1、Designation: C 1470 06Standard Guide forTesting the Thermal Properties of Advanced Ceramics1This standard is issued under the fixed designation C 1470; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A nu
2、mber in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers the thermal property testing of ad-vanced ceramics, to include monolithic ceramics, particulate/whisker-reinforced cer
3、amics, and continuous fiber-reinforcedceramic composites. It is intended to provide guidance andinformation to users on the special considerations involved indetermining the thermal properties of these ceramic materials.1.2 Five thermal properties (specific heat capacity, thermalconductivity, therma
4、l diffusivity, thermal expansion, andemittance/emissivity) are presented in terms of their definitionsand general test methods. The relationship between thermalproperties and the composition, microstructure, and processingof advanced ceramics (monolithic and composite) is brieflyoutlined, providing
5、guidance on which material and specimencharacteristics have to be considered in evaluating the thermalproperties of advanced ceramics. Additional sections describesampling considerations, test specimen preparation, and report-ing requirements.1.3 Current ASTM test methods for thermal properties aret
6、abulated in terms of test method concept, testing range,specimen requirements, standards/reference materials, capa-bilities, limitations, precision, and special instructions formonolithic and composite ceramics.1.4 This guide is based on the use of current ASTMstandards for thermal properties where
7、appropriate and on thedevelopment of new test standards where necessary. It is notthe intent of this guide to rigidly specify particular thermal testmethods for advanced ceramics. Guidance is provided on howto utilize the most commonly available ASTM thermal testmethods, considering their capabiliti
8、es and limitations.1.5 The values stated in SI units are to be regarded as thestandard per IEEE/ASTM SI 10.1.6 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 a
9、nd health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:22.1.1 Specific Heat:C 351 Test Method for Mean Specific Heat of ThermalInsulationD 2766 Test Method for Specific Heat of Liquids and SolidsE 1269 Test Method for Det
10、ermining Specific Heat Capac-ity by Differential Scanning Calorimetry2.1.2 Thermal Conductivity:C 177 Test Method for Steady-State Heat Flux Measure-ments and Thermal Transmission Properties by Means ofthe Guarded-Hot-Plate ApparatusC 182 Test Method for Thermal Conductivity of InsulatingFirebrickC
11、201 Test Method for Thermal Conductivity of Refracto-riesC 202 Test Method for Thermal Conductivity of RefractoryBrickC 408 Test Method for Thermal Conductivity of WhitewareCeramicsC 518 Test Method for Steady-State Thermal TransmissionProperties by Means of the Heat Flow Meter ApparatusC 767 Test M
12、ethod for Thermal Conductivity of CarbonRefractoriesC 1044 Practice for Using a Guarded-Hot-Plate Apparatusor Thin-Heater Apparatus in the Single-Sided ModeC 1045 Practice for Calculating Thermal TransmissionProperties Under Steady-State ConditionsC 1113 Test Method for Thermal Conductivity of Refra
13、cto-ries by Hot Wire (Platinum Resistance Thermometer Tech-nique)C 1114 Test Method for Steady-State Thermal TransmissionProperties by Means of the Thin-Heater ApparatusC 1130 Practice for Calibrating Thin Heat Flux TransducersE 1225 Test Method for Thermal Conductivity of Solids byMeans of the Guar
14、ded-Comparative-Longitudinal HeatFlow Technique1This guide is under the jurisdiction of ASTM Committee C28 on AdvancedCeramics and is the direct responsibility of Subcommittee C28.03 on PhysicalProperties and Performance.Current edition approved Jan. 1, 2006. Published February 2006. Originallyappro
15、ved in 2000. Last previous edition approved in 2000 as C 1470 00.2For 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 webs
16、ite.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.E 1530 Test Method for Evaluating the Resistance to Ther-mal Transmission of Materials by the Guarded Heat FlowMeter Technique2.1.3 Thermal Expansion:C 372 Test Method for Linear Th
17、ermal Expansion of Por-celain Enamel and Glaze Frits and Fired Ceramic Whitew-are Products by the Dilatometer MethodC 1300 Test Method for Linear Thermal Expansion ofGlaze Frits and Ceramic Whiteware Materials by theInterferometric MethodE 228 Test Method for Linear Thermal Expansion of SolidMateria
18、ls With a Vitreous Silica Dilatometer3E 289 Test Method for Linear Thermal Expansion of RigidSolids with InterferometryE 831 Test Method for Linear Thermal Expansion of SolidMaterials by Thermomechanical Analysis2.1.4 Thermal Diffusivity:C 714 Test Method for Thermal Diffusivity of Carbon andGraphit
19、e by Thermal Pulse MethodE 1461 Test Method for Thermal Diffusivity by the FlashMethod2.1.5 Emittance/Emissivity:E 408 Test Methods for Total Normal Emittance of SurfacesUsing Inspection-Meter TechniquesE 423 Test Method for Normal Spectral Emittance at El-evated Temperatures of Nonconducting Specim
20、ens2.1.6 General Standards:C 373 Test Method for Water Absorption, Bulk Density,Apparent Porosity, and Apparent Specific Gravity of FiredWhiteware ProductsC 1145 Terminology of Advanced CeramicsE 122 Practice for Calculating Sample Size to Estimate,With a Specified Tolerable Error, the Average for a
21、Characteristic of a Lot or ProcessE 473 Terminology Relating to Thermal Analysis and Rhe-ologyE 1142 Terminology Relating to Thermophysical PropertiesC 1045 Practice for Calculating Thermal TransmissionProperties Under Steady-State ConditionsIEEE/ASTM SI 10 Standard for Use of the InternationalSyste
22、m of Units (SI) (The Modern Metric System)3. Terminology3.1 Definitions:3.1.1 advanced ceramic, na highly engineered, high-performance, predominantly nonmetallic, inorganic, ceramicmaterial having specific functional attributes. (C 1145)3.1.2 ceramic matrix composite, na material consisting oftwo or
23、 more materials (insoluble in one another), in which themajor continuous component (matrix component) is a ceramic,while the secondary component/s (reinforcing component) maybe ceramic, glass-ceramic, glass, metal, or organic in nature.These components are combined on a macroscale to form auseful en
24、gineering material possessing certain properties orbehavior not possessed by the individual constituents.(C 1145)3.1.3 coeffcient of linear thermal expansion, aT-1, nthechange in length, relative to the length of the specimen,accompanying a unit change of temperature, at a specifiedtemperature. This
25、 property can also be considered the instan-taneous expansion coefficient or the slope of the tangent to theDL/L versus T curve at a given temperature. (E 1142)3.1.4 continuous fiber-reinforced ceramic composite(CFCC), na ceramic matrix composite in which the reinforc-ing phase(s) consists of contin
26、uous filaments, fibers, yarns, orknitted or woven fabric. (C 1145)3.1.5 differential scanning calorimetry (DSC), na tech-nique in which the difference in energy inputs into a testspecimen and a reference material is measured as a function oftemperature while the test specimen and reference material
27、aresubjected to a controlled temperature program. (E 1269)3.1.6 discontinuous fiber-reinforced ceramic composite,na ceramic matrix composite reinforced by chopped fibers.(C 1145)3.1.7 emittance (emissivity), e (nd), nthe ratio of theradiant flux emitted by a specimen per unit area to the radiantflux
28、 emitted by a black body radiator at the same temperatureand under the same conditions. Emittance ranges from 0 to 1,with a blackbody having an emittance of 1.00. (E 423)3.1.8 linear thermal expansion, nd, nthe change inlength per unit length resulting from a temperature change.Linear thermal expans
29、ion is symbolically represented by DL/L0, where DL is the observed change in length DL=L2 L1,and L0, L1, and L2are the lengths of the specimen at referencetemperature T0and test temperatures T1and T2. (E 228)3.1.9 mean coeffcient of linear thermal expansion, aLT-1,nthe change in length, relative to
30、the length of the specimen,accompanying a unit change of temperature measured across aspecified temperature range (T1to T2). (C 372)3.1.10 particulate reinforced ceramic matrix composite,na ceramic matrix composite reinforced by ceramic particu-lates. (C 1145)3.1.11 specific heat (specific heat capa
31、city), C mL1T2u1,nthe quantity of heat required to provide a unit temperatureincrease to a unit mass of material. (E 1142)3.1.12 thermal conductivity, l mLT1u1, nthe time rateof heat flow, under steady conditions, through unit area, perunit temperature gradient in the direction perpendicular to thea
32、rea. (E 1142)3.1.13 thermal diffusivity, L2T1, nthe property given bythe thermal conductivity divided by the product of the bulkdensity and heat capacity per unit mass. (E 1461)3.1.14 thermodilatometry, na technique in which a di-mension of a test specimen under negligible applied force ismeasured a
33、s a function of temperature while the test specimenis subjected to a controlled temperature program in a specifiedatmosphere. (E 473)3.2 Units for Thermal Properties:Property SI Units AbbreviationSpecific heat capacity joules/(gram-kelvin) J/(gK)Thermal Conductivity watts/(metre-kelvin) W/(mK)Therma
34、l diffusivity metre/second2m/s2Coefficient of ThermalExpansionmetre/(metre-kelvin) K1Emittance/emissivity no dimensions 3Withdrawn.C14700624. Summary of Guide4.1 Five thermal properties (specific heat capacity, thermalconductivity, thermal diffusivity, thermal expansion, andemittance/emissivity) are
35、 presented in terms of their definitionsand general test methods. The relationship between thermalproperties and the composition, microstructure, and processingof advanced ceramics is briefly outlined, providing guidanceon which material characteristics have to be considered inevaluating the thermal
36、 properties. Additional sections describesampling considerations, test specimen preparation, and report-ing requirements.4.2 Current ASTM test methods for thermal properties aretabulated in terms of test method concept, testing range,specimen requirements, standards/reference materials, capa-bilitie
37、s, limitations, precision, and special instructions formonoliths and composites.5. Significance and Use5.1 The high-temperature capabilities of advanced ceramicsare a key performance benefit for many demanding engineeringapplications. In many of those applications, advanced ceramicswill have to perf
38、orm across a broad temperature range. Thethermal expansion, thermal diffusivity/conductivity, specificheat, and emittance/emissivity are crucial engineering factorsin integrating ceramic components into aerospace, automotive,and industrial systems5.2 This guide is intended to serve as a reference an
39、dinformation source for testing the thermal properties of ad-vanced ceramics, based on an understanding of the relation-ships between the composition and microstructure of thesematerials and their thermal properties.5.3 The use of this guide assists the testing community incorrectly applying theASTM
40、 thermal test methods to advancedceramics to ensure that the thermal test results are properlymeasured, interpreted, and understood. This guide also assiststhe user in selecting the appropriate thermal test method toevaluate the particular thermal properties of the advancedceramic of interest.5.4 Th
41、e thermal properties of advanced ceramics are criticaldata in the development of ceramic components for aerospace,automotive, and industrial applications. In addition, the effectof environmental exposure on thermal properties of the ad-vanced ceramics must also be assessed.6. Procedure6.1 Review Sec
42、tions 7-10 to become familiar with thermalproperty concepts and thermal testing issues for advancedceramics, specimen preparation guidance, and reporting rec-ommendations.6.2 Review the test method text and tables in Section 11 forthe property you need to determine. Use the text and tables tohelp se
43、lect the most appropriate ASTM test method forevaluating the thermal property of interest for the specificadvanced ceramic.6.3 Perform the thermal property test in accordance with theselected ASTM test method, but refer back to the guide fordirections and recommendations on material characterization
44、,sampling procedures, test specimen preparation, and reportingresults.7. Thermal Properties and Their Measurement7.1 Specific Heat Capacity:7.1.1 Specific heat capacity is the amount of energy requiredto increase the temperature by one unit for a unit mass ofmaterial. It is a fundamental thermal pro
45、perty for engineers andscientists in determining the temperature response of materialsto changes in heat flux and thermal conditions. The SI units forspecific heat capacity are joules/(gramK). Since the specificheat capacity changes with temperature, a specific heat capac-ity value must always be as
46、sociated with a specific testtemperature or temperature range.7.1.2 Specific heat capacity is commonly measured bycalorimetry in which changes in thermal energy are measuredagainst changes in temperature. The two common calorimetrymethods are differential scanning calorimetry and drop calo-rimetry.7
47、.1.3 Differential scanning calorimetry heats the test mate-rial at a controlled rate in a controlled atmosphere through thetemperature region of interest. The heat flow into the testmaterial is compared to the heat flow into a reference materialto determine the energy changes in the test material as
48、 afunction of temperature.7.1.4 In drop calorimetry, the test sample is heated to thedesired temperature and then immersed in an instrumented,liquid-filled container (calorimeter), which reaches thermalequilibrium. The increase in temperature of the calorimeterliquid/container is a measure of the am
49、ount of heat in the testspecimen.7.1.5 In any calorimetry test, the experimenter must recog-nize that phase changes and other thermo-physical transforma-tions in the material will produce exothermic and endothermicevents which will be captured in the test data. The thermalevents must be properly identified and understood within thecontext of the material properties, chemistry, and phase com-position across the temperature range of interest.7.2 Thermal Conductivity:7.2.1 Thermal conductivity is a measurement of the rate ofheat flow through a ma
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