Proceedings of the Korean Society of Precision Engineering Conference (한국정밀공학회:학술대회논문집)
- 2003.06a
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- Pages.729-732
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- 2003
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- 2005-8446(pISSN)
Determination of CTOD & CTOA Curve for Structural Steel Hot-Rolled Thin Plates
일반 구조용강 열간압연 박판에 대한 CTOD와 CTOA 곡선 결정
Abstract
The K-R design curve is an engineering method of linear-elastic fracture analysis under plane-stress loading conditions. By the way, linear-elastic fracture mechanics (LEFM) is valid only as long as nonlinear material deformation is confined to a small region surrounding the crack tip. Like general steels, it is virtually impossible to characterize the fracture behavior with LEFM, in many materials. Critical values of J contour integral or crack tip opening displacement (CTOD) give nearly size independent measures of fracture toughness, even for relatively large amounts of crack tip plasticity. Furthermore, the crack tip opening displacement is the only parameter that can be directly measured in the fracture test. On the other. the crack tip opening angle (CTOA) test is similar to CTOD experimentally. Moreover, the test is easier to measure the fracture toughness than other method. The shape of the CTOA curve depends on material fracture behavior and, on the opening configuration of the cracked structure. CTOA parameter describes crack tip conditions in elastic-plastic materials, and it can be used as a fracture criterion effectively. In this paper, CTOA test is performed for steel JS-SS400 hot-rolled thin plates under plane-stress loading conditions. Special experimental apparatuses are used to prevent specimens from buckling and to measure crack tip opening angle for thin compact tension (CT) specimens.
Keywords
- Crack Tip Opening Displacement(CTOD);
- Crack Tip Opening Angle(CTOA);
- J-integral;
- Elastic-Plastic Fracture Toughness;
- Ductile Fracture;
- Plane Stress;
- Compact Tension specimen(CT)
- 균열 선단 열림변위;
- 균열 선단 열림각;
- J 적분;
- 탄.소성 파괴인성치;
- 연성파괴;
- 평면응력;
- 소형인장시편;