• 제목/요약/키워드: Delamination Shape Factor (f$_{}$ s/)

검색결과 5건 처리시간 0.017초

층간분리 요소와 층간분리 성장의 관계 (The Relationship Between Delamination Element and Delamination Growth)

  • 송삼홍;김철웅;홍정화;김태수;황진우
    • 한국복합재료학회:학술대회논문집
    • /
    • 한국복합재료학회 2003년도 춘계학술발표대회 논문집
    • /
    • pp.113-116
    • /
    • 2003
  • The investigation of delamination growth behavior in hybrid composite material such as FRMLs should be considered delamination growth rate, dA_D/da$ using the delamination shape factor, $f_S$ instead of traditional fracture mechanics parameters. The main objective of this study is to evaluate the relationship between delamination element (i. e. delamination width, b, delamination contour, c, delamination shape factor, $f_S$ and delamination growth rate, dA_D/da$) and delamination growth in FRMLs under cyclic bending moment. The delamination shape formed along the fatigue crack between aluminum layer and glass fiber/epoxy layer are measured by scanning method. The details of study are as follow : ⅰ) Relationship between crack length, a and delamination width, b. ⅱ) Variation of delamination growth rate, dA_D/da$ was attendant on delamination shape factors, $f_{S1}$, $f_{S2}$, $f_{S3}$. The test result indicated the delamination growth behavior depends in delamination element such as delamination width, b, delamination shape factors, $f_{S1}$, $f_{S2}$, $f_{S3}$.

  • PDF

층간분리 형상계수($F_s$)가 FRMLs의 층간분리 성장률($dA_D/da$)에 미치는 영향 (The Effect of Delamination Shape Factor, $f_s$ on the Delamination Growth Rate, $dA_D/da$ in FRMLs)

  • 송삼홍;이원평;김광래;김철웅
    • 한국공작기계학회:학술대회논문집
    • /
    • 한국공작기계학회 2003년도 춘계학술대회 논문집
    • /
    • pp.398-404
    • /
    • 2003
  • Most previous researches for the hybrid composite materials such as FRMLs(Al/AFRP, Al/GFRP) have evaluated the fatigue delamination behavior using the traditional fracture mechanism. However, most previous researches have not generally been firmed yet. Because delamination growth behavior in hybrid composite should be consider delamination growth rate, $dA_D$/da using the delamination shape factors, fs instead of traditional fracture mechanic parameters. The major purpose of this study was to evaluate the relationship between delamination shape factor, fs and delamination growth rate, $dA_D$ . And a propose parameter on the delamination aspect ratio, b/a. The details of the study are as follow : 1) Relationship between crack length, a and delamination width,b. 2) Relationship between delamination aspect ration, b/a and delamination area rate,($(A_D)_{N}(A_D)_{ALL}$. 3) Variation of delamination growth rate, $dA_D/da$ was attendant on delamination shape factors, $fs_1$, $fs_2$, $fs_3$. The test results indicated the delamination growth rate depends on delamination shape factors.

  • PDF

Development of the Delamination Evaluation Parameters (I) -The Delamination Aspect Ratio and the Delamination Shape Factors-

  • Song, Sam-Hong;Oh, Dong-Joon
    • Journal of Mechanical Science and Technology
    • /
    • 제18권11호
    • /
    • pp.1932-1940
    • /
    • 2004
  • Although the previous researches evaluated the fatigue behavior of Al/GFRP laminates using the traditional fracture mechanism, their researches were not sufficient to do it : the damage zone of Al/GFRP laminates was occurred at the delamination zone instead of the crack-metallic damages. Thus, previous researches were not applicable to the fatigue behavior of Al/GFRP laminates. The major purpose of this study was to evaluate delamination behavior using the relationship between crack length (a) and delamination width (b) in Al/GFRP laminate. The details of investigation were as follows: 1) Relationship between the crack length (a) and the delamination width (b), 2) Relationship between the delamination aspect ratio (b/a) and the delamination area rate ((A$\_$D/)/subN// (A$\_$D/)$\_$All/), 3) The effect of delamination aspect ratio (b/a) on the delamination shape factor (f$\_$s/) and the delamination growth rate (dA$\_$D// da). As results, it was known that the delamination aspect ratio (b/a) was decreased and the delamination area rate ((A$\_$D/)$\_$N// (A$\_$D/)$\_$All/) was increased as the normalized crack size (a/W) was increased. And, the delamination shape factors (f$\_$s/) of the ellipse-II(f$\_$s3/) was greater than of the ellipse-I(f$\_$s2/) but that of the triangle (f$\_$s1/) was less than of the ellipse-I(f$\_$s2/).

층간분리성장률(dAD/da)과 섬유가교효과인자(FBE)를 이용한 Al/GFRP 적층재의 피로거동 해석 (The Analysis of Fatigue Behavior Using the Delamination Growth Rate(dAD/da) and Fiber Bridging Effect Factor(FBE) in Al/GERP Laminates)

  • 송삼홍;김철웅
    • 대한기계학회논문집A
    • /
    • 제27권2호
    • /
    • pp.317-326
    • /
    • 2003
  • The influence of cyclic bending moment on the delamination and the fatigue crack propagation behavior in Al/GFRP laminate such as the wing section was investigated. The main objective of this study was to evaluate the relationship between crack profile and delamination behavior. And a propose parameter on the delamination growth rate(d $A_{D}$/da) of Al/GFRP laminates with a saw-cut using relationship between delamination area( $A_{D}$) and cycles(N), crack length(a), stress intensity factor range($\Delta$K). Also, the fiber bridging effect factor( $F_{BE}$ ) was propose that the fiber bridging modification factor($\beta$$_{fb}$ ) to evaluate using the delamination growth rate(d $A_{D}$/da). The shape and size of the delamination zone formed along the fatigue crack between aluminum alloy sheet. Class fiber-adhesive layer were measured by an ultrasonic C-scan image. The shape of delamination zone turns out to be semi-elliptic with the contour decreased non-linearly toward the crack tip. It represents that relationship between crack length and delamination growth rate(d $A_{D}$/da) were interdependent by reciprocal action, therefore it's applicable present a model for the delamination growth rate(dA/sib D//da) in Al/GFRP laminates.minates.s.

균열길이와 층간분리 폭의 관계를 이용한 하이브리드 복합재의 층간분리 거동 평가 (Evaluation of Delamination Behavior in Hybrid Composite Using the Crack Length and the Delamination Width)

  • 송삼홍;김철웅
    • 대한기계학회논문집A
    • /
    • 제28권1호
    • /
    • pp.55-62
    • /
    • 2004
  • Although the previous researches evaluated the fatigue behavior of glass fiber/epoxy laminates using the traditional fracture mechanism, their researches were not sufficient to do it: the damage zone of glass fiber/epoxy laminates was occurred at the delamination zone instead of the crack-metallic damages. Thus, previous researches were not applicable to the fatigue behavior of glass fiber/epoxy laminates. The major purpose of this study was to evaluate delamination behavior using the relationship between crack length and delamination width in hybrid composite material such as Al/GFRP laminate. The details of investigation were as follows : 1) Relationship between crack length and delamination width, 2) Relationship between delamination aspect ratio and delamination area rate, 3) Variation of delamination growth rate is attendant on delamination shape factors. The test results indicated that the delamination growth rate depends on delamination width delamination aspect ratio and delamination shape factors.