Corrosion mechanism of CuAl-NiC abradable seal coating system-The influence of porosity, multiphase, and multilayer structure on the corrosion failure

In this study, the corrosion behavior of the CuAl-NiC abradable seal coating system in chloride solution was investigated to systematically research the effect of porosity, multiphase, and multilayer structure on the corrosion failure. Through the composition and structure analysis, the corrosion process of the system was predicted and then verified with mercury intrusion porosimetry, cross-section SEM/EDS analysis, and electrochemical measurements. The results demonstrated that the interphase selective corrosion caused the porosity of the top layer to decrease first and then increase during the corrosion development. The interlayer galvanic corrosion, determined by the pore connectivity, is crucial for corrosion failure. (c) 2021 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

The corrosion behavior of the CuAl-NiC abradable seal coating system in chloride solution was systematically investigated, with a focus on the effects of porosity, multiphase, and multilayer structure on corrosion failure. Interphase selective corrosion and interlayer galvanic corrosion were identified as crucial factors leading to the corrosion failure of the system.