| 학회 |
한국재료학회 |
| 학술대회 |
2017년 봄 (05/17 ~ 05/19, 목포 현대호텔) |
| 권호 |
23권 1호 |
| 발표분야 |
D. 구조 재료 분과 |
| 제목 |
A Mechanism of Corrosion Fatigue Cracking for Ni-base Alloy X-750 |
| 초록 |
Hydrogen embrittlement is known as the intergranular crack growth mechanism of alloy X-750. In order to study the corrosion fatigue cracking mechanisms, the microstructure was analyzed after two different heat treatments, with the first using the AH condition consisting of a stress-equalizing anneal (885 °C) for 24 hours and aging (704 °C) for 20 hours and the second using the HTH condition consisting of solution anneal (1093 °C) for 1hour and aging (704 °C) for 20 hours. The microstructure of the AH heat treated specimens showed that the γ′ phase precipitates with discontinuous intergranular carbides, which are known to accelerate intergranular cracking, were generally formed at the vicinity of the grain boundary, while continuous intergranular carbides were found at the surface of the HTH heat treated specimens. Corrosion fatigue tests were performed in several environments to show the hydrogen effect on intergranular cracking. Single-edge notched specimens made of AH heat treated alloy X-750 were tested under cyclic loading in different environments including pure water and Na2SO4 solution, as well as air under the same mechanical conditions. The cathodic potential was applied to change the dissolved hydrogen concentration at the crack tip through cathodic polarization of X-750. All equipment and procedures were prepared and conducted in accordance with the ASTM method E647-08. |
| 저자 |
이태현1, 윤재영2, 류경하1, 이상혁1, 김영중1
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| 소속 |
1한국기계(연), 2한국원자력(연) |
| 키워드 |
Ni based alloy X 750; Corrosion fatigue; Heat treatment; Microstructure; Hydrogen embrittlement
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| E-Mail |
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