复合涂层激光熔池凝固过程的数值模拟

基金项目:

湖北省自然科学基金;博士点基金;华中科技大学校基金资助

详细信息

A numerical simulation for solidification process of laser pool for composite coating system

1.
Department of Physics, Capital Normal University, Beijing, 100037;
2.
Department of Physics and Materials Science, City University of Hong Kong, Hong Kong;
3.
Tsinghua Univ ersity, Beijing, 100084
4.
School of Materials Science and Engineering, HUST, Wuhan, 430074

摘要: 采用数值模拟技术研究了复合涂层激光熔池凝固过程。结果表明其凝固过程分为凝固准稳态阶段和凝固加速阶段两个阶段。在凝固准稳态阶段,熔池熔深和半径变化较小,但表面最高温度、熔池流速急剧减小;凝固加速阶段则反之。凝固准稳态阶段,由于上熔池的高度过热,下熔池产生后熔现象,形成后熔区。影响后熔的主要因素是熔覆层和过渡区凝固过程中释放的潜热和熔覆层的过热。
- 激光熔池 /
- 复合涂层 /
- 凝固过程 /
- 后熔区
Abstract: In this paper, solidification process of laser pool for composite coating system is studied, using numerical technology. The results demonstrate that solidification process may be divided into two stages: quasi-state stage and accelerating stage. At quasi-state stage, the depth and radius of laser pool have small changes, but the highest surface temperature and velocity of molten pool decease rapidly. At the accelerating stage, those are on the contrary. Because of highly overheating in upper molten pool, post molten phenomenon is produced in down molten pool, during solidification quasi-state stage. The key factors to produce post molten region are the overheating and the latent heat released during solidification process in upper molten pool.
- laser pool /
- composite coating /
- solidification process /
- post molten region

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