1、Designation: C 1365 06Standard Test Method forDetermination of the Proportion of Phases in PortlandCement and Portland-Cement Clinker Using X-Ray PowderDiffraction Analysis1This standard is issued under the fixed designation C 1365; the number immediately following the designation indicates the year
2、 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 (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers direct determination of thepro
3、portion by mass of individual phases in portland cement orportland-cement clinker using quantitative X-ray (QXRD)analysis. The following phases are covered by this standard:alite (tricalcium silicate), belite (dicalcium silicate), aluminate(tricalcium aluminate), ferrite (tetracalcium aluminoferrite
4、),periclase (magnesium oxide), gypsum (calcium sulfate dihy-drate), bassanite (calcium sulfate hemihydrate), anhydrite (cal-cium sulfate), and calcite (calcium carbonate).1.2 This test method specifies certain general aspects of theanalytical procedure, but does not specify detailed aspects.Recommen
5、ded procedures are described, but not specified.Regardless of the procedure selected, the user shall demon-strate by analysis of certified reference materials (CRMs) thatthe particular analytical procedure selected for this purposequalifies (that is, provides acceptable precision and bias) (seeNote
6、1). The recommended procedures are ones used in theround-robin analyses to determine the precision levels of thistest method.NOTE 1Asimilar approach was used in the performance requirementsfor alternative methods for chemical analysis in Test Methods C114.1.3 The values stated in SI units shall be r
7、egarded as thestandard.1.4 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 establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior
8、 to use. For specifichazards, see Section 9.2. Referenced Documents2.1 ASTM Standards:2C114 Test Methods for Chemical Analysis of HydraulicCementC 150 Specification for Portland CementC 183 Practice for Sampling and the Amount of Testing ofHydraulic CementC 219 Terminology Relating to Hydraulic Ceme
9、ntC 670 Practice for Preparing Precision and Bias Statementsfor Test Methods for Construction MaterialsE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.
10、 Terminology3.1 Definitions are in accordance with Terminology C 219.3.2 Phases (1):33.2.1 alite, ntricalcium silicate (C3S)4modified in com-position and crystal structure by incorporation of foreign ions;occurs typically between 30 to 70 % (by mass) of the portland-cement clinker; and is normally e
11、ither the M1or M3crystalpolymorph, each of which is monoclinic.3.2.2 alkali sulfates, narcanite (K2SO4) may accommo-date Na+, Ca2+, and CO3in solid solution, aphthitalite (K4-x,Nax)SO4with x usually 1 but up to 3), calcium langbeinite(K2Ca2SO43) may occur in clinkers high in K2O, andthenardite (Na2S
12、O4) in clinkers with high Na/K ratios (1).3.2.3 aluminate, ntricalcium aluminate (C3A) modified incomposition and sometimes in crystal structure by incorpora-tion of a substantial proportion of foreign ions; occurs as 2 to15 % (by mass) of the portland-cement clinker; is normallycubic when relativel
13、y pure and orthorhombic or monoclinicwhen in solid solution with significant amounts of sodium (2).3.2.4 anhydrite, ncalcium sulfate CS! and is orthorhom-bic (see Note 2).NOTE 2Calcium sulfate is added to the clinker during grinding tocontrol setting time, strength development, and volume stability.
14、 Severalphases may form as a result of dehydration of gypsum. The first 1.51This test method is under the jurisdiction of ASTM Committee C01 on Cementand is the direct responsibility of Subcommittee C01.23 on CompositionalAnalysis.Current edition approved Dec. 15, 2006. Published January 2007. Origi
15、nallyapproved in 1998. Last previous edition approved in 2004 as C 1365 - 98 (2004).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 p
16、age onthe ASTM website.3The boldface numbers in parentheses refer to the list of references at the end ofthis standard.4When expressing chemical formulae,C=CaO,S=SiO2,A=Al2O3,F=Fe2O3,M = MgO, S =SO3,andH=H2O.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM Internatio
17、nal, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.molecules of water are lost between 0 and 65 C with minor changes instructure; and, above 95 C, the remaining 0.5 molecules of water are losttransforming the structure to the metastable g polymorph of anhydrite(
18、sometimes referred to as soluble anhydrite) and subsequently theorthorhombic form (3).3.2.5 bassanite, ncalcium sulfate hemihydrate CSH1/2!and is monoclinic.3.2.6 belite, ndicalcium silicate (C2S) modified in com-position and crystal structure by incorporation of foreign ions;occurs typically as 15
19、to 45 % (by mass) of the portland-cement clinker as normally the b polymorph, which is mono-clinic. In lesser amounts, other polymorphs can be present.3.2.7 calcite, ncalcium carbonate is trigonal and may bepresent in a cement as an addition or from carbonation of freelime.3.2.8 ferrite, ntetracalci
20、um aluminoferrite solid solutionof approximate composition C2(A,F) modified in compositionby variation in the Al/Fe ratio and by substantial incorporationof foreign ions as C4AXF2-Xwhere0x1.4; constituting 5to 15 % (by mass) of a portland-cement clinker; and isorthorhombic.3.2.9 free lime, nfree cal
21、cium oxide (C); cubic (see Note3).NOTE 3Free lime (CaO) may be present in clinker and cement butreadily hydrates to form portlandite (Ca(OH)2). Portlandite may carbonateto form calcium carbonate, generally as calcite. Heat-treating a freshly-ground sample to 600 C is useful to convert any portlandit
22、e back to freelime but will also dehydrate the hydrous calcium sulfate phases (gypsumand bassanite) to anhydrite.3.2.10 gypsum, ncalcium sulfate dihydrate CSH2! and ismonoclinic .3.2.11 periclase, nfree magnesium oxide (M); cubic.3.3 Definitions of Terms Specific to This Standard:3.3.1 Certified Ref
23、erence Material (CRM), na materialwhose properties (in this case phase abundance, XRD peakposition or intensity, or both) are known and certified (see Note4).NOTE 4NIST Standard Reference Material (SRMt) Clinkers 2686,2687, and 2688 are suitable CRMs for qualification.53.3.2 diffractometer, nthe ins
24、trument, an X-ray powderdiffractometer, for determining the X-ray diffraction pattern ofa crystalline powder.3.3.3 phase, na homogeneous, physically distinct, andmechanically separable portion of a material, identifiable by itschemical composition and crystal structure.3.3.3.1 DiscussionPhases in po
25、rtland-cement clinker andcements that are included in this test method are four majorphases (alite, belite, aluminate, and ferrite) and one minorphase (periclase).3.3.3.2 DiscussionPrecision values are provided for addi-tional phases (gypsum, bassanite, anhydrite, arcanite, andcalcite). Values for t
26、hese constituents may be provided usingthis method but are considered informational until suitablecertified reference materials for qualification are available.3.3.4 qualification, nprocess by which a QXRD proce-dure is shown to be valid.3.3.5 Rietveld analysis, nprocess of refining crystallo-graphi
27、c and instrument variables to minimize differencesbetween observed and calculated X-ray powder diffractionpatterns for one or more phases, estimating their relativeabundance.3.3.6 standardization, nprocess of determining the rela-tionship between XRD intensity and phase proportion for oneor more pha
28、ses (see Note 5).NOTE 5In the literature of X-ray powder diffraction analysis, thestandardization process has been commonly referred to as calibration;however, we have determined that standardization is a more accurate term.3.3.6.1 DiscussionRietveld analysis uses crystal structuremodels to calculat
29、e powder diffraction patterns of phases thatserve as the reference patterns. The pattern-fitting step seeksthe best-fit combination of selected pattern intensities to theraw data. The relative pattern intensities along with thecrystallographic attributes of each phase are used to calculaterelative a
30、bundance. The standardization approach uses pow-dered samples of pure phases to assess the relationship betweendiffraction intensity ratios and mass fraction ratios of two ormore constituents; and is referred to here as the traditionalmethod.3.3.7 X-ray diffraction (XRD), nthe process by whichX-rays
31、 are coherently scattered by electrons in a crystallinematerial.4. Background4.1 This test method assumes general knowledge concern-ing the composition of cement and portland-cement clinker.Necessary background information may be obtained from anumber of references (1, 4).4.2 This test method also a
32、ssumes general expertise in XRDand QXRD analysis. Important background information maybe obtained from a number of references (5-10).5. Summary5.1 This test method covers direct determination of theproportion by mass of individual phases in cement or portland-cement clinker using quantitative X-ray
33、powder diffractionanalysis. The following phases are covered by this standard:alite (tricalcium silicate, C3S), belite (dicalcium silicate C2S),aluminate (tricalcium aluminate, C3A), ferrite (tetracalciumaluminoferrite, C4AF), periclase (magnesium oxide, M), arcan-ite (potassium sulfate, KS!, gypsum
34、 (calcium sulfate dihy-drate, CSH2!, bassanite (calcium sulfate hemihydrate,CSH1/2!, anhydrite (calcium sulfate CS!, and calcite (cal-cium carbonate, CaCO3.A QXRD test procedure includes some or all of the follow-ing: (a) specimen preparation; (b) data collection and phaseidentification; (c) standar
35、dization (for the standardization ap-proach); (d) collecting a set of crystal structure models forrefinement (for the Rietveld approach); (e) use of an internal orexternal standard (to correct for various effects on intensitybesides phase proportion); (f) analysis of the sample (in whichthe powder d
36、iffraction pattern is measured and/or the intensity5Portland cement clinker SRMst from the Standard Reference MaterialProgram, National Institute of Standards and Technology.C1365062of selected XRD peaks or patterns are measured); and (g)calculation of the proportion of each phase.5.2 This test meth
37、od does not specify details of the QXRDtest procedure. The user must demonstrate by analysis ofcertified reference materials that the particular analytical pro-cedure selected for this purpose provides acceptable levels ofprecision and bias. Two recommended procedures (the Ri-etveld approach and the
38、 traditional approach used to determinethe acceptable levels of precision and bias) are given inAppendix X1 and Appendix X2.6. Significance and Use6.1 This test method allows direct determination of theproportion of some individual phases in cement or portland-cement clinker. Thus it provides an alt
39、ernative to the indirectestimation of phase proportion using the equations in Specifi-cation C 150 (Annex A1).6.2 This test method assumes that the operator is qualified tooperate an X-ray diffractometer and to interpret X-ray diffrac-tion spectra.6.3 This test method may be used as part of a qualit
40、y controlprogram in cement manufacturing.6.4 This test method may be used in predicting propertiesand performance of hydrated cement and concrete that are afunction of phase composition.6.5 QXRD provides a bulk analysis (that is, the weightedaverage composition of several grams of material). Therefo
41、re,results may not agree precisely with results of microscopicalmethods.7. Apparatus7.1 X-Ray DiffractometerThe X-ray diffractometer allowsmeasurement of the X-ray diffraction pattern from which thecrystalline phases within the sample may be qualitativelyidentified and the proportion of each phase m
42、ay be quantita-tively determined. X-ray diffractometers are manufacturedcommercially and a number of instruments are available. Thesuitability of the diffractometer for this test method shall beestablished using the qualification procedure outlined in thistest method.8. Materials8.1 Standardization
43、PhasesThe use of standardizationphases is recommended for establishing the intensity ratio/mass ratio relationships when using the traditional quantitativemethod. These phases must usually be synthesized (12, 13).8.2 CRM ClinkerThe use of three CRM clinkers isrequired to qualify the QXRD procedure.8
44、.3 Internal StandardThe use of an internal standard isrecommended for the standardization approach. Suitable ma-terials include chemical reagents (see 8.4) or CRMs (seeAppendix X1).8.4 Reagent ChemicalsReagent grade chemicals, if usedeither as an internal standard or during chemical extraction ofcer
45、tain phases, shall meet the specifications of the Committeeon Analytical Reagents of the American Chemical Societywhere such specifications are available.6Other grades may beused, provided it is first ascertained that the chemical issufficiently pure to permit its use without lessening the accu-racy
46、 of the determination.9. Hazards9.1 The importance of careful and safe operation of anX-ray diffractometer cannot be overemphasized. X-rays areparticularly hazardous. An X-ray diffractometer must be oper-ated safely to avoid serious injury or death. The X-rays aregenerated by high voltages, perhaps
47、as high as 55 kV peak,requiring care to avoid serious electric shock. Klug andAlexander (6) (pp. 5860) state, “The responsibility for safeoperation rests directly on the individual operator” (italics aretheirs).10. Sampling and Sample Preparation10.1 Take samples of cement in accordance with the app
48、li-cable provisions of Practice C 183. Take samples of portland-cement clinker so as to be representative of the material beingtested.10.2 Prepare samples as required for the specific analyticalprocedure (see Appendix X2).11. Qualification and Assessment11.1 Qualification of Test Procedure:11.1.1 Wh
49、en analytical data obtained in accordance withthis test method are required, any QXRD test procedure thatmeets the requirements described in this section may be used.11.1.2 Prior to use for analysis of cement or portland-cement clinker, qualify the QXRD test procedure for theanalysis. Maintain records that include a description of theQXRD procedure and the qualification data (or, if applicable,re-qualification data). Make these records available to thepurchaser if requested in the contract or order.11.1.3 If more than one X-ray diffra
