| Title |
A Study on the Surface Modification of Ni - Base Self - Fluxing Alloy Coating by HVOF Process |
| Authors |
한동운(Dong Woon Han); 김한삼(Han Sam Kim); 김수식(Soo Sik Kim) |
| Abstract |
The Ni-base self fluxing alloy was coated on SM45C using High Velocity Oxygen Fuel(H.V.O.F) spray process. The effects of post-treatments such as fusing treatment and aluminizing on the wear and corrosion resistance of the coating were studied. Borides such as Ni₄B₃ and Cr_5B₃ were formed by fusing treatment at 1050℃ for 10∼30min. The borides contributed to the increase in hardness and wear resistance. A dense diffusion layer was formed by aluminizing on the coating at 900℃. As a result of the cyclic hot corrosion test, it came to have the best corrosion resistance when it was performed at 900℃ for 3hrs in the pack composition of 75%Al₂O₃: 20%Al : 5%NH_6Cl. Although the unstable Ni₂Al₃ phase formed in the coating surface was changed to stable NiAl by means of homogeneous treatment, the corrosion resistance was not changed significantly. |