1、Designation: E1225 09E1225 13Standard Test Method forThermal Conductivity of Solids by Means of Using theGuarded-Comparative-Longitudinal Heat Flow Technique1This standard is issued under the fixed designation E1225; the number immediately following the designation indicates the year oforiginal adop
2、tion 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.This standard has been approved for use by agencies of the Department of Defense.1.
3、Scope1.1 This test method describes a steady state technique for the determination of the thermal conductivity, , of homogeneous-opaque solids (see Notes 1 and 2). This test method is for applicable to materials with effective thermal conductivities in theapproximate range 0.2 200022 to 55 to 8M Dep
4、endent on TA NISTAAustenitic StainlessSRM 735200 to 1200 300 KF = 2.331 + 515.2 T14 for T 300 KG = 3.65367 6.64042 10-4T 218.937T1 + 116163 T2 GFused SilicaH 1300 200 KKE,K = 1.1036 + 1.659 x 10-3 (T-273.15) 3.982x 10-6 (T-273.15)2 + 6.746 x 10-9 (T-273.15)3KKIRMM,Belgium3 for T from 140 K to 200KK3
5、10 Stainless Steel 300 to 1000 4 = 12.338 + 1.781 x 10-2 (T-273.15)L NPL430 Stainless Steel 300 to 1070 4 = 20.159 + 1.589 x 10-2 (T-273.15) -1.283 x10-5 (T-273.15)2LNPLInconel 600 300 to 1000 4 = 12.479 + 1.648 x 10-2 (T-273.15) + 3.741x 10-6 (T-273.15)2 LNPLNimonic 75 300 to 1000 4 = 11.958 + 1.65
6、7 x 10-2 (T-273.15) + 3.252x 10-6 (T-273.15)2LNPLTABLE 1 Reference Materials For Use as Meter BarsMaterial TemperatureRange (K)PercentageUncertainty( %)Thermal Conductivity(W/mK)Electrolytic IronA,B 2 to 1000 2 See Table 3.TungstenC 4 to 300300 to 2000200022 to 55 to 8See Table 4.Austenitic Stainles
7、sD200 to 1200 300 K = 3.65367 6.64042 10-4T 218.937T1 + 116163 T2Fused SilicaL,M 1300 200 K = 1.1036 + 1.659 x 10-3 (T-273.15) 3.982x 10-6 (T-273.15)2 + 6.746 x 10-9 (T-273.15)3K310 Stainless SteelK,R 300 to 1020 4 = 12.338 + 1.781 x 10-2 (T-273.15)430 Stainless SteelK,R 300 to 770 4 = 20.159 + 1.58
8、9 x 10-2 (T-273.15) -1.283 x10-5 (T-273.15)2Inconel 600S,K,R 300 to 1020 4 = 12.479 + 1.648 x 10-2 (T-273.15) + 3.741x 10-6 (T-273.15)2Nimonic 75T,K,R 300 to 1020 4 = 11.958 + 1.657 x 10-2 (T-273.15) + 3.252x 10-6 (T-273.15)2A National SRM 8420 is available from National Institute of Standards and T
9、echnology, Washington, D.C. 20234. Technology (NIST), Gaithersburg, MD.USee SpecialPublications 260-52 and 260-46.B Fulkerson W., et al., Hurst, J. G., Physics Reviewand Lankford, 167, p. 765, (1968).A. B., “Report of Investigation, Research Materials 8420 and 8421, Electrolytic Iron,Thermal Conduct
10、ivity and Electrical Resistivity as a Function of Temperature from 2 to 1000K,” National Institutes of Standards and Technology (nee National Bureau ofStandards), Gaithersburg, MD, 1984.C Lucks C. F., Journal Hurst, J. G., and Giarratano, P. J., Certificate, Standard Reference Material 730, Thermal
11、Conductivity Tungsten, National Institutes of Testing andEvaluation, ASTM 1 (5), 422 (1973).Standards and Technology (nee National Bureau of Standards), Gaithersburg, MD, 1976.D Hurst, J. G., Sparks, L. L., and Giaarratano, P. J., Certificate, Standard Reference Material 735, Thermal Conductivity Au
12、stenitic Stainless Steel, National Institutesof Standards and technology (nee National Bureau of Standards), Gaithersburg, MD,USA, 1975.E Moore, J. P., Graves, R. S.S., and McElroy, D. L., “Thermal Conductivity and Electrical Resistivity of High-Purity Copper from 78 to 400 K,” Canadian Journal of P
13、hysics,45, 3849 (1967).Vol 45, 1967, pp. 38493865.F “Thermal Conductivity of Selected Materials,” Report NSRDS-NBS 8, National Bureau of Standards, 1966.Pyroceram is a trademark by Corning Incorporated, Corning,NY.E1225 135G D. R. Salmon, G. Roebben, R. Brandt, 2007. Salmon, D. R., Roebben, G., and
14、Brandt,R., “Certification of Thermal Conductivity and Thermal Diffusivity up to 1025 Kof Glass-Ceramic Reference Material BCR-720,” EUR Report 21764, IRMM, Geel, Belgium.Institute for Reference Materials and Measurements (IRMM), Geel, Belgium,2007.H D. E. Stroe, M.A.Thermitus, R.A. Stroe, D. E.,Ther
15、mitus, M.A., and Jacobs Fedore, in R.A., “Thermophysical Properties of Pyroceram 9606,” Thermal Conductivity27 / Thermal Expansion 15, H. H. Wang, W. Porter, eds., DEStech Publications, Inc., Lancaster, PA, USA, 2004, 2005, pp. 382-390.382390.I Hust J. G., Cryogenics Division; NBS, Boulder, Colorado
16、 80302. BCR-2013 is available from the Institute for Reference Materials and Measurements (IRMM), Geel,Belgium.UJ BCR-724 is available from the Laboratory of the Government Chemists (LGC), Teddington, Middlesex, UK.UKTye, R. P., and Salmon, D. R., “Development of New Thermal Conductivity Reference M
17、aterials: A Summary of Recent Contributions by National Physical Laboratory,”Thermal Conductivity 27/ Thermal Expansion 15, H. Wang (ed.), DEStech Publications, Lancaster PA, 2005, pp. 372381.L Above 700 K a large fraction of heat conduction in fused silica will be by radiation and the actual effect
18、ive values may depend on the emittances of bounding surfacesand meter bar size.M Recommended values from Table 3017A-R-2 of the Thermophysical Properties Research Center Data Book, Vol. 3, “Nonmetallic Elements, Compounds, and Mixtures,”Purdue University, Lafayette, Indiana.NPyrex is a trademark by
19、Corning Incorporated, Corning, NY.O R. P. Tye, D. R. Salmon, in Tye, R. P., and Salmon, D. R., “Thermal Conductivity Certified Reference Materials: Pyrex 7740 and Polymethylmethacrylate,” ThermalConductivity 26 / Thermal Expansion 14, 14, Ralph Dinwiddie R. Dinwiddie, ed., DEStech Publications, Inc.
20、, Lancaster, PA, USA, 2005, pp. 437-451 437451.P BCR-39 is available from the Institute for Reference Materials and Measurements (IRMM), Geel, Belgium.UQ Salmon, D., “Thermal Conductivity of Insulations Using Guarded Hot Plates, including Recent Developments and Sources of Reference Materials,” Meas
21、urementScience and Technology, Vol 12, 2001, pp. R89R98.R J. Clark, R.Tye, Clark, J., andTye, R., “Thermophysical Properties Reference Data for Some Key EngineeringAlloy,” High Temperatures High Pressures, 2003 / 2004,volume 35/36, pp. 1-14.Vols 35/36, 2003/2004, pp. 114.SInconel is a trademark by S
22、pecial Metals Corporation, Huntington WV.TNimonic is a trademark by Special Metals Corporation, Huntington WV.U This is the sole source of supply of this material known to the committee at this time. If you are aware of alternative suppliers, please provide this information to ASTMInternational Head
23、quarters. Your comments will receive careful consideration at a meeting of the responsible technical committee,1 which you may attend.TABLE 3 Thermal Conductivity of Electrolytic IronATemperature,KThermal Conductivity,(W/mK)2 12.323 18.484 24.625 30.766 36.887 42.978 49.09 55.010 61.012 72.814 84.21
24、6 95.218 105.720 115.725 137.430 153.935 164.540 169.145 168.350 163.660 149.170 134.980 123.890 115.4100 108.9150 92.7200 86.7250 81.5300 76.4400 67.5500 60.2600 53.6700 47.49800 41.96900 37.121000 32.98A Hurst, J. G., and Lankford, A. B., Report of Investigation, Research Materials8420 and 8421, E
25、lectrolytic Iron, Thermal Conductivity and Electrical Resistivity asa Function of Temperature from 2 to 1000K, National Institute of Standards andTechnology (nee Bureau of Standards), 1984.TABLE 4 Thermal Conductivity of TungstenATemperature,KThermal Conductivity,(W/mK)4 1546 2318 30610 37712 44414
26、50316 55318 59120 61830 58540 43850 33060 27570 24580 22990 218100 211120 202140 197160 194180 190200 187250 180300 172350 164400 157450 151500 146600 138700 132800 127900 1231000 1201200 1141400 1101600 1071800 1052000 1022200 1012400 992600 982800 973000 97A Hurst, J. G., and Giarratano, P. J., Ce
27、rtificate, Standard Reference Material 730,Thermal Conductivity Tungsten, National Institute of Standards and Technology(nee National Bureau of Standards), 1976.E1225 1366.2 Insulation Materials:6.2.1 A large variety of powder, particulate, and fiber materials exists for reducing both radial heat fl
28、ow in the column-guardannulus and surrounds, and for heat shunting along the column. Several factors must be considered during selection of the mostappropriate insulation. The insulation must be stable over the anticipated temperature range, have a low I, and be easy to handle.In addition, the insul
29、ation should not contaminate system components such as the temperature sensors, it must have low toxicity,and it should not conduct electricity. In general, powders and particulates are used since they pack readily. However, low densityfiber blankets can also be used.6.2.2 Some candidate insulations
30、 are listed in Table 2.6.3 Temperature Sensors:6.3.1 There shall be a minimum of two temperature sensors on each meter bar and two on the specimen. Whenever possible,the meter bars and specimen should each contain three sensors. The extra sensors are useful in confirming linearity of temperaturevers
31、us distance along the column, or indicating an error due to a temperature sensor decalibration.TABLE 5 Thermal Conductivity of Austenitic Stainless SteelATemperature,KThermal Conductivity,(W/mK)5 0.4666 0.5657 0.6768 0.7969 0.92110 1.0512 1.3214 1.5816 1.8618 2.1320 2.4025 3.0730 3.7235 4.3440 4.924
32、5 5.4750 5.9855 6.4560 6.8865 7.2870 7.6475 7.9780 8.2785 8.5590 8.8095 9.04100 9.25110 9.65120 9.99130 10.3140 10.6150 10.9160 11.1170 11.4180 11.6190 11.9200 12.1250 13.2300 14.3350 15.3400 16.2450 17.1500 17.9600 19.3700 20.6800 21.9900 23.01000 24.11100 25.11200 26.1A Hurst, J. G., Sparks, L. L.
33、, and Giarratano, P. J., Certificate, Standard ReferenceMaterial 735, Thermal Conductivity Austenitic Stainless Steel, Thermal Con-ductivity as a Function of Temperature (5 to 1200 K), National Institute ofStandards and Technology (nee National Bureau of Standards), 1975.E1225 1376.3.2 The type of t
34、emperature sensor depends on the system size, temperature range, and the system environment as controlledby the insulation, meter bars, specimen, and gas within the system. Any sensor possessing adequate accuracy may be used fortemperature measurement (2) and be used in large systems where heat flow
35、 perturbation by the temperature sensors would benegligible. Thermocouples are normally employed. Their small size and the ease of attachment are distinct advantages.6.3.3 When thermocouples are employed, they should be fabricated from wires which are 0.1 mm diameter or less. A constanttemperature r
36、eference shall always be provided for all cold junctions. This reference can be an ice-cold slurry (3), a constanttemperature zone box, or an electronic ice point reference. All thermocouples shall be fabricated from either calibratedthermocouple wire (4) or from wire that has been certified by the
37、supplier to be within the limits of error specified in Table 1 ofStandard E230.6.3.4 Thermocouple attachment is important to this technique in order to ensure that reliable temperature measurements aremade at specific points. The various techniques are illustrated in Fig. 3. Intrinsic junctions can
38、be obtained with metals and alloysby welding individual thermo-elements to the surfaces (Fig. 3a). Butt or bead welded thermocouples junctions can be rigidlyattached by peening, cementing, or welding in fine grooves or small holes (Fig. 3b, 3c, and 3d).6.3.5 In Fig. 3b, the thermocouple resides in a
39、 radial slot, and in Fig. 3c the thermocouple is pulled through a radial hole in thematerial. When a sheathed thermocouple or a thermocouple with both thermoelements in a two-hole electrical insulator is used,the thermocouple attachment shown in Fig. 3d can be used. In the latter three cases, the th
40、ermocouple should be thermallyTABLE 2 Suitable Thermal Insulation MaterialsMaterialA Typical Thermal Conductivity (W/(mK)300K 800K 1300KPoured PowdersDiatomaceous Earth 0.053 0.10 0.154Bubbled Alumina 0.21 0.37 0.41Bubbled Zirconia 0.19 0.33 0.37Vermiculite 0.07 0.16 .Perlite 0.050 0.17 .Blankets an
41、d FeltsAluminosilicate 60120 kg/m3 0.044 0.13 0.33Zirconia 6090 kg/m3 0.039 0.09 0.25A All materials listed can be used up to the 1300 K limit of the comparativelongitudinal except where noted.3aIntrinsic weld with separate temperature elements welded to specimen or meterbars so that signal is throu
42、gh the material.3bRadial slots on the flat surfaces to hold a bare wire or ceramic insulatedthermocouple sensor the may be bonded into slot.3cSmall radial hole drilled through the specimen or meter bar and non-insulated(permitted if the material is an electrical insulator) or insulated thermocouple
43、pulledthrough the hole.3dSmall Radial hole drilled part way through the specimen or meter bar and athermocouple pushed into the hole.NOTE 1In all cases the thermoelements should be thermally tempered or thermally grounded on the guard, or both, to minimize temperaturemeasurement errors due to heat f
44、low into or out of the hot junction.FIG. 3 Thermocouple AttachmentsE1225 138connected to the solid surface using a suitable glue or high temperature cement. All four of the procedures shown in Fig. 3 shouldinclude wire tempering on the surfaces, wire loops in isothermal zones, thermal wire grounds o
45、n the guard, or a combination ofall three (5).6.3.6 Since uncertainty in temperature sensor location leads to large errors, special care must be taken to determine the correctdistance between sensors and to calculate the possible error resulting from any uncertainty.6.4 Reduction of Contact Resistan
46、ce:6.4.1 This test method requires uniform heat transfer at the meter bar to specimen interfaces whenever the temperature sensorsare within a distance equal to rA from an interface (6). This requirement necessitates a uniform contact resistance across theadjoining areas of meter bars and specimens.
47、This is normally attained by use of an applied axial load in conjunction with aconducting medium at the interfaces. Measurements in a vacuum environment are not recommended, unless the vacuum is requiredfor protection purposes.6.4.2 For the relatively thin specimens normally used for materials havin
48、g a low thermal conductivity, the temperature sensorsmust be mounted close to the surface and in consequence the uniformity of contact resistance is critical. In such cases, a very thinlayer of a compatible highly conductive fluid, paste, soft metal foil, or screen shall be introduced at the interfa
49、ces.6.4.3 Means shall be provided for imposing a reproducible and constant load along the column with the primary purpose ofminimizing interfacial resistances at meter bar-specimen interfaces. Since the force applied to the column usually affects thecontact resistance, it is desirable that this force be variable to ensure that S does not change with force variation. This force canbe applied either pneumatically, hydraulically, by spring action, or by putting a dead weight on the column. The above loadmechan
