Ni-Cr계 내열주강의 천이액상접합에 관한 연구

Abstract

본 연구에서는 MBF-50 삽입금속을 이용한 Ni-Cr주강(HP)의 천이액상접합시의 접합계면의 거동에 대해서 조사하였다. 접합은 진공분위기에서 1100℃∼1200℃의 온도 범위로 0∼60분 동안 행해졌으며 접합압력은 1MPa였다. 본 실험에서 얻어진 결과는 다음과 같다. 1) 1150℃에서 접합한 결과 반응층 내에는 Cr계 탄화물의 생성을 확인할 수 있었다. 2) 유지시간의 증가와 함께 등온응고는 매우 빠르게 일어나 20분 이내에 반응층이 거의 소멸되었으며 성분원소의 균일화도 거의 이루어진 상태였다. 3) 등온응고가 일어나기 이전의 접합부의 경도는 모재에 비해 높게 나타났으나, 유지시간이 증가하면서 균일화와 함께 반응층의 경도는 모재와 같게 나타났다. 4) 접합계면부의 각도를 달리하여 접합한 시편의 creep 특성을 조사한 결과 접합계면각도가 작을수록 creep 특성이 우수하게 나타났다.

Transient liquid phase(TLP) bonding of Ni-Cr heat resisted casting alloy(HP) was investigated using of the insert metal MBF-50. TLP-bonding was carried out at 1100℃∼1200℃ for 0∼60min in vacuum atmosphere and bonding pressure was 1MPa. The results of this study are, 1) Microconstituents such as Cr-carbide were formed in the bonded interlayer. 2) Isothermal solidification process was very fast at the bonding temperature of 1150℃ with increasing bonding time, the reaction layer disappeared and homogenization was almost over at the bonding time of 20min. 3) The hardness of reaction layer was higher than that of base metal before isothermal solidification, as time increased the hardness was almost same as that of base metal with homogenization of chemical composition. 4) In case of sample with different bonding interface angle, the smaller bonding interface angle, the better creep property.

Transient liquid phase(TLP) bonding of Ni-Cr heat resisted casting alloy(HP) was investigated using of the insert metal MBF-50. TLP-bonding was carried out at 1100℃∼1200℃ for 0∼60min in vacuum atmosphere and bonding pressure was 1MPa. The results of this study are, 1) Microconstituents such as Cr-carbide were formed in the bonded interlayer. 2) Isothermal solidification process was very fast at the bonding temperature of 1150℃ with increasing bonding time, the reaction layer disappeared and homogenization was almost over at the bonding time of 20min. 3) The hardness of reaction layer was higher than that of base metal before isothermal solidification, as time increased the hardness was almost same as that of base metal with homogenization of chemical composition. 4) In case of sample with different bonding interface angle, the smaller bonding interface angle, the better creep property.