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ASTM Selected Technical Papers
Composite Materials: Fatigue and Fracture, Fourth Volume
By
W Stinchcomb
W Stinchcomb
1
Virginia Polytechnic Institute and State University and the U.S. Air Force Academy
;
symposium chairman and editor
Search for other works by this author on:
N Ashbaugh
N Ashbaugh
2
University of Dayton, Research Institute
,
Dayton, OH
;
symposium chairman and editor
Search for other works by this author on:
ISBN-10:
0-8031-1498-2
ISBN:
978-0-8031-1498-2
No. of Pages:
6608
Publisher:
ASTM International
Publication date:
1993

Quasi-static tension tests were conducted on AS4/3501-6 graphite epoxy (022/-θ2)s laminates, where θ was 15, 20, 25, or 30°. Dye penetrant-enhanced X-radiography was used to document the onset of matrix cracking in the central - θ° plies and the onset of local delaminations in the θ/-θ interface at the intersection of the matrix cracks and the free edge. Edge micrographs taken after the onset of damage were used to verify the location of the matrix cracks and local delaminations through the laminate thickness.

A quasi-3D finite element analysis was conducted to calculate the stresses responsible for matrix cracking in the off-axis plies. Laminate plate theory indicated that the transverse normal stresses were compressive. However, the finite element analysis yielded tensile transverse normal stresses near the free edge. Matrix cracks formed in the off-axis plies near the free edge where in-plane transverse stresses were tensile and had their greatest magnitude. The influence of the matrix crack on interlaminar stresses is also discussed.

1.
Reifsnider
,
K. L.
and
Talug
,
A.
, “
Analysis of Fatigue Damage in Composite Laminates
,”
International Journal of Fatigue
 0142-1123, Vol.
3
, No.
1
,
01
1980
, pp. 3–11.
2.
Kress
,
G. R.
and
Stinchcomb
,
W. W.
, “
Fatigue Response of Notched Graphite Epoxy Laminates
,”
Recent Advances in Composites in the United States and Japan
, ASTM STP 864,
American Society for Testing and Materials
,
Philadelphia
,
1985
, pp. 173–196.
3.
Murri
,
G. B.
,
O'Brien
,
T. K.
, and
Salpekar
,
S. A.
, “
Tension Fatigue of Glass/Epoxy and Graphite/Epoxy Tapered Laminates
,”
Proceedings
, 46th AHS Annual Forum, Vol.
1
,
05
1990
, pp. 721–734 (also in NASA TM 102628,
04
1990
,
NASA
,
Washington, DC
).
4.
O'Brien
,
T. K.
,
Rigamonti
,
M.
, and
Zanotti
,
C.
, “
Tension Fatigue Analysis and Life Prediction for Composite Laminates
,”
International Journal of Fatigue
 0142-1123, Vol.
11
, No.
6
,
11
1989
, pp. 379–394.
5.
O'Brien
,
T. K.
and
Raju
,
I. S.
, “
Strain Energy Release Rate Analysis of Delamination Around an Open Hole in a Composite Laminate
,”
Proceedings
, 25th AIAA Structures, Dynamics, and Materials Conference,
Palm Springs
,
05
1984
, AIAA-84-0961,
AIAA
,
New York
, pp. 526–536.
6.
Jones
,
R. M.
,
Mechanics of Composite Materials
,
McGraw-Hill
,
Washington, DC
,
1975
.
7.
Raju
,
I. S.
, “
Q3DG—A Computer Program for Strain Energy Release Rates for Delamination Growth in Composite Laminates
,” NASA CR 178205,
NASA
, Washington, DC,
11
1986
.
8.
Soni
,
S. R.
and
Kim
,
R. Y.
, “
Delamination of Composite Laminates Stimulated by Interlaminar Shear
,”
Composite Materials: Testing and Design (Seventh Conference)
, ASTM STP 893,
American Society for Testing and Materials
,
Philadelphia
,
1986
, pp. 286–307.
9.
Lagace
,
P. A.
and
Brewer
,
J. C.
, “
Studies of Delamination Growth and Final Failure under Tensile Loading
,”
Proceedings
, ICCM VI,
London
, Vol.
5
,
Elsevier
,
London and New York
,
07
1987
, pp. 262–273.
10.
Brewer
,
J. C.
and
Lagace
,
P. A.
, “
Quadratic Stress Criterion for Initiation of Delamination
,”
Journal of Composite Materials
, Vol.
22
, No.
4
,
12
1988
, pp. 1141–1155.
11.
Salpekar
,
S. A.
and
O'Brien
,
T. K.
, “
Analysis of Matrix Cracking and Local Delamination in (0/θ/-θ)s Graphite Epoxy Laminates under Tension Load
,”
Proceedings
, ICCM VIII,
Honolulu
,
07
1991
,
SAMPE
,
Covina, CA
.
12.
Fish
,
J. C.
and
O'Brien
,
T. K.
, “
Three-Dimensional Finite Element Analysis of Delamination from Matrix Cracks in Glass-Epoxy Laminates
,”
Composite Materials: Testing and Design (10th Volume)
, ASTM STP 1120,
American Society for Testing and Materials
,
Philadelphia
,
1992
.
13.
Sun
,
C. T.
and
Kelly
,
S. R.
, “
Failure in Composite Angle Structures, Part I: Initial Failure
,”
Journal of Reinforced Plastics and Composites
, Vol.
7
,
05
1988
, pp. 220–232.
14.
Martin
,
R. H.
and
Jackson
,
W. C.
, “
Damage Prediction in Curved Composite Laminates
,”
Composite Materials: Fatigue and Fracture, Fourth Volume
, ASTM STP 1156,
American Society for Testing and Materials
,
Philadelphia
,
1993
.
15.
O'Brien
,
T. K.
,
Johnston
,
N. J.
,
Raju
,
I. S.
, and
Morris
,
D. H.
, “
Comparisons of Various Configurations of the Edge Delamination Test for Interlaminar Fracture Toughness
,”
Toughened Composites
, ASTM STP 937,
American Society for Testing and Materials
,
Philadelphia
,
1987
, pp. 199–221.
16.
O'Brien
,
T. K.
, “
Characterization of Delamination Onset and Growth in a Composite Laminate
,”
Damage in Composite Materials
, ASTM STP 775,
American Society for Testing and Materials
,
Philadelphia
,
1982
, pp. 140–167.
17.
O'Brien
,
T. K.
, “
Mixed-mode Strain Energy Release Rate Effects on Edge Delamination of Composites
,”
Effects of Defects in Composite Materials
, ASTM STP 836,
American Society for Testing and Materials
,
Philadelphia
,
1984
, pp. 125–142.
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