http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Crack Band Model을 이용한 탄소섬유강화 복합재료 적층판의 점진적 파손거동에 관한 연구
윤동현(Donghyun Yoon),김상덕(Sangedeok Kim),김재훈(Jaehoon Kim) 대한기계학회 2019 대한기계학회 춘추학술대회 Vol.2019 No.5
In this paper, a progressive failure analysis was developed using the Hashin failure criterion and crack band model. Using the failure criterion, the failure initiation was evaluated. If the failure initiation is occurred, the damage variables at each failure modes (fiber tension & compression, matrix tension & compression, matrix tension & compression) was calculated according to linear softening degradation behavior and the variables are used to derive the damaged stiffness matrix. The damaged stiffness matrix is reflected to degraded material and the progressive failure analysis is continued until the damage variables to be 1 that compete failure of material. A series of processes were performed using FE commercial code ABAQUS with user defined material subroutine (UMAT). To evaluate the proposed progressive failure model, the experimental results of open hole composite laminate tests was compared with numerical result. Using digital image correlation system, the strain behavior also was compared. The proposed numerical results were coincided well with the experimental results.
LSI 공법으로 제작된 C/SiC 복합재의 압축거동 평가
윤동현(Donghyun Yoon),이정원(Jeongwon Lee),김재훈(Jaehoon Kim),김연철(Yunchul Kim),신인철(Ihncheol Sihn),임병주(ByungJoo Lim) 한국추진공학회 2016 한국추진공학회 학술대회논문집 Vol.2016 No.12
액상 실리콘 함침법(Liquid silicon infiltration, LSI) 공정을 통해 제작된 탄소섬유 강화 실리콘 카바이드 (C/SiC) 복합재의 압축강도에 대한 섬유 방향, 시편 크기, 그리고 온도의 영향을 연구하였다. 섬유 방향에 대한 변수로 시험 하중 방향에 대해 수직으로 섬유방향을 가진 Across grain(A/G) 시편과 평행으로 섬유방향을 가지는 With grain(W/G) 시편을 제작하였다. 크기효과를 보기 위해 직경대 높이 비가 1:2, 1:1의 비를 가지는 시편을 각각 제작하여 시험하였다. 온도는 상온, 500℃, 그리고 900℃로 설정하였고 산화의 영향을 배제하기 위해 산화방지제를 도포하였다. 압축강도는 온도 증가에 따라 높게 나타났으며, 크기 변화에 따른 압축강도 영향은 Grain에 따라 다른 양상을 보였다. The effects of the fiber direction, specimen size and temperature on the compressive strength of carbon fiber reinforced silicon carbide composite (C/SiC composite) manufactured by liquid silicon infiltration(LSI) is investigated. Tests were conducted in accordance with ASTM C 695 at room temperature and elevated temperatures. Experiments are conducted with two different specimens considering grain direction. With grain (W/G) specimens have a carbon fibers parallel to the load direction, but across grain (A/G) specimens have a perpendicular carbon fibers. To verify the specimen size effect of C/SiC composite, two types of specimens are manufactured. One has a one to two ratio of diameter to height and the other has a one to one ratio. The compressive strength of C/SiC composite increased as temperature rise. As specimens are larger, compressive strength of A/G specimens increased, however compressive strength of W/G decreased.