ASTM D2653-2007(2012) Standard Test Method for Tensile Properties of Elastomeric Yarns (CRE Type Tensile Testing Machines)《弹性纱线抗拉伸特性的标准试验方法(CRE型拉伸试验机)》.pdf

《ASTM D2653-2007(2012) Standard Test Method for Tensile Properties of Elastomeric Yarns (CRE Type Tensile Testing Machines)《弹性纱线抗拉伸特性的标准试验方法(CRE型拉伸试验机)》.pdf》由会员分享，可在线阅读，更多相关《ASTM D2653-2007(2012) Standard Test Method for Tensile Properties of Elastomeric Yarns (CRE Type Tensile Testing Machines)《弹性纱线抗拉伸特性的标准试验方法(CRE型拉伸试验机)》.pdf（5页珍藏版）》请在麦多课文档分享上搜索。

1、Designation: D2653 07 (Reapproved 2012)Standard Test Method forTensile Properties of Elastomeric Yarns (CRE Type TensileTesting Machines)1This standard is issued under the fixed designation D2653; the number immediately following the designation indicates the year oforiginal adoption or, in the case

2、 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 This test method covers the determination of the tensileproperties of “as produced” elastome

3、ric yarns made fromnatural rubber, spandex or other elastomers, using a constant-rate-of-extension (CRE) type tensile testing machine. Theproperties included in this test method are: (1) force at firstfilament break, (2) tenacity at first filament break, (3) elonga-tion at first filament break, (4)

4、work to break at first filamentbreak, and (5) toughness at first filament break.1.2 This test method does not apply to covered, wrapped, orcore-spun yarns or yarns spun from elastomeric staple.1.3 This test method is applicable to elastomeric yarns in therange from 40 to 3200 dtex (36 to 2900 denier

5、).1.4 The values stated in either SI units or U.S. Customaryunits are to be regarded separately as standard. Within the text,the U.S. Customary units are given in parentheses. The valuesstated in each system are not exact equivalents; therefore, eachsystem shall be used independently of the other.1.

6、5 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 Doc

7、uments2.1 ASTM Standards:2D76 Specification for Tensile Testing Machines for TextilesD123 Terminology Relating to TextilesD1776 Practice for Conditioning and Testing TextilesD2258 Practice for Sampling Yarn for TestingD2591 Test Method for Linear Density of ElastomericYarns (Short Length Specimens)D

8、4848 Terminology Related to Force, Deformation andRelated Properties of TextilesD4849 Terminology Related to Yarns and FibersD6717 Test Method for Linear Density of ElastomericYarns (Skein Specimens)3. Terminology3.1 For all terminology relating to D13.58, Yarns andFibers, refer to Terminology D4849

9、.3.1.1 The following terms are relevant to this standard:elastomeric yarn, elongation, force, linear density, tenacity,toughness, work, work to break.3.2 For definitions of other terms related to force anddeformation, refer to Terminology D4848. For all other termi-nology related to textiles, refer

10、to Terminology D123.4. Summary of Test Method4.1 A specimen is clamped in a CRE-type tensile testingmachine and extended to rupture. Force at first filament breakand elongation at first filament break, work and toughness arecalculated from a force-elongation curve or with an interfacedcomputer. Tena

11、city at first filament break can be calculatedbased on the determined linear density of the yarn. Otherproperties, such as force at specified elongation (FASE),elongation at specified force (EASF), may also be calculated.5. Significance and Use5.1 This test method is considered satisfactory for acce

12、p-tance testing of commercial shipments since current estimatesof between-laboratory precision are acceptable and the methodis used extensively in the trade for acceptance testing.5.1.1 If there are differences of practical significance be-tween reported test results for two laboratories (or more),c

13、omparative tests should be performed to determine if there isa statistical bias between them, using competent statisticalassistance. As a minimum, use samples for such comparativetests that are as homogeneous as possible, drawn from the samelot of material as the samples that resulted in disparate r

14、esultsduring initial testing, and randomly assigned in equal numbersto each laboratory. The test results from the laboratoriesinvolved should be compared using a statistical test forunpaired data, at a probability level chosen prior to the testing1This test method is under the jurisdiction of ASTM C

15、ommittee D13 on Textilesand is the direct responsibility of Subcommittee D13.58 on Yarns and Fibers.Current edition approved July 1, 2012. Published August 2012. Originallyapproved in 1967. Discontinued 1979 and reinstated as D2653 79. Last previousedition approved in 2007 as D265307. DOI: 10.1520/D

16、2653-07R12.2For 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.1Copyright ASTM International, 100 Barr Harbor Dri

17、ve, PO Box C700, West Conshohocken, PA 19428-2959, United States.series. If bias is found, either its cause must be found andcorrected, or future test results for that material must beadjusted in consideration of the known bias.5.2 The force at first filament break of elastomeric yarnsmay depend on

18、its construction and manufacturing process andprovides an indication of the breaking strength of fabrics madefrom the yarn.5.3 Elongation is an indication of the ability of a fiber toabsorb energy. The elongation of yarn or fabric must be greatenough to withstand strains experienced in processing an

19、d enduse, and to absorb the energies of applied forces repeatedly.5.4 Fabric manufacturers use force and elongation informa-tion of elastomeric yarns in determining machine set-upconditions.5.5 Other parameters such as elongation at specified force(EASF), force (or tenacity) at specified elongation

20、(FASE,TASE), work and toughness may be calculated from force-elongation curves. EASF and FASE information is needed fortests involving cycling of yarn in determination of elasticproperties.5.6 This test method was developed using elastomeric yarnsin the “as-produced” condition, but may be used for t

21、reatedelastomeric yarns provided the treatment is specified. Themethod does not cover the removal of finish for determinationof tensile properties of “finish-free” elastomeric yarns.6. Apparatus36.1 Specimen Boards, with short pile or plush surfaces orblack or contrasting color, for storing specimen

22、s during con-ditioning.6.2 Tensile Testing Machine, CRE-type, conforming toSpecification D76 with respect to force indication, workingrange, capacity and verification of recorded elongation, anddesigned for operation at a pulling speed of 500 mm/min (20in./min) or 1000 % extension per min.6.3 Clampi

23、ng Assembly, pneumatically operated, with jawfaces as described in 6.3.1 or 6.3.2.6.3.1 Option A, PreferredOne jaw with a flat acrylic facenominally 25 mm 3 12.5 mm (1 in. 3 0.5 in.) and theopposing jaw approximately 12.5 mm (0.5 in.) wide with aconvex approximately 7.1 mm (0.28 in.) radius, steel o

24、rchrome face.6.3.2 Option BOne jaw with a flat, steel or chrome facenominally 25 mm 3 12.5 mm (1 in. 3 0.5 in.) and theopposing jaw approximately 12.5 mm (0.5 in.) wide with aconvex approximately 8.5 mm (0.375 in.) radius acrylic face.6.4 Computer or Microprocessor, interfaced, with auto-matic data

25、gathering system, optional.6.5 Tensioning Weights, with various masses from 10 mg to3 g as required to pretension the specimen to 30 to 50 mN/tex(0.3 to 0.5 mgf/d) before testing.6.6 Air Supply, capable of providing 415 kPa (60 psi) to thepneumatic clamps.7. Sampling, Test Specimens, and Test Units7

26、.1 Lot SampleAs a lot sample for acceptance testing,take a random number of shipping units directed in anapplicable material specification or other agreement betweenthe purchaser and the supplier, such as an agreement to usePractice D2258. Consider shipping cases or other shippingunits to be the pri

27、mary sampling units.NOTE 1An adequate specification or other agreement between thepurchaser and the supplier requires taking into account the variabilitybetween shipping units, between packages or ends within a shipping unit,and between specimens from a single package to provide a sampling witha mea

28、ningful producers risk, consumers risk, acceptable quality leveland limiting quality level.7.2 Laboratory SampleAs a laboratory sample for accep-tance testing, take at random from each shipping unit in the lotsample the number of packages directed in an applicablematerial specification or other agre

29、ement between the pur-chaser and the supplier, such as an agreement to use PracticeD2258. Preferably, take the same number of packages fromeach of the shipping units, determine at random which shippingunits are to have each number of packages for testing.7.3 Test SpecimensFrom each package or end in

30、 thelaboratory sample, take specimens as directed in 7.3.1.7.3.1 Remove the outer layer of yarn from the package.Avoid any damaged areas in selecting segments for testing.Carefully unwind yarn from the package with as low as tensionas possible to avoid stretching. As test specimens, cut approxi-mate

31、ly 125 mm (5 in.) long segments of yarn from eachpackage, taking them at intervals of at least1m(1yd). Threeof the six specimens are used as spare to allow for unacceptablebreaks, such as caused by slippage or breaking in the clamps.7.4 Determine the tex (denier) of the yarn for each labora-tory sam

32、ple using Test Method D2591 or Test Method D6717.8. Preparation of Apparatus8.1 Prepare and verify the calibration of the tensile testingmachine as directed in the manufacturers instructions.8.2 Set up and adjust the CRE-type tensile testing machineas follows:8.2.1 Examine the acrylic jaw face of th

33、e clamps for wearand replace as needed. Position the clamp faces with theircontact line horizontal.8.2.2 Set the distance between clamps, (gage length) to 506 1mm(26 0.05 in.), nip to nip.NOTE 2A convenient technique for checking the gage length is toplace a piece of carbon paper and white paper in

34、the clamps and close theclamps. The distance between the marks made on the white paper by thecarbon paper represents the set gage length.8.2.3 Use a force measuring system such that the breakingforce will fall between 30 and 80 percent of its full scalecapacity.8.2.4 Set the crosshead speed to 500 m

35、m/min (20 in./min) or1000 % extension per min.8.2.5 Set the extension measuring system as follows:8.2.5.1 When using a chart recorder, set the chart speed to500 mm/min (20 in./min). Not needed with computer inter-faced testing machines.3Apparatus and accessories are commercially available. Clamps ma

36、y need to bemodified to accept jaw faces and attachment to some tensile testing machine.D2653 07 (2012)28.2.5.2 When using an interfaced computer or microproces-sor, set parameters to obtain selected properties using suppli-ers directions and Specification D76.8.2.6 Set air pressure for pneumatic cl

37、amps to 415 kPa (60psi). At this pressure, the clamping force is approximately 450N (100 lb).9. Conditioning9.1 No preconditioning is required. for currently producedrubber yarns and other elastomeric yarns.9.2 Condition the specimens relaxed on specimen boards inthe standard atmosphere for testing

38、textiles as directed inPractice D1776 which is 21 6 1C (70 6 2F) and 65 6 2%relative humidity for a minimum of 4 h.10. Procedure10.1 Test the relaxed specimens in the standard atmospherefor testing textiles.NOTE 3The force measuring system should be zeroed prior to runningany specimens and periodica

39、lly during the course of the test, particularlyif drift is observed in the zero value of the force measuring system.10.2 Select the appropriate pretensioning weight based onthe linear density of the yarn that will provide a 30 to 50mN/tex (0.3 to 0.5 mgf/d) tension to the yarn.10.3 Attach the select

40、ed tensioning weight (10.2)tothespecimen such that when the specimen is place in the lowerclamp, the tensioning weight will hang freely.10.4 Position a specimen centrally between the top clampfaces and close the clamp. Ensure that the tensioning weight ishanging freely below the botton clamp.10.5 Cl

41、ose the lower clamp and remove the tensioningweight.10.6 Start the tester and observe the specimen behavior.Record the breaking force when the first filament break isobserved.10.6.1 If the specimen breaks within 3 mm (0.13 in.) ofeither jaw, or the slippage is indicated by a leveling in the forcedir

42、ection with abnormally high elongation, discard the resultand test another specimen from the same package.10.6.2 If many specimens exhibit what appears to be slip-page, replace the acrylic jaw face and retest.10.7 Remove the specimen and continue testing until a totalof 3 specimens have been tested

43、for each laboratory samplingunit.11. Calculation or Interpretation of Results11.1 Force at First Filament BreakCalculate the Force atFirst Filament Break (FFB) as follows:11.1.1 Read the force at FFB value to the nearest 0.1 cN (0.1gf) from the force elongation curve and record the value.NOTE 4In el

44、astomeric yarns, FFB is the first on the force-elongationcurve that is followed by a drop in force of at least 5 % of the force at thatpoint for this specimen or the equivalent in a computer algorithm.11.1.2 Calculate the average force at FFB for each labora-tory sampling unit and for the lot.11.2 T

45、enacity at First Filament BreakCalculate the Te-nacity at First Filament break as follows:11.2.1 Calculate the tenacity at FFB for each specimen tothe nearest 0.1 cN/tex (0.01 gf/d), using Eq 1.T 5 F/D (1)where:T = tenacity at FFB, cN/tex (gf/d),F = force at FFB, cN (gf), andD = average linear densi

46、ty, tex (denier).11.2.2 Calculate the average breaking tenacity for eachlaboratory sampling unit and for the lot.11.3 Percent Elongation at First Filament BreakCalculate the Percent Elongation at First Filament Break asfollows:11.3.1 Read the elongation at the force at FFB value foreach specimen to

47、the nearest 0.1 % from the force-elongationcurves.11.3.1.1 If force-extension curves are used, determine theextension corresponding to the force at FFB and calculate thepercent elongation at FFB, using Eq 2.E 5 100 3 L/G (2)where:E = elongation at FFB, %,L = the extension (distance on the extension

48、axis from theorigin to the extension line corresponding to the forceat FFB), mm (in.), andG = the nominal gage length, mm (in.).11.3.2 Calculate the average percent elongation at FFB foreach laboratory sampling unit and for the lot.11.4 Work to Break at First Filament Break (FFB)Calculate the Work t

49、o Break at FFB as follows:11.4.1 Using the force-extension curve, draw a line from thepoint of first filament break of each specimen perpendicular tothe extension axis. Measure the area bounded by the curve, theperpendicular, and the extension axis. This area may beestimated by counting squares, measured with a planimeter, ordetermined by electronic means.11.4.2 Calculate the work to break at FFB for each speci-men to the nearest. 0.01 mJ ( 0.01 in-lbf.), or the specific workto break at FFB to the nearest 0.01 J/m (0.01 in-lbf./in.) usingEq3orEq4.Wb5 A 3 F 3