1、Designation: C544 03 (Reapproved 2017)Standard Test Method forHydration of Dead-Burned Magnesite or Periclase Grain1This standard is issued under the fixed designation C544; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、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 measurement of the relativeresistance of magnesia grain to hydration.1.2 This standard
3、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.1.3 This internat
4、ional 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) Comm
5、ittee.2. Referenced Documents2.1 ASTM Standards:2C92 Test Methods for Sieve Analysis and Water Content ofRefractory MaterialsC357 Test Method for Bulk Density of Granular RefractoryMaterialsC456 Test Method for Hydration Resistance of Basic Bricksand ShapesC493 Test Method for Bulk Density and Poros
6、ity of Granu-lar Refractory Materials by Mercury Displacement (Dis-continued 2002) (Withdrawn 2002)33. Significance and Use3.1 This test method determines relative hydration resis-tance of magnesia grain.3.2 This test method is used in industry to evaluate grainsamples and is used for specification
7、purposes in some cases.3.3 Care must be taken in interpreting the data.4. Apparatus4.1 Autoclave, suitable for operation at 80 psi (552 kPa) at324 F (162 C) and equipped with pressure and temperaturemeasuring devices and safety equipment.NOTE 1A suitable apparatus is shown in Fig. 1 of Test Method C
8、456.4.2 Standard Sieves, ASTM No. 6 (3.35 mm), No. 12(1.70 mm), No. 20 (850 m), No. 40 (425 m), and No. 50(300 m).NOTE 2The equivalent Tyler Standard Series sieves described in TestMethods C92 may be substituted for the ASTM sieves.5. Procedure5.1 Remove the material retained on a No. 6 (3.35-mm)sie
9、ve, and crush it to pass the No. 6 sieve to obtain themaximum amount of coarse material. Recombine with theportion passing the No. 6 sieve, and screen the resultant sampleto remove all material passing a No. 40 (425-m) sieve. Ifnecessary, dry at 220 to 230 F (105 to 110 C).5.2 Separate this sample i
10、nto the following three fractions:Passing Sieve No. Retained on Sieve No.6 (3.35 mm) 12 (1.70 mm)12 (1.70 mm) 20 (850 m)20 (850 m) 40 (425 m)5.3 Prepare a 100-g specimen by using equal parts byweight of the three sizes listed in 5.2.5.4 Add sufficient water to the autoclave to maintain 80 psi(552 kP
11、a) at 324 F (162 C) for the duration of each 5-h test,but not enough to permit contact with any of the specimens.5.5 Place each weighed specimen in a No. 3 porcelaincrucible, and cover with a loosely crimped piece of aluminumfoil to protect the specimen from drip or condensate. Dry thecovered crucib
12、les in a forced-air dryer at 220 to 230 F (105 to110 C) for at least 2 h.5.6 Place the preheated rack containing the specimens in theautoclave. Heat the autoclave with the pressure-release valveopen; after a steady flow of steam is obtained through thevalve, continue to purge for 3 min to remove all
13、 air, close thevalve, and bring the autoclave to 80 psi (552 kPa) at 324 F(162 C) in a total time of 1 h. Maintain the autoclave at 80 65 psi (552 6 35 kPa) and 324 6 4 F (162 6 2 C) for 5 h.1This test method is under the jurisdiction of ASTM Committee C08 onRefractories and is the direct responsibi
14、lity of Subcommittee C08.04 on ChemicalBehaviors.Current edition approved Nov. 1, 2017. Published November 2017. Originallyapproved in 1964. Last previous edition approved in 2013 as C544 03 (2013).DOI: 10.1520/C0544-03R17.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orconta
15、ct ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International, 100 Barr Harbor Drive, P
16、O Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued
17、by the World Trade Organization Technical Barriers to Trade (TBT) Committee.15.7 Allow sufficient cooling to lower the autoclave to 20 to30 psi (138 to 207 kPa) with the release valve closed, and thencarefully open the relief valve to reduce the autoclave toatmospheric pressure in a total time betwe
18、en 30 and 60 min.Remove the specimens and dry to constant weight at 220 to230 F (105 to 110 C) in a forced-air dryer. Record theindividual specimen weight, G.5.8 Place each specimen with the cover and the pan on a No.50 (300-m) sieve, and screen according to Test Methods C92for dry sieve analysis. W
19、eigh the amount of material retainedon the No. 50 sieve. Record the individual specimen weight, H.6. Calculation and Report6.1 Calculate the percentage hydration as follows:hydration, % 5 G 2 H!/G# 3100where:G = weight of dried specimen after hydration, g, andH = weight of hydrated specimen retained
20、 on a No. 50(300-m) sieve, g.6.2 Report the amount of hydration of each specimen as thepercentage of material passing the No. 50 (300-m) sieve afterthe hydration test.7. Precision and Bias7.1 Interlaboratory Study:7.1.1 An interlaboratory test program between six laborato-ries was conducted. Each la
21、boratory tested four magnesiamaterials. Each of the four magnesia materials was tested fourtimes. Typical chemical analyses and bulk specific gravity dataon the four magnesia materials appear in Table 1.47.1.2 No ruggedness test was run on this test method priorto conducting the interlaboratory stud
22、y.7.2 Precision:7.2.1 RepeatabilityThe maximum permissible differencedue to test error between two test results obtained by oneoperator on the same material is given by the repeatabilityinterval and the relative repeatability interval (coefficient ofvariation). The 95 % repeatability intervals are g
23、iven in Table2. Two test results that do not differ by more than therepeatability interval will be considered to be from the samepopulation, and, conversely, two test results that do differ bymore than the repeatability interval will be considered to befrom different populations.7.2.2 Reproducibilit
24、yThe maximum permissible differ-ence due to test error between two test results obtained by twooperators in different laboratories on the same type of materialusing the same type of test equipment is given by thereproducibility interval and relative reproducibility interval(coefficient of variation)
25、. The 95 % reproducibility intervalsare given in Table 2. Two test results that do not differ by morethan the reproducibility interval will be considered to be fromthe same population, and, conversely, two test results that dodiffer by more than the reproducibility interval will be consid-ered to be
26、 from different populations.7.3 BiasThis test method does not lend itself to a state-ment of bias.8. Keywords8.1 autoclave; grain; hydration resistance; magnesite; peri-clase; refractories4These data were not measured on the actual samples tested in the hydration test,but are representative of the m
27、aterials used in the interlaboratory study.TABLE 1 Material PropertiesMaterial Number 1234Chemical Analysis (CalcinedBasis), %:Silica (SiO2) 1.0 3.3 0.7 0.55Alumina (Al2O3) 0.5 1.7 0.2 0.2Iron Oxide (Fe2O3) 0.5 3.8 0.2 0.2Chromic Oxide (Cr2O3) . 2.2 . .Lime (CaO) 3.0 11.0 0.7 2.2Boron Oxide (B2O3) .
28、 . . . . . 0.03 0.01Magnesia (MgO) 95.0 78.0 98.2 96.75Total, % 100.0 100.0 100.0 99.9Bulk Specific Gravity:By Water Displacement(ASTM C357). . . . . . 3.21 3.32By Mercury Displacement(ASTM C493)3.36 3.15 3.27 3.37C544 03 (2017)2ASTM International takes no position respecting the validity of any pat
29、ent 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
30、 at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comm
31、ents will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighte
32、d by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-m
33、ail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 2 Repeatability and Reproducibility DataMaterialNumberAverage, XStandardWithin, SrDe
34、viationBetween, SRRepeatabilityInterval, rReproducibilityInterval, RCoefficient of VariationRelativeRepeatability,% rRelativeReproducibility,% RWithin Lab,VrBetween Labs,VR1 63.61 2.818 4.447 7.891 12.45 4.430 6.991 12.41 19.572 37.06 3.082 3.811 8.628 10.67 8.316 10.28 23.28 28.793 21.04 3.108 5.947 8.703 16.65 14.77 28.27 41.36 79.134 60.27 6.254 7.085 17.51 19.84 10.38 11.76 29.05 32.92C544 03 (2017)3
