ASTM D3106-2007(2018) Standard Test Method for Permanent Deformation of Elastomeric Yarns.pdf

1、Designation: D3106 07 (Reapproved 2018)Standard Test Method forPermanent Deformation of Elastomeric Yarns1This standard is issued under the fixed designation D3106; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last r

2、evision. 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 perma-nent deformation of bare, continuous elastomeric monofila-ments and f

3、ilament yarns made from rubber, spandex, anidex,or other elastomers subjected to prolonged periods of tension.This test method is applicable to elastomeric yarns having alinear density in the range from 4 to 320 tex (36 to 2900 den.).1.2 This test method is not applicable to covered, wrapped,core-sp

4、un yarns, or yarns spun from elastomeric staple.1.3 This test method was developed using yarns in the“as-received” condition, but may be used for treated yarnsprovided the treatment is specified.1.4 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are

5、for informationonly.1.5 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, health, and environmental practices and deter-mine the applicability of regulatory limi

6、tations prior to use.1.6 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization

7、 TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD2433 Test Methods for Rubber Thread (Withdrawn 2012)3D4849 Terminology Related to Yarns and Fibers3. Terminology3.1 For all terminology relating to D13.58, Yarns andFibers, re

8、fer to Terminology D4849.3.1.1 The following terms are relevant to this standard:breaking force, elastomeric yarn, elongation, elongation atbreak, extension, force, linear density, length distribution,permanent deformation, velveteen.3.2 For all other terminology related to textiles, refer toTermino

9、logy D123.4. Summary of Test Method4.1 The nominal linear density of the sample is known ordetermined and the elongation at the breaking force is deter-mined from representative specimens.4.2 A specimen from the sample is placed in a pair ofline-contact clamps and held at a selected elongation for a

10、specified period of time. The permanent deformation or non-recoverable stretch is measured after a specified recoveryperiod.5. Significance and Use5.1 Test Method D3106 for testing permanent deformationof elastomeric yarns is considered satisfactory for acceptancetesting of commercial shipments when

11、 there is prior agreementas to the exact value of elongation to be used for testing, sincecurrent estimates of between-laboratory precision are accept-able.5.1.1 If there are differences or practical significance be-tween reported test results for two laboratories (or more)comparative tests should b

12、e performed to determine if there isa statistical bias between them, using competent statisticalassistance. As a minimum, test samples that are as homoge-neous as possible, drawn from the material from which thedisparate test results were obtained, and randomly assigned inequal numbers to each labor

13、atory for testing. The test resultsfrom the two laboratories should be compared using a statis-tical test for unpaired data, at a probability level chosen priorto the testing series. If bias is found, either its cause must befound and corrected, or future test results for that material mustbe adjust

14、ed in consideration of the known bias.5.2 Yarns are subjected to long periods of tension resultingin an appreciable amount of stretch during normal use. Aportion of the induced stretch may be permanent. The amount1This test method is under the jurisdiction of ASTM Committee D13 on Textilesand is the

15、 direct responsibility of Subcommittee D13.58 on Yarns and Fibers.Current edition approved July 1, 2018. Published August 2018. Originallyapproved in 1972. Last previous edition approved in 2012 as D3106 07(2012).DOI: 10.1520/D3106-07R18.2For referenced ASTM standards, visit the ASTM website, www.as

16、tm.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.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International, 100 Barr

17、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 Recommen

18、dations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1of permanent deformation is influenced by the amount oftension, the time the yarn is under tension and the timeavailable for recovery between successive uses.5.3 For optimum processing of elastomeric yarns, t

19、he per-manent deformation value should be low or zero.6. Apparatus6.1 Line-Contact Clamps, with one fixed clamp and onemovable clamp, assembled as directed in Appendix X1, and asshown in Fig. 1.6.2 Tensioning Weights, 10 mg to 3 g, to pretension thespecimens before final clamping.NOTE 1Aluminum foil

20、 has been found to be suitable for use astensioning weights; the foil may be attached to the yarn by folding it overthe yarn.6.3 Stop Watch or Timer.7. Sampling7.1 Lot SampleAs a lot sample for acceptance testing, takeat random the number of shipping cartons of elastomeric yarnas directed in the app

21、licable material specification or otheragreement between the purchaser and supplier. Consider thematerial shipping carton to be the primary sampling unit.7.2 Laboratory SampleAs a laboratory sample for accep-tance testing, take at random the number of packages fromeach shipping carton in the lot sam

22、ple as directed in theapplicable material specification or other agreement betweenFIG. 1 Test Apparatus for Permanent SetD3106 07 (2018)2the purchaser and the supplier. If differing numbers andpackages are to be taken from the shipping cartons in the lotsample, determine at random which shipping car

23、tons are tohave each number of packages drawn.NOTE 2An adequate specification or other agreement between thepurchaser and the supplier requires taking into account the variabilitybetween shipping cartons, and the variability of the material within theshipping carton, to provide a sampling plan with

24、a meaningful producersrisk, consumers risk, acceptable quality level, and limiting quality level.7.3 Test SpecimensFrom each package in the laboratorysample, take the number of specimens directed in Section 8.Inspect each package after withdrawing at least five layers ofyarn from the outside of the

25、package. If there is evidence ofdamage, continue to withdraw units of five layers and reinspectuntil there is no discernible damage. Withdraw yarn over theend of the package and cut specimens approximately 150 mmlong. Discard specimens that are damaged during withdrawalor cutting. Withdraw at least2

26、mofyarn between specimensfrom a single package.8. Specimens Per Package8.1 Take a number of specimens per package such that theuser may expect at the 95 % probability level that the test resultis no more than 0.55 percentage points above or below the trueaverage of the package. Determine the number

27、of specimens asfollows:8.1.1 Reliable Estimate of sWhen there is a reliableestimate of s based on extensive past records for similarmaterials tested in the users laboratory as directed in the testmethod, calculate the required number of specimens perpackage using (Eq 1):n 5 ts/E!2(1)where:n = number

28、 of specimens per package (rounded upward to awhole number),s = reliable estimate of the standard deviation of individualobservations on similar materials in the users laboratoryunder conditions of single-operator precision,t = value of Students t for two-sided limits, a 95 %probability level, and t

29、he degree of freedom associatedwith the estimate of s (see Table 1), andE = 0.55 percentage points, the value of the allowablevariation.8.1.2 No Reliable Estimate of sWhen there is no reliableestimate of s for the users laboratory, (Eq 1) should not beused directly. Instead, specify the fixed number

30、 of ten speci-mens. This number of specimens is calculated using s = 0.87percentage point, which is a somewhat larger value of s than isusually found in practice. When a reliable estimate of s for theusers laboratory becomes available, (Eq 1) will usually requirefewer than ten specimens.9. Condition

31、ing9.1 Condition the specimens in the standard atmosphere fortesting textiles, 65 6 2 % relative humidity and 21 6 1C (706 2F) temperature, in moving air for a minimum time of 16h. Preconditioning is not necessary for the currently producedrubber and other elastomers having a moisture regain below1.

32、0 % and low moisture hysteresis.10. Procedure10.1 Test all specimens in the standard atmosphere fortesting textiles.10.2 Determine the elongation at the breaking force for eachspecimen as directed in Test Method D2433.NOTE 3When Test Method D3106 is used for acceptance testing, thelaboratory of the

33、purchaser and the laboratory of the supplier should agreeon a specific value of the elongation at the breaking force.10.3 Determine the linear density for the sample as directedin Test Method D2433. The nominal linear density value maybe used.10.4 Adjust the line-contact clamps for a 100 mm nominalg

34、age length (see Fig. 1). This is the original length of aspecimen.NOTE 4A convenient method for checking the gage length is to placea piece of carbon paper and white paper in the clamps and close theclamps. The distance between the marks on the whitepaper (made by thecarbon paper) is the nominal gag

35、e length. If the test apparatus isassembled as described in Appendix X1, the nominal gage length may beset directly.10.5 Fasten one end of the specimen in the top clamp. Passthe other end of the specimen through the lower clamp facesand through the toggle clamp. Attach a tensioning mass equalto 0.03

36、 mN/tex (0.3 6 0.1 mgf/den.) to the yarn below thelower clamp, allowing the yarn to hang freely between the jawsTABLE 1 Values of Students tAfor One-Sided and Two-Sided Limits and the 95 % Probability LeveldF One-sided Two-sided dF One-sided Two-sided dF One-sided Two-sided1 6.314 12.706 11 1.796 2.

37、201 22 1.717 2.0742 2.920 4.303 12 1.782 2.179 24 1.711 2.0643 2.353 3.182 13 1.771 2.160 26 1.706 2.0564 2.132 2.776 14 1.761 2.145 28 1.701 2.0485 2.015 2.571 15 1.753 2.131 30 1.697 2.0426 1.943 2.447 16 1.746 2.120 40 1.684 2.0217 1.895 2.365 17 1.740 2.110 50 1.676 2.0098 1.860 2.306 18 1.734 2

38、.101 60 1.671 2.0009 1.833 2.262 19 1.729 2.093 120 1.658 1.98010 1.812 2.228 20 1.725 2.086 1.645 1.960AValues in this table were calculated using Hewlett Packard HP 67/97 Users Library Programs 03848D, “One-sided and Two-sided Critical Values of Students t” and00350D,“ Improved Normal and Inverse

39、Distribution.” For values at other than the 95 % probability level, see published tables of critical values of Students t in any standardstatistical test (2), (3), (4), and (5).D3106 07 (2018)3of the lower clamp. Be sure the specimen remains in a verticalplane. Close the lower clamp and remove the t

40、ensioning mass.(See Note 1.)10.6 Lower the movable clamp to stretch the specimen60 % of the average breaking elongation calculated to thenearest 1 mm. Take about5stolower the clamp and hold thespecimen in this stretched condition for 10 6 1s.10.7 After the 10-s holding period, raise the lower clampu

41、ntil the specimen has a residual stretch of 20 % of the averagebreaking elongation calculated to the nearest 1 mm. Thismovement should take about 5 s. Hold the yarn in this positionfor4h6 10 min.NOTE 5Results have been found to be dependent upon the time tostretch as well as the amount of stretch im

42、parted to the yarn. It isrecommended that prior to actual testing, the operator familiarize himselfwith the rate of stretch required to effect the total required stretch withinthe specified time limit.10.8 At the end of the 4-h period, raise the lower clamp untilthe specimen has enough slack to prev

43、ent its coming undertension (becoming taut) as it recovers. Start the stop watch ortimer and hold the specimen in this condition for 10 min 6 30s.10.9 At the end of the recovery period, lower the moveableclamp until the specimen is just straight without beingstretched and measure the length of the s

44、pecimen to the nearest0.5 mm. The measured length is the stretched length of aspecimen after a 10-min relaxation time.10.10 Raise the lower clamp immediately after measuringthe specimen, allowing enough slack to prevent the specimenfrom becoming taut due to recovery. Hold the specimen in thisconditi

45、on for 100 6 5 min as measured by the stop watch ortimer.10.11 Remeasure the length of the specimen as directed in10.9. This is the stretched length of a specimen after a 100minrelaxation time.11. Calculation11.1 Calculate the permanent deformation to the nearest0.5 % using (Eq 2):Permanent deformat

46、ion, % 5 S 2 L!/L# 3100 (2)11.1.1 When L = 100 mm, (Eq 2) simplifies to the follow-ing:Permanent deformation, % 5 S 2 100 (3)where:S = stretched length of specimen at specified time, mm, andL = original length of specimen, mm.11.2 Calculate the average permanent deformation after10-min and 100-min r

47、elaxation times.11.3 Calculate the coefficient of variation, if requested.12. Report12.1 State that the specimens were tested as directed in TestMethod D3106. Describe the material or product sampled andthe method of sampling used.12.2 Report the following information:12.2.1 The average breaking elo

48、ngation,12.2.2 The average permanent deformation at 10-min and100min relaxation times to the nearest 0.5 %.12.2.3 The number of specimens tested, and12.2.4 The coefficient of variation, if calculated.13. Precision and Bias13.1 SummaryIn comparing two averages of fiveobservations, the differences sho

49、uld not exceed .8 percentagepoints of the grand average of all of the observations inapproximately 95 cases out of 100 when all of the observationsare taken by the same well-trained operator using the samepiece of test equipment and specimens drawn randomly fromthe same sample of material.13.2 Interlaboratory Test DataAn interlaboratory test wasrun in 1969, in which two laboratories tested five specimensfrom each of three materials. Each laboratory used oneoperator to test each material. The within-laboratory precisionand between-laboratory precisio