ASTM_C_949_-_80_2016.pdf

Designation:C94980(Reapproved 2016)Standard Test Method forPorosity in Vitreous Whitewares by Dye Penetration1This standard is issued under the fixed designation C949;the number immediately following the designation indicates the year oforiginal adoption or,in 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 procedures for detecting pores,cracks,or other voids that may be present in otherwiseimpermeable whiteware ceramics,or as porosity in underfiredware.NOTE1This test method was partially derived from ANSI C29.1.1.2 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 standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use2.Referenced Documents2.1 ASTM Standards:2C242 Terminology of Ceramic Whitewares and RelatedProducts2.2 ANSI Standard:C 29.1 Test Methods for Electrical Power Insulators33.Terminology3.1 Definitions:3.1.1 For definitions of terms used in this test method,referto Terminology C242.4.Summary of Test Method4.1 Randomly selected unglazed fragments of vitreouswhiteware products are immersed in a fuchsine dye solution,atone or more pressures for prescribed times.After drying,thespecimens are broken and inspected for the extent of dyepenetration into the body,or into defects present in the body.5.Significance and Use5.1 This test method provides a means for readily determin-ing if a ceramic is properly fired(matured).Penetration of anyextent may negate the usefulness of the ceramic,or,arbitrarily,some degree of penetration may be acceptable for the use orcommercial quality of the item being tested.6.Apparatus6.1 Vessel,capable of applying and holding a pressure of10 000 psi(68.9 MPa).6.1.1 Fig.1 illustrates a satisfactory device.NOTE2Fig.1 does not represent the only possible design orconfiguration.It is representative of a device that has been successfullyused.6.1.2 Fig.2 illustrates an actual device and typical ex-amples.6.1.3 Fig.3 illustrates an assembled device,includingfixture,under pressure.7.Testing Solution7.1 Use a solution consisting of 1 g of basic fuchsine dyedissolved in 1 L of 50%alcohol.NOTE3The alcohol used should not react with the dye to causefading.8.Preparation of Test Specimens8.1 Use freshly broken fragments,approximately14in.(6 mm)in the smallest dimension,up to34in.(19 mm)in thelargest dimension,of the whiteware ceramic.At least 75%ofthe surface shall be free of glaze or other surface treatment.9.Procedure9.1 Immerse the test specimens in the testing solution withinthe pressure chamber,and9.2 Apply a minimum pressure of 4000 psi(27.6 MPa)fornot less than 5 h,or9.3 Apply a minimum 10 000 psi(68.9 MPa)for not lessthan 2 h,or9.4 Immerse the specimens in the testing solution at atmo-spheric pressure,in an open vessel,for any period of timeappropriate to the needs of the tester.1This test method is under the jurisdiction ofASTM Committee C21 on CeramicWhitewares and Related Productsand is the direct responsibility of SubcommitteeC21.03 on Methods for Whitewares and Environmental Concerns.Current edition approved Nov.1,2016.Published November 2016.Originallyapproved in 1980.Last previous edition approved in 2012 as C949 80(2012).DOI:10.1520/C0949-80R16.2For 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 American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 10.Examination10.1 After following the procedures in 9.2,9.3,or 9.4,dryand break the test specimen for examination.10.2 Porosity is indicated by penetration of the dye into thespecimens to an extent visible to the unaided eye.10.3 Disregard penetration into small fissures formed inpreparing the test specimens.11.Report11.1 Report the following information:11.1.1 Whether penetration occurred and to what depth,11.1.2 Pressure used,and11.1.3 Time under pressure.12.Precision and Bias12.1 This test method is qualitative and is liable to subjec-tive interpretation.Within a given laboratory,agreement shouldbe possible between several operators whether penetrationexceeds in-house acceptance standards.13.Keywords13.1 ceramics;porosity;whitewaresNOTE11 in.=25.4 mm.FIG.1 Typical Pressure Vessel for Dye Penetration TestC949 80(2016)2 FIG.2 Typical Unassembled Pressure Vessel and SamplesFIG.3 A Typical Assembled Pressure VesselC949 80(2016)3 ASTM International takes no position respecting the validity of any patent rights asserted in conne