Experimental and Numerical Modeling for Flattening and Rapid Solidification with Crystallization Behavior of Supersonic Ceramic Droplets
| Autor: | Yiwen Sun, Xiaojuan Du, Zhaobin She, Wu Kai, Yu Bai, Qi Liu, Yongbao Hu, Zhou Jun, Nanjing Chong, Yu Wang, You Ming, Mingguang Shen |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Coalescence (physics)
Equiaxed crystals Materials science multiphase flow Multiphase flow Surfaces and Interfaces Mechanics Flattening Surfaces Coatings and Films law.invention Physics::Fluid Dynamics Temperature gradient Grain growth lcsh:TA1-2040 law Materials Chemistry Supersonic speed supersonic droplets refinement grain growth Crystallization lcsh:Engineering (General). Civil engineering (General) numerical model |
| Zdroj: | Coatings Volume 10 Issue 11 Coatings, Vol 10, Iss 1047, p 1047 (2020) |
| ISSN: | 2079-6412 |
| DOI: | 10.3390/coatings10111047 |
| Popis: | Successive impingement of droplets after refining in supersonic plasma jet generally yields a submicron-sized lamellar coating with excellent comprehensive properties. Nevertheless, physical insight into the flattening and rapid solidification with crystallization behavior of supersonic impingement of refined droplets is difficult to understand. In this research, the content of refinement droplets reached 90% and displayed the multi-scale distribution of equiaxed grains. The boundary migration of equiaxed grains and anisotropic coalescence was found in the dynamic temperature gradient. Furthermore, an optimized model was established in order to accurately reproduce the multi-physical coupling process of supersonic impingement of single or two refined droplets, which was based on the numerical calculation of nonlinear equations (including the Mass and momentum, energy balance, Cahn&ndash Hilliard, phase-field and orientational field equations). The size distribution and growth orientation of columnar grains within single or two flattened droplets were in good agreement with the experimental results. Epitaxial growth of columnar grains was found in the two-flattened droplet interface during the extremely rapid cooling stage. This optimized model could be an effective method in predicting the flattening and solidification with crystallization behavior of droplets during plasma spraying. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|