Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (30권4호 285-297)

A Study on the high temperature oxidation behavior of zirconia plasma coatings on Haselloy X

Zirconala 용사된 Hastelloy X의 고온산화거동

김재철;신억균;박영규;최시경;김길무;

전력연구원 재료부식연구소;충남대학교 재료공학과;한국과학기술원 재료공학과;

Abstract

Finned segment, with which are lined inner wall of the turbine combustors, are subject to severe degradation when they are exposed to a hostile environmment at elevated temperature. To protect the finned segment from this environment and to maintain good mechanical properties of components at high temperature, they are preferred to be coated. The most governing factor for the durability of coatings used in the high temperature is the microstructure of coatings; these are splat from, distibution of microcacks, size and distribution of pores, thickness of coating layer, adhesion between coating layer, and oxidation of band coating. In this study, based on the evaluation of the imported finned segment, new finned segment segment was manufactured with optimum plasma spraying parameters, and their properties were examined. Using $ZrO_2(8wt$Y_2O_3)$,/TEX> powder for ceramic coating and 67Ni-22Cr-10Al-0.5Y mixing powder for bond coating, thickness of ceramic and bond coating layer were varied in order to find optimum condition, the results showed that B2T4(bond coating : 100~250$mu extrm{m}$, ceramic coating : 250~300$mu extrm{m}$) was the best among the specimens tested. Compared to the imported finned segment, B2T4 has better bond strength, hardness, and isothermal and cyclic oxidation resistance.

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