在非静止的外部影响下进行热量和质量转移
Alexander Pogorelov1, Igor N Karnaukhov2
1G.V. Kurdyumov Institute for Metal Physics, 36 Vernadsky Boulevard, Kyiv, 03142, Ukraine.
Scientific reports
|September 26, 2025
概括
高能激光脉冲导致金属中的质量和热量转移加速. 位移有助于传热,与实验数据和Frenkel-Kontorova方程保持一致.
科学领域:
- 材料科学 材料科学 材料科学
- 物理 物理学 物理
- 热力学是一种热力学.
背景情况:
- 脉冲热暴露,特别是来自巨大的激光脉冲,显著影响材料性能.
- 在极端条件下了解质量和热传递动力学对于材料加工至关重要.
- 在描述高脉冲功率的动力过程时,菲克定律的局限性要求调查.
研究的目的:
- 在高能脉冲激光激发下研究金属中的质量和热传递现象.
- 分析受脉冲热暴露的金属的结构变化.
- 探索在高速变形过程中能量转移中脱位的作用.
主要方法:
- 在脉冲功率条件下对质量和热传递的实验研究.
- 分析Q开关激光脉冲引起的结构变化.
- 应用Frenkel-Kontorova (FK) 方程用于排位能量转移估计.
- 使用激光闪光方法进行热物理研究.
- 计算皮尔尔斯应力.
主要成果:
- 在小型和大型脉冲功率条件下,研究了晶格的高能激发.
- 在高速金属变形下,加速的质量和热传递过程具有共同的性质.
- 位移有助于传热,能量估计与实验激光闪光方法结果保持一致.
- 菲克定律对于描述异常大脉冲功率的动力过程是不够的.
结论:
- 定向脱位流量对热传输有很大的贡献,由Frenkel-Kontorova方程和实验数据验证.
- 该研究提供了极端脉冲热负荷下质量和热传递机制的见解.
- 计算的皮尔斯应力提供了进一步了解这些条件下的材料行为.
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