tang1, Yuji Ichikawa2, Mostafa Hassani1,3
1Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14853.
概括
微粒的超音速冲击粘合显示其峰值强度在1060m/s左右. 较高的速度降低了由于强化的弹性回收和界面损伤而导致的粘合强度,而不是化.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 表面科学是一门学科.
背景情况:
- 微粒的超音速冲击使得固态金属结合成为可能.
- 较高的冲击速度通常被认为是为了提高粘合质量.
研究的目的:
- 研究撞击速度对单微粒子撞击的界面强度的影响.
- 确定实现最大结合强度的最佳速度.
主要方法:
- 在Al基板上对 (Al) 微粒的界面强度的现场微机械测量.
- 分析不同冲击速度的结合机制.
主要成果:
- 界面强度增加到1,060 m/s,显示了从800 m/s的临界结合速度的三倍增长.
- 超过1060m/s,界面强度下降,即使在速度低于化或侵蚀值.
- 从材料强化到强化弹性恢复的机制性过渡被确定为强度峰值和随后下降的原因.
结论:
- 超音速冲击粘合时的峰值粘合强度在最高速度下无法实现.
- 强化弹性回收和与之相关的在高速速度下增强性软化会导致界面损伤,降低整体结合强度.
- 了解这种机制对于优化冲击结合过程至关重要.
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