1、Designation: E1530 11 (Reapproved 2016)Standard Test Method forEvaluating the Resistance to Thermal Transmission ofMaterials by the Guarded Heat Flow Meter Technique1This standard is issued under the fixed designation E1530; the number immediately following the designation indicates the year oforigi
2、nal 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 a steady-state technique for thedetermin
3、ation of the resistance to thermal transmission (ther-mal resistance) of materials of thicknesses less than 25 mm.For homogeneous opaque solid specimens of a representativethickness, thermal conductivity can be determined (see Note1). This test method is useful for specimens having a thermalresistan
4、ce in the range from 10 to 400 10-4m2KW-1, whichcan be obtained from materials of thermal conductivity in theapproximate range from 0.1 to 30 Wm-1K-1over the approxi-mate temperature range from 150 to 600 K. It can be usedoutside these ranges with reduced accuracy for thicker speci-mens and for ther
5、mal conductivity values up to 60 Wm-1K-1.NOTE 1A body is considered homogeneous when the property to bemeasured is found to be independent of specimen dimensions.1.2 This test method is similar in concept to Test MethodC518, but is modified to accommodate smaller test specimens,having a higher therm
6、al conductance. In addition, significantattention has been paid to ensure that the thermal resistance ofcontacting surfaces is minimized and reproducible.1.3 The values stated in SI units are to be regarded asstandard. The additional values are mathematical conversionsto inch-pound units that are pr
7、ovided for information only andare not considered standard.1.4 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-bi
8、lity of regulatory limitations prior to use.2. Related Documents2.1 ASTM Standards:2C518 Test Method for Steady-State Thermal TransmissionProperties by Means of the Heat Flow Meter ApparatusC1045 Practice for Calculating Thermal Transmission Prop-erties Under Steady-State ConditionsE220 Test Method
9、for Calibration of Thermocouples ByComparison TechniquesE1142 Terminology Relating to Thermophysical PropertiesE1225 Test Method for Thermal Conductivity of SolidsUsing the Guarded-Comparative-Longitudinal Heat FlowTechniqueF104 Classification System for Nonmetallic Gasket Materi-alsF433 Practice fo
10、r Evaluating Thermal Conductivity of Gas-ket Materials3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 heat flux transducer (HFT)a device that produces anelectrical output that is a function of the heat flux, in apredefined and reproducible manner.3.1.2 thermal conductance (C)t
11、he time rate of heat fluxthrough a unit area of a body induced by unit temperaturedifference between the body surfaces.3.1.2.1 average temperature of a surfacethe area-weighted mean temperature of that surface.3.1.2.2 average (mean) temperature of a specimen (discshaped)the mean value of the upper a
12、nd lower face tempera-tures.3.1.3 thermal conductivity ()(of a solid material)thetime rate of heat flow, under steady conditions, through unitarea, per unit temperature gradient in the direction perpendicu-lar to the area:3.1.3.1 apparent thermal conductivitywhen other modesof heat transfer through
13、a material are present in addition toconduction, the results of the measurements performed inaccordance with this test method will represent the apparent oreffective thermal conductivity for the material tested.3.1.4 thermal resistance (R)the reciprocal of thermal con-ductance.1This test method is u
14、nder the jurisdiction ofASTM Committee E37 on ThermalMeasurements and is the direct responsibility of Subcommittee E37.05 on Thermo-physical Properties.Current edition approved Sept. 1, 2016. Published September 2016. Originallyapproved in 1993. Last previous edition approved in 2011 as E1530 11. DO
15、I:10.1520/E1530-11R16.2For 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
16、Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2 Symbols: = thermal conductivity, Wm-1K-1or Btuin.h-1ft-2F-1C = thermal conductance, Wm-2K-1or Btuh-1ft-2F-1R = thermal resistance, m2KW-1or hft2FBtu-1x = specimen thickness, mm or inA = specimen cross-sectional area, m2or
17、 ft2Q = heat flow, W or Btuh-1 = heat flux transducer output, mVN = heat flux transducer calibration constant, Wm-2mV-1or Btuh-1ft-2mV-1N = heat flux, Wm2or Btuh-1ft2T = temperature difference, C or FTg= temperature of guard heater, C or FTu= temperature of upper heater, C or FTl= temperature of low
18、er heater, C or FT1= temperature of one surface of the specimen, C or FT2= temperature of the other surface of the specimen, C orFTm= mean temperature of the specimen, C or Fs= unknown specimenr= known calibration or reference specimeno= contacts4. Summary of Test Method4.1 A specimen and a heat flu
19、x transducer (HFT) aresandwiched between two flat plates controlled at differenttemperatures, to produce a heat flow through the test stack. Areproducible load is applied to the test stack by pneumatic orother means, to ensure that there is a reproducible contactresistance between the specimen and p
20、late surfaces. A guardsurrounds the test stack and is maintained at a uniform meantemperature of the two plates, in order to minimize lateral heatflow to and from the stack. At steady state, the difference intemperature between the surfaces contacting the specimen ismeasured with temperature sensors
21、 embedded in the surfaces,together with the electrical output of the HFT. This output(voltage) is proportional to the heat flow through the specimen,the HFT and the interfaces between the specimen and theapparatus. The proportionality is obtained through prior cali-bration of the system with specime
22、ns of known thermalresistance measured under the same conditions, such thatcontact resistance at the surfaces is made reproducible.5. Significance and Use5.1 This test method is designed to measure and comparethermal properties of materials under controlled conditions andtheir ability to maintain re
23、quired thermal conductance levels.6. Apparatus6.1 Aschematic rendering of a typical apparatus is shown inFig. 1. The relative position of the HFT to the specimen is notimportant (it may be on the hot or cold side) as the test methodis based on maintaining axial heat flow with minimal radialheat loss
24、es or gains. It is also up to the designer whether tochoose heat flow upward or downward or horizontally, al-though downward heat flow in a vertical stack is the mostcommon one.6.2 Key Components of a Typical Device (The numbers 1 to22 in parentheses refer to Fig. 1):6.2.1 The compressive force for
25、the stack is to be providedby either a regulated pneumatic or hydraulic cylinder (1), deadweights or a spring loaded mechanism. In either case, meansFIG. 1 Key Components of a Typical DeviceE1530 11 (2016)2must be provided to ensure that the loading can be varied andset to certain values reproducibl
26、y.6.2.2 The loading force must be transmitted to the stackthrough a gimball joint (2) that allows up to 5 swivel in theplane perpendicular to the axis of the stack.6.2.3 Suitable insulator plate (3) separates the gimball jointfrom the top plate (4).6.2.4 The top plate (assumed to be the hot plate fo
27、r thepurposes of this description) is equipped with a heater (5) andcontrol thermocouple (6) adjacent to the heater, to maintain acertain desired temperature. (Other means of producing andmaintaining temperature may also be used as long as therequirements in 6.3 are met.) The construction of the top
28、 plateis such as to ensure uniform heat distribution across its facecontacting the specimen (8). Attached to this face (or embed-ded in close proximity to it) in a fashion that does not interferewith the specimen/plate interface, is a temperature sensor (7)(typically a thermocouple, resistance therm
29、ometer, or a therm-istor) that defines the temperature of the interface on the plateside.6.2.5 The specimen (8) is in direct contact with the top plateon one side and an intermediate plate (9) on the other side.6.2.6 The intermediate plate (9) is an optional item. Itspurpose is to provide a highly c
30、onductive environment to thesecond temperature sensor (10), to obtain an average tempera-ture of the surface. If the temperature sensor (10) is embeddedinto the face of the HFT, or other means are provided to definethe temperature of the surface facing the specimen, the use ofthe intermediate plate
31、is not mandatory.6.2.7 The heat flux transducer (HFT) is a device that willgenerate an electrical signal in proportion to the heat fluxacross it. The level of output required (sensitivity) greatlydepends on the rest of the instrumentation used to read it. Theoverall performance of the HFTand its rea
32、dout instrumentationshall be such as to meet the requirements in Section 13.6.2.8 The lower plate (12) is constructed similarly to theupper plate (4), except it is positioned as a mirror image.6.2.9 An insulator plate (16) separates the lower plate (12)from the heat sink (17). In case of using circu
33、lating fluid inplace of a heater/thermocouple arrangement in the upper orlower plates, or both, the heat sink may or may not be present.6.2.10 The entire stack is surrounded by a guard whosecross section is not too much different from the stacks (18)equipped with a heater or cooling coils (19), or b
34、oth, and acontrol thermocouple, resistance thermometer or thermistor(20) to maintain it at the mean temperature between the upperand lower plates. A small, generally unfilled, gap separates theguard from the stack. For instruments limited to operate in theambient region, no guard is required but a d
35、raft shield isrecommended in place of it.NOTE 2It is permissible to use thin layers of high-conductivity greaseor elastomeric material on the two surfaces of the specimen to reduce thethermal resistance of the interface and promote uniform thermal contactacross the interface area.NOTE 3The cross-sec
36、tional area and the shape of the specimen maybe any, however, most commonly circular and rectangular cross sectionsare used. Minimum size is dictated by the magnitude of the disturbancecaused by thermal sensors in relation to the overall flux distribution. Themost common sizes are 25 mm round or squ
37、are to 50 mm round.6.2.11 The instrument is preferably equipped with suitablemeans (21) to measure the thickness of the specimen, in situ, inaddition to provisions (22) to limit compression when testingelastomeric or other compressible materials.NOTE 4This requirement is also mandatory for testing m
38、aterials thatsoften while heated.6.3 Requirements:6.3.1 Temperature control of upper and lower plate is to be60.1C (0.18F) or better.6.3.2 Reproducible load of 0.28 MPa (40 psi) has beenfound to be satisfactory for solid specimens. Minimum loadshall not be below 0.07 MPa (10 psi).6.3.3 Temperature s
39、ensors are usually fine gage or small-diameter sheath thermocouples, however, ultraminiature resis-tance thermometers and linear thermistors may also be used.6.3.4 Operating range of a device using a mean temperatureguard shall be limited to from 100 to 300C, when usingthermocouples as temperature s
40、ensors, and from 180 to300C when platinum resistance thermometers are used.Thermistors are normally present on more restricted allowabletemperature range of use.7. Sampling and Conditioning7.1 Cut representative test specimens from larger pieces ofthe sample material or body.7.2 Condition the cut sp
41、ecimens in accordance with therequirements of the appropriate material specifications, if any.8. Test Specimen8.1 The specimen to be tested should be representative forthe sample material. The recommended specimen configura-tion is a 50.8 6 0.25 mm (2 6 0.010 in.) diameter disk, havingsmooth flat an
42、d parallel faces, 60.025 mm (60.001 in.), suchthat a uniform thickness within 60.025 mm (60.001 in.) isattained in the range from 0.5 to 25.4 mm (0.020 to 1.0 in.) Fortesting specimens with thicknesses below 0.5 mm, a specialtechnique, described in Annex A1, has to be used. Otherfrequently favored s
43、izes are 25.4 mm (1.00 in.) round or squarecross section.9. Calibration9.1 Select the mean temperature and load conditions re-quired. Adjust the upper heater temperature (Tu) and lowerheater temperature (Tl) such that the temperature difference atthe required mean temperature is no less than 30 to 3
44、5C andthe specimen T is not less than 3C. Adjust the guard heatertemperature (Tg) such that it is at approximately the average ofTuand Tl.9.2 Select at least three calibration specimens having ther-mal resistance values that bracket the range expected for thetest specimens at the temperature conditi
45、ons required.9.3 Table 1 contains a list of several available materialscommonly used for calibration together with correspondingthermal resistance (Rs) values for a given thickness. Thisinformation is provided to assist the user in selecting optimumspecimen thickness for testing a material and in de
46、ciding whichcalibration specimens to use.E1530 11 (2016)39.4 The range of thermal conductivity for which this testmethod is most suitable is such that the optimum thermalresistance range is from 10 10-4to 400 10-4m2KW-1.The most commonly used calibration materials are the Pyrex7740 and Pyroceram 960
47、6,3Vespel4(polyimide) and stainlesssteel all having well-established thermal conductivity behav-iors with temperature.9.5 Table 2 and Table 3 are listing thermal conductivityvalues for selected reference materials, with the appropriatebibliographic references appearing in bold characters. Thetempera
48、ture range listed for each reference material corre-sponds to the temperature range mentioned in each particularcited work, and in some cases exceeds the applicable tempera-ture range for this test method. The information was, however,considered useful for the general user, and for that reason itwas
49、 listed for the entire temperature range applicable to eachreference material.10. Procedure10.1 Measure the thickness of the calibration specimen to25 m using a suitable caliper or gauge stand.10.2 Coat both surfaces of a calibration specimen with avery thin layer of a compatible heat transfer compound or placea thin layer of elastomeric heat-transfer medium on it to helpminimize the thermal resistance at the interfaces of adjacentcontacting surfaces.10.3 Release the compressive load on the speci
