대한기계학회논문집 (Transactions of the Korean Society of Mechanical Engineers)
- 제12권6호
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- Pages.1320-1326
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- 1988
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- 1225-5963(pISSN)
DOI QR Code
304스테인리스강의 고온표면미소 균열의 거동에 관한 기초적 연구
Behaviors of surface micro-crack of 304 stainless steel at elevated temperature
초록
본 연구에서는 파괴역학적인 해석법과 표면레프리카법을 확장, 적용시켜 피로 -크리프하의 유지시간에 따른 작은 표면균열의 분포상태와 이의 합체, 성장 및 밀도변 화특성을 해석하여 기초적 자료를 얻는다.
This paper deals with the behavior of surface crack growth and the characteristics of surface micro-crack distribution under creep and creep-fatigue with 1 min. and 10 min. of load holding times at 593.deg.C, in air. The test specimen is a plate type with a small artificial defect of type 304 the small defect has been carried out by the surface replica method and optical microphotography. The experimental results have been interpreted from the view-point of fracture mechanics. It can be concluded that the longer the hold time the longer the total life time. Most of surface micro-cracks initiate at grain boundaries before the specimen reaches 20% of its total life time, a few of them lead to fracture by coalescence with the main crack.
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