ASTM_C_1548_-_02_2012.pdf

Designation:C154802(Reapproved 2012)Standard Test Method forDynamic Youngs Modulus,Shear Modulus,and PoissonsRatio of Refractory Materials by Impulse Excitation ofVibration1This standard is issued under the fixed designation C1548;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 measurement of the funda-mental resonant frequencies for the purpose of calculating thedynamic Youngs modulus,the dynamic shear modulus(alsoknown as the modulus of rigidity),and the dynamic Poissonsratio of refractory materials at ambient temperatures.Speci-mens of these materials possess specific mechanical resonantfrequencies,which are determined by the elastic modulus,mass,and geometry of the test specimen.Therefore,thedynamic elastic properties can be computed if the geometry,mass,and mechanical resonant frequencies of a suitablespecimen can be measured.The dynamic Youngs modulus isdetermined using the resonant frequency in the flexural modeof vibration and the dynamic shear modulus is determinedusing the resonant frequency in the torsional mode of vibration.Poissons ratio is computed from the dynamic Youngs modu-lus and the dynamic shear modulus.1.2 Although not specifically described herein,this methodcan also be performed at high temperatures with suitableequipment modifications and appropriate modifications to thecalculations to compensate for thermal expansion.1.3 The values are stated in SI units and are to be regardedas the standard.1.4 This standard may involve hazardous materials,operations,and equipment.This standard does not purport toaddress all of the safety concerns,if any,associated with itsuse.It is the responsibility of the user of this standard toestablish appropriate safety and health practices and deter-mine the applicability of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2C71 Terminology Relating to RefractoriesC215 TestMethodforFundamentalTransverse,Longitudinal,and Torsional Resonant Frequencies ofConcrete SpecimensC885 Test Method for Youngs Modulus of RefractoryShapes by Sonic ResonanceC1259 Test Method for Dynamic Youngs Modulus,ShearModulus,and Poissons Ratio for Advanced Ceramics byImpulse Excitation of Vibration3.Summary of Test Method3.1 The fundamental resonant frequencies are determinedby measuring the resonant frequency of specimens struck oncemechanically with an impacting tool.Frequencies are mea-sured with a transducer held lightly against the specimen usinga signal analyzer circuit.Impulse and transducer locations areselected to induce and measure one of two different modes ofvibration.The appropriate resonant frequencies,dimensions,and mass of each specimen may be used to calculate dynamicYoungs modulus,dynamic shear modulus,and dynamic Pois-sons ratio.4.Significance and Use4.1 This test method is non-destructive and is commonlyused for material characterization and development,designdata generation,and quality control purposes.The test assumesthat the properties of the specimen are perfectly isotropic,which may not be true for some refractory materials.The testalso assumes that the specimen is homogeneous and elastic.Specimens that are micro-cracked are difficult to test since theydo not yield consistent results.Specimens with low densities1This test method is under the jurisdiction of ASTM Committee C08 onRefractories and is the direct responsibility of Subcommittee C08.01 on Strength.Current edition approved March 1,2012.Published April 2012.Originallyapproved in 2002.Last previous edition approved in 2007 as C1548 02(2007).DOI:10.1520/C1548-02R12.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 have a damping effect and are easily damaged locally at theimpact point.Insulating bricks can generally be tested with thistechnique,but fibrous insulating materials are generally tooweak and soft to test.4.2 For quality control use,the test method may be used formeasuring only resonant frequencies of any standard sizespecimen.An elastic modulus calculation may not be needed oreven feasible if the shape is non-standard,such as a slide gateplate containing a hole.Since specimens will vary in both sizeand mass,acceptable frequencies for each shape and materialmust be established from statistical data.4.3 Dimensional variations can have a significant effect onmodulus values calculated from the frequency measurements.Surface grinding may be required to bring some materials intothe specified tolerance r