NiAl-X (X=Zr, Hf)합금의 NiAl-X/산화피막계면에 대한 미세조직과 산화피막의 박리성에 관한 평가

Evaluation of the Microstructure and Peelability of the Oxide Film on the NiAl-X/oxide Film Interface of NiAl-X (X=Zr, Hf) Alloy

본 연구에서는 β-NiAl-0.1 at%X (X=Zr, Hf)합금에 대하여 NiAl 및 Zr, Hf를 첨가한 합금의 산화피막 형상에 대한 거시적 관찰, NiAl/산화피막 및 NiAl-Zr/산화피막 계면에 대한 미세조직 관찰을 진행하여 산화피막의 박리성에 관한 평가를 실시하였다. 단시간의 산화는 거시적으로는 균일한 두께의 피막이 형성되어 있지만, 그물망 형상에 산화물이 형성되어, 국부적으로 산화의 진행이 지연되는 부분이 관찰되었다. 산화시간이 길어짐에 따라서 그물망 형상의 산화물은 굵기가 굵어져 점점 치밀한 산화피막으로 변화하고 있는 것이 관찰되었다.

In this study, macroscopic observation of the oxide film morphology of alloys containing NiAl, Zr and Hf for β-NiAl-0.1 at.%X (X=Zr,Hf) alloy, and the microstructure of the NiAl/oxide film and the NiAl-Zr/oxide film interface was observed to evaluate the peelability of the oxide film. The oxidation in a short time was macroscopically formed with a film having a uniform thickness, but an oxide was formed in a mesh shape, and a part where the progress of oxidation was locally delayed was observed. As the oxidation time became longer, it was observed that the oxide of the mesh form became thicker and gradually changed into a dense oxide film.