2020 Fiscal Year Final Research Report

Advances in particle deposition process based on verification of dynamic wetting

Research Project

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Project/Area Number	18H01748
Research Category	Grant-in-Aid for Scientific Research (B)
Allocation Type	Single-year Grants
Section	一般
Review Section	Basic Section 26050:Material processing and microstructure control-related
Research Institution	Toyohashi University of Technology
Principal Investigator	Fukumoto Masahiro 豊橋技術科学大学, 研究推進アドミニストレーションセンター, 特任教授 (80173368)
Project Period (FY)	2018-04-01 – 2021-03-31
Keywords	溶射 / 溶射粒子 / プロセス制御 / 粒子偏平 / 動的ぬれ / 遷移温度 / 解離圧
Outline of Final Research Achievements	On the thermal spraying, deposition mechanism of an individual particle has not been clarified. Verification on the deposition mechanism has been desired from the viewpoint of process controllability. Since the melted and accelerated particle with um size is the fundamental element for the coating formation, contact and flattening behavior of the particle on the substrate can be defined as dynamic wetting, in which heat and mass transfer simultaneously at splat/substrate interface. Verification on dynamic wetting is the main issue of this study. From the result of XPS analysis both on the particle and the substrate surface, it was found that the relative relationship on the dissociation pressure between metal oxide of the sprayed particle and iron oxide on the SUS304 substrate dominates dynamic wetting at splat/substrate interface. Furthermore, this relative relationship decides transition temperature for each metallic material, thermally sprayed onto the substrate surface.
Free Research Field	材料工学，材料加工学
Academic Significance and Societal Importance of the Research Achievements	熱的に平衡で物質の移動を伴わない静的ぬれに対し，熱・物質の同時移動を伴う動的ぬれは未知の学術領域である．本研究は国内外に先駆けて，単一溶射粒子の基材表面への接触偏平物理の解明に着手したものであり，基材温度，雰囲気圧力の変化において粒子偏平形態が遷移的急峻に変化する臨界値：遷移温度，遷移圧力を国内外に先駆けて見出した．また各粒子材質の遷移値が周期表に一致する等の諸点を明らかにし，特に本研究で得た酸化物解離圧の相対関係が動的ぬれを支配するとの知見は高い学術性を与えている．一方，遷移温度の概念は国内溶射製品製造ラインの制御指針に導入される社会実装を果たしており，社会貢献性は計り知れない．