1、Designation: B916 01 (Reapproved 2013)1Standard Test Method forAdherence of Porcelain Enamel Coatings to Sheet Metal1This standard is issued under the fixed designation B916; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、 of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1NOTEAbstract and ratings in Figures 3 and 4 were added editorially in May 2013.INTRODUCTIONThe purpose of this test is to pro
3、vide a standardized procedure to determine and rate the impactadhesion of porcelain enamels on sheet steel.1. Scope1.1 The scope of this test method is:1.1.1 To determine quantitatively the amount of enamelremaining after the porcelain enamel coating specimen hasbeen deformed;1.1.2 To standardize th
4、e deformation parameters for testingadherence of porcelain enamel to sheet metal; and,1.1.3 To provide a quantitative adherence rating scale forcomparison to reference standards.1.2 This adherence test method is applicable to porcelainenamel coatings on substrates from 18 to 24 gauge (0.0478 to0.025
5、 in. or from 1.214 to 0.654 mm).1.3 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.4 This standard does not purport to address all of
6、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. Significance and Use2.1 The measurement of adherence in porcelain
7、 enamelsystems, such as ground coat, ground coat/cover coat, anddirect-on cover-coat enamels, is an important procedure formonitoring process variables in metal preparation, enamelapplication thickness, steel selection, and enamel selection, aswell as assuring the ultimate quality of the finished pr
8、oduct.3. Apparatus3.1 Drop Weight Deformation Device2, see Figs. 1 and 2.3.2 The drop weight deformation device as shown in Fig. 1shall impart a single impact blow from a hemisphericalindenter to a coated specimen supported over a sharp-edgedbottomless die. The area of the deformation and the concom
9、i-cant damage to the coating is largely influenced by the size ofthe hemispherical indenter; the die opening size and edgesharpness; and, the energy of the blow at impact.3.3 A satisfactory degree of deformation and damage areobtained if the conditions in 3.2 use the following parameters:0.50 in. (1
10、2.7 mm) diameter hemispherical indenter, 0.75 in.(19.1 mm) diameter bottomless die (lower plunger guide inFig. 1) with sharp edge, and 80 in./lb (9.03 J) energy at impact.3.4 Deformation Devices, of other designs may be usedprovided that the parameters in 3.3 are used.3.5 Adherence Reference Standar
11、ds, see 7.1.4. Test Specimens4.1 The test specimens shall be flat enameled panels not lessin size than 4 in.2(101.6 mm2). Larger sizes and shapes may beused provided that a flat surface can be held firmly against andparallel to the lower plunger guide during deformation.5. Safety Precautions5.1 Duri
12、ng the procedure in 6.1, fine enameled chips may bereleased with some force from the steel surface; therefore, it isrecommended that personnel in the immediate vicinity of thetest wear safety goggles.6. Procedure6.1 Specimen DeformationThe hammer weight of thesuggested drop weight device is 5 lb (22
13、68 g), which requires1This test method is under the jurisdiction of ASTM Committee B08 on Metallicand Inorganic Coatings and is the direct responsibility of Subcommittee B08.12 onMaterials for Porcelain Enamel and Ceramic-Metal Systems.Current edition approved March 1, 2007. Published May 2013. Orig
14、inallyapproved in 2001. Last previous edition approved in 2007 as B916 07 (2007).DOI: 10.1520/B0916-01R13E01.2A drop weight device that has been found suitable is available from PacificScientific Co., Gardner/Neotech Instrument Div., 2431 Linden Lane, Silver Spring,MD 20910.Copyright ASTM Internatio
15、nal, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1a 16 in. (406.4 mm) drop distance to yield the specified 80in./lb (9.03 J) energy at impact. The hammer weight of the dropweight device may range from 2 to 8 lb (907 to 3629 g). If thehammer weight is within thi
16、s range, but not 5 lb, calculate thedrop distance to yield 80 in./lbf of energy at impact. The centerof the area to be deformed shall be at least 112 in. (38.1 mm)from the edge of the specimen. If two or more deformations aremade on a single specimen, place them at least 3 in. (76.2 mm)between cente
17、rs and average and treat the measurements onthem as a single measurement. Raise and secure the hammer toobtain the required drop distance. Hold the specimen firmlyagainst and parallel to the top surface of the die with theenameled side up and release the hammer.6.2 The specified drop weight device i
18、s provided with aspring to limit the indenter to a single impact blow against thespecimen. If the device to be used is not designed in this way,use another means or procedure to avoid a restrike of theindenter.6.3 A visual examination of the impact area is then made.Evaluation of the degree of adher
19、ence obtained is judged by theamount of glass retained in the impact area.7. Rating of Adherence7.1 Examine the impacted area and compare to the follow-ing reference standards (see Figs. 3 and 4):0 = No adherenceonly shiny metal showing, and enamel may beflaking off beyond the impact area.1 = Poor a
20、dherencevery little glass adhering, less than 10 %, andonly at the outer edges of the impact area.2 = Fair adherenceglass particles adhering in at least 25 to 30 %of the impact area.3 = Good adherenceglass particles adhering in at least 50 to 60 %of the impact area.4 = Very good adherenceglass parti
21、cles adhering in at least 70 to80 % of the impact area.5 = Excellent adherenceglass particles covering almost all of theimpact areaat least 90 %.7.2 Report adherence rating, estimated to the nearest 0.5.8. Referee Method8.1 Since adherence depends on factors other than theenamel, that is, steel, fir
22、ing, and metal preparation, in cases ofdisputed results, a direct comparison should be made betweenthe test enamel known to have acceptable adherence by coatingone-half of a panel with each of the enamels and comparingresults as in 7.1.9. Precision and Bias9.1 The precision and bias of this test met
23、hod is beingestablished.10. Keywords10.1 adherence; porcelain enamel coatings; sheet metalFIG. 1 Drawing of Suitable Drop Weight DeviceB916 01 (2013)12FIG. 2 Drop Weight Adherence TesterB916 01 (2013)13Note: See Section 7 for guide to numbers.FIG. 3 Two Coat-One Fire Bond ClassificationB916 01 (2013
24、)14ASTM 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 of any such patent rights, and the riskof infringement of such rights,
25、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 are invited either for revision of this standard or for additional stan
26、dardsand 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 received a fair hearing you shouldmake your views known to the ASTM Comm
27、ittee 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) of this standard may be obtained by contacting ASTM at the aboveaddre
28、ss or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).Note: See Section 7 for guide to numbers.FIG. 4 One Coat-Ground Coat Bond ClassificationB916 01 (2013)15
