ASTM D3878-07
(Terminology)Standard Terminology for Composite Materials
Standard Terminology for Composite Materials
SCOPE
1.1 These definitions cover generic terms, including terms of commercial importance, that appear in one or more standards on composites containing high-modulus (greater than 20-GPa (3 10 6 psi)) fibers.
1.2 The definitions cover, in most cases, special meanings used in the composites industry. No attempt has been made to include common meanings of the same terms as used outside the composites industry.
1.3 Definitions included have, in general, been approved as standard.
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: D3878 − 07
StandardTerminology for
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Composite Materials
This standard is issued under the fixed designation D3878; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope braided fabric—see braided fabric under fabric.
1.1 These definitions cover generic terms, including terms
breather string, n—a string, composed of a material such as
of commercial importance, that appear in one or more stan-
glass, that provides a vacuum path from the laminate to a
dards on composites containing high-modulus (greater than
breather.
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20-GPa (3×10 psi)) fibers.
bundle—a general term for a collection of essentially parallel
1.2 The definitions cover, in most cases, special meanings
filaments.
used in the composites industry. No attempt has been made to
include common meanings of the same terms as used outside
carbon fiber precursor—a material from which carbon fiber
the composites industry. ismadebypyrolysis.Polyacrylonitrile,rayon,orpitchfibers
are commonly used precursors.
1.3 Definitions included have, in general, been approved as
standard.
catenary:
filament catenary—the difference in length of the filaments
2. Referenced Documents
inaspecifiedlengthoftow,end,orstrandasaresultofunequal
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2.1 ASTM Standards:
tension; the tendency of some filaments in a taut horizontal
D123Terminology Relating to Textiles
tow, end, or strand to sag lower than others.
2.2 Military Standard:
roving catenary—the difference in length of the ends, tows,
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MIL-HDBK-17
or strands in a specified length of roving as a result of unequal
tension; the tendency of some ends, tows, or strands in a taut
3. Terminology
horizontal roving to sag lower than others.
3.1 Definitions:
645° laminate—a balanced symmetric laminate composed of caul, n—aflatorcontouredtoolusedtodistributepressureand
todefineasurfaceforthetopofthelaminateduringlaminate
only +45° plies and −45° plies.
consolidation or cure.
angleply laminate—any balanced laminate consisting of plus
and minus theta plies where theta is an acute angle with co-fabrication, n—in sandwich constructions, a fabrication
respect to a reference direction. process where items such as inserts and other structural
details are bonded into the panel at the same time that the
balanced laminate—any laminate that contains one ply of
facings are bonded to the core.
minusthetaorientationwithrespecttothelaminateprincipal
axis for every identical ply with a plus theta orientation. composite:
composite material—a substance consisting of two or more
materials, insoluble in one another, which are combined to
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This terminology is under the jurisdiction of ASTM Committee D30 on
form a useful engineering material possessing certain proper-
Composite Materials and is the direct responsibility of Subcommittee D30.01 on
Editorial and Resource Standards.
ties not possessed by the constituents.
Current edition approved May 1, 2007. Published June 2007. Originally
DISCUSSION—a composite material is inherently inhomogeneous on a
approved in 1981. Last previous edition approved in 2004 as D3878–04a. DOI:
microscopic scale but can often be assumed to be homogeneous on a
10.1520/D3878-07.
macroscopic scale for certain engineering applications. The constitu-
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For referenced ASTM standards, visit the ASTM website, www.astm.org, or
ents of a composite retain their identities: they do not dissolve or
contactASTM Customer Service at service@astm.org. ForAnnual Book ofASTM
otherwise merge completely into each other, although they act in
Standards volume information, refer to the standard’s Document Summary page on
concert.
the ASTM website.
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Available from ASTM International as The Composite Materials Handbook—
discontinuous fiber-reinforced composite— any composite
MIL 17. Also available as MIL-HDBK-17 from Standardization Documents Order
material consisting of a matrix reinforced by discontinuous
Desk, DODSSP, Bldg. 4, Section D, 700 Robbins Ave., Philadelphia, PA 19111-
5094 fibers. The fibers may be whiskers or chopped fibers.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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D3878 − 07
level of the performance parameter increases for a given damage size.
fabric-reinforced composite—any composite material con-
Damage tolerance depends upon the type of loading which is applied.
sisting of a matrix reinforced by fabric (woven, knitted, or
For example, the damage tolerance for a compressive load can be, and
braided assemblages of fiber
...
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