| Title |
Research Paper / Surfacr Treatment : Study on Properties of NiCrAlY/NiCrAlY+8wt%Y2O3-ZrO2/8wt%Y2O3-ZrO2 , Three - Layer Thermal Barrier Coatings ( TBCs ) Fabricated by Plasma Spray Method |
| Authors |
이선호(Seon Ho Lee); 유재성(Jae Sung You); 강춘식(Choon Sik Kang) |
| Abstract |
Thermal barrier coatings(TBCs) fabricated by plasma spray process is generally used for gas turbine and diesel engine to improve their efficiency and service life. In this study, intermediate mixed layer between bond and ceramic layer was sprayed to improve thermal shock lifetime through increase of adhesion strength. On spraying the mixed Layer, each melted droplet of bond and ceramic powder was not mixing. Thus, interface shape between bond and ceramic Layer showed the complicated morphology. The adhesion strength and the thermal shock lifetime were improved by maximum 1.2 and 1.5 times. respectively. It was judged that improvement of thermal shock lifetime was due to increase of adhesion strength and tensile residual stress. From the stress analysis of thermal shock procedure. it was proved that enlargement of fractured region was occurred because horizontal crack in the vicinity of interface propagated in the direction of surface. |