ASTM_C_1862_-_17.pdf

Designation:C186217Standard Test Method for theNominal Joint Strength of End-Plug Joints in AdvancedCeramic Tubes at Ambient and Elevated Temperatures1This standard is issued under the fixed designation C1862;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 the determination of the push-out force,nominal joint strength,and nominal burst pressure ofbonded ceramic end-plugs in advanced ceramic cylindricaltubes(monolithic and composite)at ambient and elevatedtemperatures(see 4.2).The test method is broad in scope andend-plugs may have a variety of different configurations,jointtypes,and geometries.It is expected that the most commontype of joints tested are adhesively bonded end-plugs that useorganic adhesives,metals,glass sealants,and ceramic adhe-sives(sintered powders,sol-gel,polymer-derived ceramics)asthe bonding material between the end-plug and the tube.Thistest method describes the test capabilities and limitations,thetest apparatus,test specimen geometries and preparationmethods,test procedures(modes,rates,mounting,alignment,testing methods,data collection,and fracture analysis),calcu-lation methods,and reporting procedures.1.2 In this end-plug push-out(EPPO)test method,testspecimens are prepared by bonding a fitted ceramic plug intoone end of a ceramic tube.The test specimen tube is securedinto a gripping fixture and test apparatus,and an axialcompressive force is applied to the interior face of the plug topush it out of the tube.(See 4.2.)The axial force required tofracture(or permanently deform)the joined test specimen ismeasured and used to calculate a nominal joint strength and anominal burst pressure.Tests are performed at ambient orelevated temperatures,or both,based on the temperaturecapabilities of the test furnace and the test apparatus.1.3 This test method is applicable to end-plug test speci-mens with a wide range of configurations and sizes.The testmethod does not define a standardized test specimen geometry,because the purpose of the test is to determine the nominal jointstrength and nominal burst pressure of an application-specificplug-tube design.The test specimen should be similar in sizeand configuration with the intended application and productdesign.1.4 Calculations in this test method include a nominal jointstrength which is specific to the adhesives,adherends,configuration,size,and geometry of the test specimen.Thenominal joint strength has value as a comparative test fordifferent adhesives and plug configurations in the intendedapplication geometry.When using nominal joint strength forcomparison purposes,only values obtained using identicalgeometries should be compared due to potential differences ininduced stress states(shear versus tensile versus mixed mode).The joint strength calculated in this test may differ widely fromthe true shear or tensile strength(or both)of the adhesive dueto mixed-mode stress states and stress concentration effects.(True adhesive shear and tensile strengths are material proper-ties independent of the joint geometry.)1.5 In this test,a longitudinal failure stress is being calcu-lated and reported.This longitudinal failure stress acts as anengineering corollary to the burst pressure value measuredfrom a hydrostatic pressure test,which is a more difficult andcomplex test procedure.Thus this longitudinal failure stress isrecorded as a nominal burst pressure.As a general rule,theabsolute magnitude of the nominal burst pressure measured inthis EPPO test is different than the absolute magnitude of aburst pressure from a hydrostatic burst pressure test,becausethe EPPO test does not induce the hoop stresses commonlyobserved in a hydrostatic pressure test.1.6 The use of this test method at elevated temperatures islimited by the temperature capabilities of the loading fixtures,the gripping method(adhesive,mechanical clamping,etc.),andthe furnace temperature limitations.1.7 Values expressed in this test method are in accordancewith the International System of Units(SI)and IEEE/ASTM SI10.1.8 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.1.9 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for the1This test method is under the jurisdiction of ASTM Committee C28 onAdvanced Ceramics and is the direct responsibility of Subcommittee C28.01 onMechanical Properties and Performance.Current edition approved July 1,2017.Published July 2017.Originally approvedin