1、Designation: D 3363 05Standard Test Method forFilm Hardness by Pencil Test1This standard is issued under the fixed designation D 3363; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parenthes
2、es indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This test method covers a procedure for rapid, inexpen-sive determinati
3、on of the film hardness of an organic coatingon a substrate in terms of drawing leads or pencil leads ofknown hardness.1.2 This test method is similar in content (but not techni-cally equivalent) to ISO 15184.1.3 The values stated in SI units are to be regarded as thestandard. The values given in pa
4、rentheses are for informationonly.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 limita
5、tions prior to use.2. Referenced Documents2.1 Other Standards:ISO 15184, Determination of film hardness by pencil test.23. Summary of Test Method3.1 A coated panel is placed on a firm horizontal surface.The pencil is held firmly against the film at a 45 angle (pointaway from the operator) and pushed
6、 away from the operator ina 6.5-mm (14-in.) stroke. The process is started with the hardestpencil and continued down the scale of hardness to either oftwo end points: one, the pencil that will not cut into or gougethe film (pencil hardness), or two, the pencil that will notscratch the film (scratch
7、hardness).4. Significance and Use4.1 Pencil hardness measurements have been used by thecoatings industry for many years to determine the hardness ofclear and pigmented organic coating films. This test methodhas also been used to determine the cure of these coatings,especially when forced dried using
8、 heat.4.2 This test method is especially useful in developmentalwork and in production control testing in a single laboratory. Itshould be recognized that the results obtained may varybetween different laboratories when different pencils as well aspanels are used. Every effort should be made to stan
9、dardize thehardness of the lead used and the technique followed.4.3 If this test method is used as a basis for purchaseagreement, maximum precision will be achieved if a given setof referee pencils be agreed upon between the purchaser andthe seller.5. Apparatus5.1 A set of calibrated drawing leads (
10、preferred) or equiva-lent calibrated wood pencils meeting the following scale ofhardness:6B25B24B23B22B2B2HB2F2H22H23H24H25H26HSofter Harder(1)The difference between two adjacent leads shall be consid-ered one unit of hardness.5.2 Mechanical Lead Holder, for drawing leads if used.5.3 Mechanical Shar
11、pener, draftsman-type, is helpful fortrimming wood pencils if used.5.4 Abrasive Paper, grit No. 400.6. Test Specimens and Conditions6.1 Apply the surface coating by appropriate means to asmooth rigid substrate and cure properly, or use representativepanels cut from coated stock. The panels used, the
12、 curingconditions, and the age of the coating prior to the test shall bewithin the limits agreed upon between the purchaser and theseller.6.2 The film thickness of the coating shall be as specified oras agreed upon between the purchaser and the seller.6.3 Conduct the test at 23 6 2C (73.5 6 3.5F) an
13、d 50 65 % relative humidity.7. Procedure7.1 For wood pencils, remove approximately 5 to 6 mm (316to14 in.) of wood from the point of each pencil using adraftsman-type mechanical sharpener, being careful to leave anundisturbed, unmarked, smooth cylinder of lead. Holding thepencil holder (when using d
14、rawing leads) at an angle of 90 to1This method is under the jurisdiction of ASTM Committee D01 on Paint andRelated Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.23 on Physical Properties of Applied Paint Films.Current edition approved Jan. 1, 2005. Publish
15、ed February 2005. Originallyapproved in 1974. Last previous edition D approved in 2000 as D 3363 00.2Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM Internation
16、al, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Copyright by ASTM Intl (all rights reserved); Sun Sep 28 02:17:32 EDT 2008Downloaded/printed byGuo Dehua (CNIS) pursuant to License Agreement. No further reproductions authorized.the abrasive paper, rub the lead
17、against the paper maintainingan exact angle of 90 to the abrasive paper until a flat, smoothand circular cross section is obtained, free of chips or nicks inthe edge of the cross section. For wood pencils, see Fig. 1 foran illustration. For mechanical pencil holders with drawingleads, see Fig. 2 as
18、the illustration. The desired edge may beobtained by cementing the abrasive paper to a flat motor-drivendisk. By supporting the pencil at 90 to the rotating disk auniform flat lead end may be obtained more reproducibly.7.2 For wood pencils, remove approximately 5 to 6 mm (316to14 in.) of wood from t
19、he point of each pencil using adraftsman-type mechanical sharpener, being careful to leave anundisturbed, unmarked, smooth cylinder of lead. Holding thepencil holder (when using drawing leads) at an angle of 90 tothe abrasive paper, rub the lead against the paper maintainingan exact angle of 90 to t
20、he abrasive paper until a flat, smoothand circular cross section is obtained, free of chips or nicks inthe edge of the cross section. The desired edge may be obtainedby cementing the abrasive paper to a flat motor-driven disk. Bysupporting the pencil at 90 to the rotating disk a uniform flatlead end
21、 may be obtained more reproducibly.7.3 Place the coated panel on a level, firm, horizontalsurface. Starting with the hardest lead, hold the pencil or leadholder firmly with the lead against the film at a 45 angle (pointaway from the operator) and push away from the operator.Exert sufficient uniform
22、pressure downward and forward eitherto cut or scratch the film or to crumble the edge of the lead. Itis suggested that the length of the stroke be 6.5 mm (14 in.).7.4 Repeat the process down the hardness scale until apencil is found that will not cut through the film to the substrate(either metal or
23、 a previous coat) for a distance of at least 3 mm(18 in.) (see 8.1.1).NOTE 1The operator must watch closely for cutting into or scratchingthe film. Some finishes contain compounds that may tend to lubricate thefilm. Checks should be made by close visual inspection and by fingernailfeel.NOTE 2In cond
24、ucting the test, if the sharp edge of the lead is slightlychipped or crumbled, the lead must be resharpened.7.5 Continue the process until a pencil is found that willneither cut through nor scratch the surface of the film. Anydefacement of the film other than a cut (gouge) is considered ascratch. Re
25、cord each end point (if applicable) for gouge andscratch hardness (see 8.1).NOTE 3With some films, the two end points will be identical.7.6 Make a minimum of two determinations for gougehardness (7.4) and scratch hardness (7.5) for each pencil orlead.8. Report8.1 Report the following information:8.1
26、.1 The two end points as follows:8.1.1.1 Gouge HardnessThe hardest pencil that will leavethe film uncut for a stroke length of at least 3 mm (18 in.).8.1.1.2 Scratch HardnessThe hardest pencil that will notrupture or scratch the film.8.1.2 The make and grade of lead or pencil used, and8.1.3 Any devi
27、ation from standard conditions, includingroughness in the finish.9. Precision and Bias9.1 PrecisionIn an interlaboratory test of this test methodwith three different films on panels, ten laboratories andoperators, and repeated by switching leads and panels betweenlaboratories, the within-laboratory
28、standard deviation wasfound to be 0.52 and the between-laboratory standard deviationwas found to be 0.61. Based on these standard deviations, thefollowing criteria should be used for judging the acceptabilityof results at a 95 % confidence level:9.1.1 RepeatabilityTwo results obtained by two operato
29、rswithin a laboratory using the same pencils and panels should beconsidered suspect if they differ by more than one pencil uniton the scale described in 5.1.9.1.2 ReproducibilityTwo results, each the mean of atleast two determinations, obtained by operators in differentlaboratories using the same pe
30、ncils and panels or differentpencils with the same panels should be considered suspect ifthey differ by more than one pencil unit on the scale describedin 5.1.9.1.3 BiasSince there is no acceptable material suitablefor determining the bias for the procedure in this test methodfor measuring pencil ha
31、rdness, bias cannot be determined.10. Keywords10.1 hardness (scratch); pencil hardnessFIG. 1 View of Wood Pencil after SharpeningFIG. 2 View of Mechanical Holder with Sharpened Drawing LeadD3363052Copyright by ASTM Intl (all rights reserved); Sun Sep 28 02:17:32 EDT 2008Downloaded/printed byGuo Dehu
32、a (CNIS) pursuant to License Agreement. No further reproductions authorized.SUMMARY OF CHANGESCommittee D01 has identified the location of selected changes to this standard since the last issue(D 3363 00) that may impact the use of this standard.(1) Figs. 1 and 2 were added to make it clearer to the
33、 user ofthis standard how the trimmed wood from wood pencil andgeometry of the lead tip should appear.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 expressly advised that de
34、termination 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 technical committee and must be reviewed every five years andif not revised, either reapproved
35、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 consideration at a meeting of theresponsible technical committee, which you may attend. If you feel t
36、hat 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 Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprint
37、s (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).D3363053Copyright by ASTM Intl (all rights reserved); Sun Sep 28 02:17:32 EDT 2008Downloaded/printed byGuo Dehua (CNIS) pursuant to License Agreement. No further reproductions authorized.
