1、Designation: C 455 07Standard Classification ofChrome, Chrome-Magnesia, Magnesia-Chrome, andMagnesia Brick1This standard is issued under the fixed designation C 455; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This classification categorizes machine-made refractorybrick defined as chrome, chrome-magnesia, magnesia-chrome,and magne
3、sia brick (see 3.1). It does not cover products madefrom electrically fused magnesium oxide or to products madeby fusion casting. Its purpose is to describe classes distin-guished by obvious differences in magnesium oxide (MgO)content except for chrome brick.1.2 This standard does not purport to add
4、ress 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-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:C71 Terminolog
5、y Relating to Refractories2NOTE 1Chemical analysis of refractory product is determined by acombination of x-ray fluorscence (XRF) and inductively coupled plasma(ICP) using standard reference materials (SRM), including various typesof minerals and refractory materials which are available from the Nat
6、ionalInstitute of Standards and Technology and other appropriate sources.3. Terminology3.1 For definitions of terms used in this classification, seeTerminology C71.4. Significance and Use4.1 This classification categorizes the defined types ofrefractory brick, with the exception of chrome brick, int
7、odistinct classes based on a nominal and minimal value formagnesium oxide content. Chrome brick are treated as aseparate class without reference to magnesium oxide content.Such classes have historically been generally useful in relatingthe defined types to specific industrial applications and indeve
8、loping product or purchasing specifications.5. Basis of Classification5.1 Chrome-magnesia, magnesia-chrome, and magnesiabrick are classified by MgO content as shown in Table 1.Chrome brick is not classified by MgO content (see Table 1).6. Test Methods6.1 The determination of MgO on an ignited basis
9、asrequired by this classification shall be determined by a com-bination of x-ray fluorescence (XRF) and inductively coupledplasma (ICP) using standard reference materials (SRM), in-cluding various types of minerals and refractory materialswhich are available from the National Institute of Standardsa
10、nd Technology and other appropriate sources.7. Retests7.1 Because of variables resulting from sampling and thelack of satisfactory reproducibility in tests conducted bydifferent laboratories, the material may be resampled andretested when requested by either the manufacturer or thepurchaser. This ma
11、y apply in instances when the first testresults do not conform to the requirements prescribed in thisclassification. The final results to be used shall be the averageof at least two sets of results, each of which has been obtainedby following in detail the specified testing procedures.8. Keywords8.1
12、 brick; chrome; classification; magnesium oxide; magne-sia; MgO; refractories1This classification is under the jurisdiction of ASTM Committee C08 onRefractories and is the direct responsibility of Subcommittee C08.92 on The JosephE. Kopanda Subcommittee for Editorial, Terminology and Classification.
13、Current edition approved March 1, 2007. Published April 2007. Originallyapproved in 1960. Last previous edition approved in 1999 as C 455 97 (1999).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandar
14、ds volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.ASTM International takes no position respecting the validity of any patent rights asserted in conn
15、ection 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 respons
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17、onsideration 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 copyrighted by ASTM International, 10
18、0 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-mail); or through the ASTM w
19、ebsite(www.astm.org).TABLE 1 Classification of Chrome,AChrome-Magnesia,Magnesia-Chrome, and Magnesia Brick According to MgOContentClass MgO Content, %BNominal MinimumChrome-Magnesia and Magnesia-Chrome BrickC30 30 2540 40 3550 50 4560 60 5570 70 6580 80 75Magnesia BrickC90 90 8695 95 9198 98 96AChrome bricka refractory brick, which may be burned or unburned,manufactured predominately or entirely of refractory-grade chrome ore.BIgnited basis.CThis classification applies to both chemically bonded and burned brick.C455072
