ASTM_C_1674_-_16.pdf

Designation:C167416Standard Test Method forFlexural Strength of Advanced Ceramics with EngineeredPorosity(Honeycomb Cellular Channels)at AmbientTemperatures1This standard is issued under the fixed designation C1674;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.Scope*1.1 This test method covers the determination of the flexuralstrength(modulus of rupture in bending)at ambient conditionsof advanced ceramic structures with 2-dimensional honeycombchannel architectures.1.2 The test method is focused on engineered ceramiccomponents with longitudinal hollow channels,commonlycalled“honeycomb”channels.(See Fig.1.)The componentsgenerally have 30%or more porosity and the cross-sectionaldimensions of the honeycomb channels are on the order of1 mm or greater.Ceramics with these honeycomb structuresare used in a wide range of applications(catalytic conversionsupports(1),2high temperature filters(2,3),combustionburner plates(4),energy absorption and damping(5),etc.).Thehoneycomb ceramics can be made in a range of ceramiccompositionsalumina,cordierite,zirconia,spinel,mullite,silicon carbide,silicon nitride,graphite,and carbon.Thecomponents are produced in a variety of geometries(blocks,plates,cylinders,rods,rings).1.3 The test method describes two test specimen geometriesfor determining the flexural strength(modulus of rupture)for aporous honeycomb ceramic test specimen(see Fig.2):1.3.1 Test Method AA4-point or 3-point bending test withuser-defined specimen geometries,and1.3.2 Test Method BA4-point-14point bending test with adefined rectangular specimen geometry(13 mm 25 mm 116 mm)and a 90 mm outer support span geometry suitable forcordierite and silicon carbide honeycombs with small cellsizes.1.4 The test specimens are stressed to failure and thebreaking force value,specimen and cell dimensions,andloading geometry data are used to calculate a nominal beamstrength,a wall fracture strength,and a honeycomb structurestrength.1.5 Test results are used for material and structuraldevelopment,product characterization,design data,qualitycontrol,and engineering/production specifications.1.6 The test method is meant for ceramic materials that arelinear-elastic to failure in tension.The test method is notapplicable to polymer or metallic porous structures that fail inan elastomeric or an elastic-ductile manner.1.7 The test method is defined for ambient testing tempera-tures.No directions are provided for testing at elevated orcryogenic temperatures.1.8 The values stated in SI units are to be regarded asstandard(IEEE/ASTM SI 10).English units are sparsely usedin this standard for product definitions and tool descriptions,per the cited references and common practice in the USautomotive industry.1.9 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 use.2.Referenced Documents2.1 ASTM Standards:3C373 Test Methods for Determination of Water Absorptionand Associated Properties by Vacuum Method for PressedCeramic Tiles and Glass Tiles and Boil Method forExtruded Ceramic Tiles and Non-tile Fired CeramicWhiteware ProductsC1145 Terminology of Advanced CeramicsC1161 Test Method for Flexural Strength of AdvancedCeramics at Ambient Temperature1This test method is under the jurisdiction of ASTM Committee C28 onAdvanced Ceramics and is the direct responsibility of Subcommittee C28.04 onApplications.Current edition approved Dec.15,2016.Published January 2017.Originallyapproved in 2008.Last previous edition approved in 2011 as C1674 11.DOI:10.1520/C1674-16.2The boldface numbers in parentheses refer to the list of references at the end ofthis standard.3For 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.*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 StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 C1198 Test Method for Dynamic Youngs Modulus,ShearModulus,and Poissons Ratio for Advanced Ceramics bySonic ResonanceC1239 Practice for Reporting Uniaxial Strength Data andEstimating Weibull Distribution Parameters for AdvancedCerami