1、Designation: D6915 12Standard Practice forCarbon BlackEvaluation of Standard Reference Blacks1This standard is issued under the fixed designation D6915; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A n
2、umber in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers guidelines for the production andtesting for uniformity of a set of carbon blacks to be used asStandard Reference B
3、lacks (SRBs).1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 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
4、establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1510 Test Method for Carbon BlackIodine AdsorptionNumberD2414 Test Method for Carbon BlackOil AbsorptionNumber (OAN)D3265 Test Method
5、 for Carbon BlackTint StrengthD3493 Test Method for Carbon BlackOil AbsorptionNumber of Compressed Sample (COAN)D4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustriesD4821 Guide for Carbon BlackValidation of Test MethodPrecision and Bi
6、asD6556 Test Method for Carbon BlackTotal and ExternalSurface Area by Nitrogen Adsorption3. Significance and Use3.1 This practice is intended to ensure that SRBs areproduced and evaluated by a standard procedure.3.2 This practice is to be used to establish the averagephysicochemical properties of a
7、set of carbon blacks to be usedas SRBs.3.3 The carbon black grades to be used as SRBs should beselected to give as much coverage of the typical usage rangefor each test and as nearly evenly spaced across the range aspossible. Typically, the carbon black grades selected consist ofthree tread (hard) t
8、ype furnace grades (designatedA, B, and C),three carcass (soft) type furnace grades (designated D, E, andF), and one thermal type grade (designated G). SubcommitteeD24.61 may elect to carry one or more of the existing SRBsinto the next set provided there is enough remaining material atthe rate of us
9、age to last through the expected life of the nextset. Limiting the choice of grades to be used means that not alltests will have an SRB set that is evenly spaced across therange of interest. All the SRB candidates are produced atapproximately the same time by the various producers. Theyare used as a
10、 set once they are approved. The sets areconsecutively numbered. Values and identification for thecurrent set are given in Guide D4821. Any SRBs carriedforward will be renumbered for the new set.4. Production, Packaging, Quality Control, and QualityAssurance4.1 It is assumed that manufacturers of th
11、e SRBs will usestate-of-the-art techniques to ensure maximum uniformitythroughout the entire production run. The production should bemade in one continuous production and packaging lot run. Thetesting called for in this practice is not intended to be asubstitute for in-process quality control. This
12、interlaboratorystudy is only adequate to verify the quality of a homogeneouslot.4.2 The size of the lot for each SRB is determined byhistorical records on the rate of use. The lot should have anexpected life of about five years at the most recent rate of use.Historically, the lot size has usually be
13、en 10 000 lb.4.2.1 The actual usage rate of any reference material mayresult in one or more SRB material being depleted before theremaining materials in a given SRB set. When this happens,Subcommittee D24.61 may elect to have a supplemental lotproduced for the needed SRB(s).4.2.2 It is preferred tha
14、t any supplemental SRB lots beproduced at the same location, on the same production equip-ment, under the same production conditions as reasonably1This practice is under the jurisdiction of ASTM Committee D24 on CarbonBlack and is the direct responsibility of Subcommittee D24.61 on Carbon BlackSampl
15、ing and Statistical Analysis.Current edition approved June 1, 2012. Published August 2012. Originallyapproved in 2003. Last previous edition approved in 2007 as D6915 07. DOI:10.1520/D6915-12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at ser
16、viceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1possible, and using the same production targets and spe
17、cifica-tions as was used to produce the initial SRB lot in order tominimize variation between the two lots.4.2.3 The supplemental lot size must be large enough tomeet the expected life of the remaining materials in the SRBset and without a prohibitively large quantity remaining fordisposal after the
18、 remainder of the set is depleted. Multiples oftypical pallet quantities of 1134 kg (2500 lb) are preferred. Thetotal quantity produced must be enough to meet the neededsupplemental lot size and have sufficient material to flush thepackaging equipment as described in 5.4.4.2.4 The supplemental SRB l
19、ot shall carry the same refer-ence designation as the SRB material it is replacing with theaddition of another digit numbering the lot, beginning with thedigit “2”. For example, a supplemental lot for the referencematerial SRB8A would be designated SRB8A2. If the condi-tions of 4.2.3 are met, there
20、will not be a need for anothersupplemental lot of any given SRB material.4.3 The SRB material should be bagged in 22.7 kg (50-lb)polyethylene bags to reduce moisture incursion. Each palletshould have a nominal 50 bags. Each pallet of bagged materialshould be wrapped in plastic to reduce environmenta
21、l expo-sure.5. Uniformity Sampling and Testing5.1 It is the producers responsibility to ensure the SRB isproduced under stable conditions using good statistical processcontrol techniques. Such control techniques include but are notlimited to:5.1.1 Stable statistical process control for at least 24 h
22、 priorto isolating the candidate SRB material.5.1.2 Stable statistical process control during the entireperiod the candidate SRB material is being produced. If thereis an occurrence of instability (process not in statistical control)while the candidate SRB material is being produced, theisolated mat
23、erial must be discarded and a new period ofstability demonstrated per 5.1.1.5.1.3 The storage vessel used to hold the candidate SRBmaterial must be emptied and reasonably cleaned prior to beingused to isolate the candidate SRB material. The emptying andcleaning is particularly important if the stora
24、ge previously helda material of a different grade than the candidate SRB material.5.2 The producer shall maintain all test equipment in propercalibration and be able to supply proof of calibration records,if requested. It is preferred that the testing laboratory for theproduction facility be an acti
25、ve participant in D24s LaboratoryProficiency Rating System (LPRS) program. Active participa-tion shall be demonstrated by submitting test results for at leastthe previous three LPRS samples.5.3 The producer of the SRB shall be responsible forperforming all testing to demonstrate lot uniformity, and
26、theproducer must submit the uniformity data to subcommitteeD24.61. The tests to be performed as a minimum are thoselisted in Section 6. All test results must be 62 repeatabilitystandard deviations as determined for each test using any oneof the following means of determining Sr:(1) Any appropriate S
27、RB materials Srlisted in the preci-sion table for a given test.(2) The average pooled value Srlisted in the precision tablefor a given test.(3) Determine a tests Srusing a linear regression fromexisting precision data for a given test as defined in Annex A1.5.4 The packaging equipment used to packag
28、e the SRB lotmust be flushed to remove any possible contamination fromother materials that may remain in the packaging system. Thisflushing shall be accomplished by packaging at least 10 000 kg(22 000 lb) of the SRB material before isolating the packagesto be used for the SRB lot. This flushing is e
29、specially criticalif the same packaging equipment is used to package othergrades of carbon black.5.5 The samples for determining lot uniformity shall betaken at the same time as when the SRB is packaged. Thenumber of samples and sampling location needed to demon-strate uniformity shall be:5.5.1 Typi
30、cally a bag is removed from the packaging streamat the designated sample location without reducing the totalbag count on the pallet (nominally 50) so that the total numberof bags pulled is the sum of bags on the pallet and bags neededfor samples. It may be necessary to remove more than one bagat eac
31、h sampling event to provide a sufficient quantity forsubsequent uniformity testing per 5.6.5.5.2 If just one pallet of material is being packaged, take asample at the beginning (bottom layer), middle, and end (toplayer) of the pallet.5.5.3 If more than one pallet of material is being packaged,take a
32、 sample at the beginning (bottom layer) and middle ofeach pallet and the end (top layer) of the last pallet.5.6 The number of samples taken and the quantity collectedfor each sample shall be adequate to perform all uniformitytesting and have sufficient material, such that when all samplematerial is
33、combined and blended, there will be enoughmaterial that all the laboratories participating in the determi-nation of the mean and control limit testing can perform the testprotocol and have material left if additional testing is subse-quently needed.6. Procedure6.1 Each laboratory will use the curren
34、t SRBs to verify thatall test methods are in calibration.6.2 Each sample is tested once on each of two days by twodifferent technicians (total of four test results).6.3 Physicochemical Tests:6.3.1 Perform the following physicochemical tests on thenew SRB (this does not apply to the testing of the He
35、at Treated(HT) SRBs):6.3.1.1 Iodine Adsorption Number (Test Method D1510)Report the result obtained from an individual determination ingrams of iodine per kilogram to the nearest 0.1 unit.6.3.1.2 Multipoint B.E.T. NSA (Test Method D6556)Report a single determination in 103m2/kg (m2/g) to thenearest
36、0.1 unit.D6915 1226.3.1.3 Oil Absorption Number (Test Method D2414)Report the result obtained from an individual determination in10-5m3/kg (cm3/100 g) to the nearest 0.1 unit.NOTE 1Each participating laboratory must ensure that the absorptom-eter has been properly calibrated. Reported OAN values mus
37、t be regressedto the previous SRB set.6.3.1.4 Oil Absorption Number of Compressed Sample (TestMethod D3493)Report the result obtained from an individualdetermination in 10-5m3/kg (cm3/100 g) to the nearest 0.1 unit.NOTE 2Each participating laboratory must ensure that the absorptom-eter has been prop
38、erly calibrated. Reported COAN values must beregressed to the previous SRB set.6.3.1.5 Tint Strength (Test Method D3265)Report theresult obtained from an individual determination in percent ofITRB to the nearest 0.1 unit.6.3.1.6 Statistical Thickness Surface Area (STSA) (TestMethod D6556)Report sing
39、le determination in 103m2/kg(m2/g) to the nearest 0.1 unit.6.4 For the HT SRBs, perform the Iodine AdsorptionNumber Test (Test Method D1510). Report the result obtainedfrom an individual determination in grams of iodine perkilogram to the nearest 0.1 unit.7. Statistical Analysis7.1 The uniformity sa
40、mple material collected by the pro-ducer shall be blended, apportioned, and sent to each partici-pant in the interlaboratory study to evaluate the new SRB.7.2 To achieve statistical validity and allow for the removalof outliers, at least 20 laboratories should participate in theevaluation for each t
41、est method.7.3 Each participating laboratory shall maintain all testequipment in proper calibration and be able to supply proof ofcalibration and calibration records, if requested.7.4 The interlaboratory study protocol shall be determinedby subcommittee D24.61 prior to the production of the SRB(s).7
42、.5 The mean and control limit values of the SRBs for eachtest shall be determined using the methodology of PracticeD4483, including the removal of outlier values.7.6 When calibration data is collected along with the testresults for a new SRB and an analysis of the calibration datashows that any give
43、n laboratory is not in a state of calibration,the data from that laboratory may be removed from the data seteven though the data is not flagged as being an outlier by thetechniques of Practice D4483.7.7 After eliminating the outliers and any laboratories not ina state of calibration, the remaining d
44、ata for each test methodwill be used to provide mean and control limit values fortabulation in Guide D4821. This information may also beplaced in each test method, if desired. The analysis could beused to develop new precision and bias values for each testmethod.8. Acceptance8.1 Subcommittee D24.61
45、may reject all or part of acandidate SRB lot as not uniform. All SRB lots tested ashomogeneous by this practice will be considered acceptable byCommittee D24 for use as a new SRB. The mean values andcontrol limits will be published in Guide D4821.9. Shelf Life9.1 The shelf life of the Standard Refer
46、ence Black (SRB)carbon blacks is indefinite when properly stored in a mannerthat protects it from exposure to sources of moisture, such asprecipitation, other sources of liquid water, or high humidityenvironments. Iodine number is the only property known tochange over an extended period (years). Thi
47、s is due to a slowincrease in the oxygen content and is primarily observed withtread blacks and other high surface area carbon blacks. Stepsare being taken within ASTM Committee D24 to developstandards that are more stable over a long period.10. Keywords10.1 blending; lot size; physical properties;
48、physicochemi-cal properties; shelf life; standard reference blacks (SRBs)ANNEXA1. DETERMINATION OF SrUSING LINEAR REGRESSIONA1.1 An appropriate Srlevel can be determined using aregression analysis of mean level and Srvalues found in theprecision table for a given test. The regression may beperformed
49、 using all six furnace SRBs, or, if more appropriate,using the three tread (hard) blacks or three carcass (soft) blacksas demonstrated in Fig.A1.1. The regression coefficients (slopeand intercept) are then used to estimate an Srfor a materialsmean level as shown in Fig.A1.2 and TableA1.1. The exampleis a tread or hard black with an STSA mean level of 160 m2/gand an estimated Srof 1.65 m2/g.D6915 123ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this stand
