|
2971 |
|
Tuesday, September 27, 2011, Saal B2.2 11:50 AM Modeling & Simulation 1 |
|
Splat formation mechanism in thermal spray process according to substrate temperature and ambient pressure change |
|
Masahiro Fukumoto* / Toyohashi University of Technology, Japan Kun Yang/ Toyohashi University of Technology, Japan Yoshinori Ebisuno/ Toyohashi University of Technology, Japan Shogo Yoshida/ Toyohashi University of Technology, Japan Motohiro Yamada/ Toyohashi University of Technology, Japan Toshiaki Yasui/ Toyohashi University of Technology, Japan |
|
In order to understand the flattening behavior of individual splat deposited by thermal spraying, commercially available metal powders were thermally sprayed onto AISI304 substrate surface. The deposited splat shows transition phenomenon from splash type to disk one in flattening on collision onto substrate surface according to both substrate temperature and ambient pressure change. That is, transition temperature, Tt and transition pressure, Pt can be defined as critical values for the transitions. The three-dimensional map was set up to control the thermal spraying process. The observation on the bottom surface morphology on single splat indicates that the initial solidification may dominate the splat formation process. Moreover, the thermal history of the free falling Cu droplet onto AISI304 substrate was investigated, indicating the flattening pattern is decided just after collision onto solid surface, which is enough earlier to finalization of the flattening. |