Flattening mechanism in thermal sprayed nickel particle impinging on flat substrate surface

被引：98
作者：
Fukumoto M. [1 ]
Huang Y. [1 ]
机构：
[1] Dept. of Prod. Systems Engineering, Toyohashi University of Technology, Aichi, 441-8580, 1-1, Tempaku-cho, Toyohashi
来源：
Journal of Thermal Spray Technology | 1999年 / ASM International, Materials Park, OH, United States卷 / 08期
关键词：
This research was supported by the Grant-in-Aid for Scientific Research of The Ministry of Education; Science; Culture; and Sports in Japan;
D O I：
10.1361/105996399770350386
中图分类号：
学科分类号：
摘要：
The transition behavior of the splat pattern of nickel particles sprayed onto a flat substrate was investigated. Auger analysis and scanning electron microscopy observation of splats on a gold- coated substrate were examined. It was confirmed that splashing was not formed by flowing on the substrate surface from the impingement center to the periphery, but by jetting away from central disk. The etched splat surface revealed that the bottom part of the central disk of the splat solidified quite rapidly just after impingement onto the cold substrate. The splash pattern was found only in a direction perpendicular to the scratch pattern on the substrate. Therefore, it was confirmed that splashing was caused by some deterrent to the liquid flow, for example, due to effects such as poor wettability at the flow tip or initial rapid solidification of the splat. The drastic change of the splat pattern near the transition temperature seems to occur when the We number of the liquid flow coincides with some critical value.
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页码：427 / 432
页数：5
相关论文
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