1、Designation: D5638 05 (Reapproved 2010)An American National StandardStandard Test Method forChemical Resistance of Electrical Insulating Varnishes1This standard is issued under the fixed designation D5638; the number immediately following the designation indicates the year oforiginal adoption or, in
2、 the case of revision, the year 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. Scope1.1 This test method covers the mechanical performance ofinsulating varnishes after exp
3、osure to various chemicals.1.2 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.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
4、 standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. See 7.1.NOTE 1There is no IEC/ISO equivalent.2. Referenced Documents2.1 ASTM Standards:2D2519 Test Method for Bond Strength of Electrical Insu-lating Varnishes by
5、the Helical Coil Test3. Terminology3.1 See Test Method D2519.4. Summary of Test Method4.1 Flexural strength tests are made on varnish-treatedhelical coils to determine the force required to break the coilunder specified conditions both before and after exposure toliquid chemicals.5. Significance and
6、 Use5.1 This test method is useful for the evaluation of insulat-ing varnish performance in chemical exposure.6. Apparatus6.1 Tensile Testing MachineSee Test Method D2519.6.2 Test FixtureSee Test Method D2519.6.3 Chemical ContainersSealable 1000 mL containers ofsuitable material and design for conta
7、ining the chemicals to beused.7. Safety Precautions7.1 It is unsafe to use varnish at temperatures above theflash point without adequate ventilation, especially if thepossibility exists that flames or sparks are present. Storevarnish in sealed containers.8. Test Specimen8.1 Prepare a minimum of five
8、 test specimens for eachchemical solution to be tested and five to determine uncondi-tioned bond strength in accordance with Test Method D2519using a wire mutually agreed upon by supplier and user.9. Procedure9.1 Condition a minimum of five test specimens in eachchemical. Chemicals, test temperature
9、 and conditioning timeare mutually agreed upon by supplier and user.9.2 Test specimens both conditioned and unconditioned asdescribed in Test Method D2519 at standard laboratory condi-tions. Test conditioned specimens within 15 min of removalfrom container to minimize any change in bond strength aft
10、erexposure. Rinse conditioned specimens with water and pat drywhen water soluble chemicals were used for conditioning.Otherwise wipe specimens to remove excess chemical.10. Report10.1 Report the following information:10.1.1 Description of varnish,10.1.2 Identification of wire used,10.1.3 Cure time a
11、nd temperature and number of dips usedto prepare the coils,10.1.4 Average bond strength in newtons (pounds-force) ofunconditioned coils,10.1.5 Average bond strength in newtons (pounds-force) ofconditioned coils,10.1.6 Description of chemical, exposure temperature, andexposure time to which the speci
12、mens were subjected, and10.1.7 Percent retention of bond strength after conditioningper the formula below.1This test method is under the jurisdiction of ASTM Committee D09 onElectrical and Electronic Insulating Materials and is the direct responsibility ofSubcommittee D09.01 on Electrical Insulating
13、 Varnishes, Powders and Encapsulat-ing Compounds.Current edition approved May 1, 2010. Published September 2010. Originallyapproved in 1994. Last previous edition approved in 2005 D563805. DOI:10.1520/D5638-05R10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Cu
14、stomer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Percent Retained Bond Strength5Av
15、erage Bond Strength conditionedAverage Bond Strength unconditioned3 10011. Precision and Bias11.1 PrecisionNo information has been presented toASTM upon which to base a statement of precision. Noactivity has been planned to develop such information.11.2 BiasThis test method has no bias because the v
16、aluefor chemical resistance is determined solely in terms of this testmethod.12. Keywords12.1 bond strength; chemical resistance; helical coils;varnishASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Use
17、rs 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 must be reviewed every
18、 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 theresponsible technic
19、al 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 C700, West Conshohocken
20、, 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/).D5638 05 (2010)2
