Papers by Author: Choul Jun Choi

Abstract: Applied gas turbine blade material(Ni base Super-alloy) for aircraft as principal parts material of existing electricity generating gas turbine blade. Studied microstructure change after do heat treatment, Hot Isostatic Press(HIP) processing to nickel-based super-alloy. Emphasize in properties of matter refreshing effect confirmation by HIP processing, microstructure observed by scanning electron microscope. HIP processing effect caused positive effect in high temperature Creep and low cycle fatigue failure by microscopic air hole exclusion. Sheep of Eutectic region decreased solid solution being done B, and also precipitated size of cuboidal shape great. Heat treatment effect was seen modification by M23C6 carbide creation that Script MC carbide is microscopic and does Discrete through solution treatment in high temperature state. Precipitation that grow after HIP processing over solution processing and aging processing in heat treatment process solid solution after is done again precipitate being done size decrescent.

Abstract: Combustion gas of gas turbine is about 1100 ~ 1300 °C. Is doing TBC(Thermal Barrier Coating) on the base metal surface to protect rotor or blade from high temperature flame. TBC system reduced heat transfer as metal base metal. TBC system is divided by bond coating of prevent oxidation and corrosion and Top coating reduced of heat transfer by high Temperature flame. The objective of this study was to development of an advance TBC system for high Temperature (>1350°C) gas turbine components. Used coating powder developed newly in coating process, and more than 1350°C by parameter control in usable coating method develop. Internal studies looked at the effect of TBC coating thickness, material chemistry, substrate composition, surface temperature and bond coat as-sprayed surface profile/particle size on technical performance.