1、Designation: D3878 07 (Reapproved 2013)Standard Terminology forComposite Materials1This standard is issued under the fixed designation D3878; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in pa
2、rentheses indicates the year of last reapproval. Asuperscript 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. Scope1.1 These definitions cover generic terms, including termsof commercia
3、l importance, that appear in one or more stan-dards on composites containing high-modulus (greater than20-GPa (3 106psi) fibers.1.2 The definitions cover, in most cases, special meaningsused in the composites industry. No attempt has been made toinclude common meanings of the same terms as used outs
4、idethe composites industry.1.3 Definitions included have, in general, been approved asstandard.2. Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to Textiles2.2 Military Standard:MIL-HDBK-1733. Terminology3.1 Definitions:645 laminatea balanced symmetric laminate composed ofonly +45
5、 plies and 45 plies.angleply laminateany balanced laminate consisting of plusand minus theta plies where theta is an acute angle withrespect to a reference direction.balanced laminateany laminate that contains one ply ofminus theta orientation with respect to the laminate principalaxis for every ide
6、ntical ply with a plus theta orientation.braided fabricsee braided fabric under fabric.breather string, na string, composed of a material such asglass, that provides a vacuum path from the laminate to abreather.bundlea general term for a collection of essentially parallelfilaments.carbon fiber precu
7、rsora material from which carbon fiberis made by pyrolysis. Polyacrylonitrile, rayon, or pitch fibersare commonly used precursors.catenary:filament catenarythe difference in length of the filamentsin a specified length of tow, end, or strand as a result of unequaltension; the tendency of some filame
8、nts in a taut horizontaltow, end, or strand to sag lower than others.roving catenarythe difference in length of the ends, tows,or strands in a specified length of roving as a result of unequaltension; the tendency of some ends, tows, or strands in a tauthorizontal roving to sag lower than others.cau
9、l, na flat or contoured tool used to distribute pressure andto define a surface for the top of the laminate during laminateconsolidation or cure.co-fabrication, nin sandwich constructions, a fabricationprocess where items such as inserts and other structuraldetails are bonded into the panel at the s
10、ame time that thefacings are bonded to the posite:composite materiala substance consisting of two or morematerials, insoluble in one another, which are combined toform a useful engineering material possessing certain proper-ties not possessed by the constituents.DISCUSSIONa composite material is inh
11、erently inhomogeneous on amicroscopic scale but can often be assumed to be homogeneous on amacroscopic scale for certain engineering applications. The constitu-ents of a composite retain their identities: they do not dissolve orotherwise merge completely into each other, although they act inconcert.
12、discontinuous fiber-reinforced composite any compositematerial consisting of a matrix reinforced by discontinuousfibers. The fibers may be whiskers or chopped fibers.1This terminology is under the jurisdiction of ASTM Committee D30 onComposite Materials and is the direct responsibility of Subcommitt
13、ee D30.01 onEditorial and Resource Standards.Current edition approved May 1, 2013. Published May 2013. Originallyapproved in 1981. Last previous edition approved in 2007 as D3878 07. DOI:10.1520/D3878-07R13.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer
14、 Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from ASTM International as The Composite Materials HandbookMIL 17. Also available as MIL-HDBK-17 from Standardization Documents OrderDesk, DODS
15、SP, Bldg. 4, Section D, 700 Robbins Ave., Philadelphia, PA 19111-5094Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1fabric-reinforced compositeany composite material con-sisting of a matrix reinforced by fabric (woven, knitted, orbra
16、ided assemblages of fibers).fiber-reinforced compositeany composite material consist-ing of a matrix reinforced by continuous or discontinuousfibers.filamentary compositea composite material reinforcedwith continuous fibers.unidirectional fiber-reinforced composite any fiber-reinforced composite wit
17、h all fibers aligned in a single direc-tion.continuous filament yarn, ntwo or more continuous fila-ments twisted into a single fiber bundle.crossply laminatea laminate composed of only 0 and 90plies. This is not necessarily symmetric.dam, na solid material (such as silicone rubber, steel, oraluminum
18、), used in processing composites, to contain thematrix material within defined boundaries or to preventcrowning of a processing bag.damage, nin structures and structural mechanics, a struc-tural anomaly in material or structure created by manufac-turing or service usage.damage resistance, n in struc
19、tures and structuralmechanics, a measure of the relationship between the force,energy, or other parameter(s) associated with an event orsequence of events and the resulting damage size and type.DISCUSSIONDamage resistance increases as the force, energy, orother parameter increases for a given size o
20、r type of damage.Conversely, damage resistance increases as damage decreases, for agiven applied force, energy, or other parameter. Damage resistance anddamage tolerance are often confused. A material or structure with highdamage resistance will incur less physical damage from a given event.Material
21、s or structures with high damage tolerance may incur varyinglevels of physical damage but will have high amounts of remainingfunctionality.Adamage-resistant material or structure may, or may not,be considered damage tolerant.damage tolerance, n1) in structures and structure materials,a measure of th
22、e relationship between damage size and typeand the level of a performance parameter, such as stiffness orstrength, at which the structure or structural material canoperate for a particular loading condition; 2) in structuralsystems, a measure of the ability of such systems to functionat designated p
23、erformance parameters (for example,magnitude, length of time, and type of loading(s) withoutsystem failure in the presence of a particular or specifiedlevel of damage.DISCUSSIONDamage tolerance involves, and can be provided by, anumber of factors operating at a number of levels: structural material,
24、structural, and overall system. These factors include 1) basic materialability to operate with damage present (often referred to as the residualstrength aspect), 2) damage growth resistance and containment pro-vided by material and structural considerations, and 3) system inspec-tion and maintenance
25、 plans which allow the damage to be detected andcorrected and which depend upon material, structural, and operationalconsiderations.Damage tolerance increases as the damage size increases for a givenlevel of a performance parameter. Damage tolerance increases as thelevel of the performance parameter
26、 increases for a given damage size.Damage tolerance depends upon the type of loading which is applied.For example, the damage tolerance for a compressive load can be, andgenerally is, different than for the same level of tensile load.Damage resistance is often confused with damage tolerance. Dam-age
27、 tolerance is directly related only to the size and type of damagewhile being only indirectly related to how the damage was created (seedamage resistance). Thus, damage tolerance is distinct from damageresistance.debonda deliberate separation of a bonded joint or interface,usually for repair or rewo
28、rk purposes.debulk, vto decrease voids between lamina before laminateconsolidation through use of vacuum or by mechanicalmeans.DISCUSSIONLaminae can be debulked at ambient or elevatedtemperatures.delaminationseparation of plies in a laminate. This may belocal or may cover a large area in the laminat
29、e.denier, na direct numbering system for expressing lineardensity, equal to the mass in grams per 9000 metres of yarn,filament, fiber, or other textile strand.disbondan area within a bonded interface between twoadherents in which an adhesive or cohesive failure hasoccurred. It may occur at any time
30、during the life of thestructure and may arise from a wide variety of causes. It issometimes used to describe an area of separation betweentwo laminae in the finished laminate (the term “delamina-tion” is preferred).discontinuous fibera polycrystalline or amorphous fiberthat is discontinuous within t
31、he sample or component or thathas one or both ends inside of the stress field underconsideration. The minimum diameter of a discontinuousfiber is not limited, but the maximum diameter may notexceed 0.25 mm (0.010 in.).end, nin fibrous composites, a general term for a continuous,ordered assembly of e
32、ssentially parallel, collimatedfilaments, with or without twist.DISCUSSIONThis term covers tow, strand, sliver, yarn, and roving.The relationship between fiber form terms is shown in Table X1.1.fabrica planar textile (Synonym: cdth)braided fabric, na cloth constructed by a braiding process.knitted f
33、abric, na cloth constructed by a knitting process.nonwoven fabric, na cloth constructed by bonding orinterlocking, or both (but not interlacing) fiber by any combi-nation of mechanical, chemical, thermal, or solvent means.plied yarn, na yarn formed by twisting together two ormore single yarns in one
34、 operation.DISCUSSIONPlying, which is done in the opposite direction from thetwist of each of the simple yarns, serves to counter the tendency ofsimple yarns to untwist.woven fabric, na cloth constructed by a weaving process.fabrication, nthe process of manufacturing, forming,constructing, or assemb
35、ling a product or component.fiber, none or more filaments in an ordered assemblage.D3878 07 (2013)2DISCUSSIONThere are a number of general and specific terms thatdefine specific types of fiber forms. The relationship between fiber formterms is shown in Table 1.fiber contentthe amount of fiber presen
36、t in a compositeexpressed either as percent by weight or percent by volume.This is sometimes stated as a fraction, that is, fiber volumefraction.fiber volume fractionsee fiber content.filament, na fibrous form of matter with an aspect ratio 10and an effective diameter =3.Other material properties ma
37、yfollow different rules. For example, thermal conductivity becomesquasi-isotropic for k=2,while strength properties generally are notcapable of true quasi-isotropy, only approximating this behavior.reinforcement, nin a composite material, the discrete con-stituent of a composite material, either fib
38、er or particle,which is contained within the matrix, with a purpose ofincreasing the strength, or stiffness, or both.resina solid or pseudosolid organic material often of highmolecular weight, which exhibits a tendency to flow whensubjected to stress, usually has a softening or melting range,and usu
39、ally fractures conchoidally.resin contentsee matrix content.roving, nin fibrous composites, large filament count tow.(See also tow and filament count.)satin, adjdescription of a weave pattern in which warp yarnspass unbound (“float”) over several fill yarns before crossingunder a single fill yarn.DI
40、SCUSSIONA satin weave is characterized by parallel fibers and nodiagonal pattern.selvage, nthe woven edge portion of a fabric parallel to thewarp.single yarnSee single yarn under yarn.stacking sequencethe arrangement of ply orientations andmaterial components in a laminate specified with respect tos
41、ome reference direction.staple, na collection of discontinuous filaments of spinnablelength that are natural, manufactured directly in a shortlength, or cut from continuous filaments.strand in fibrous composites, Synonym for tow.symmetric laminatea laminate in which the stacking se-quence for the pl
42、ies located on one side of the geometricmidplane are the mirror image of the stacking sequence onthe other side of the midplane.tab, na piece of material used to hold the laminate specimenin a grip or fixture for testing so that the laminate is notdamaged and is adequately supported.textile, na gene
43、ral term applied to fibers and organizedassemblies of fibers with sufficient integrity to retain theorganization.DISCUSSIONOriginally limited to woven fabrics, this term is nowalso applied to fibers, yarn intermediates, yarns, woven and nonwovenfabrics, braids, knits, and preforms, as illustrated in
44、 Fig. 1.thermoplastica plastic that repeatedly can be softened byheating and hardened by cooling through a temperaturerange characteristic of the plastic, and that in the softenedstate can be shaped by flow into articles by molding orextrusion.D3878 07 (2013)4thermoseta class of polymers that, when
45、cured using heat,chemical, or other means, changes into a substantiallyinfusible and insoluble material.towin fibrous composites, a continuous, ordered assembly ofessentially parallel, collimated filaments, normally withouttwist and of continuous filaments (Synonyms: strand andsilver).twist, nin fib
46、rous composites, a measure of the number ofturns per unit length a fiber bundle makes around its axis.DISCUSSIONTwist is noted as being either S-twist or Z-twist,where the shape of the letters are used as a mnemonic to describe thedirection of the twist. Following the right-hand rule along the axis
47、ofthe fiber bundle, Z-twist is a positive twist and S-twist is a negativetwist. In addition, U is often used to represent no twist (untwisted) andN no twist (never twisted).voidany pocket of enclosed gas or air within a composite.void content, nthe volume percentage of voids in a compos-ite.warp, n(
48、1) the yarn running lengthwise in a woven fabric;(2) a group of yarns in long lengths and approximatelyparallel, put on beams or warp reels for further textileprocessing including weaving, knitting, twisting, dyeing,and so forth. D123warp nested, adjlaid up so that warp plies alternate in thepattern
49、: warp surface up, warp surface down.warp surface, nthe ply surface that shows the larger area ofwarp tows with respect to fill tows.DISCUSSIONFabrics in which both surfaces show an equal area ofwarp tows with respect to fill tows do not have a warp surface.weave, vinterlaces, in a specific pattern, strands or yarnsoriented in two or more directions in a planar textile process.windinga process in which continuous material is appliedunder controlled tension to a form in a prede
