1、Designation: D 1294 05Standard Test Method forTensile Strength and Breaking Tenacity of Wool FiberBundles 1-in. (25.4-mm) Gage Length1This standard is issued under the fixed designation D 1294; the number immediately following the designation indicates the year oforiginal adoption or, in the case of
2、 revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of the break-ing force (or load) and estimation of t
3、he tensile strength andtenacity of wool fiber bundles with a 1-in. (25.4-mm) gagelength. A procedure for preparation of the fiber bundle isincluded.1.2 The values stated in inch-pound units are to be regardedas standard; the values in SI units are provided for informationonly. Because the instrument
4、 is calibrated in inch-pound units,inch-pound units are shown first, contrary to Committee D13policy.NOTE 1For other methods of measuring breaking tenacity of fiberbundles, refer to Test Methods D 1445 and D 2524.NOTE 2This test method can be used for other fibers that lendthemselves to the same kin
5、d of preparation but the difference in densitymust be taken into account when calculating the tensile strength. It is notnecessary to know or correct for the density of a fiber when calculatingbreaking tenacity.1.3 This standard does not purport to address all of thesafety concerns, if any, associat
6、ed with its use. It is theresponsibiltiy 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:2D76 Specification for Tensile Testing Machines for TextilesD
7、123 Terminology Relating to TextilesD 1445 Test Method for Breaking Strength and Elongationof Cotton Fibers (Flat Bundle Method)D 1776 Practice for Conditioning and Testing TextilesD 2524 Test Method for Breaking Tenacity of Wool Fibers,Flat Bundle Method18-in. (3.2-mm) Gage LengthD 2525 Practice fo
8、r Sampling Wool for MoistureD 4845 Terminology for Wool3. Terminology3.1 For all terminology related to Wool and Wool Felt,D13.13, refer to Terminology D 4845.3.1.1 The following terms are relevant to this standard: gagelength, recycled wool tenacity, wool.3.2 For all other terminology related to te
9、xtiles see Termi-nology D 123.4. Summary of Test Method4.1 The strength determination is based on the load requiredto break a bundle of fibers which had been parallelized andheld under uniform tension with masking tape. A 1-in. (25.4-mm) spacing between the tapes (and clamps at the zero setting)make
10、s possible the cutting and weighing of this amount of fiberfor use in calculating the strength expressed as breakingtenacity in grams-force per tex or tensile strength in pounds-force per square inch.5. Significance and Use5.1 Test Method D 1294 for the determination of tensilestrength may be used f
11、or the acceptance testing of commercialshipments of wool, but caution is advised since techniciansmay fail to get good agreement between results. Comparativetests as directed in 5.1.1 may be advisable.5.1.1 If there are differences of practical significance be-tween reported test results for two lab
12、oratories (or more),comparative test should be performed to determine if there is astatistical bias between them, using competent statistical assis-tance. As a minimum, use the samples for such a comparativetest that are as homogenous as possible, drawn from the samelot of material as the samples th
13、at resulted in disparate resultsduring 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, a probability level chosen prior to the testingseries. If bias is found, eithe
14、r its cause must be found andcorrected, or future test results for that material must beadjusted in consideration of the known bias.1This test method is under the jurisdiction ofASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.13 on Wool and Wool Felt.Current editio
15、n approved April 1, 2005. Published May 2005. Originallyapproved in 1953 . Last previous edition approved in 2001 as D 1294 95a(2001).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume info
16、rmation, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.2 This test method is useful in studying the relationshipbetween fiber strength and product quality; results s
17、hould beconsidered comparative rather than fundamental since thestrength found will be lower than the sum of the strengths ofthe individual fibers present due to slight differences intensioning.5.3 Elongation may be obtained also but the accuracy ofelongation measurements is limited and their determ
18、ination is,therefore, not included as a formal part of this test method.5.4 The basic differences between the procedures employedin this test method and those of Test Method D 2524 are in thegage lengths employed and the methods of clamping. In TestMethod D 2524, specific clamps are required whereas
19、 in TestMethod D 1294, any conventional clamps may be used. Re-sults for breaking load determined by Test Method D 2524average 30 % higher than those obtained by Test MethodD 1294.6. Apparatus and Materials6.1 Comb, fine, sharp.36.2 Analytical Balance, with a sensitivity of 0.0001 g.6.3 Tensile Test
20、ing Machine, a CRE or CRT Type about50-lb (22-kg) capacity machine as prescribed in SpecificationD76, capable of operating the moving clamp at a uniformspeed of 10.0 6 0.5 in./min (250 6 12 mm/min). If a CRLtypemachine is used, it should be capable of operating at a rate ofloading of 1 kgf/s (10 N/s
21、). In no case shall the working rangebe outside the limits recommended by the manufacturer.NOTE 3There may be no overall correlation between the resultsobtained with the CRE, CRT, or CRL type testing machines. Conse-quently, these three machines cannot be used interchangeably.6.4 Metal Plates, 2 by
22、1-in. (50.8 by 25.4-mm) with onerubber-covered surface. The plates should be rigid, flat, andapproximately 0.1 in. (2.5 mm) thick with one rubber faceapproximately 0.06 in. (1.5 mm) thick (Note 4). Two plates arerequired to prepare a bundle for testing.NOTE 4These plates can be made by gluing rubber
23、 sheeting approxi-mately 0.06 in. (1.5 mm) thick to the face of the plate.6.5 Hand Vise,3preferably of the spring-type.6.6 Masking Tape, 2-in. (50-mm) wide, heavy.7. Sampling7.1 Division into LotsTreat a single shipment of a singlefiber type as a lot.7.2 Lot SampleAs a lot sample for acceptance test
24、ing,take at random the number of shipping containers directed inan applicable material specification or other agreement be-tween the purchaser and the supplier, such as an agreement touse Practice D 2525. Consider shipping containers to be theprimary sampling units.7.3 Laboratory SampleFor acceptanc
25、e testing, take alaboratory sample from each shipping container in the lotsample as follows:7.3.1 For loose fiber, grease, and scoured wool, reduce themass of clean fiber submitted for testing to approximately 15 gby randomly selecting pieces throughout the mass. Form into aloose sliver by hand.7.3.
26、2 For card sliver and top, cut a length of sliver about 20in. (500 mm) long from each ball submitted for testing.7.3.3 For roving, cut a length about 20 in. (500 mm) longfrom each spool submitted for testing and include all ends.7.4 Test SpecimensScour or solvent-extract the laboratorysample until r
27、esidual contamination is 1 % or less of thelaboratory mass, as established by further cleaning of a part ofthe laboratory sample. From each unit in the laboratory sample,prepare five test specimens as directed in 9.1.8. Preconditioning and Conditioning8.1 Bring the laboratory sample to moisture equi
28、librium fortesting in the standard atmosphere for testing textiles, asdirected in Practice D 1776.9. Preparation of Specimens9.1 Prepare each specimen by drawing small groups offibers from at least five locations in a unit of the laboratorysample. Parallelize and combine them in a bundle which maybe
29、 held conveniently between the thumb and forefinger.Choose the size of the bundle so that in the final bundle the1-in. (25.4-mm) length of fiber between the clamps of thetesting machine has a mass of between 15 and 25 mg.9.2 Transfer one end of the bundle to the hand vise andcomb the rest of the bun
30、dle to remove the short fibers and toparallelize the remainder (see Fig. 1).9.3 Transfer the hand vise to the other end of the bundle andrepeat the combing operation.NOTE 5The procedure described in 9.2 and 9.3 may have to berepeated several times until the fibers are parallel.9.4 Tension the fibers
31、 between the vise and the fingers asuniformly as possible (Fig. 2) and lay them across therubber-faced plate (Fig. 3). On top of this plate and the fibers,place a second plate (Fig. 4) and hold it in place. Maintainpressure between these two plates, first by hand and then byvise (Fig. 5), until the
32、masking tape is applied. Apply 1-in.(25.4-mm) squares of heavy masking tape to the protrudingends on each side of the plates on both top and bottom surfacesof the bundle (Fig. 6). During this application, tension theprotruding fibers as evenly as possible while laying themacross the masking tape. Th
33、e final bundles should look likethose shown in Fig. 7 with a 1-in. (25.4-mm) spacing betweenthe tapes. The specimens are now ready to test.10. Procedure10.1 Test the conditioned specimens in the standard atmo-sphere for testing textiles.10.2 Insert the conditioned test specimen in the testingmachine
34、 using a gage length of 1 in. (25.4 mm) and break thetest specimen in accordance with the manufacturers instruc-tions.10.3 After the specimen has been broken, record the break-ing force (or load).3The comb and hand vise supplied with the Suter Sorter wool fiber staplingapparatus are suitable for thi
35、s test method and are available from the Alfred SuterCo., Inc., Prel Plaza, Orangeburg, NY 10962.D129405210.4 Cut the fibers with a razor blade at the edge of eachclamp and place the fibers in a weighing bottle.10.5 Weigh and record the mass to the nearest 0.0001 g.11. Calculation11.1 Calculate the
36、average breaking force (or load) for a1-in. (25.4-mm) bundle length. The strength may be expressedeither in breaking tenacity (grams force per tex) calculatedusing Eq 1 or in tensile strength (pounds force per square inch)using Eq 2, whichever is desired (see Appendix).Breaking tenacity, gf/tex 5 B/
37、M! 3 0.01152 (1)Tensile strength, lbf/in. 5 B/M! 3 21.47 (2)FIG. 1 Combing of BundleFIG. 2 Tensioning of FibersFIG. 3 Laying the Fibers Across PlateD1294053where:B = bundle breaking load, lbf, andM = bundle mass, g.If the testing machine is graduated in grams:Breaking tenacity, gf/tex 5 b/M! 3 2.540
38、 3 1025(3)FIG. 4 Placing of Second PlateFIG. 5 Maintaining the PressureFIG. 6 Applying Masking TapeD1294054Tensile strength, lbf/in.25 b/M! 3 4.733 3 1022(4)where:b = bundle breaking load, gf, andM = bundle mass, g.12. Report12.1 State that the specimens were tested as directed inASTM Test Method D
39、1294. Describe the material(s) orproduct(s) sampled and the method of sampling used. Describethe tensile testing machine and operating specifications.12.2 Report the following information:12.2.1 Average tensile strength in gf/tex to one decimalplace or mN/tex to the nearest whole number,12.2.2 Avera
40、ge tensile strength in lbf/in.2to three significantfigures,12.2.3 Estimated standard deviation or coefficient of varia-tion, if calculated, and12.2.4 The number of specimens tested.13. Precision and Bias13.1 Interlaboratory Test DataAn interlaboratory test wasrun in 1962 in which randomly drawn samp
41、les of three types ofwool were tested in six laboratories. Each laboratory used oneoperator who tested five specimens of each type of wool. Thecomponents of variance expressed as coefficients of variationwere calculated to be the values listed in Table 1.13.2 PrecisionFor the components of variance
42、listed inTable 1, two averages of observed values should be consideredsignificantly different at the 95 % probability level if thedifference equals or exceeds the critical values listed in Table2.NOTE 6The tabulated values of the critical differences should beconsidered to be a general statement par
43、ticularly with respect to between-laboratory precision. Before a meaningful statement can be made abouttwo specific laboratories, the amount of statistical bias, if any, betweenthem must be established, with each comparison being based on recentdata obtained on specimens randomly drawn from one samp
44、le of thematerial to be tested.13.3 BiasThe value of breaking strength of wool fiberbundles can be defined only in terms of a specific test method.Within this limitation, Test Method D 1294 has no known bias.14. Keywords14.1 breaking strength; woolFIG. 7 Final BundlesTABLE 1 Components of Variance a
45、s Coefficients of Variation,Percent of the AverageType of WoolSingle-OperatorComponentBetween-LaboratoryComponent64s wool 6.2 5.846s wool 5.2 9.0Uruguay wool 6.4 9.7TABLE 2 Critical Differences for the Conditions Noted,A,BPercent of the Grand AverageType of WoolNumber ofObservations inEach AverageSi
46、ngle-OperatorPrecisionBetween-LaboratoryPrecision64s wool 1 17.2 23.54 8.6 18.28 6.1 17.246s wool 1 14.4 28.84 7.2 26.08 5.1 25.5Uruguay wool 1 17.7 32.24 8.9 28.38 6.3 27.6AThe critical differences were calculated using t = 1.960, which is based oninfinite degrees of freedom.BTo convert the values
47、of the critical differences to units of measure, multiply theaverage of the two specific sets of data being compared by the critical differencesexpressed as a decimal fraction.D1294055APPENDIX(Nonmandatory Information)X1. BASIS OF EQUATIONS FOR BREAKING TENACITY AND TENSILE STRENGTHX1.1 Eq X1.1 and
48、Eq X1.2 below include all of the factorsneeded to calculate breaking tenacity and tensile strength.Assuming a length of 1 in. (25.4 mm) and a density of 1.31, theequations can be reduced to those presented as Eq X1.1 and EqX1.2.Breaking tenacity, gf/tex5 2.54 3 453.6 3 BL!/100 3 1000 3 M!(X1.1)Tensi
49、le strength, lbf/in.25 2.54!33 GLB/M! (X1.2)where:G = density, taken as 1.31 g/cm3for wool (when thistest is used for fibers other than wool, the appro-priate value of density should be used),L = bundle length, in.,B = bundle breaking load, lbf,M = bundle mass, g, and2.54 = conversion factor from in. to cm.NOTE X1.1To convert lbf/in.2to gf/tex, multiply lbf/in.2by53.25 3 105.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are express
