1、Designation:D380016Standard Test Method forDensity of High-Modulus Fibers1This standard is issued under the fixed designation D3800;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 ind
2、icates 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 U.S.Department of Defense.1.Scope1.1 This test method covers the determination of the densityof high-modulus fibers
3、and is applicable to both continuous anddiscontinuous fibers.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 This standard may involve hazardous materials,operations,and equipment.This standard does not purport toaddress
4、all of the safety concerns,if any,associated with itsuse.It is the responsibility of the user of this standard toestablish appropriate safety and health practices and deter-mine the applicability of regulatory limitations prior to use.See Section 9 for additional information.2.Referenced Documents2.
5、1 ASTM Standards:2D891 Test Methods for Specific Gravity,Apparent,of LiquidIndustrial ChemicalsD1505 Test Method for Density of Plastics by the Density-Gradient TechniqueD3878 Terminology for Composite MaterialsD5229/D5229M Test Method for MoistureAbsorption Prop-erties and Equilibrium Conditioning
6、of Polymer MatrixComposite MaterialsD6308 Guide for Identification of Composite Materials inComputerized Material Property Databases(Withdrawn1999)3E12 Terminology Relating to Density and Specific Gravityof Solids,Liquids,and Gases(Withdrawn 1996)3E177 Practice for Use of the Terms Precision and Bia
7、s inASTM Test Methods3.Terminology3.1 DefinitionsTerminology D3878 defines terms relatingto composite materials.Terminology E12 defines terms relatingto density.Practice E177 defines terms relating to statistics.Inthe event of a conflict between terms,Terminology D3878 shallhave precedence over othe
8、r standards.3.2 Symbols:3.2.1 sdensity of standard3.2.2 ldensity of liquid3.2.3 fdensity of fiber3.2.4 mfdensity of the measured fiber containing sizing3.2.5 mldensity of the measured liquid containing surfac-tant3.2.6 surdensity of surfactant3.2.7 szdensity of sizing3.2.8 wdensity of water3.2.9 sst
9、andard deviation3.2.10 M1weight of suspension wire in air3.2.11 M2weight of suspension wire in liquid(to immer-sion point)3.2.12 M3weight of suspension wire plus item whosedensity is to be determined(in air)3.2.13 M4weight of suspension wire plus item whosedensity is to be determined(in liquid)3.2.1
10、4 M3 M1weight of item for density to be deter-mined in air3.2.15 M4 M2weight of item for density to be deter-mined in liquid4.Summary of Test Method4.1 Procedure ABuoyancy(Archimedes)Method:4.1.1 The sample is weighed in air and weighed in a liquidthat will thoroughly wet the sample and is of a lowe
11、r density.4.1.2 The difference in weight of the sample in the twomedia is the buoyancy force.This force is converted to sample1This test method is under the jurisdiction of ASTM Committee D30 onComposite Materials and is the direct responsibility of Subcommittee D30.03 onConstituent/Precursor Proper
12、ties.Current edition approved Nov.1,2016.Published November 2016.Originallyapproved in 1979.Last previous edition approved in 2011 as D3800M 11.DOI:10.1520/D3800-16.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book o
13、f ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 volume
14、by dividing it by the liquid density.The sample weightin air divided by the sample volume equals the sample density.4.2 Procedure BSink-Float Technique:4.2.1 The sample is placed in a container containing a liquidthat will thoroughly wet the sample and is of a lower density.A liquid of higher densit
15、y than the sample and miscible withthe first liquid is then added slowly to the container underconstant gentle mixing until the sample is suspended in themixture.4.2.2 The density of the resulting mixed liquid is deter-mined using either a hydrometer or a pycnometer.The densityof the sample is equal
16、 to the density of the liquid in which thesample is suspended.4.3 Procedure CFor an alternative method,which may beused,see Test Method D1505.5.Significance and Use5.1 Fiber density is useful in the evaluation of new materialsat the research and development level and is one of the materialproperties normally given in fiber specifications.5.2 Fiber density is used to determine fiber strength andmodulus both of a fiber bundle and an individual filament.These properties are based on load or modulus
