ASTM_D_3918_-_11.pdf

Designation:D391811Standard Terminology Relating toReinforced Plastic Pultruded Products1This standard is issued under the fixed designation D3918;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 parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 These definitions cover terms used in the reinforcedplastics pultrusion industry.In some cases the terms may beidentical to those employed in other standards.NOTE1There is no known ISO equivalent to this standard.2.Terminologybarcol hardnessa measurement of the surface hardnessusing a Barber Colman impresser.NOTE2The Barcol hardness is a relative measure of cure and thenominal value can differ on a fully cured part with the use of differentadditives.blistera rounded elevation of the pultruded surface withboundaries that may be more or less sharply defined.Ablister may be a small percentage or large percentage of thepultruded part surface.NOTE3The rounded elevation somewhat resembles a blister on thesurface of human skin.Blisters may exist within the pultrusion as a hollowarea(usually gas-filled)under a raised portion of the surface.blooming,fibera pultrusion surface condition exhibiting afiber prominence or fiber show that usually has a white orbleached color on parts without a surfacing veil.NOTE4The surface generally feels rough when touched by the fingersand is of superficial thickness easily removed by buffing or light sanding.There is not a structural issue.blooming,undercurea dull and bleached surface color thatis evident in pultruded material not exposed to the weather.NOTE5This condition is usually the result of insufficient surface cure.bowSee camber and straightness.camberthe deviation of the edge or surface of a pultrudedshape from a reference straight line.chipsminor damage to the pultruded surface that removesmaterial but does not cause a crack or craze.Typicallycaused by minor impact damage closed shape-a pultrudedshape that has a hollow component.cracka visual separation that occurs internally or penetratesdown from the pultruded surface to the equivalent of one fullply or more of reinforcement(at least 0.019 in.or 0.48 mm).cratera small,shallow pultrusion surface imperfection.crazemultiple fine cracks at or under the pultruded surface.craze,hairlinemultiple fine pultrusion surface separationcracks that exceed14in.(6.4 mm)in length and do notpenetrate in depth to the equivalent of full ply of reinforce-ment.craze,resinmultiple fine separation cracks at the pultrudedsurface not penetrating into the reinforcement.NOTE6This condition is usually due to resin shrinkage during cure inresin-rich areas.delaminationthe separation of two or more layers or plies ofreinforcing material within a pultrusion,which increases thelocalized part thickness by more than 0.13 mm(0.005 in.).die-parting linea lengthwise flash or depression on thesurface of a pultruded plastic part.NOTE7The die-parting line is associated with the area where separatepieces of the die join together to form the cavity.die struck dimensiona dimension that is controlled exclu-sively by the dimensions of the steel die and not byprocessing.discolorationa streak or other pattern on the surface thatcauses a noticeable change of color from the rest of thepultruded surface.dry fibera condition in which fibers are not fully encapsu-lated by resin during pultrusion.dullnessa lack of normal pultruded surface gloss or shine.NOTE8This condition can be caused by insufficient cure locally or inlarge areas end cut angularity-The squareness of the end cut on a pultrudedshape measured in reference to a flat surface on the pultruded part whichis parallel to the direction of pull.dwarf widtha condition in which the crosswise(of thedirection of pultrusion)dimension of a flat surface of the partis less than that the die normally would yield for a particularcomposite.1These definitions are under the jurisdiction of ASTM Committee D20 onPlastics and are the direct responsibility of Subcommittee D20.18 on ReinforcedThermosetting Plastics.Current edition approved April 1,2011.Published April 2011.Originallyapproved in 1980.Last previous edition approved in 2003 as D3918-96(2003).DOI:10.1520/D3918-11.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 NOTE9This condition is usually caused by a partial blockage of thepultrusion die cavity caused by“build-up”or particles of the compositeadhering to the cavity surface.This condition is commonly called a“lostedge”when the flat surface has a free edge that is altered by the build-up.exposed underlayerthe underlying layer of mat or rovingnot covered by surface mat in a pultrusion.NOTE10This condition can be caused by reinforcement shifting,toonarrow surface mat,too wide underlying mat,uneven slitting of surfacemat,or ne