1. Mechanical Testing of Composites and their Constituents
Tests done to determine intrinsic material properties such as modulus and strength for use in design and analysis (major emphasis here)
Tests done to determine quality or acceptability of specific components during manufacturing (minor emphasis here)

2. American Society for Testing and Materials (ASTM) Standards
Test standards for polymer matrix and metal matrix composites - ASTM Vol Space Simulation; Aerospace and Aircraft; Composite Materials
Test standards for ceramic matrix composites – ASTM Vol – Refractories; Activated Carbon; Advanced Ceramics

3. HI-NICALONTM Type S CERAMIC FIBER

4. Direct measurement of fiber longitudinal properties Ef1 and Sf1(+)
Different ways of mounting fiber specimens on backing strip. (From ASTM
Standard C R08. Copyright ASTM International. With permission.)

5. Different failure modes for resin-impregnated strand test specimens
Different failure modes for resin-impregnated strand test specimens. (From ASTM
Standard D (2008). Copyright ASTM International. Reprinted with permission.)

6. Indirect measurement of fiber transverse modulus Ef2P
P = load
Prediction
Experimental data Δ
Δ = deflection
Diametral compression of fiber for measurement of fiber transverse Young’s modulus. (From Kawabata, S In Vinson, J.R. ed., Proceedings of the 4th Japan–U.S. Conference on Composite Materials, pp. 253–262. CRC Press, Boca Raton, FL. With permission.)

7. Tensile measurement of neat resin properties Em and Sm1(+)
ASTM D Type I, II, III, IV and V neat resin tensile specimen geometries.
(From ASTM Standard D Copyright ASTM International. Reprinted
with permission).

8. Standard Laboratory Atmosphere:
ASTM Conditioning Plastics and Electrical Insulating Materials for Testing
Standard Laboratory Atmosphere:
Temperature of 23C (73.4F) and relative humidity of 50%

9. Specimen for measurement of neat resin compressive properties Em and Sm1(-)
Neat resin compressive test specimen. (From ASTM Standard D
Copyright ASTM International. Reprinted with permission.)

10. Neat resin compression specimen support jig
Support jig for D compressive test specimen. (From ASTM Standard
D695-02a. Copyright ASTM International. Reprinted with permission.)

11. Compression test fixture for neat resin specimen
Compression fixture with ball-and-socket joint to minimize bending.
(From ASTM Standard D Copyright ASTM International.
Reprinted with permission.)

12. Three-point bending specimen for flexural properties of neat resin or composite. (From ASTM Standard D Copyright ASTM International. Reprinted with permission.) M
Bending moment diagram

13. Constituent Volume Fraction Measurement
Removal of resin matrix from composite sample by either chemical digestion with acids or other chemicals (carbon fiber composites), or resin burn-off in a furnace (glass fiber composites) according to ASTM Standard D
Computer-aided image analysis of digital photomicrographs to determine fiber area fractions of polished composite specimens

14. Composite tensile specimen for measurement of longitudinal properties E1 and SL(+)
Specimen geometry for ASTM D3039/D3039M-08 standard tensile test.
(Dimensions from ASTM D3039/D3039M-08. Copyright ASTM
International. Reprinted with permission.)

15. Typical stress-strain curves from D3039 specimen
Longitudinal and transverse strain data at different stresses for [0]8 graphite/epoxy tensile
specimen. (From Carlsson, L.A. and Pipes, R.B Experimental Characterization of
Advanced Composite Materials. Prentice-Hall, Inc., Englewood Cliffs, NJ. Reprinted by
permission of Prentice-Hall, Englewood Cliffs, NJ.)

16. End constraints can cause bending of off-axis tensile specimens due to shear coupling
Effect of end conditions on deformation of an off-axis tensile specimen
exhibiting shear coupling. (From Pagano, N.J. and Halpin, J.C 1968.
Journal of Composite Materials, 2, 18–31. With permission.)

17. Importance of specimen length-to-width ratio

18. Variation of “apparent moduli” and with fiber orientation for off-axis tensile test of a
unidirectional T300/934 carbon/epoxy lamina. Lamina engineering constants are
taken from Table 2.2. Conclusion: except at

19. Lamina tensile strength can be “backed out” from laminate tensile test data
“Backed out” tensile strength data from seven different laminates of IM7G/8551-7
graphite/epoxy. (From Rawlinson, R.A Proceedings of the 36th International
SAMPE Symposium and Exhibition, Book 1, pp. 1058–1068. Reprinted by permission
of the Society for the Advancement of Material and Process Engineering.)

20. Compression test specimen for
ASTM D3410/D3410M-03
D3410 fixtures produce
side-loading rather than
end-loading as in D695
Geometry for tabbed compression test specimen. (From ASTM Standard
D3410/D3410M-03 (Reapproved 2008). Copyright ASTM International.
Reprinted with permission.)

21. Cutaway view of compression test fixture for ASTM D3410/D3410M-03
Cross-section view of ASTM D3410/D3410M-03 (Reapproved 2008)
compression test fixture. (From ASTM Standard D3410/D3410M-03
(Reapproved 2008). Copyright ASTM International. Reprinted with permission.)

22. Sandwich beam specimen for face sheet compression
ASTM D5467/D5467M-97 (Reapproved 2004) sandwich beam specimen
for face sheet compression. (From ASTM Standard D5467/D5467M-97
(Reapproved 2004). Copyright ASTM International. Reprinted with permission.)

23. Test fixture for ASTM D 6641/D 6641M- 09
combined loading compression (CLC) test method
Test fixture for ASTM D6641/D6641M-09 CLC test method. (From ASTM
Standard D6641/D6641M-09. Copyright ASTM International. Reprinted
with permission.)

24. Test fixture for compressive residual strength of polymer
composite plates. (From ASTM D 7137/D 7137M-07)
Test fixture for compressive residual strength of polymer composite plates.
(From ASTM D7137/D7137M-07. Copyright ASTM International.
Reprinted with permission.)

25. Comparison of shear test methods for composites.
(From Adams, D.F., 2005 High Performance Composites, 13(5), pp. 9–10)

26. Iosipescu test fixture for shear strength
and stiffness in all three shear stress states
(ASTM D5379)

27. Test fixture for V-notched rail shear test
Test fixture for V-notched rail shear test. (From ASTM Standard
D7078/D7078M-05. Copyright ASTM International. Reprinted with permission.)

28. Different test specimen arrangements for
V-notched rail shear test. (From ASTM
Standard D7078/D7078M-05. Copyright
ASTM International. Reprinted with
permission.)

29. Rail shear test fixtures, ASTM D4255/D4255M-01
(Methods A and B)
Rail shear test fixtures. (From ASTM Standard D4255/D4255M-01(2007).
Copyright ASTM. Reprinted with permission.)

30. Analysis of Rail Shear Test Procedure A
Shear stress along loading axes x,y)
(10.8)
Strain transformation from normal strain along strain
gage axis x’ oriented at 45o from x to shear strain along
(x,y) axes
(10.10)

31. Therefore the shear modulus along loading axes is
where P, L, t, and εx’ are all measured quantities.
If the specimen is unidirectional, and (x,y) are aligned
with (1,2), then and if this specimen is
loaded to failure

32. Laminate test for in-plane shear modulus G12
Shear stress from applied stress:
Shear strain from measured normal strains:
Shear modulus:

33. Off-axis tensile test for indirect measurement of G12
Young’s modulus, Ex 2
When y
(2.39) or 1 x
(2.40)

34. Off-axis tensile test for indirect measurement of G12
Conduct off-axis tensile test to measure Ex at some fiber orientation θ
Conduct longitudinal tension test to measure E1 and υ12
Conduct transverse tension test to measure E2
Use above results in Eq to calculate G12

37. ASTM D2344/D2344M-00 Short beam shear test
for interlaminar strength (parallel fibers only)
Note: not recommended for measurement of intrinsic
properties, only for quality control and specification

38. Short beam test specimen with shear and moment diagrams
Mechanics of
materials stresses
Shear stress
Bending stress

39. Short beam shear test
Short beam fails due to interlaminar shear stress
Long beam fails due to either tensile or compressive normal stress on bottom or top of beam, respectively
Questions about accuracy of mechanics of materials beam theory equations for stresses in short beams where support effects may not be negligible (Whitney’s theory of elasticity analysis)

40. Whitney’s conclusion: Stress distributions from mechanics of materials beam theory are only accurate far away from loads and supports
Comparison of predicted interlaminar shear stress distributions from theory of
elasticity (solid curves) and beam theory (dotted curve) for a 50 ply short beam shear
specimen with length-to-depth ratio of 4. Differences are particularly large near
loading point (section C) and support points (section A). (From Whitney, J. M
Composites Science and Technology, 22, With permission)

41. Interlaminar Fracture Tests

42. DCB analysis – treat one half of DCB as cantilever beam
(ASTM D (2007)e3)
Mode I strain energy release rate
(10.16)

43. Mixed mode bending (MMB) test for Mode I
and Mode II delamination testing
(ASTM Standard D6671)
Test fixture for MMB test. (From ASTM Standard D6671/D6671M-06.
Copyright ASTM International. Reprinted with permission.)

44. Single fiber fragmentation specimen for measurement of fiber/matrix interfacial
shear strength
Test procedure: Load specimen until fiber starts to break up into
fragments, then measure “critical lengths” of fragments, then
calculate interfacial shear strength from theory of discontinuous
fiber composites developed in Chap. 6
Single-fiber fragmentation specimen developed by Drzal et al. (From Drzal, L.T.,
Rich, M.J., and Lloyd, P.F Journal of Adhesion, 16, 1–30.; Drzal, L.T., Rich, M.J.,
Koenig, M.F., and Lloyd, P.F Journal of Adhesion 16, 133–152. With permission.)

45. Microindenter test for fiber/matrix interfacial shear strength
Test procedure: Load end of fiber in compression with microindenter probe until fiber slips with respect to matrix, then use finite element analysis of specimen to estimatefiber/matrix interfacial shear strength
Microindenter test for fiber/matrix interfacial strength. (From Mandell, J.F., Grande, D.H.,
Tsiang, T.H., and McGarry, F.J Composite Materials: Testing and Design (Seventh
Conference), ASTM STP 893, pp. 87–108. American Society for Testing and Materials,
Philadelphia, PA. Copyright ASTM. Reprinted with permission.)

46. Microbond test for fiber/matrix interfacial shear strength
fiber embedded in
resin droplet
resin droplet
applied tensile force
Problem: Difficult to reproduce the composite
resin matrix cure condition in a small droplet.

47. Source: From McDonough, W. G. , Herrera-Franco, P. J. , Wu, W. L
Source: From McDonough, W.G., Herrera-Franco, P.J., Wu, W.L., Drzal, L.T., and
Hunston, D.L In Advanced Materials/Affordable Processes, Proceedings of
23rd International SAMPE Technical Conference, Kiamesha Lake, NY, pp. 247–258.
Society for Advancement of Material and Process Engineering, Covina, CA. Reprinted
by permission of the Society for the Advancement of Material and Process Engineering.

48. ASTM D5766 open hole tension test – similar to
ASTM D3039 tensile test, but with central hole
Acceptable test failure modes for ASTM D 5766/D 5766M-07 standard test method
for open hole tensile strength (a) failure mode codes (b) LGM (c) AGM (d) MGM.
(From ASTM D5766/D5766M Copyright ASTM International. Reprinted
with permission.)

49. ASTM D5961 bearing test – Procedure A
Fixture assembly for ASTM D5961/D5961M-08 (Procedure A) double shear test
method for bearing response of polymer matrix composite laminates. (From
ASTM D5961/D5961M Copyright ASTM International. Reprinted
with permission.)

50. ASTM D7332 fastener pull-through test
Test fixture and specimen for ASTM standard test method for measuring the fastener
pull-through resistance of a fiber-reinforced polymer matrix composite, Procedure B.
(From ASTM D 7332/D 7332M-07e1. Copyright ASTM International. Reprinted
with permission.)

51. Measurement of Viscoelastic and
Dynamic Properties

52. Creep test parameters Elastic compliance = εo/ σo
Total strain = εo+ε(t)
Strain, ε
Strain
gage
Creep strain, ε(t)
Initial elastic strain, εo
Test
specimen
Time, t
Elastic compliance = εo/ σo
Creep compliance = ε(t)/σo
Constant applied stress, σo

53. Measurement of orthotropic creep compliances

56. Empirical power law for creep compliance
where S(t) is the creep compliance, S0 the initial elastic
compliance, and S1 and n the empirically determined parameters

57. Important modes of specimen deformation
for vibration tests
Flexural
Torsional
Longitudinal

58. Natural frequencies of flexural and torsional modes of vibration are usually in the range of typical excitation frequencies, but longitudinal modes are usually well above this range. Automated Dynamic Mechanical Analyzers (DMA) typically operate in the flexural mode.
Range of typical
excitation frequencies
Longitudinal
modes
Response
Flexural and
torsional modes
Frequency

59. Representation of automated DMA plot showing storage
modulus, loss modulus and loss factor (tan δ) vs. temperature.

60. Material Damping
Energy dissipation within a material under cyclic or oscillatory stress
Characterized by stress-strain hysteresis loop under steady-state vibration and decaying oscillation under free vibration
Area enclosed by hysteresis loop and rate of decay are proportional to damping factor
Damping is linear if it is independent of oscillation amplitude
Hysteresis loop in
steady state vibration
Free vibration decay

61. Complex modulus of linear viscoelastic material from stress-strain hysteresis loop ( assuming perfectly elliptical loop)
Energy dissipated per cycle
Energy stored at maximum
displacement
Loss factor
Storage Modulus

62. Free vibration decay method
Logarithmic decrement
Loss factor (for light damping)

63. Impulse-frequency response method
Impulse-frequency response apparatus for
flexural vibration of cantilever beam specimens

64. Modal frequencies
Modal frequencies and loss factors found by curve-fitting to frequency response curve at peak frequencies

65. Single Degree of Freedom Curve Fit to Peak in Frequency Response Curve by Half Power Bandwidth Method
Peak for
nth mode
Amplitude X
0.707 X
Frequency ••
(10.36)
Damping Loss Factor
= natural frequency of nth mode
= bandwidth at half power points

66. Measurement of Hygrothermal Properties

67. Measurement of glass transition temperature, Tg
ASTM D e1 test for determination of DMA Tg
from storage modulus vs. temperature plot

68. ASTM 696-08 test for measurement of
coefficient of thermal expansion, CTE
Measure thermal strain, , or the change in length, ,
of a specimen of original length which is subjected
to a temperature change in an environmental chamber
Measured coefficient of thermal expansion is
(10.37)

69. Variation of measured longitudinal and transverse thermal strains for unidirectional Kevlar 49/epoxy and S-glass/epoxy with temperature. (From Adams, D.F., Carlsson, L.A., and Pipes, R.B., Experimental Characterization of Advanced Composite Materials. CRC Press, Boca Raton, FL. With permission.)

70. Measured CTEs for undirectional orthotropic lamina
Measured longitudinal CTE
Measured transverse CTE

71. ASTM D5229 test for measurement of moisture absorption properties
Through-thickness Diffusivity
(10.40)

72. Example of test done to determine quality or acceptability
of specific components during manufacturing
ASTM D2290 Split Disk Test for tensile strength
of filamentwound composite rings

73. Exploded view of test fixture for ASTM D2290 Split Disk Test for Rings