1、Designation:D677921Standard Classification System for and Basis of Specification forPolyamide Molding and Extrusion Materials(PA)1This standard is issued under the fixed designation D6779;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revisi
2、on,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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope*1.1 This classification sy
3、stem covers polyamide materialssuitable for molding and extrusion.Some of these composi-tions are also suitable for application from solution.1.2 The properties included in this classification system arethose required to identify the compositions covered.Otherrequirements necessary to identify parti
4、cular characteristicsimportant to specialized applications are to be specified byusing suffixes as given in Section 5.1.3 This classification system and subsequent line callout(specification)are intended to provide a means of calling outplastic materials used in the fabrication of end items or parts
5、.It is not intended for the selection of materials.Materialselection can be made by those having expertise in the plasticfield after careful consideration of the design and the perfor-mance required of the part,the environment to which it will beexposed,the fabrication process to be employed,the cos
6、tsinvolved,and the inherent properties of the material other thanthose covered by this classification system.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.5 The following precautionary caveat pertains only to thetest meth
7、ods portion,Section 11,of this classification system.This standard does not purport to address all of the safetyconcerns,if any,associated with its use.It is the responsibilityof the user of this standard to establish appropriate safety,health,and environmental practices and determine the appli-cabi
8、lity of regulatory limitations prior to use.NOTE1This classification system is similar to ISO 16396-1-2,although the technical content is significantly different.1.6 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in
9、 the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D257 Test Methods for DC Resistance or Conductance ofInsulating MaterialsD78
10、9 Test Method for Determination of Relative Viscosityof Concentrated Polyamide(PA)SolutionsD792 Test Methods for Density and Specific Gravity(Rela-tive Density)of Plastics by DisplacementD883 Terminology Relating to PlasticsD1600 Terminology forAbbreviated Terms Relating to Plas-ticsD3892 Practice f
11、or Packaging/Packing of PlasticsD4000 Classification System for Specifying Plastic Materi-alsD5740 Guide for Writing Material Standards in the Classi-fication FormatD6260 Test Method for Gravimetric Determination of Car-bon Black in Nylon Materials(PA)(Withdrawn 2004)3D7209 Guide for Waste Reduction
12、,Resource Recovery,andUse of Recycled Polymeric Materials and Products(With-drawn 2015)3E29 Practice for Using Significant Digits in Test Data toDetermine Conformance with Specifications2.2 IEC/ISO Standards:4IEC 60243-1 Electrical Strength of Insulating MaterialsTest MethodsPart 1:Tests at Power Fr
13、equenciesIEC 60250 Recommended Methods for the Determination ofthe Permittivity and Dielectric Dissipation Factor ofElectrical Insulating Materials at Power,Audio and RadioFrequencies Including Metre Wavelengths1This classification system is under the jurisdiction ofASTM Committee D20 onPlastics and
14、 is the direct responsibility of Subcommittee D20.15 on ThermoplasticMaterials.Current edition approved July 1,2021.Published July 2021.Originally approvedin 2002.Last previous edition approved in 2020 as D6779-20.DOI:10.1520/D6779-21.2For referenced ASTM standards,visit the ASTM website,www.astm.or
15、g,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of 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.4Available from American National Standards Ins
16、titute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World
