니켈기 초내열합금 Alloy 263의 고온인장 및 크리프 변형기구

• Published in: 대한금속·재료학회지, 49(7) Vol. 49; no. 7; pp. 535 - 540
• Main Authors: 김인수, In Soo Kim, 최백규, Baig Gyu Choi, 홍현욱, Hyun Uk Hong, 조창용, Chang Yong Jo
• Format: Journal Article
• Language: Korean
• Published: 대한금속재료학회 20.07.2011; 대한금속·재료학회
• Subjects: creep; deformation twin; Ni-base superalloy; tensile; 재료공학
• ISSN: 1738-8228; 2288-8241

The tensile and creep behaviors of Alloy 263, which is a wrought Ni-base superalloy used for gas turbine combustion systems, was studied. Anomalous increase of yield strength and abrupt decrease of elongation with increasing temperature were observed after tensile testing at an intermediate temperature. Elongation of the superalloy decreased as the temperature increased to and above 540℃, and it reached a minimum value at 760℃. It was found that creep strain was also very low at the same temperature. Inhomogeneous deformation with intensive slip bands was observed in the specimens tested at low temperature. A thermally-assisted dislocation climb process was regularly conducted at high temperature. Twinning was found to be an important mechanism of both tensile and creep deformations of the superalloy at an intermediate temperature where ductility minimum was observed.