ASTM C583-2005(2009) Standard Test Method for Modulus of Rupture of Refractory Materials at Elevated Temperatures.pdf

1、Designation: C 583 05 (Reapproved 2009)Standard Test Method forModulus of Rupture of Refractory Materials at ElevatedTemperatures1This standard is issued under the fixed designation C 583; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revi

2、sion, 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 determination of the high-temperature modulus of rupture of refractory brick

3、 or mono-lithic refractories in an oxidizing atmosphere and under actionof a force or stress that is increased at a constant rate.1.2 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 establis

4、h appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E 220 Test Method for Calibration of Thermocouples byComparison Techniques3. Significance and Use3.1 Measuring the modulus of rupture of refra

5、ctories atelevated temperatures has become a widely accepted means toevaluate materials at service temperatures. Many consumercompanies have specifications based on this type of test.3.2 This test method is limited to furnaces operating underoxidizing conditions. However, with modifications for atmo

6、-sphere control in other test furnaces, the major criteria of thistest procedure may be employed without change.3.3 This test method is designed for progressive applicationof a force or stress on a specimen supported as a simple beamwith center-point loading. Test apparatus designed for theprogressi

7、ve application of a strain may yield different results,especially since refractory materials will reach a semiplasticstate at elevated temperatures where Hookes law does notapply, that is, stress is then not proportional to strain.3.4 This test method applies to fired dense refractory brickand shape

8、s, chemically bonded brick and shapes, shapesformed from castables, plastics, or ramming materials, and anyother refractory that can be formed to the required specimendimension.4. Apparatus4.1 Use either an electrically heated or gas-fired furnace(Note 1). A typical cross section of the furnace cont

9、aining thebearing edges is shown in Fig. 1. At least one pair of lowerbearing edges, made from volume-stable refractory material(Note 2), shall be installed in the furnace on 5-in. (127-mm)centers. A thrust column, containing the top bearing edge thatis made from volume-stable refractory material, s

10、hall extendoutside the furnace where means are provided for applying aload. The lower bearing edges and the bearing end of thesupport column shall have rounded bearing surfaces havingabout a14-in. (6-mm) radius (Note 3). The lower bearingsurfaces may be made adjustable, but must attain the standards

11、pan of 5 6332 in. (127 6 2 mm). The length of the lowerbearing surfaces shall exceed the specimen width by about14in. The load shall be applied to the upper bearing edge by anysuitable means. Instrumentation for measuring the load shall beaccurate to 1 %. The thrust column shall be maintained invert

12、ical alignment and all bearing surfaces parallel in bothhorizontal directions.NOTE 1The test furnace can be so constructed so that a number ofspecimens may be heated and tested at the same time. Bearing edges andloading devices may be provided for a number of individual specimens,but a more practica

13、l method is to provide means to move individualspecimens successively onto a single set of bearing edges for breaking.The use of a separate holding furnace for specimens to be transferred intothe test furnace for breaking is also satisfactory.NOTE 2A minimum of 90 % alumina content is recommended as

14、 asuitable refractory.NOTE 3All bearing surfaces should be checked periodically to main-tain a round surface.4.2 It is recommended that the furnace temperature becontrolled with calibrated platinum-rhodium/platinum thermo-couples connected to a program-controller recorder (see TestMethod E 220). Tem

15、perature differential within the furnace1This test method is under the jurisdiction of ASTM Committee C08 onRefractories and is the direct responsibility of Subcommittee C08.01 on Strength.Current edition approved Sept. 1, 2009. Published September 2009. Originallyapproved in 1965. Last previous edi

16、tion approved in 2005 as C 583 05.2For 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.1Copyright ASTM Internation

17、al, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.shall not be more than 620F (11C), but the controllingthermocouple shall be placed within12 in. (13 mm) of thegeometric center of a side face of the test specimen whenpositioned on the bearing edges.4.3 Furnace A

18、tmosphereAbove a furnace temperature of1470F (800C), the furnace atmosphere shall contain aminimum of 0.5 % oxygen with 0 % combustibles. Take theatmosphere sample from the furnace chamber proper, prefer-ably as near the test specimen as possible.5. Sampling5.1 The sample shall consist of five speci

19、mens, each takenfrom five brick or shapes or from test specimens made frommonolithic aggregate refractories.6. Test Specimen6.1 The standard test specimen shall be 1 6132 by 1 6132by approximately 6 in. (25 6 0.8 by 25 6 0.8 by approxi-mately 152 mm). Note in the report if other specimen sizes areus

20、ed. Specimens cut from brick shall have at least one originalbrick surface. If cut from shapes, the specimens shall be takenparallel to the longest dimension. For irregular shapes, all fourlong surfaces of the specimen may be cut faces. Note this in thereport.6.2 Opposite faces of the specimen shall

21、 be parallel, andadjacent faces shall be perpendicular.6.3 Measure the width and depth of the test specimen atmid-span to the nearest 0.01 in. (0.3 mm).7. Procedure7.1 Set the specimens in either the test or holding furnacewithout an applied load, and heat to the test temperature usingthe following

22、schedule:7.1.1 Burned Refractory ProductsThe rate of heatingfrom room temperature shall not exceed 600F (330C)/h to1800F (980C), and shall not exceed 200F (110C)/h from1800F to the test temperature (Note 4). Maintain the testtemperature for a minimum of3h(Note 5).NOTE 4Heating at 600F (330C)/h can i

23、nitiate thermal shock insome brick. A maximum heating rate of 150F (83C)/h is recommendedfor materials sensitive to thermal shock.NOTE 5Maintaining specimens at test temperature for 3 h before loadapplication is adequate for most compositions and temperatures ofinterest. However, there may be certai

24、n compositions and temperaturesrequiring additional holding time at temperature in order to obtainconsistent results. Experience and use of the test procedure will aid indetermining when exploratory testing is required to arrive at the holdingtime necessary. If departure is made from the specified m

25、inimum time, theholding time used will be included in the report of the results.7.1.2 Unburned or Chemically Bonded RefractoryProductsThe rate of heating from room temperature shall be600F (330C)/h to 1800F (980C), and 200F (110C)/hfrom 1800F to the test temperature. Maintain the test tem-perature f

26、or a minimum of 12 h.7.2 Following the holding period, move the specimen to thesupporting bearing edges. When possible, an original face ofthe specimen shall be used for the tension face, that is, the facein contact with the two lower bearing edges. Apply the loadparallel to the direction (if known)

27、 of pressing of the specimen.7.3 Control test temperature by the thermocouple that islocated within12 in. (13 mm) of the geometric center of a sideface of the specimen when it is in position for testing. Holdspecimen in testing position 10 min before testing (Note 6).Temperature shall not vary more

28、than minus 0 plus 20F(11C) from the specified test temperature.NOTE 6This hold period may be shortened for continuously chargedfurnaces.7.4 Test temperatures are not specified but must be agreedupon between laboratories and must be included in the report.FIG. 1 Cross Section of Typical Apparatus (He

29、ating Means Not Shown)C 583 05 (2009)2Test temperatures should be selected in even 100F (55C)intervals, but if agreed, other multiples could be used.7.5 Bring the top bearing edge to bear at mid-span on thespecimen, ensure proper alignment of bearing surfaces, andapply pressure through the loading m

30、echanism until failure ofthe specimen occurs. The rate of application of the load on thespecimen shall be 175 6 17.5 lbf (778 6 77.8 N)/min. Theresulting rate of increase in bending stress for the standard 1 by1 by 6-in. (25 by 25 by 152-mm) specimen is 1312.5 6 131 psi(9.05 6 0.9 MPa)/min.3If non-s

31、tandard specimens are used,the proper loading rate should be determined from the forego-ing stressing rate and full details disclosed in the report.7.6 Move the other specimens successfully onto the bearingedges and break them in accordance with the precedingprocedure.8. Calculation8.1 Calculate the

32、 modulus of rupture (MOR) for eachrectangular specimen as follows:MOR 5 3PL/2bd2(1)where:MOR = modulus of rupture, psi or MPa,P = concentrated load at rupture, lbf or N,L = span between supports, in. or mm,b = breadth or width of specimen, in. or mm, andd = depth of specimen, in. or mm.9. Report9.1

33、Report the test temperature, the five individual testresults, and the average modulus of rupture and standarddeviation in lbf/in.2(or MPa for the five specimens.9.2 Also, list in the report any deviations from standard testrequirements such as specimen size, span, heating rate, soaktime, or loading

34、rate.10. Precision and Bias10.1 Ruggedness tests conducted in 1977 showed that themost sensitive variables were specimen dimensions, test tem-perature, and soak time. Of smaller influence were heating rateabove 1800F (980C) and loading rate. Test results areincorporated in the method.10.2 Interlabor

35、atory Test DataThe results of interlabora-tory studies conducted in 1963 and in 1970 were used in 1979to revise the precision statements in accordance with latestrecommendations from ASTM Committee E11.10.2.1 In the 1963 study, four types of direct-bonded (fired)magnesite-chrome brick and two types

36、of chemically-bondedmagnesite-chrome brick were tested at 1800F (980C) and2300F (1260C). Five laboratories tested five specimens ofeach brick at each test temperature. In the 1970 study, twotypes of direct-bonded chrome brick, one 95 % MgO firedpericlase brick (BOF type), and one 90 % alumina brick

37、weretested at 2700F (1480C) by four laboratories using twentyspecimens of each type of brick.10.2.2 The precision was found to vary with the type ofbrick tested and also with the test temperature. Generally thestandard deviation was proportional to the strength level, andrelative precision is given

38、in terms of the average coefficientsof variation for each brick type and test temperature. However,in the case of fired brick, the relative precision tends toimprove with the level of strength.10.3 PrecisionFor two averages of five specimens testedwithin one laboratory, their difference is considere

39、d significantfor a probability of 95 % and t = 1.96 if it equals or exceedsthe repeatability interval for the applicable brick type in Table1. Likewise, the difference between two averages obtained bytwo laboratories is considered significant if it equals or exceedsthe applicable reproducibility int

40、erval in Table 1.10.4 BiasNo justifiable statement of bias is possiblebecause the true value of hot modulus of rupture cannot beestablished.11. Keywords11.1 compressive load; deformation resistance; flexuralstrength; high temperature; modulus of rupture; monolithicrefractories; refractory brick3This

41、 rate is 0.151 MPa/s, which is in agreement with the stress rate in PRERecommendation R 18, “Determination of the Hot Modulus of Rupture of Shapedand Unshaped Dense and Insulating Refractory Products”, 1978. Copies of PREstandards are available from the PRE Secretary, Lowenstrasse 31, P.O. Box 3361,

42、CH-8023 Zurich, Switzerland.C 583 05 (2009)3ASTM 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

43、 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 withdrawn. Your comments are invited either for revisio

44、n of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments 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 sho

45、uldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted 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 obta

46、ined by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).TABLE 1 Relative PrecisionBrick TypeTest Temperature Average MOR Coefficient of VariationRepeatabilityInterval, % ofAverageAReproducibili

47、tyInterval, % ofAverageAF C psi MPaWithinLabs, %BetweenLabs, %Chem-bond 1800 980 360 2.48 14.2 13.5 17.6 41.2Chem-bond 2300 1260 332 2.29 7.7 13.6 9.4 39.1Direct-bond 1800 980 1530 10.55 15.7 17.4 19.4 52.9Direct-bond 2300 1260 1208 8.33 17.9 15.3 22.2 47.9Direct-bond 2700 1480 708 4.88 32.3 29.8 40.0 91.7Periclase 2700 1480 1302 8.98 21.0 16.2 26.4 52.0Alumina 2700 1480 1836 12.66 17.6 10.4 21.8 36.1ABased on five specimens.C 583 05 (2009)4