1、Designation: B916 01 (Reapproved 2017)Standard 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.INTRODUCTIONThe purpose of this test is to provide a standardized procedure to determine and rate the impactadhesion of porcela
3、in 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 the deformation parameters for testingadherence of porcelain enamel to sheet metal;
4、 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 in. or from 1.214 to 0.654 mm).1.3 The values stated in inch-pound units are to
5、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 thesafety concerns, if any, associated with its use. It is theresponsibility of t
6、he user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decisi
7、on on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Significance and Use2.1 The measurement of adherence in porcelain enamelsystems, such as ground coat, ground coat/cover coa
8、t, 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 product.3. Apparatus3.1 Drop Weight Deformation Device2, see
9、 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 concomi-cant damage to the coating is largely influenced by the
10、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. (12.7 mm) diameter hemispherical indenter, 0.75 in.(19.1 mm)
11、 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 Standards, see 7.1.4. Test Specimens4.1 The test specimens shall
12、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 During the procedure in 6.1, fine enameled chips may berelease
13、d with some force from the steel surface; therefore, it is1This 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 Ma
14、y 1, 2017. Published May 2017. Originallyapproved in 2001. Last previous edition approved in 2013 as B916 07(2013)1.DOI: 10.1520/B0916-01R17.2A drop weight device that has been found suitable is available from PacificScientific Co., Gardner/Neotech Instrument Div., 2431 Linden Lane, Silver Spring,MD
15、 20910.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment o
16、f International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1recommended that personnel in the immediate vicinity of thetest wear safety goggles.6. Procedure6.1 Specimen DeformationThe hammer weight of thesuggested drop wei
17、ght device is 5 lb (2268 g), which requiresa 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 this range, but not 5 lb, calculate thedrop dista
18、nce 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 centers and average and treat the measurements onth
19、em 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 is provided with aspring to limit the indenter
20、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 adherence obtained is judged by theamount of glass
21、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 adherencevery little glass adhering, less than
22、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 particles adhering in at least 70 to80 % of the imp
23、act 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, firing, and metal preparation, in cases ofdispute
24、d results, a direct comparison should be made betweenFIG. 1 Drawing of Suitable Drop Weight DeviceB916 01 (2017)2the 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
25、 this test method is beingestablished.10. Keywords10.1 adherence; porcelain enamel coatings; sheet metalFIG. 2 Drop Weight Adherence TesterB916 01 (2017)3Note: See Section 7 for guide to numbers.FIG. 3 Two Coat-One Fire Bond ClassificationB916 01 (2017)4ASTM International takes no position respectin
26、g 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, are entirely their own responsibility.This standa
27、rd 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 standardsand should be addressed to ASTM Internationa
28、l 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 Committee on Standards, at the address shown below.Th
29、is 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 aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax)
30、, 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 Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ See Section 7 for guide to numbers.FIG. 4 One Coat-Ground Coat Bond ClassificationB916 01 (2017)5
