ASTM_C_1332_-_18.pdf

Designation:C133218Standard Practice forMeasurement of Ultrasonic Attenuation Coefficients ofAdvanced Ceramics by Pulse-Echo Contact Technique1This standard is issued under the fixed designation C1332;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 practice describes a procedure for measurement ofultrasonic attenuation coefficients for advanced structural ce-ramic materials.The procedure is based on a broadbandbuffered piezoelectric probe used in the pulse-echo contactmode and emitting either longitudinal or shear waves.Theprimary objective of this practice is materials characterization.1.2 The procedure requires coupling an ultrasonic probe tothe surface of a plate-like sample and the recovery of succes-sive front surface and back surface echoes(refer to Fig.3).Power spectra of the echoes are used to calculate the attenua-tion spectrum(attenuation coefficient as a function of ultra-sonic frequency)for the sample material.The transducerbandwidth and spectral response are selected to cover a rangeof frequencies and corresponding wavelengths that interactwith microstructural features of interest in solid test samples.1.3 The purpose of this practice is to establish fundamentalprocedures for measurement of ultrasonic attenuation coeffi-cients.These measurements should distinguish and quantifymicrostructural differences among solid samples and thereforehelp establish a reference database for comparing materials andcalibrating ultrasonic attenuation measurement equipment.1.4 This practice applies to monolithic ceramics and alsopolycrystalline metals.This practice may be applied to whiskerreinforced ceramics,particulate toughened ceramics,and ce-ramic composites provided that similar constraints on samplesize,shape,and finish are met as described herein for mono-lithic ceramics.1.5 This practice sets forth the constraints on sample size,shape,and finish that will assure valid attenuation coefficientmeasurements.Thispracticealsodescribestheinstrumentation,methods,and data processing procedures foraccomplishing the measurements.1.6 This practice is not recommended for highly attenuatingmaterials such as very thick,very porous,rough-surfacedmonolithics or composites.This practice is not recommendedfor highly nonuniform,heterogeneous,cracked,defective,orotherwise flaw-ridden samples that are unrepresentative of thenature or inherent characteristics of the material under exami-nation.1.7 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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2C1331 Test Method for Measuring Ultrasonic Velocity inAdvanced Ceramics with Broadband Pulse-Echo Cross-Correlation MethodE543 Specification for Agencies Performing NondestructiveTestingE664/E664M Practice for the Measurement of the ApparentAttenuation of Longitudinal Ultrasonic Waves by Immer-sion MethodE1316 Terminology for Nondestructive ExaminationsE1495/E1495M Guide for Acousto-Ultrasonic Assessmentof Composites,Laminates,and Bonded Joints2.2 ASNT Documents:3Recommended Practice SNT-TC-1A for NondestructiveTesting Personnel Qualification and CertificationANSI/ASNT CP-189 Standard for Qualification and Certifi-cation of Nondestructive Testing Personnel1This practice is under the jurisdiction of ASTM Committee E07 on Nonde-structive Testing and is the direct responsibility of Subcommittee E07.06 onUltrasonic Method.Current edition approved Feb.1,2018.Published February 2018.Originallyapproved in 1996.Last previous edition approved in 2013 as C1332 01(2013).DOI:10.1520/C1332-18.2For 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 fromAmerican Society for Nondestructive Testing(ASNT),P.O.Box28518,1711 Arlingate Ln.,Columbus,OH 43228-0518,http:/www.asnt.org.*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 estab