ASTM D772-1986(2005) Standard Test Method for Evaluating Degree of Flaking (Scaling) of Exterior Paints《外部涂料剂落程度评价的试验方法》.pdf

1、Designation: D 772 86 (Reapproved 2005)Standard Test Method forEvaluating Degree of Flaking (Scaling) of Exterior Paints1This standard is issued under the fixed designation D 772; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the

2、 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This test method covers the

3、 evaluation of the degree offlaking (scaling) of exterior paints by comparison with photo-graphic standards.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 standard does not purport to address all of thesafety conc

4、erns, 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. Referenced Documents2.1 ASTM Standards:2D 1150 Single and Multi-Panel Forms for

5、 Recording Re-sults of Exposure Tests of Paints2.2 Other Standards:Pictorial Standards of Coating Defects Handbook33. Terminology3.1 Definitions of Terms Specific to This Standard:3.2 flaking (scaling), nthat phenomenon manifested inpaint films by the actual detachment of pieces of the film itselfei

6、ther from its substrate or from paint previously applied.3.2.1 DiscussionFlaking (scaling) is generally precededby cracking or checking or blistering, and is the result of lossof adhesion, usually due to stress-strain factors coming intoplay.4. Significance and Use4.1 Flaking (scaling) failure of pa

7、int films can occur in use.This test method provides a means of evaluating the degree offailure by comparing to pictorial standards.5. Type of Flaking (Scaling)5.1 Only one type of flaking (scaling) is recognized, asdefined in Section 3.6. Use of Photographic Reference Standards6.1 The photographic

8、reference standards that are part ofthis test method and are provided in the Pictorial Standards ofCoating Defects Handbook are representative of the degree ofcracking of exterior paint films. Fig. 1 is for illustrationpurposes only and should not be used for evaluation.6.2 The use of the photograph

9、ic reference standards3illus-trated in Fig. 1 requires the following precautions:6.2.1 Care must be taken not to confuse various types offailure that may be present on the same surface.6.2.2 It must be realized that degree of failure will vary overany given area. Therefore, an average portion of the

10、 filmshould be used for comparison. On larger surfaces it isrecommended that ratings be made at several locations and themean and range reported.6.2.3 In technical literature, a distinction is sometimes madebetween flaking and scaling. In most cases, however, flakingand scaling refer to the same phe

11、nomenon. In some instances,the term flaking is used to describe the detachment of pieces offilm less than 6.4 mm (14 in.) in size, and scaling, thedetachment of pieces over14 in. in size. In other instances, theterm flaking is used to describe the detachment of pieces offilm from the immediate under

12、coat (intercoat failure) andscaling the detachment of pieces from the base (completefailure). It should be kept in mind that the flakes may vary1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility

13、 ofSubcommittee D01.25 on Evaluation of Weathering Effects.Current edition approved Sept. 1, 2005. Published December 2005. Originallyapproved in 1944. Last previous edition approved in 2000 as D 772 86 (2000).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Custo

14、mer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Copies of the pictorial photographic reference standards are contained in thepublication Pictorial Standards of Coatings Defects and may be obtained f

15、rom theFederation of Societies for Coatings Technology, 492 Norristown Rd., Blue Bell,PA 19422. The silver halide-gelatin photographs are intended to be the only primaryreference standards for this method. The reproductions of them in this test methodare for the purpose of illustration only.1Copyrig

16、ht ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.FIG. 1 Degrees of Flaking (Scaling)D 772 86 (2005)2widely in size and shape from those illustrated by the referencestandards in Fig. 1, varying from a fraction of an inch to severalinches in si

17、ze.6.2.4 Peeling is frequently due to a moisture condition andwhen this is evident it should be taken into consideration in anyevaluation.FIG. 1 Degrees of Flaking (Scaling) (continued)D 772 86 (2005)36.2.5 For convenience in recording the data obtained, therecords may be kept on forms such as Stand

18、ard D 1150.47. Precision and Bias7.1 No precision or bias statement has been established forthis test method.8. Keywords8.1 evaluations; flaking; reference standards; scalingASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mention

19、edin 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 technical committee and

20、 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 consideration at a meeting of

21、 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 Harbor Drive, PO Box

22、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).4These record sheets may be obtained from the Federation of Societies forCoatings Technology.D 772 86 (2005)4