화염용사 거리에 따른 입자의 거동 및 Ni_20Cr 코팅층 특성 연구

초록

The present study aims to examine the influence of flame spray distance on the thermal behavior of micro-metal particles and the morphological characteristics of Ni20Cr layers coated on the preheated SCM415 substrates by using the conventional flame spray system. Commercially available nickel-based Ni20Cr particles with a mean diameter of 45 μm were used. In addition, CFD simulations using a commercial code (FLUENT ver. 6.3.26) were conducted to estimate temperature and velocity distributions of the continuous and discrete phases before impact on the substrate. From FE-SEM images of coated layers on the substrates, it was observed that as the spray distance decreased, the metal particle morphology showed splash-like patterns and such a short stretch shape, resulting from higher particle momentums and the impact of partially melted particles. Moreover, it was found that the spray distance should be considered as one of important parameters in controlling the porosity and the adhesion strength.

키워드