1、Designation: C539 84 (Reapproved 2016)Standard Test Method forLinear Thermal Expansion of Porcelain Enamel and GlazeFrits and Ceramic Whiteware Materials by InterferometricMethod1This standard is issued under the fixed designation C539; the number immediately following the designation indicates the
2、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 interferometric determin
3、a-tion of linear thermal expansion of premelted frits (porcelainenamel and glaze) and fired ceramic whiteware materials attemperatures lower than 1000C (1830F).1.2 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the use
4、r of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E289 Test Method for Linear Thermal Expansion of RigidSolids with Interferometry3. Significance and Use3.1 This
5、test method defines the thermal expansion ofporcelain enamel and glaze frits by the interferometric method.This determination is critical in avoiding crazing (cracking) ofthese glass coatings due to mismatching of the thermalexpansion between the coating and substrate materials.4. Apparatus4.1 Sampl
6、e Preparation Equipment:34.1.1 Glazed Porcelain Crucible, No. 0.4.1.2 Fireclay Crucible, 102 mm (4 in.) in diameter.4.1.3 Rotating Abrasive Grinding Wheel (a silicon carbidetype is satisfactory).4.2 Micrometer Calipers, having a sensitivity such that theindex can be read to 0.002 mm (0.0001 in.).4.3
7、 Measuring Apparatus, consisting of fused silica inter-ferometer plates, viewing apparatus, an electric furnace andcontrol, potentiometer, pyrometer, and a suitable monochro-matic light source of known wavelength.4.3.1 FurnaceThe furnace shall be a vertical electric tubefurnace controlled by rheosta
8、t or other means so the heatingrate of the furnace can be readily duplicated from roomtemperature to 1000C (1830F). The heating rate shall notexceed 3C (5.5F)/min.4.3.2 Temperature Measuring Instrument A calibratedplatinum versus platinum-rhodium thermocouple (or aChromel versus Alumel thermocouple
9、if it is frequently cali-brated) in conjunction with a potentiometer shall be used. Thepotentiometer shall be capable of being read to 2C (4F) andshall have automatic compensation for the temperature of thereference junction, or the reference junction shall be held at0C (32F) by means of an ice bath
10、.5. Test Specimens5.1 For frit samples, three test specimens shall be preparedas follows:5.1.1 Fill a No. 0 glazed porcelain crucible with frit, placethe filled crucible inside a 102-mm (4-in.) diameter fireclaycrucible partly filled with silica, and work the small crucibledown into the silica until
11、 approximately 75 % of the smallcrucible is below the level of the silica.5.1.2 Place the crucible assembly into a furnace at atemperature high enough to just melt the mass. Hold for 15 minafter the frit has reached the furnace temperature.5.1.3 Remove the crucible, rapidly transfer it to anotherfur
12、nace that is at the frit firing temperature, and cool in thefurnace at a rate not to exceed 60C (110F)/h.5.1.4 Break the small crucible open and break up thevitreous mass. Select six fragments from the interior of themass (to avoid side portions diluted by the ceramic crucible)1This test method is u
13、nder the jurisdiction ofASTM Committee B08 on Metallicand Inorganic Coatingsand is the direct responsibility of Subcommittee B08.12 onMaterials for Porcelain Enamel and Ceramic-Metal Systems.Current edition approved Nov. 1, 2016. Published November 2016. Originallyapproved in 1964. Last previous edi
14、tion approved in 2011 as C539 84 (2011).DOI: 10.1520/C0539-84R16.2For 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
15、ite.3An example of suitable test equipment and an inferometric method may befound in the paper by Merritt, G. E., “The Interference Method of MeasuringThermal Expansion,” Journal of Research, National Institute of Standards andTechnology, Vol 10, No. 1, January 1933, p. 59 (RP 515).A description of
16、a permissible automatic fringe recording device may be foundin the paper by Saunders, J. B., “An Apparatus for Photographing InterferencePhenomenon,” Journal of Research, National Institute for Standards andTechnology, Vol 35, No. 3, September 1945, p. 157 (RP 1668).Copyright ASTM International, 100
17、 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1having minimum conical dimensions of 3 mm (18 in.) at thebase and 6 mm (14 in.) high.5.2 For fired samples, break and select six samples havingminimum conical dimensions of 3 mm (18 in.) at the base and6mm(14 in.) in he
18、ight. For all samples, grind the base of theflat cones and cement the flat cone base to the flat end of a glassrod with heated sealing wax. Grind the piece to a finished coneby rotating the rod while the piece is held against a rotatingabrasive wheel (a silicon carbide type is satisfactory).5.2.1 Wh
19、en a reasonably symmetrical cone with a roundedtip is obtained, remove it from the rod by heating the wax or bypressure with the fingertips. Remove all sealing wax with aknife blade or abrasive paper.5.2.2 The test cone height may be of the order of 4.8 mm(316 in.). These bases must be smooth and fl
20、at. Use No. 0metallurgical paper to approach the desired figure and then usesuccessively finer papers until the final reduction is made witha No. 3/0 paper.6. Calibration of Furnace46.1 Using the following procedure, calibrate the furnacecontrols to obtain a heating rate of 3C (5.5F)/min:6.1.1 Prepa
21、re three conical spacers closely approximatingthe dimensions of the final test pieces described in Section 5.These spacers shall be ground from fragments of refractoryceramic known to have a softening temperature in excess of1000C (1830F).6.1.2 Assemble the upper and lower interferometer plateswith
22、three refractory spacers as described in Section 7, exceptfringe development is not necessary. Place this assembly in thefurnace test location. Center the hot junction of an 18 or20-gage thermocouple within the triangle formed by thespacers. It will usually be necessary to extend the thermo-couple o
23、ut through the top of the furnace tube. This thermo-couple temperature measurement equipment shall meet therequirements in 4.3.2.6.1.3 The output of this thermocouple shall be used toestablish corrections required in calibrating the furnace tem-perature measuring system. Both temperature values and
24、heat-ing rates shall be so corrected if differences exist.7. Procedure7.1 Assemble (outside the furnace) the three test piecesprepared as described in Section 5 between the two interfer-ometer plates as follows:7.1.1 Place the plate with the one frosted side down withinthe refractory specimen crucib
25、le.7.1.2 Place the three test pieces on this plate in an equilat-eral triangle.7.1.3 Lower the clear plate onto the test pieces keeping themark or notch identifying the wedge side in the up position.7.1.4 Set this assembly at a height comparable to that usedinside the furnace.7.2 Rotate the telescop
26、e and center it over the test specimenassembly. Direct the monochromatic light source down thetube. If four to eight fringes are present, the setup is correct. Iffewer or more fringes are present, adjust the cone heights. Insome cases, mere tapping of the specimen assembly willproduce the correct nu
27、mber of fringes. Carefully measure andrecord the height of each cone. Upon achieving the propernumber of fringes, place the refractory ring cover on thecrucible and recheck for fringes.7.3 Without rotating the crucible, gently lower it into thefurnace and onto the bottom support so the thermocouple
28、restsat the bottom of the crucible. Cover the top of the furnace witha quartz plate.7.4 Rotate the telescope and check the fringe pattern. Ifexcessive glare or poor contrast are present, adjust by movingthe quartz cover, moving the light source, or releveling thetelescope.NOTE 1Removal of the telesc
29、ope eyepiece should reveal a bright dot,which is the true image. This must be in the field or no fringes will beseen. If this bright dot of the true image is not seen when the eyepiece isremoved, a great deal of trial and error adjustment of the telescope tripodmust be made. A number of false images
30、 may also be present. These mustbe sorted out by inserting the eyepiece and checking to see if fringes arepresent. If no fringes are seen, the bright dot is a false image.7.5 Standardize the potentiometer if necessary and set thepotentiometer or other temperature measuring instrument to38C (100F).7.
31、6 Slowly heat the furnace to 38C (100F). Center thecross hair of the telescope upon any convenient fringe andrecord the temperature corresponding to each fifth fringe.7.7 Continue heating the furnace to maintain a 3C (5.5F)/min temperature rise or less. Below 100C a heating rate notexceeding 1.5C/mi
32、n is preferred. For frit samples, when thesoftening temperature has been reached, as shown by thefringes retreating for at least one fringe, immediately turn offthe furnace to avoid reaction with the quartz plates.8. Calculations8.1 Calculate the percentage of linear thermal expansion foreach readin
33、g as follows:L 5 n/200h!1Ac(1)where:L = linear thermal expansion, % from starting temperature,t0C, to temperature of observation, tC,n = number of fringes passing the reference point duringthe change from temperature t0to temperature t, = wavelength of the light source, m,h = height of the specimen
34、at temperature t0, cm, andAc= air correction from temperature t0to temperature t,%(see Table 1).8.2 Prepare a curve by plotting each temperature reading, t,on the horizontal axis against the corresponding percentageexpansion along the vertical axis.8.3 Calculate the mean coefficient of thermal expan
35、sion, E,for any temperature range, t2to t3C, within the limits of thetest, as follows:4Saunders, J. B., “Improved Interferometric Procedure with Application toExpansion Measurements,” Journal of Research, National Bureau of Standards, Vol23, No. 1, July 1939, p. 179 ( RP 1227).C539 84 (2016)2E 5 L/1
36、00t32 t2 !#(2)where:L = linear thermal expansion, from temperature t2C totemperature t3C as determined from the curve pre-pared in accordance with 7.2,%,t2= lower temperature in range t2to t3, andt3= higher temperature in range t2to t3.9. Report9.1 Report the following:9.1.1 Designation of material
37、tested,9.1.2 Method of preparation of test specimen, cooling rate,etc.,9.1.3 Identification of type of apparatus used,9.1.4 Data sheet showing:9.1.4.1 Form and height of test specimens,9.1.4.2 Wavelength of light source,9.1.4.3 Starting temperature,9.1.4.4 Corrected temperature at each reading,9.1.4
38、.5 Number of fringes, n, at each reading,9.1.4.6 Calculation, n/200h, for each reading,9.1.4.7 Air correction, Ac, for each reading,9.1.4.8 Percentage of expansion, L, computed for eachreading,9.1.5 The curve (see 8.2) showing temperature plottedagainst percentage of expansion, and9.1.6 Mean coeffic
39、ient of linear thermal expansion perdegree Celsius over the desired temperature ranges.10. Precision and Bias10.1 The precision and bias of this test method of measuringthe linear thermal expansion of porcelain enamel and glaze fritsare as specified in Test Method E289.TABLE 1 Air Corrections From 2
40、0C To Temperatures IndicatedAAtmospheric pressure, 760 mm Hg.Temperature,CAirCorrection, %Temperature,CAirCorrection, %Temperature,CAirCorrection, %Temperature,CAirCorrection, %20 0.0000 84 0.0049 175 0.0094 320 0.013821 0.0001 86 0.0050 178 0.0095 326 0.013922 0.0002 88 0.0051 331 0.014023 0.0003 8
41、9 0.0052 180 0.0096 335 0.014124 0.0004 183 0.009725 0.0005 90 0.0053 185 0.0098 340 0.014226 0.0006 92 0.0054 188 0.0099 343 0.014327 0.0007 94 0.0055 350 0.014428 0.0008 96 0.0056 190 0.0100 354 0.014529 0.0009 97 0.0057 194 0.0101 359 0.014698 0.0058 197 0.010230 0.0010 364 0.014732 0.0011 102 0.
42、0059 200 0.0103 369 0.014833 0.0012 103 0.0060 202 0.0104 374 0.014935 0.0013 104 0.0061 205 0.0105 378 0.015036 0.0014 106 0.0062 208 0.010637 0.0015 108 0.0063 386 0.015138 0.0016 210 0.0107 392 0.0152214 0.0108 397 0.015340 0.0017 110 0.0064 217 0.010941 0.0018 112 0.0065 403 0.015442 0.0019 114
43、0.0066 220 0.0110 409 0.015543 0.0020 116 0.0067 223 0.0111 415 0.015645 0.0021 118 0.0068 226 0.011246 0.0022 119 0.0069 229 0.0114 421 0.015747 0.0023 427 0.015848 0.0024 122 0.0070 235 0.0115 433 0.0159124 0.0071 238 0.0116 439 0.016050 0.0025 126 0.007251 0.0026 128 0.0073 241 0.0117 446 0.01615
44、2 0.0027 245 0.0118 453 0.016254 0.0028 130 0.0074 249 0.0119 459 0.016355 0.0029 132 0.007556 0.0030 134 0.0076 252 0.0120 466 0.016458 0.0031 136 0.0077 255 0.0121 470 0.016559 0.0032 138 0.0078 258 0.0122263 0.012361 0.0033 140 0.0079 266 0.0124 480 0.016663 0.0034 142 0.0080 269 0.0125 487 0.016
45、764 0.0035 144 0.0081 493 0.016865 0.0036 146 0.0082 273 0.012666 0.0037 148 0.0083 277 0.0127 502 0.016968 0.0038 510 0.017069 0.0039 150 0.0084 280 0.0128 517 0.0171154 0.0085 285 0.012970 0.0040 156 0.0086 289 0.0130 521 0.017272 0.0041 158 0.0087 534 0.017374 0.0042 292 0.0131C539 84 (2016)3TABL
46、E 1 ContinuedTemperature,CAirCorrection, %Temperature,CAirCorrection, %Temperature,CAirCorrection, %Temperature,CAirCorrection, %75 0.0043 160 0.0088 296 0.0132 542 0.017476 0.0044 163 0.0089 551 0.017578 0.0045 165 0.0090 300 0.0133 559 0.0176168 0.0091 305 0.013480 0.0046 309 0.013582 0.0047 170 0
47、.0092 313 0.0136 568 0.017783 0.0048 173 0.0093 317 0.0137 578 0.0178587 0.0179 700 0.0190 840 0.0200 1000 0.0209596 0.0180 712 0.0191 850 0.0201606 0.0181 726 0.0192 870 0.0202 1020 0.0210615 0.0182740 0.0193 880 0.0203 1040 0.0211620 0.0183 752 0.0194635 0.0184 900 0.0204 1060 0.0212766 0.0195646
48、0.0185 920 0.0205 1080 0.0213657 0.0186 780 0.0196790 0.0197 940 0.0206 1100 0.0214668 0.0187679 0.0188 810 0.0198 960 0.0207690 0.0189 820 0.0199 980 0.0208AIf the starting temperature, t0, is above 20C, the entry in the table opposite that of the starting temperature should be subtracted from each
49、 of the succeeding corrections.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or
