1、Designation: D1294 05 (Reapproved 2013)Standard Test Method forTensile Strength and Breaking Tenacity of Wool FiberBundles 1-in. (25.4-mm) Gage Length1This standard is issued under the fixed designation D1294; the number immediately following the designation indicates the year oforiginal adoption or
2、, 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.1. Scope1.1 This test method covers the determination of the break-ing force (or load) and
3、estimation of the 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
4、 the instrument 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 D1445 and D2524.NOTE 2This test method can be used for other fibers that lendthemselves to
5、 the same kind 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
6、any, associated 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 f
7、or TextilesD123 Terminology Relating to TextilesD1445 Test Method for Breaking Strength and Elongation ofCotton Fibers (Flat Bundle Method)D1776 Practice for Conditioning and Testing TextilesD2524 Test Method for Breaking Tenacity of Wool Fibers,Flat Bundle Method18-in. (3.2-mm) Gage LengthD2525 Pra
8、ctice for Sampling Wool for MoistureD4845 Terminology Relating to Wool3. Terminology3.1 For all terminology related to Wool and Wool Felt,D13.13, refer to Terminology D4845.3.1.1 The following terms are relevant to this standard: gagelength, recycled wool, tenacity, tensile strength, wool (asdefined
9、 in the Wool Products Labeling Act of 1939).3.2 For all other terminology related to textiles see Termi-nology D123.4. 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
10、tape. A 1-in. (25.4-mm) spacing between the tapes (and clamps at the zero setting)makes 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. Significanc
11、e and Use5.1 Test Method D1294 for the determination of tensilestrength may be used for 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
12、 are differences of practical significance be-tween reported test results for two laboratories (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 tha
13、t are as homogenous as possible, drawn from the samelot of material as the samples that 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
14、 data, a probability level chosen prior to the testingseries. 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.1This test method is under the jurisdiction ofASTM Committee D13 on Textilesand is
15、the direct responsibility of Subcommittee D13.13 on Wool and Felt.Current edition approved Jan. 1, 2013. Published January 2013. Originallyapproved in 1953. Last previous edition approved in 2005 as D1294 05. DOI:10.1520/D1294-05R13.2For referenced ASTM standards, visit the ASTM website, www.astm.or
16、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.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15.2 This test
17、method is useful in studying the relationshipbetween fiber strength and product quality; results should 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 Elon
18、gation may be obtained also but the accuracy ofelongation measurements is limited and their determination 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 D2524 are in thegage lengths
19、 employed and the methods of clamping. In TestMethod D2524, specific clamps are required whereas in TestMethod D1294, any conventional clamps may be used. Resultsfor breaking load determined by Test Method D2524 average30 % higher than those obtained by Test Method D1294.6. Apparatus and Materials6.
20、1 Comb, fine, sharp.36.2 Analytical Balance, with a sensitivity of 0.0001 g.6.3 Tensile Testing 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 CRLt
21、ypemachine is used, it should be capable of operating at a rate ofloading of 1 kgf/s (10 N/s). 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
22、.Consequently, these three machines cannot be used interchangeably.6.4 Metal Plates, 2 by 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 a
23、rerequired to prepare a bundle for testing.NOTE 4These plates can be made by gluing rubber 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
24、 shipment of a singlefiber type as a lot.7.2 Lot SampleAs a lot sample for acceptance testing, takeat random the number of shipping containers directed in anapplicable material specification or other agreement betweenthe purchaser and the supplier, such as an agreement to usePractice D2525. Consider
25、 shipping containers to be the pri-mary sampling units.7.3 Laboratory SampleFor acceptance 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 1
26、5 gby randomly selecting pieces throughout the mass. Form into aloose sliver by hand.7.3.2 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
27、 include all ends.7.4 Test SpecimensScour or solvent-extract the laboratorysample until residual 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 i
28、n 9.1.8. Preconditioning and Conditioning8.1 Bring the laboratory sample to moisture equilibrium fortesting in the standard atmosphere for testing textiles, asdirected in Practice D1776.9. Preparation of Specimens9.1 Prepare each specimen by drawing small groups offibers from at least five locations
29、 in a unit of the laboratorysample. Parallelize and combine them in a bundle which maybe 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 a
30、nd 25 mg.9.2 Transfer one end of the bundle to the hand vise andcomb the rest of the bundle 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 m
31、ay have to berepeated several times until the fibers are parallel.9.4 Tension the fibers 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. Maint
32、ainpressure between these two plates, first by hand and then byvise (Fig. 5), until the 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
33、 theprotruding fibers as evenly as possible while laying themacross the masking tape. The 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-sph
34、ere for testing textiles.10.2 Insert the conditioned test specimen in the testingmachine using a gage length of 1 in. (25.4 mm) and break thetest specimen in accordance with the manufacturers instruc-tions.3The comb and hand vise supplied with the Suter Sorter wool fiber staplingapparatus are suitab
35、le for this test method and are available from the Alfred SuterCo., Inc., Prel Plaza, Orangeburg, NY 10962.D1294 05 (2013)210.3 After the specimen has been broken, record the break-ing force (or load).10.4 Cut the fibers with a razor blade at the edge of eachclamp and place the fibers in a weighing
36、bottle.10.5 Weigh and record the mass to the nearest 0.0001 g.11. Calculation11.1 Calculate the 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) (tenacity incentinewtons per tex (cN/tex) is numerically
37、 equal to tenacityFIG. 1 Combing of BundleFIG. 2 Tensioning of FibersFIG. 3 Laying the Fibers Across PlateD1294 05 (2013)3in grams-force per tex) calculated using Eq 1 or in tensilestrength (pounds force per square inch) using Eq 2, whicheveris desired (see Appendix).Breaking tenacity, gf/tex 5 B/M!
38、 30.01152 (1)Tensile strength, lbf/in. 5 B/M! 321.47 (2)where:B = bundle breaking load, lbf, andM = bundle mass, g.If the testing machine is graduated in grams:Breaking tenacity, gf/tex 5 b/M! 32.540 31025(3)Tensile strength, lbf/in.25 b/M! 34.733 31022(4)where:b = bundle breaking load, gf, andM = b
39、undle mass, g.12. Report12.1 State that the specimens were tested as directed inASTM Test Method D1294. Describe the material(s) or prod-uct(s) sampled and the method of sampling used. Describe thetensile testing machine and operating specifications.12.2 Report the following information:12.2.1 Avera
40、ge tensile strength in gf/tex to one decimalplace or mN/tex to the nearest whole number,12.2.2 Average tensile strength in lbf/in.2to three significantfigures,12.2.3 Estimated standard deviation or coefficient ofvariation, if calculated, and12.2.4 The number of specimens tested.13. Precision and Bia
41、s13.1 Interlaboratory Test DataAn interlaboratory test wasrun in 1962 in which randomly drawn samples of three types ofFIG. 4 Placing of Second PlateFIG. 5 Maintaining the PressureD1294 05 (2013)4wool were tested in six laboratories. Each laboratory used oneoperator who tested five specimens of each
42、 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 listed inTable 1, two averages of observed values should be consideredsignificantly different at the 95 % probability level i
43、f 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 particularly with respect to between-laboratory precision. Before a meaningful statement can be made abouttwo specific laborator
44、ies, 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 sample of thematerial to be tested.FIG. 6 Applying Masking TapeFIG. 7 Final BundlesTABLE 1 Components of Variance as Coefficients
45、 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 AverageSingle-OperatorP
46、recisionBetween-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 on infinitedegrees of freedom.BTo convert the values of the critica
47、l differences to units of measure, multiply theaverage of the two specific sets of data being compared by the critical differencesexpressed as a decimal fraction.D1294 05 (2013)513.3 BiasThe value of breaking strength of wool fiberbundles can be defined only in terms of a specific test method.Within
48、 this limitation, Test Method D1294 has no known bias.14. Keywords14.1 breaking strength; woolAPPENDIX(Nonmandatory Information)X1. BASIS OF EQUATIONS FOR BREAKING TENACITY AND TENSILE STRENGTHX1.1 Eq X1.1 and Eq X1.2 below include all of the factorsneeded to calculate breaking tenacity and tensile
49、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/tex (X1.1)5 2.54 3453.6 3BL!/100 31000 3M!Tensile strength, lbf/in.25 2.54!33 GLB/M! (X1.2)where:G = density, taken as 1.31 g/cm3for wool (when this testis used for fibers other than wool, the appropriatevalue 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, mu
