|
Vol.57, No.11, 695 ~ 701, 2019
|
| Title |
| Studies on the Microstructure-Controlled Zn Interlayer for Improving the Adhesion Strength of the Zn/Zn-Mg Double Layer Coating |
| 이승환 Seung-hwan Lee , 김회근 Hoe-kun Kim , 송면규 Myeon-kyu Song , 김정완 Jung-wan Kim , 이상율 Sang-yul Lee |
|
|
|
| Abstract |
| In this study, the microstructure-controlled Zn interlayers were synthesized to improve the adhesion strength of Zn/Zn-Mg double layer coatings. The coating chamber temperature and working pressure were controlled based on the Structure Zone Model principles, to obtain a dense columnar microstructure in the Zn interlayer. By controlling the coating chamber temperature, however, porous nanowire structures resulted in an increasing chamber temperature over 100 °C, suggesting that it was not possible to obtain a columnar microstructure of the Zn interlayer. On the other hand, it was possible to synthesize a dense columnar structure in the Zn interlayer by controlling the working pressure. Furthermore, by decreasing the working pressure during deposition, the density of Zn interlayer increased from 79.1% to 93.6%. A lap shear test was performed to evaluate the adhesion strength, and the adhesion strength of Zn /Zn-Mg double layer coatings increased from 20.38 MPa to 24.48 MPa as the density of the Zn interlayer increased. These adhesion strength results were higher than those of the commercial galvanized steels, suggesting that an additional improvement in the adhesion strength would be possible by controlling the microstructure of the Zn interlayer in the Zn/Zn-Mg double layer coatings.
(Received August 27, 2019; Accepted September 25, 2019) |
|
|
| Key Words |
| Zn interlayer, structure zone model, columnar structure, adhesion, lap shear test |
|
|
 |
|
