1、Designation: C 1356 07Standard Test Method forQuantitative Determination of Phases in Portland CementClinker by Microscopical Point-Count Procedure1This standard is issued under the fixed designation C 1356; the number immediately following the designation indicates the year oforiginal adoption or,
2、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 a systematic procedure formeasuring the percentage volu
3、me of the phases in portlandcement clinker by microscopy.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 establish appro-priate safety and health practices and determine the applica-bili
4、ty of regulatory limitations prior to use.1.3 The values stated in SI units are to be regarded as thestandard.2. Referenced Documents2.1 ASTM Standards:2C 150 Specification for Portland CementC 219 Terminology Relating to Hydraulic CementC 670 Practice for Preparing Precision and Bias Statementsfor
5、Test Methods for Construction MaterialsD75 Practice for Sampling AggregatesD 3665 Practice for Random Sampling of ConstructionMaterials3. Terminology3.1 Definitions:3.1.1 clinker phase, na physically and chemically distinctoptically identifiable portion of the clinker sample, includingboth principal
6、 phases (alite, belite, aluminate, and ferrite),minor phases (for example, free lime, periclase, and alkalisulfates), and voids.3.1.1.1 DiscussionVoids, though not a phase in the senseof being a crystalline compound, are a distinct, identifiableportion of a clinker microstructure.3.1.2 voids, nisola
7、ted or interconnected open areas in theclinker, also called pores.3.2 Principal Clinker Phases:33.2.1 alite, ncrystalline tricalcium silicate (C3S), modifiedin composition and crystal structure by incorporation of foreignions; the crystals are pseudo-hexagonal with well-definedfaces, though less reg
8、ular shapes commonly occur.3.2.2 aluminate, ntricalcium aluminate (C3A) modified incomposition and crystal structure by incorporation of a sub-stantial proportion of foreign ions; aluminate forms cubiccrystals when relatively pure, and forms identifiable elongatedcrystals commonly called “alkali alu
9、minate” when in solidsolution with significant amounts of potassium or sodium, orboth.3.2.3 belite, ncrystalline dicalcium silicate (C2S), modi-fied in composition and crystal structure by incorporation offoreign ions; belite usually occurs as rounded crystals markedby striations formed by cross sec
10、tions of lamellae, and mayoccur as single crystals or in clusters.3.2.4 ferrite, na solid solution of approximate composi-tion tetracalcium aluminoferrite (C4AF) modified in composi-tion by variation in the Al/Fe ratio and by substantial incorpo-ration of foreign ions; ferrite is characterized by hi
11、ghreflectivity in polished sections and is normally the onlystrongly colored compound among the principal clinkerphases.3.2.4.1 DiscussionAluminate and ferrite form most of theinterstitial material between the silicate crystals and, undercertain conditions of cooling, may not be easily identifiable
12、orresolved by ordinary light microscopy.3.3 Minor Clinker Phases:3.3.1 alkali sulfates, nsodium sulfate, potassium sulfate,and double sulfates such as calcium langbeinite(K2SO42CaSO4).3.3.2 free lime, ncalcium oxide (C) found mostly as roundcrystals.3.3.3 periclase, ncrystalline form of free magnesi
13、umoxide (M), that has not been taken up in solid solution withother phases.3.4 For definitions of other terms relating to hydrauliccements, refer to Terminology C 219.1This test method is under the jurisdiction of ASTM Committee C01 on Cementand is the direct responsibility of Subcommittee C01.23 on
14、 CompositionalAnalysis.Current edition approved June 1, 2007. Published July 2007. Originally approvedin 1996. Last previous edition approved in 2001 as C 1356 96(2001).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annua
15、l Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3C = CaO, S = SiO2,A=Al2O3,F=Fe2O3,S=SO3, M = MgO, N = Na2O,and K = K2O in cement chemistry notation.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM Internati
16、onal, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Summary of Test Method4.1 The test method consists of the preparation and micro-scopical examination of a specimen produced by encapsulatingclinker in a mounting medium and sectioning the specimen soas to ex
17、pose the interior of particles for visual examination.Polishing the section surface and treating it with etchants tohighlight specific phases complete the preparation. Duringmicroscopical examination phases are identified and theirproportions determined by a point-count procedure. In thisprocedure,
18、the specimen is moved in uniform increments on amicroscope stage, and phases falling under the cross hairs ofthe eyepiece are identified and counted (1-5).5. Significance and Use5.1 This test method provides a relatively simple andreliable microscopical means of measuring the phase abun-dance of por
19、tland cement clinker (Note 1). Microscopical pointcounting provides a direct measure of the clinker phasecomposition in contrast to the calculated Bogue phase compo-sition (Note 2).NOTE 1This test method utilizes a reflected light microscope. Relatedmethods such as transmitted light microscopy, scan
20、ning electron micros-copy, and automated imaging techniques may also be used for clinkeranalysis but are not presently included in this test method.NOTE 2This test method allows direct determination of the proportionof each individual phase in portland-cement clinker. This test method isintended to
21、provide an alternative to the indirect estimation of phaseproportion using the equations in Specification C 150 (footnote C in Tablenumber 1 and footnote B in Table number 2).5.2 This test method assumes the operator is qualified tooperate a reflected light microscope and the required accesso-ries,
22、is able to correctly prepare polished sections and usenecessary etchants, and is able to correctly identify the con-stituent phases.5.3 This test method may be used as part of a quality controlprogram in cement manufacturing as well as a troubleshootingtool. Microscopic characterization of clinker p
23、hases may alsoaid in correlating cement properties and cement performance inconcrete, to the extent that properties and performance are afunction of phase composition.6. Apparatus6.1 Reflected light microscope.6.2 Mechanical stage with stepping increments rangingfrom 0.05 to 2.0 mm (to enable analys
24、is of clinkers of differentaverage crystal sizes) and vernier scales graduated in both Xand Y directions.6.3 Microscope objectives of magnification 53,103,203,and 403 or other magnifications suitable for the task.NOTE 3The use of reflected light with oil immersion is optional. It ishighly recommende
25、d for study of finely crystalline aluminate and ferritewhich typically form the ground mass in which the silicates occur.Reflected light objective lenses with magnification up to 1003 designedfor use in oil-immersion are required.6.4 Assorted eyepieces (53,103,203) which when com-bined with the obje
26、ctives described in 6.3 will provide magni-fications up to 8003.6.5 Eyepiece reticles (graticulae) with a linear grid patterncontaining 9, 16, or 25 intersections.6.6 Eyepiece micrometer for measuring dimensions of theobject under investigation and calibrated for each magnifica-tion.6.7 Stage microm
27、eter for the calibration of the eyepiecemicrometer.6.8 Light source that provides uniform and consistent illu-mination of the field and light of constant intensity.6.9 Counting (tallying) device capable of recording up toten categories of data.6.10 Crushing device capable of reducing sample particle
28、size to between 1 and 4 mm.6.11 Riffle sample splitter to reduce sample from initialvolume to approximately 100 g.6.12 Wire cloth sieves with openings suitable for sieving theentire clinker sample to broadly define the model size class,and sieves with 1-mm and 4-mm square openings to concen-trate pa
29、rticles of recommended size for specimen preparation.6.13 Vacuum impregnation device to force epoxy intoclinker voids. (Vacuum bell jar or desiccator connected to avacuum pump.)6.14 Curing oven, hot plate, slide warmer, or ultravioletlight may be used to accelerate the epoxy hardening.6.15 Thin, dia
30、mond-rimmed wafering saw for sectioningthe encapsulated clinker.6.16 Glass grinding (lapping) plates (300 mm 3 300mm 3 5 mm) required only if the mechanical system is notequipped to handle the final grinding with alumina powder.6.17 Ultrasonic cleaning device (optional) to clean thesample prior to,
31、between, and after polishing steps.7. Reagents and Materials7.1 Consumable grinding (lapping) and polishing supplies.After the encapsulated specimen has been cut with the saw, allor most of the following grinding and polishing steps arerequired: 120-, 320-, and 600-grit silicon carbide grindingpaper
32、s or equivalent and 5 m, 0.3 m, and 0.05 m aluminapolishing powders or their equivalent. Diamond grinding discs,silicon carbide paper, or polishing cloths and alumina polishingpowder may be used. Various types of polishing cloths may beused to produce a nearly flat clinker surface or a relief surfac
33、eto aid in identification of periclase (1).47.2 Sample cups (with volumes ranging from 10 to 20 mL)to contain epoxy-clinker mix during hardening.7.3 Epoxy resin and hardener for encapsulation of theclinker. Low viscosity resin will facilitate penetration intoclinker voids. When hardened it should ha
34、ve an abrasiveresistance close to that of the clinker to minimize relief duringpolishing. It should be resistant to substances used for washingand etching.7.4 Isopropyl alcohol (2-propanol) for washing the speci-men and for use in the ultrasonic cleaner. Propylene glycol issuitable as a lubricant fo
35、r the saw blade.7.5 Immersion oil with an index of refraction of 1.51 ifreflected light immersion-oil technique is used.4The boldface numbers in parentheses refer to the list of references at the end ofthis standard.C13560727.6 Etching material to highlight different phases for count-ing. (See Appen
36、dix X3.)8. Sampling8.1 Take samples of portland-cement clinker in accordancewith the applicable provisions of Practices D 75 and D 3665 soas to be representative of the quantity of material with whichtesting is concerned (see Appendix X1).8.2 Sieve the initial sample to obtain clinker particlesrepre
37、senting approximately 70 % of the clinker particle sizedistribution, centered about the mode. This particle size inter-val represents a size range of approximately two standarddeviations, one on each side of the mode, and is herein definedas the “bulk mode” (Mb), the combined material between theext
38、remes of the particle size distribution. State the sieve sizesused. If either extreme of the particle size distribution is to bestudied, the selected portion shall be identified as non-modal,and the percentages retained or passing standard sieves shall bestated. The recommended size fraction for mic
39、roscopicalanalysis is 2 to 4 mm. Therefore, that portion of the initialclinker sample representing the bulk mode shall be crushed,sieved, and riffled to provide approximately 100 g. Wholeclinkers may be encapsulated to study the phase distributionwithin clinker nodules.9. Preparation of Sample Speci
40、men9.1 Polished sections shall be polished to a fineness suchthat grinding pits and scratches have been eliminated (seeAppendix X1).9.2 Etching of the clinker surface may be used to facilitateidentification of clinker phases (1); additional information maybe found in the Appendix X1.10. Counting Pro
41、cedure10.1 Choose the microscope magnification such that adja-cent reticle grid points do not fall on the same crystal, exceptfor a few unusually large crystals. Magnification from 2003 to5003 will accommodate most clinkers. Reticles with multiplegrid points are recommended. Single crosshair reticle
42、s are notsuitable.10.2 Choose the stepping interval such that an entirelydifferent field of view is observed after each step.10.3 Attach a mechanical stage to the microscope. Themechanical stage may be an electrically driven specimencarriage connected to an automatic electronic counter or asimple ha
43、nd-operated carriage and counter. Place a smallamount of soft modeling clay on a standard, petrographic glassslide (27 mm 3 46 mm) and level the sample thereon. Eitheruse a commercial leveling device or use a small spirit level toadjust the mount while pressing it firmly into the clay. A tissuepaper
44、 between the polished section and the leveling device orspirit level prevents surface scratches. Place the glass slidewith attached clay and leveled mount on the mechanical stage.Check the accuracy of leveling by observing the focus atseveral points on the polished surface. Move to a starting point(
45、the initial field of view from which data will be taken) at theedge of the mount and record the position in the X-Ycoordinate system, using the graduated scales on the mechani-cal stage.10.4 Use a tally sheet or a counting device to record thephases as required. The observer should not keep a mental
46、 tallyof any data because of possible bias. Identify and record eachphase under the grid intersections. In some cases, the aluminateand ferrite quantities may be combined and labeled “matrix”.Move the mechanical stage a distance of one stepping intervalin the chosen X or Y direction to bring another
47、 field into view.The phases under the grid points are identified, counted, andthe mechanical stage advanced one stepping interval to anadjacent field of view. This procedure is continued until a rangeof 3000-4000 points are recorded.At the clinker periphery, some of the reticle points may fallon the
48、 encapsulating epoxy that surrounds the clinker particle.Count only points within the clinker, and disregard the reticlepoints over epoxy at the clinker periphery. Thus, the clinkervoid space (porosity), if determined in the point count, does notinclude cavities on the surface of the clinker particl
49、e. As onesteps over irrelevant areas (such as epoxy exterior to the clinkeror severally damaged portions of the polished surface thatobscure the phase identification) the count is temporarilysuspended until a suitable clinker surface again falls under thereticle grid points. Artifacts (for example, blot marks, residualliquids) on the section surface are not to be counted. If theidentity of the phase is obscured by the area formed by the gridintersection, one should consistently use a specified corner ofthe intersection where the phase can be clearly observed.When th
