1、Designation: D 5170 98 (Reapproved 2004)Standard Test Method forPeel Strength (“T” Method) of Hook and Loop TouchFasteners1This standard is issued under the fixed designation D 5170; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、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 measurement of the peelstrength of hook and loop touch fasteners using a reco
3、rdingconstant-rate-of-extension tensile testing machine (CRE).1.2 The values stated in inch-pound units are to be regardedas the standard. The values given in parentheses are forinformation only.1.3 This standard does not purport to address all of thesafety problems, if any, associated with its use.
4、 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:2D 618 Practice for Conditioning Plastics for Testing3. Significance and Use3.
5、1 This test method gives a measure of a key property ofhook and loop touch fasteners which is of interest to users ofsuch devices. This is a means of determining the resistance toseparation when forces are applied normal to the line ofseparation of the fastener.3.2 The force registered in a peel tes
6、t is irregular, and as aconsequence, empirical methods have had to be developed toobtain usable values related to peel strength. In spite of theempirical nature of the reported values, it is believed theyreflect comparative performance of similar touch fastenerstested and measured in the same way.3.
7、3 Two optional methods of calculation are provided:integrator average and average of five highest peaks. These testmethods are not equivalent. Generally, the integrator averagewill be lower than the average of the five highest peaks.3.4 The highest peaks which reflect the force required toseparate a
8、 hook and loop closure bear no simple relationship tothe average force (integrator average). The average of the fivehighest peaks better reflect performance but the integratorresults may be used to characterize a closure and for qualitycontrol purposes. The integrator average is relatively easy toca
9、lculate given the proper equipment.3.5 In the case of a dispute arising from differences inreported test results when using this test method for acceptancetesting of commercial shipments, the purchaser and the sup-plier should conduct comparative tests to determine if there isa statistical bias betw
10、een their laboratories. Competent statis-tical assistance is recommended for the investigation of bias.As a minimum, the two parties should take a group of testspecimens which are as homogenous as possible and which arefrom a lot of hook and loop of the type in question. The testspecimens should the
11、n be randomly assigned in equal numbersto each laboratory for testing. The average results from the twolaboratories should be compared using Students t-test and anacceptable probability level chosen by the two parties beforethe testing began. If a bias is found, either its cause must befound and cor
12、rected or the purchaser and the supplier mustagree to interpret future test results in the light of the knownbias.4. Apparatus4.1 Rollerconsisting of a smooth steel surface, approxi-mately 434 in. (121 mm) in diameter, 214 in. (57 mm) wide,and equipped with a handle, length 418 in. (105 mm), forprop
13、elling the roller back and forth without adding additionalweight to the specimen being rolled (See Fig. 1). The weight ofthe roller (including the handle) is 11 614 lbs. (4994 g 6 114g).4.2 Testing MachineA constant rate of extension (CRE)tensile tester shall be used. The tester shall have two clamp
14、swith centers in the same plane, parallel to the direction of themotion of the stressing clamp, and so aligned that they willhold the specimen ends wholly in the same plane; a means ofmoving the stressing clamp at a uniform rate of 12.0 6 0.5in./min (305 6 13 mm/min), an autographic device for recor
15、d-ing the load; and provided with an integrator if the integratoraverage is to be used.1This test method is under the jurisdiction of ASTM Committee D13 on Textilesand is the direct responsibility of Subcommittee D13.54 on Subassemblies.Current edition approved Oct. 1, 2004. Published November 2004.
16、 Originallyapproved in 1991. Last previous edition approved in 1998 as D 5170 - 98.2For 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 pa
17、ge onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.2.1 The instrument shall be calibrated to an accuracy of1.0 % of the full scale and the scale range used for the test shallbe such that the main test falls withi
18、n 20 to 80 % of full range.5. Sampling5.1 Select the test samples so as to be as representative ofthe unit (a shipment, a lot, and so forth) as possible.5.2 LotA lot shall consist of all the material of the sametype, color and width, made at the same time from the samematerials in no more than a two
19、 week period. It shall beexpressed in linear units of 10 000 yards (9144 m).5.3 Sample RollsOne roll shall be randomly selected fromeach linear unit 10 000 yards (9144 m). If the lot does notcontain five units, additional rolls shall be selected from the lotto give a sample size of five rolls.5.4 Fo
20、r specification purposes, the material under test mustbe mated with material supplied by the manufacturer of thematerial being tested.6. Specimen Preparation6.1 Hook and loop material for this test shall be in the widthas supplied, not to exceed 1 in. (25.4 mm) in width. Formaterials greater than 1
21、in. (25.4 mm), a 1 in. (25.4 mm)specimen shall be slit from the center of the sample. If materialless than 1 in. (25.4 mm) wide is tested, test results will not bedirectly proportional to those obtained with the 1 in. (25.4 mm)wide material.6.1.1 Remove the outer layer of each roll before selectingt
22、he required number of strips, hook and loop, 8 in. 614 in.(203 6 6 mm) long.6.1.2 Each specimen is marked with an arrow () pointingin the direction that the specimen is unwound from the roll.This arrow is marked on the specimen on the leading end as itis unwound from the roll. The arrow () indicates
23、 the directionof the hooks and loops of the specimens.6.1.3 Select a sample consisting of four contiguous speci-mens as described in 8.1.2 and mark them with the appropriateidentification (roll number, lot number, date, and so forth).There are four possible direction configurations of closure asshow
24、n in Fig. 2. The four specimens of hook and loop selectedwill be used to characterize the peel strength of each of theconfigurations.7. Conditioning7.1 Condition the specimens in an atmosphere for testing of23 6 2C (73.4F 6 3.6F) and 50 6 5 % relative humidity, asdescribed in Practice D 618, for a p
25、eriod of 24 h or until thespecimens reach moisture equilibrium. Lay specimens flat withthe functional side up so that the conditioning atmosphere hasfree access to them.8. Procedure8.1 An initial closure is made and separated to raise theloops that might have been compressed in packaging.8.2 Select
26、from the four specimens of hook and loop, thefirst closure to be tested and referring to Fig. 2, prepare the firstclosure specimen with the marked arrows as shown in Se-quence 1.NOTE 1The reason for testing all four possible closure configurationsis that the hook or loop material, or both, may have
27、directionality (that is,the hooks or loops may not be perpendicular to the base fabric of whichthey are a component), and affect the peel force.FIG. 1 Roller for Making Closure of Hook and Loop TouchFasteners Prior to TestingFIG. 2 Test Configurations for “T” Peel Strength of Hook andLoop Fasteners
28、(Not to Scale)D 5170 98 (2004)28.2.1 Carefully align and superimpose the hook strip overthe loop strip so that the hook strip covers the loop strip, andthe marked ends are matched as shown in Fig. 2, Sequence 1.8.2.2 Place a flat steel plate 8 in. (20 cm) long and 112 in. (4cm) wide and weighing 4 p
29、ounds (1814 gm) (approximatelyequivalent to12 lbs per in2of closure) onto the closure,completely covering it, slowly, and without adding any handpressure. After 2 s remove the plate. This initial mating of theclosure is done to create just enough hook and loop engage-ment so as to be able to continu
30、e with the test procedure.8.2.3 Securely fasten the two ends of the mated hook andloop to a hard flat surface such as a metal plate, table top, etc.using masking tape, staples, clamps, hook and loop straps, orthe like.8.2.4 Push the roller without adding weight (from the end ofthe closure to be sepa
31、rated by the tensile tester) over the entirelength of the joined strips and then pull it back over the entirelength. This constitutes one cycle; a continuous uninterruptedback and forth motion of the roller, without lifting it from thematerial. Each cycle should take about 2 s.8.2.4.1 Perform five (
32、5) cycles with the roller without liftingit from the material. Remove the specimen from the holder,then hand separate this initial closure from the end indicated tobe joined in the tester clamps as indicated in Fig. 2, Sequence1.8.2.5 Then, again carefully align and superimpose the hookstrip over th
33、e loop strip so that the hook strip covers the loopstrip, and the marked ends, as described in 6.1.2, are matched.Then, again make the closure as described in 8.2.1-8.2.4,above. This will result in a “Ready for Peel Test” specimen.8.3 Prepare the second closure specimen as described in8.2.1-8.2.4 ex
34、cept with the marked ends as shown in Sequence2 of Fig. 2.8.4 Prepare the third closure specimen as described in8.2.1-8.2.4 except with the marked ends as shown in Sequence3 of Fig. 2.8.5 Prepare the fourth closure specimen as described in8.2.1-8.2.4 except with the marked ends as shown in Sequence4
35、 of Fig. 2.8.6 In the sequence in which the closure specimens wereprepared, select them for testing in the tensile tester. Gentlyseparate approximately one inch of closure at the end to beplaced into the clamps as indicated in Fig. 2 and in thesequence shown. This will create two free ends to be ins
36、ertedinto the tensile tester.8.7 Position the clamps of the tensile tester so they are1 618 in. (25.4 6 3 mm) apart. Place the free ends of thespecimen to be tested in the clamps of the tester with the hookstrip in the moving clamp. The point of separation should beapproximately centered and aligned
37、 approximately parallel tothe clamps. Use a clamp separation speed of 12.0 6 0.5 in./min(305 6 13 mm/min). If an integrator is used, set it such that thefirst and last inches of separation are not included in the results.8.8 Observe the chart paper produced by the autographicrecorder. A jagged line
38、having multiple peaks will be produced.Make note on the recording chart of the test specimen numberand sequence number from Fig. 2.9. Calculation9.1 Calculate the average peel force of the sample using the“average of five highest peaks” method.9.1.1 Mark five successive equal portions on the chartex
39、cluding the first and last inch of separation.9.1.2 Determine the highest peak value in each portion.9.1.3 Calculate the average of these five highest values foreach of the four specimens.9.1.4 Calculate the average of the values from the fourclosures representing the four configurations.9.2 Calcula
40、te the average peel force of the sample using the“Integrator” method.9.2.1 Calculate the average of the integrator values from thefour closures representing the four directions.9.2.2 Calculate the average of the values from each of thefive samples.9.3 If specimens less than 1 in. (25.4 mm) wide are
41、tested,record the average peel force and list the actual width.10. Report10.1 Report the following information:10.1.1 State that the specimens were tested as directed inASTM Test Method D 5170.10.1.2 Describe the material or product sampled (includingtype, color, source and manufacturers code or par
42、t number),10.1.3 The width of the material tested and whether thewidth was as supplied or slit down to 1 in. (25.4 mm) asrequired in 8.1,10.1.4 The calculation method used: that is, average of fivehighest peaks or integrator average,10.1.5 Average peel force per width of each sample to thenearest 0.
43、1 lb (.445 Newtons).11. Precision and Bias11.1 PrecisionBased on limited testing from one labora-tory using integrator averages, the within-laboratory or repeat-ability standard deviation is about 0.24 lb or the coefficient ofvariation is about 0.18. Repeatability is dependent on thespecific materia
44、l being tested; some materials would be ex-pected to be higher or lower than this. Between-laboratoryreproducibility is being determined by the subcommittee.11.2 BiasThe procedure in Test Method D 5170 for mea-suring the peel strength of hook and loop touch fasteners has nobias because the value of
45、the peel strength of hook and looptouch fasteners can be determined only in terms of a testmethod.12. Keywords12.1 fastener; hook and loop; hook; loop; peel; peelstrength; touch fastenerD 5170 98 (2004)3ASTM International takes no position respecting the validity of any patent rights asserted in con
46、nection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the respon
47、sible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful
48、consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 1
49、00 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 5170 98 (2004)4
