ASTM_D_1415_-_06_2012.pdf

Designation:D141506(Reapproved 2012)Standard Test Method forRubber PropertyInternational Hardness1This standard is issued under the fixed designation D1415;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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 This test method covers a procedure for measuring thehardness of vulcanized or thermoplastic rubber.The hardnessis obtained by the difference in penetration depth of a specifieddimension ball under two conditions of contact with the rubber:(1)with a small initial force and(2)with a much larger finalforce.The differential penetration is taken at a specified timeand converted to a hardness scale value.1.2 This test method is technically similar to ISO 48.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1349 Practice for RubberStandard Conditions for Test-ingD2240 Test Method for Rubber PropertyDurometer Hard-nessD4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustries2.2 International Standard:3ISO48 Rubber,VulcanizedorThermoplasticDetermination of Hardness(Hardness between 10 and 100IRHD)3.Summary of Test Methods3.1 Four procedures are given to accommodate specimensof different dimensions hardness of vulcanized or thermoplas-tic rubbers on flat surfaces:Type S1 and S2,Standard hardness tests;Type M,Micro-hardness tests;Type L,Low hardness test;Type H,High hardness test.3.1.1 Types S1 and S2(refer to Table 1)The standard testfor hardness is the appropriate method for specimens having athickness described in Section 6,and is appropriate for thosehaving a hardness of 35 IRHD to 85 IRHD.It may be used forthose in the range of 30 IRHD to 95 IRHD.NOTE1The hardness values obtained by Types S and S1,within theranges of 85 IRHD to 95 IRHD and 30 IRHD to 35 IRHD may not agreewith those obtained using Types H or L.The differences are not generallyconsidered significant.3.1.2 Type M(refer to Table 1)The micro-hardness test isa scaled-down version of Type S1 and S2,which permit testingof thinner and smaller specimens.It is applicable for specimenshaving a thickness described in Section 6,and a hardness of 35IRHD to 85 IRHD.It may be used for those in the range of 30IRHD to 95 IRHD.NOTE2The hardness values obtained by Type M may not agree withthose obtained using Types S1 or S2 due to the effects of surface variationsor specimen configuration.3.1.3 Type LThe appropriate method for specimens hav-ing a thickness described in Section 6,and a hardness of 10IRHD to 35 IRHD.3.1.4 Type HThe appropriate method for specimens hav-ing a thickness described in Section 6,and a hardness of 85IRHD to 100 IRHD.3.2 In all procedures,the hardness in International RubberHardness Degrees(IRHD)is derived from the difference inpenetrations and a table or graph constructed from the table.Inthe micro-tester procedure,the difference in penetration mustfirst be multiplied by scale factor 6.Alternatively,the penetra-tion measuring instrument may be calibrated directly in IRHD.1This test method is under the jurisdiction of ASTM Committee D11 on Rubberand is the direct responsibility of Subcommittee D11.10 on Physical Testing.Current edition approved Jan.1,2012.Published March 2012.Originallyapproved in 1956.Last previous edition approved in 2006 as D1415 06.DOI:10.1520/D1415-06R12.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.Significance and Use4.1 The International Hardness test is based on measure-ment of the penetration of a rigid ball into the rubber specimenunder specified conditions.The measured penetration is con-verted into IRHD,the scale of degrees being so chosen that 0represents a material having an elastic modulus of zero,and100 represents a material of infinite elastic modulus.4.1.1 The scale also fulfills the following conditions overmost of the normal range of hardness:one IRHD rangerepresents approximately the same proportionate difference inYoungs modulus,and for rubber vulcanizates in the usualrange of resilience,readings in IRHD are comparable withthose given by a Type