1、Designation: D 2134 93 (Reapproved 2007)Standard Test Method forDetermining the Hardness of Organic Coatings with aSward-Type Hardness Rocker1This standard is issued under the fixed designation D 2134; the number immediately following the designation indicates the year oforiginal adoption or, in the
2、 case of 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 relativedegree of surface hardness of
3、 organic coatings using a specificapparatus widely used in the coatings industry.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 This test method does not purport to address all of thesafety problems, if any, associated
4、 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. Referenced Documents2.1 ASTM Standards:2D 823 Practices for Producing Films of Uniform Thicknessof Pain
5、t, Varnish, and Related Products on Test PanelsD 1005 Test Method for Measurement of Dry-Film Thick-ness of Organic Coatings Using MicrometersD 1186 Test Methods for Nondestructive Measurement ofDry Film Thickness of Nonmagnetic Coatings Applied toa Ferrous Base3D 1400 Test Method for Nondestructive
6、 Measurement ofDry Film Thickness of Nonconductive CoatingsApplied toa Nonferrous Metal Base3D 3924 Specification for Environment for Conditioning andTesting Paint, Varnish, Lacquer, and Related MaterialsD 4138 Practices for Measurement of Dry Film Thicknessof Protective Coating Systems by Destructi
7、ve, Cross-Sectioning Means3. Significance and Use3.1 Sward-type hardness rocker instruments have been usedby the coatings industry for more than a half a century as anondestructive test instrument to measure cure and ultimatesurface hardness of organic coatings (see Refs. (1) through(11).4An accepte
8、d standard test method for the use of such aninstrument is long overdue.3.2 In previous task group work designed to establish anASTM method for measuring hardness of organic coatingswith Sward-type hardness rocker instruments, round-robin testresults continually showed poor interlaboratory reproduci
9、bility.This lack of interlaboratory agreement could have resultedfrom dimensional variations among instruments, with thecontact rocker rings as the most likely offender in that regard.There are several producers of Sward-type hardness rockersmaking instruments that differ among themselves in net wei
10、ghtand ring radius. Some of them exceed the measurements andnet weight called for in this test method.3.3 This test method, however, is useful within laboratoriesto quickly screen and measure the surface hardness of candi-date coatings.4. Apparatus4.1 Hardness TesterThe hardness tester shall consist
11、 oftwo flat, chromium-plated bronze rings with uniformly roundoutside edges. These rings are separated and held in positionwith a weighted lower member and three horizontal light-weight spacer bars with the topmost one supporting a weightadjustable in height. A rack across the center section support
12、stwo bubble tube-type levels that are used to measure theamplitude of the oscillations of the hardness tester. The rate ofchange in amplitude is used as a measure of hardness orsoftness of the test surface. The hardness tester shall meet thefollowing characteristics:Weight 100 6 10 gDiameter 10 6 0.
13、025 cm (4.000 6 0.010 in.)Width betweenrings2.5 6 0.0125 cm (1.000 6 0.005 in.)Period 50 swings on glass plate in 60.0 6 0.5 sCalibration Decrease in amplitude of 6 taken between ap-proximately 22 and 16 from the vertical, after50 swings on glass1This test method is under the jurisdiction of ASTM Co
14、mmittee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.23 on Physical Properties of Applied Paint Films.Current edition approved Nov. 1, 2007. Published November 2007. Originallyapproved in 1962. Last previous edition approved in 200
15、1 as D 2134 93 (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 information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.4Boldface numbers in parenth
16、eses refer to the list of references at the end of thistest method.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.The hardness tester should be equipped with a clear cover toprotect it from air currents during operation.Asuitable te
17、ster isillustrated in Fig. 1.4.2 Glass PlatesGlass panels approximately 15 cm2(6in.2) and a minimum of 2 mm (78 mils) thick are required.Preferably these should be plate glass; however, carefullyinspected smooth window glass may be substituted.5. Test Specimen5.1 The substrate shall be at least a 50
18、 by 100 by 0.25-mm(2 by 4 by 0.01-in.) smooth piece.5.2 The organic coating specimen shall be a thin film on thesubstrate with a dry thickness of 25 to 50 m (1 to 2 mils).Other dry film thicknesses can be used if agreed upon betweenthe purchaser and the seller. It is very important that the dryfilm
19、thickness is uniform.5.3 The organic coating shall be air dried or heat cured, orboth, using recommended conditions dependent upon the typeof organic coating. Only coatings visually free of holes, craters,orange peel, dust specks, or other surface irregularities shall beused for this test.6. Calibra
20、tion of Hardness Tester6.1 Calibrate the hardness tester on plate glass placed on aleveling table. After the tester is leveled, start oscillation of thetester so that the bubble in the left-hand tube slightly overlapsthe mark. Place the cover in position and start the count(beginning with zero) when
21、 the bubble in the left-hand tubejust fails to reach the mark. Stop the count when the bubble inthe right-hand tube just fails to reach the mark.6.2 The hardness tester shall make 50 6 1 completeoscillations in 60 6 0.5 s. If the number of swings is not 50,adjust the angle of the left-hand bubble tu
22、be to give the correctvalue. The time for 50 swings can be changed by adjustmentsin the position of the weight on the vertical screw.7. Conditioning7.1 ConditioningCondition the test specimens at 23 62C (73.5 6 3.5F) and 50 6 5 % relative humidity for not lessthan 24 h prior to test in accordance wi
23、th Specification D 3924,for those tests where conditioning is required. In cases ofdisagreement, the tolerances shall be 61C (61.8F) and62 % relative humidity.7.2 Test ConditionsConduct tests in the standard labora-tory atmosphere of 23 6 2C (73.5 6 3.5F) and 50 6 5%relative humidity, unless otherwi
24、se specified in the test meth-ods or in Specification D 3924. In cases of disagreement, thetolerances shall be 61C (61.8F) and 62 % relative humid-ity.8. Procedure8.1 Prepare three panels of the organic coating to be testedin accordance with one of the practices described in PracticesD 823. Prior to
25、 testing, condition the panels for 7 days at theconditions specified in Section 7.8.2 Measure the dry film thickness of the organic coatingusing Test Methods D 1005, D 1186, D 1400, or PracticesD 4138.8.3 Determine the initial hardness of the coated panel induplicate, using the procedure in Section
26、6, measuring parallelto the long direction of the coating. The number of completeoscillations multiplied by 2 gives the hardness value.NOTE 1The rings of the hardness tester should be cleaned after eachmeasurement with acetone or other suitable solvent and polished with adry, lint-free cloth.NOTE 2W
27、ith clear organic coatings, inspect the panel from the backside to determine if uniform contact has been made.9. Report9.1 The report shall include the following:9.1.1 Name of rocker producer,9.1.2 Identification of the substrate material,9.1.3 Identification of the organic coating,9.1.4 Method of c
28、oating application,9.1.5 Dry film thickness of organic coating,9.1.6 Conditions used for curing test film, and9.1.7 Mean average of the four readings.10. Precision and Bias10.1 PrecisionThe precision of this test method is beingdetermined.10.2 BiasThis test method has no bias because the valueof har
29、dness is defined only in terms of this test method.11. Keywords11.1 hardness; hardness testsSward hardness; surfacehardnessFIG. 1 Rocker Hardness TesterD 2134 93 (2007)2REFERENCES(1) Bosco, P. J., “The Calibration of the Sward Rocker,” Offcial Digest,Federation of Paint and Varnish Production Clubs,
30、 Vol 26, November1954, pp. 10301038.(2) Baker, D. J., Elleman, A. J., and McKelvie, A. N., “A Theoretical andStatistical Study of Sward Hardness Determinations of Paint Films,”Offcial Digest, Federation of Paint and Varnish Production Clubs, Vol22, December 1950, pp. 10481065.(3) Case, R. A., “The S
31、ward Rocker for Measuring the Modulus ofElasticity of Paint Films,” Journal of Paint Technology, Vol 38, No.496, May 1966, pp. 281284.(4) Gardner, H. A., and Sward, G. G., “Physical and Chemical Examina-tion of Paints, Varnishes, Lacquers, and Colors,” 12th Edition, GardnerLaboratory, Inc., Bethesda
32、, Md. 20034, 1962, pp. 138139.(5) Gardner, H. A., and Sward, G. G., “Physical and Chemical Examina-tion of Paints, Varnishes, Lacquers, and Colors,” ASTM STP 500, 13thed., ASTM, Philadelphia, 1972, pp. 286288.(6) Moore, D. T., “Precision of the Sward Hardness Rocker,” Paint, Oil,and Chemical Review,
33、 Vol 113, No. 21, 1950, p. 41.(7) Pierce, P. E., Holsworth, R. M., and Boerio, F. J., “An Analysis of theSward Rocker Hardness Test,” Journal of Paint Technology, Vol 39,No. 513, October 1967, pp. 593605.(8) Scofield, F., “The Rocker Value and Drying Time of Soft Films,”Scientific Section Circular,
34、National Paint, Varnish, and LacquerAssociation, No. 511, 1936. pp. 225227.(9) Sward, G. G., “A New Apparatus for Testing the Hardness ofSurfaces,” Scientific Section Circular, National Paint, Varnish, andLacquer Association, No. 409, 1932, pp. 120127.(10) Sward, G. G., “Surface Testing Apparatus,”
35、U.S. Patent 1 935 752,November 21, 1933.(11) Sward, G. G., “An Improved Hardness Rocker,” Scientific SectionCircular, National Paint, Varnish, and Lacquer Association, No. 510,1936, pp. 223224.ASTM International takes no position respecting the validity of any patent rights asserted in connection wi
36、th 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 responsible tech
37、nical 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 considerat
38、ion 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, 100 Barr Ha
39、rbor 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 2134 93 (2007)3
