1、Designation: D 4032 08Standard Test Method forStiffness of Fabric by the Circular Bend Procedure1This standard is issued under the fixed designation D 4032; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、 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 stiff-ness of fabrics by the circular bend procedure.1.2 This test method is genera
3、lly applicable to all types offabrics, including woven, knitted and nonwovens, of any fibercontent.NOTE 1For other methods of testing for stiffness, refer to TestMethods D 1388.1.3 The values stated in SI units are to be considered asstandard; the values in inch-pound units are included forinformati
4、on only.1.4 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. Refe
5、renced Documents2.1 ASTM Standards:2D 123 Terminology Relating to TextilesD 1388 Test Method for Stiffness of FabricsD 1776 Practice for Conditioning and Testing TextilesD 4850 Terminology Relating to Fabric3. Terminology3.1 For all terminology relating to D13.60, Fabric TestMethods, Specific, refer
6、 to Terminology D 4850.3.1.1 The following terms are relevant to this standard:circular bend, stiffness.3.2 For all other terminology related to textiles, see Termi-nology D 123.4. Summary of Test Method4.1 A plunger forces a flat, folded swatch of fabric throughan orifice in a platform. The maximum
7、 force required to pushthe fabric through the orifice is an indication of the fabricstiffness (resistance to bending).5. Significance and Use5.1 Test Method D 4032 for testing stiffness of fabrics isconsidered satisfactory for quality control testing. It may alsobe used for acceptance testing of com
8、mercial shipments sincethe test method has been used extensively in the trade field. Incases of differences in values reported by purchaser and sellerusing Test Method D 4032 for acceptance testing, the statisticalbias, if any, between the laboratories of the purchaser and theseller should be determ
9、ined with each comparison being basedon the testing of specimens taken homogeneously from a lot ofmaterial of the type being evaluated. Specimens should berandomly assigned in equal numbers to each of the laborato-ries.5.2 The circular bend procedure gives a force value relatedto fabric stiffness, s
10、imultaneously averaging stiffness in alldirections. The stiffness tests in Test Methods D 1388 are of thesingle directional type.5.3 The circular bend procedure is simple to perform andmay be used for knitted, woven, or nonwoven fabrics, providedgage capacity is in keeping with fabric range tested.6
11、. Apparatus6.1 Circular Bend Stiffness Tester,3(Figs. 1 and 2), havingthe following parts:6.1.1 Platform,102by102by6mm(4by4by14 in.)smooth-polished chrome-plated steel plate with a 38.1-mm(1.50-in.) diameter orifice. The lap edge of the orifice should beat a 45 angle to a depth of 4.8 mm (316 in.) (
12、see Fig. 3).6.1.2 Plunger, 25.4-mm (1.00-in.) diameter, mounted con-centric with orifice, 6.4 mm (0.25 in.) clearance on all sides.The bottom of the plunger should be set at 3 mm (18 in.) abovethe top of the orifice plate. From this position, the downwardstroke length is 57 mm (214 in.).6.1.3 Force-
13、Measurement Gage, dial or digital type (see9.3).6.1.3.1 Dial gages with maximum reading pointer in differ-ent capacities ranging from 1 to 50 lbf, 0.5 to 25 kgf, or 5 to200 N with 100 graduations minimum; or1This test method is under the jurisdiction of ASTM Committee D13 on Textilesand is the direc
14、t responsibility of Subcommittee D13.60 on Fabric Test Methods,Specific.Current edition approved June 1, 2008. Published July 2008. Originally approvedin 1981. Last previous edition approved in 2001 as D 4032 94(2001).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact AS
15、TM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Apparatus is commercially available.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, Unite
16、d States.6.1.3.2 Digital gage with maximum reading “hold” featureand capacity of 100 lbf, 50 kgf, or 500 N, with 1000graduations minimum.6.1.4 Actuator, manual or pneumatic.6.2 Specimen Marking Template, (102 by 204 mm) 4.0 by8.0 in.6.3 Stop Watch, for checking stroke speed.7. Sampling7.1 Lot SizeFo
17、r sampling purposes, a lot is defined as asingle shipment of a single style of fabric. A lot may constituteall or part of a single customer order.7.2 Lot SampleAs a lot sample for acceptance testing;take at random the number of rolls of fabric directed in anapplicable material specification or other
18、 agreement betweenthe purchaser and the supplier. Consider rolls of fabric to be theprimary sampling units.NOTE 2An adequate specification or other agreement between thepurchaser and the supplier requires taking into account the variabilitybetween rolls of fabric and between specimens from a swatch
19、from a rollof fabric to provide a sampling plan with a meaningful producers risk,consumers risk, acceptable quality level, and limiting quality level.7.3 Laboratory SampleAs a laboratory sample for accep-tance testing, take a full swatch 1 m (1 yd) long from the endof each roll of fabric in the lot
20、sample, after first discarding aminimum of1m(1yd)offabric from the very outside of therolls.8. Number and Preparation of Test Specimens8.1 Using the specimen marking template specified in 6.2,mark and cut five test specimens from staggered areas of eachswatch in the laboratory sample. The short side
21、 of the specimenmust be parallel to the machine (length) direction of the fabric.Cut no specimens closer to the selvage than one tenth of thefabric width. Lay each specimen face down and fold thespecimen once to form a square 4 by 4 in. (102 by 102 mm).After folding, use the template and hand pressu
22、re to flatten thecrease. Handling of specimens must be kept to a minimum andto the edges to avoid affecting stiffness properties.NOTE 3When otherwise agreed upon, as when specified in anapplicable material specification, the purchaser and the seller may changethe number of test specimens per swatch
23、from the laboratory sample.NOTE 4Fabrics may also be tested face-to-face when the technicalback is used for the outer surface or when there are significant differencesFIG. 1 King Manual Operated Dial ModelD4032082in face and back surface properties. In reporting, indicate that the fabricwas tested f
24、ace-to-face.9. Conditioning9.1 Bring the specimens to moisture equilibrium, as directedin Practice D 1776.10. Procedure10.1 Test the adequately conditioned specimens in thestandard atmosphere for testing textiles which is 21 6 1C(706 2F) and 65 6 2 % relative humidity.10.2 Set the tester on a flat s
25、urface with dial at eye level.FIG. 2 King Air Operated Digital ModelFIG. 3 Platform and PlungerD403208310.3 Select a gage with a capacity in which results will fallwithin 15 to 100 % of dial gage force or 1.5 to 100 % of digitalgage force.10.4 Check tester plunger speed control for full strokelength
26、.10.4.1 Pneumatic ActuatorSet the air pressure control tothe actuator at 324 kPa (47 psi). Using a stop-watch, adjust thepneumatics to provide plunger speed of 1.7 6 0.15 s under noload conditions.10.4.2 Manual ActuatorUsing a stop-watch, establish andconfirm a plunger speed of 1.7 6 0.3 s.NOTE 5The
27、 use of the pneumatic actuated tester gives a morecontrolled result than the manual actuated tester which is subject tooperator variances in the speed at which the plunger is operated (see Table1 and Table 2).10.5 Center a double-ply specimen on the orifice platformbelow the plunger.NOTE 6If 3.2 mm
28、(18 in.) clearance under plunger prevents ease ofentry of specimen due to fabric thickness, the clearance may be increasedto 6.3 mm (14 in.) maximum. In reporting, the results should indicate theplunger clearance, if not standard.10.6 Check the gage zero and adjust, if necessary.10.7 Set the maximum
29、 force reading switch.10.8 Actuate the plunger for the full stroke length. Avoidtouching the specimen during testing.10.9 Record maximum force reading to nearest gage gradu-ation.10.10 Continue as directed in 10.5-10.9, until all specimenshave been tested.11. Calculation11.1 Average the individual s
30、pecimen readings and round tothe nearest gage increment.12. Report12.1 State that the specimens were tested as directed in TestMethod D 4032. Describe the material or product sampled, andthe method of sampling used.12.2 Report the following information:12.2.1 Average force in gage units.12.2.2 Numbe
31、r of specimens tested.12.2.3 Actuator type.12.2.4 Gage type and capacity.12.2.5 How fabric was folded, if not standard (back-to-back).12.2.6 Plunger clearance, if not standard 3.2 mm (18 in.).13. Precision and Bias13.1 Interlaboratory Test DataAn interlaboratory test wasconducted in 1979 in which 29
32、 laboratories each tested 5specimens from 3 different fabrics. Eleven laboratories usedpneumatic actuated testers and 18 laboratories used manual.The first fabric was a 153 g/m2(412 oz/yd2) “pocketing,” 65 %polyester and 35 % cotton. The second was a 339 g/m2(10oz/yd2) broken twill, 50 % polyester a
33、nd 50 % cotton. Thethird was a 492 g/m2(1412 oz/yd2) 100 % cotton denim. Allspecimens were cut at one laboratory from the three fabricsamples. Each laboratory had one operator test each material.The critical differences for stiffness based on all laboratoriesare as specified in Table 2. The critical
34、 differences for stiffnesscomparing pneumatic versus manual actuated testers are speci-fied in Table 3.13.2 PrecisionFor the critical differences reported in 13.1,two averages of observed values should be considered signifi-cantly different at the 95 % probability level if the differenceequals or ex
35、ceeds the critical differences listed in Table 2 andTable 3.13.3 BiasThe procedure in Test Method ASTM D 4032has no bias because the value of stiffness of fabric by thecircular bend procedure is defined in terms of this test method.14. Keywords14.1 fabric; stiffnessTABLE 1 Number of Fabric RollsIn L
36、ot In Lot Sample1to10 111 to 20 221 to 30 331 to 40 441 or more 5D4032084ASTM 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 expressly advised that determination of the validity o
37、f 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 responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments a
38、re invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not re
39、ceived 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, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies)
40、 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).TABLE 2 Stiffness Critical Differences (Summary of all Laboratories and Tester Models) (95 % Confidence Limi
41、ts)Fabric TypeNumber ofObserva-tions in EachAverageAverage Stiffness, N(lbf)Critical Differences, N (lbf)Within-Labo-ratory Preci-sionBetween Labo-ratory Preci-sion153 g/m2(412 oz/yd2) pocketing 3 6.2 (1.4) 5.3 (1.2) 7.6 (1.7)5 6.2 (1.4) 4.4 (1.0) 7.1 (1.6)339 g/m2(10 oz/yd2) twill 3 25.4 (5.7) 10.2
42、 (2.3) 22.7 (5.1)5 24.9 (5.6) 10.2 (2.3) 21.4 (4.8)492 g/m2(1412 oz/yd2) denim 3 69.4 (15.6) 27.1 (6.1) 28.9 (6.5)5 68.9 (15.5) 27.6 (6.2) 28.5 (6.4)TABLE 3 Stiffness Critical Differences (Air Tester versus Manual Tester) (95 % Confidence Limits)Fabric TypeNumber ofObservationsin eachAverageAverage
43、Stiffness, N (lbf) Critical Differences, N (lbf)Air ManualWithin-LaboratoryPrecisionBetween-LaboratoryPrecisionAir Manual Air Manual153 g/m2(412 oz yd2) 3 6.2 (1.4) 6.7 (1.5) 53 (1.2) 4.9 (1.1) 2.7 (0.6) 9.3 (2.1)pocketing 5 5.8 (1.3) 6.7 (1.5) 4.4 (1.0) 4.9 (1.1) 2.7 (0.6) 8.9 (2.0)339 g/m2(10 oz/y
44、d2) twill 3 21.4 (4.8) 27.6 (6.2) 9.3 (2.1) 10.7 (2.4) 11.6 (2.6) 25.4 (5.7)5 21.4 (4.8) 26.7 (6.0) 8.0 (1.8) 10.7 (2.4) 10.2 (2.3) 24.5 (5.5)492 g/m21412 oz/yd23 66.3 (14.9) 71.2 (16.0) 24.0 (5.4) 28.9 (6.5) 26.2 (5.9) 30.2 (6.8)denim 5 67.2 (15.1) 69.8 (15.7) 27.1 (6.1) 27.6 (6.2) 21.8 (4.9) 25.8 (5.8)D4032085
