|
Vol.42, No.6, 471 ~ 479, 2004
|
| Title |
| Microstructures and Phase Compositions of the NiCr-Cr2O3-Ag-BaF2/CaF2 Coatings Using the Atmospheric Plasma Spraying |
| 한창민 Chang Min Han , 최한신 Han Shin Choi , 김길영 Gil Young Kim , 이창희 Chang Hee Lee , 황순영 Soon Young Hwang |
|
|
|
| Abstract |
| A blended NiCr-Cr₂O₃-Ag-CaF₂/BaF₂ feedstock was sprayed using an atmospheric plasma spraying. Physical and thermophysical properties of each constituent phase are quiet different and resulting interactions of each constituent with the plasma jet can be expected to be different. Thus, an attempt to change the plasma jet characteristics by changing the hydrogen gas flow rate in view of the thermophysical properties of the plasma jet was tried. According to the hydrogen gas flow rate, phase compositions and microstructures were evaluated. The effects of phase composition and microstructure on the Vickers microhardness and bond strength were also evaluated. For empirically tracing the each constituent particle trajectory, spot spraying bead was produced. Finally, particle temperature and velocity according to the hydrogen gas flow rate was measured using alumina-titania particle instead of the blended feedstock. (Received January 19, 2004) |
|
|
| Key Words |
| Atmospheric plasma spraying, NiCr-Cr2O3-Ag-BaF2/CaF2 blended feedstock, Coating microstructure |
|
|
 |
|
