1、Designation: D4242 07 (Reapproved 2013)Standard Test Method forInclined Plate Flow for Thermosetting Coating Powders1This standard is issued under the fixed designation D4242; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the yea
2、r 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.1. Scope*1.1 This test method specifies a method for determining theflow characteristics of a fused thermosetting coating pow
3、derdown a plane inclined at a set angle to the horizontal. The testgives an indication of the degree of melt flow that may occurduring the curing of the coating powder. This characteristiccontributes to the coherence of the coating, to its surfaceappearance and to the degree of coverage over sharp e
4、dges (seeTest Method D2967), however, it should not be used as the solefactor for judgment. The test acts as a useful method forchecking for batch to batch variation in the behavior of a givencoating powder. Correlation between the results from coatingpowders of differing composition is not to be ex
5、pected. Thismethod is unlikely to yield meaningful results with coatingpowders which have gel times of less than one minute at thetest temperature (see Test Method D4217). Oven drafts, angleof inclination and pellet variations significantly affect resultsmaking inter-lab reproducibility somewhat dif
6、ficult to corre-late.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 concerns, if any, associated with its use. It is theresponsibility of the user of this stan
7、dard to establish appro-priate safety and health practices and to determine theapplicability of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D792 Test Methods for Density and Specific Gravity (Rela-tive Density) of Plastics by DisplacementD2967 Test Method for Corne
8、r Coverage of Powder Coat-ingsD4217 Test Method for Gel Time of Thermosetting CoatingPowderD5965 Test Methods for Specific Gravity of Coating Pow-ders2.2 Other Documents:ISO 8130-2 Coating powdersPart 2: Determination ofdensity by gas comparison pyknometer3ISO 8130-3 Coating powdersPart 3: Determina
9、tion ofdensity by liquid displacement pyknometer3ISO 813011:1997 Coating powdersPart 11: Inclined-plane flow test33. Terminology3.1 Definitions:3.1.1 coating powder, nfinely divided particles of resin,either thermoplastic or thermosetting, generally incorporatingpigments, fillers, and additives and
10、remaining finely dividedduring storage under suitable conditions, which after fusingand possibly curing, give a continuous film.3.1.2 powder coating, ncoatings which are protective ordecorative, or both, formed by the application of a coatingpowder to a substrate and fused in a continuous film by th
11、eapplication of heat or radiant energy.3.1.3 gel time of a coating powder, nthe interval requiredat a given temperature for a coating powder to be transformedfrom a dry solid to a gel-like state.3.1.4 cure time of a coating powder, nthe time required fora thermosetting coating powder to sufficiently
12、 chemicallycrosslink at a given temperature to provide the required coatingproperties.3.1.5 thermosetting, adjdescribing a material that, whenheated per a minimum recommended cure condition, under-goes a chemical reaction and a permanent change to a moredurable state capable of specific properties a
13、s designed forsubstrate protection or decoration, or both.4. Summary of Test Method4.1 The thermosetting coating powder is pressed into apellet of standard size which is allowed to melt and flow downa heated inclined plate. The extent of flow is measured.1This test method is under the jurisdiction o
14、f ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.51 on Powder Coatings.Current edition approved June 1, 2013. Published July 2013. Originally approvedin 1983. Last previous edition approved in 2007 as D4242 07. DOI: 10
15、.1520/D4242-07R13.2For 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.3Available from International Organization
16、for Standardization (ISO), 1 rue deVaremb, Case postale 56, CH-1211, Geneva 20, Switzerland, http:/www.iso.ch.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15. Signific
17、ance and Use5.1 This test method is useful for selecting coating powdersof similar characteristics of melt flow under minimal shear. Itis not recommended as an absolute measurement, but rather asa comparative measurement of samples on the same panelmeasured at the same time.6. Apparatus6.1 Fan-assis
18、ted air circulation oven, capable of maintain-ing the desired temperature to 62C (64F).6.2 Glass plates, of suitable dimensions to undertake thetest. As an alternative, metal plates may be used. However,these will need to be closely defined with respect to theircomposition and surface finish. The pl
19、ates shall be sufficientlyrigid so as not to flex during the text. The details of the glassor metal plates shall be included in the test report.6.3 Plate assembly, of suitable metal and design that fitsinside the oven. The assembly shall be capable of carrying oneor more of the plates (6.2) in a hor
20、izontal position and at anangle of 65 6 1 to the horizontal when moved by a leverprojecting through the side of the oven. Alternatively a fixedplate holder, of suitable metal and design, capable of holdingone or more of the plates at 65 6 1 to the horizontal may beused. If otherwise agreed to, test
21、angles other than 65 may beused and thus reported.6.4 Balance, capable of measuring to 610 mg.6.5 Steel pellet-molding press, together with a knockout rod,capable of making pellets of 12.5 6 0.05 mm (0.5 6 0.002 in.)in diameter and 6.5 6 0.2 mm (0.25 6 0.008 in.) thick.6.6 Steel rule, graduated in m
22、illimeters.7. Sampling7.1 Obtain a representative sample of the coating powder.7.2 Store the sample of coating powder in accordance withthe manufacturers recommendations, after sampling and priorto testing.8. Procedure8.1 Always include a sample of known flow in the test as acontrol. Carry out the d
23、eterminations in duplicate.8.2 Weigh on the balance to an accuracy of 10 mg a mass ofthe product under test equivalent in grams to half of the density(specific gravity) of the coating powder in accordance withTest Methods D792, D5965, ISO 8130-2, or ISO 8130-3. Bymeans of the pellet press, compact t
24、he coating powder into apellet 12.5 6 0.05 mm (0.5 6 0.002 in.) in diameter and 6.5 60.2 mm (0.25 6 0.008 in.) thick and push the pellet out of thepress with the knockout rod. Weigh the pellet to confirm that itsmass is correct to 10 mg. If there is a delay between thecommencement of the test and th
25、e preparation of the pellet,protect it against moisture absorption by storage in a desiccatoror a sealed container.8.3 Unless otherwise agreed, the temperature of the testshall be the recommended curing temperature. In the absenceof this information, a temperature shall be used that providesan adequ
26、ate pill flow for measurement.8.4 If a plate assembly is to be used, place the plate(s) in theplate assembly in a horizontal position. Place the plate assem-bly and plate(s) into the oven set at the test temperature andallow the holder to attain the test temperature. Alternatively, itmay be more con
27、venient to maintain the plate assembly in theoven and carefully load the plate(s) in situ.8.5 At the end of the preheat period turn off the circulationfan and open the door of the oven. Place the pellet(s) towardsthe end of the plate(s) that will be uppermost when tilted. Closethe door of the oven a
28、nd restart the fan. This operation shalltake no longer than 15 s to perform. After a further 15 s sinceclosing the oven door, operate the plate assembly to bring theplate(s) to 65 6 1 to the horizontal. Allow the plate(s) toremain in this position for 15 min. At the end of this periodremove the plat
29、e(s) from the oven and allow to cool to roomtemperature in a horizontal position.8.6 Using the steel rule, measure the total length of theflowed pellet in millimeters. This is most conveniently under-taken with glass plates by viewing from the reverse side andrecording the total length of the flowed
30、 pellet. Record themeasurements to the nearest 0.5 mm.8.7 If a fixed plate holder is to be used, place the holder intothe oven set at the test temperature and allow the holder toattain the test temperature. Metal panels are most commonlyused with a fixed plate holder. Take the metal panel(s) at room
31、temperature and place the prepared pellet(s) towards the end ofthe panel(s) that will be uppermost when positioned in the plateholder. Heat the underside of the end metal panel where thepellet(s) are located until the pellet(s) just stick to the metal.This is conveniently accomplished by resting the
32、 underside ofthe end of the panel on a hot plate and allowing the heat toconduct through the panel and cause the pellet(s) to adhere.This should take no longer than 5 s. Care should be taken toavoid excessive heat which will distort the shape of thepellet(s). Immediately (within 15 s) place the pane
33、l(s) onto thefixed plate holder already at test temperature in the oven.Allowthe panel(s) to remain on the fixed plate holder at 65 6 1 tothe horizontal for 15 min. At the end of this period remove thepanel(s) from the oven and allow to cool to room temperaturein a horizontal position.8.8 Using the
34、steel rule, measure the total length of theflowed pellet in millimeters. Record the measurement to thenearest 0.5 mm.9. Calculation9.1 Whatever method of plate or panel support is used, if theduplicate results differ by less than 5 % of the lower figure,calculate and report the arithmetic mean to th
35、e nearest 0.5 mm.If the difference between the two results exceeds 5 %, repeatthe procedure described in Section 8.10. Report10.1 The test report should contain at least the followinginformation:10.1.1 All details necessary to identify the product tested,10.1.2 A reference to this standard,10.1.3 Th
36、e test temperature,D4242 07 (2013)210.1.4 The weight of pellet,10.1.5 The results of the test (individual values and meanvalue),10.1.6 Plate composition and dimensions and if a metalpanel was used, a description of its surface finish,10.1.7 Method of plate support inside oven,10.1.8 Any deviation fr
37、om the test method specified, and10.1.9 The date of the test.11. Precision and Bias11.1 PrecisionIt is not possible to specify the precision ofthe procedure in Test Method D4242 for measuring inclinedplate flow because adequate data has not been established. Noactivity is planned to develop such dat
38、a.11.2 BiasThis test method has no bias because the valuefor plate flow is defined solely in terms of this test method.12. Keywords12.1 coating powder; pellet flow; pill flow; plate flow;powder coating; thermosettingSUMMARY OF CHANGESCommittee D01 has identified the location of selected changes to t
39、his standard since the last issue (D4242 - 02)that may impact the use of this standard. (Approved June 1, 2007.)(1) Title of Test Method D2967 corrected to “Test Method forCorner Coverage of Powder Coatings” in 2.1.(2) Added specific gravity for clarification in Procedure 8.2.ASTM International take
40、s 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, are entirely their own res
41、ponsibility.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 standardsand should be address
42、ed 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 Committee on Standards, at the
43、 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 aboveaddress 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/).D4242 07 (2013)3
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