1、Designation: D1895 96 (Reapproved 2010)Standard Test Methods forApparent Density, Bulk Factor, and Pourability of PlasticMaterials1This standard is issued under the fixed designation D1895; the number immediately following the designation indicates the year oforiginal adoption or, in the case of rev
2、ision, 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 These test methods
3、 cover the measurement of apparentdensity, bulk factor, and where applicable, the pourability ofplastic materials such as molding powders. Different proce-dures are given for application to the various forms of thesematerials that are commonly encountered, from fine powdersand granules to large flak
4、es and cut fibers.1.2 The values stated in SI units are to be regarded as thestandard. The values in parentheses are for information only.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
5、establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.NOTE 1Test MethodAis equivalent to ISO Method R 60 as describedin the appendix. Test Method C is identical with ISO Method R 61.2. Referenced Documents2.1 ASTM Standards:2D792 T
6、est Methods for Density and Specific Gravity (Rela-tive Density) of Plastics by DisplacementD883 Terminology Relating to PlasticsD1505 Test Method for Density of Plastics by the Density-Gradient Technique2.2 ISO Standards:3R60 Determination of Apparent Density of Molding Mate-rials that Can be Poure
7、d from a Specified FunnelR61 Determination of Apparent Density of Molding Mate-rial that Cannot be Poured from a Specified Funnel3. Terminology3.1 Definitions:3.1.1 apparent densitythe weight per unit volume of amaterial, including voids inherent in the material as tested.3.1.1.1 The term bulk densi
8、ty is commonly used for mate-rials such as molding powder.3.1.2 bulk factorthe ratio of the volume of any givenquantity of the loose plastic material to the volume of the samequantity of the material after molding or forming. The bulkfactor is also equal to the ratio of the density after molding orf
9、orming to the apparent density of the material as received.3.1.3 pourabilitya measure of the time required for astandard quantity of material to flow through a funnel ofspecified dimensions.4. Significance and Use4.1 These test methods provide useful indexes of perfor-mance of plastic materials such
10、 as powders and granules withrespect to their handling in packaging and fabrication.4.2 Apparent density is a measure of the fluffiness of amaterial.4.3 Bulk factor is a measure of volume change that may beexpected in fabrication.4.4 Pourability characterizes the handling properties of afinely divid
11、ed plastic material. It is a measure of the readinesswith which such materials will flow through hoppers and feedtubes and deliver uniform weights of material.APPARENT DENSITYTest Method A5. Scope5.1 Test Method A (see Note 1) covers the measurement ofthe apparent density of the fine granules and po
12、wders that canbe poured readily through a small funnel.1These test methods are under the jurisdiction of ASTM Committee D20 onPlastics and are the direct responsibility of Subcommittee D20.70 on AnalyticalMethods.Current edition approved Jan. 1, 2010. Published January 2010. Originallyapproved in 19
13、61. Last previous edition approved in 2003 as D1895 96(2003).This edition includes the addition of an extensive ISO equivalency statement andkeywords section. DOI: 10.1520/D1895-96R10.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm
14、.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1Copyright ASTM International, 100 Barr Harbor Dri
15、ve, PO Box C700, West Conshohocken, PA 19428-2959, United States.6. Apparatus6.1 Measuring CupA cylindrical cup of 100 6 0.5-cmcapacity, having a diameter equal to half the height, forexample, 39.9-mm (1.572-in.) inside diameter by 79.8-mm(3.144-in.) inside height, as shown in Fig. 1.6.2 Funnel, hav
16、ing a 9.5-mm diameter opening at thebottom, and mounted at a height 38 mm above the measuringcup, as shown in Fig. 1.7. Procedure7.1 With the apparatus assembled as shown in Fig. 1, closethe small end of the funnel with the hand or with a suitable flatstrip and pour a 115 6 5-cm3sample into the funn
17、el. Open thebottom of the funnel quickly and allow the material to flowfreely into the cup. If caking occurs in the funnel, the materialmay be loosened with a small glass rod.7.2 After all the material has passed through the funnel,immediately scrape off the excess on the top of the cup with astraig
18、htedge without shaking the cup. Weigh the material in thecup to the nearest 0.1 g. Calculate the weight in grams of 1 cm3of the material.NOTE 2To convert grams per cubic centimetre to ounces per cubicinch, multiply by 0.578. To convert to grams per cubic inch multiply by16.39. To convert grams per c
19、ubic centimetre to pounds per cubic foot,multiply by 62.43.NOTE 3Apparent density figures are not comparable except onmaterials having the same specific gravity after molding or forming.7.3 Very fine materials that will bridge and not flow throughthe funnel may be poured lightly from a paper held ap
20、proxi-mately 38 mm (1.5 in.) above the opening of the measuringcup.Test Method B8. Scope8.1 Test Method B covers the measurement of the apparentdensity of coarse, granular materials, including dice andpellets, that either cannot be poured or that pour with difficultythrough the funnel described in T
21、est Method A.9. Apparatus9.1 Measuring CupAcylindrical cup of 400-cm3capacity,as shown in Fig. 2.9.2 Funnel, having a 25.4-mm (1-in.) diameter opening atthe bottom, and mounted at a height 38 mm (1.5 in.) above themeasuring cup, as shown in Fig. 2.NOTE 4Finely divided powders may collect electrostat
22、ic chargeswhich, if present at the time of measurement, may result in variableapparent density values. Carbon black is a material that may be premixedwith the sample at concentrations of 0.05 to 0.2 weight percent to reducethis variability (Superba Black with a bulk density of about 8 lb/ft3hasbeen
23、found satisfactory for some materials).10. Procedure10.1 With the apparatus assembled as shown in Fig. 2, closethe small end of the funnel with the hand or with a suitable flatstrip and pour a 500 6 20-cm3sample into the funnel. Open thebottom of the funnel quickly and allow the material to flowfree
24、ly into the cup.NOTE 5The funnel described in Test Method B is also used for morefinely divided powders such as vinyl resins. While these powders usuallywill pour through this funnel, they may bridge in the 400-cm3cup shownin Fig. 2. To avoid this, the 100-cm3cup shown in Fig. 1 may besubstituted, a
25、nd the sample reduced to 115 6 5cm3.10.2 After all the material has passed through the funnel,immediately scrape off the excess on the top of the cup with aFIG. 1 Apparatus for Apparent Density Test, Method A FIG. 2 Apparatus for Apparent Density Test, Method BD1895 96 (2010)2straightedge without sh
26、aking the cup. Weigh the material in thecup to the nearest 0.1 g; then calculate the weight in grams of1cm3of the material. Make three determinations of theapparent density on each sample and average the results (Note2).Test Method C11. Scope11.1 Test Method C (see Note 1) covers the measurement oft
27、he apparent density of materials supplied in the form of coarseflakes, chips, cut fibers, or strands. Such materials cannot bepoured through the funnels described in Test MethodsAand B.Also, since they ordinarily are very bulky when loosely pouredand since they usually are compressible to a lesser b
28、ulk, evenby hand, a measure of their density under a small load isappropriate and useful.12. Apparatus12.1 Measuring CylinderA cylinder of 1000-cm3capac-ity, as shown in Fig. 3.12.2 Weight PlungerA cylinder closed at one end andhaving an outside diameter slightly smaller than the insidediameter of t
29、he measuring cylinder, as shown in Fig. 3. Theplunger shall have a scale cut on the outside surface, graduatedin intervals of 1 mm.13. Procedure13.1 Place the measuring cylinder on a piece of paper.Loosely drop 60 6 0.2 g of the material to be tested into themeasuring cylinder from a height approxim
30、ately that of thecylinder, taking care to lose none of the material and to drop itas uniformly as practicable. Before applying the weight, levelthe material in the measuring cylinder. Measure the height ofthe loose material in centimetres and identify this measurementas H1.13.2 Fill the weight plung
31、er with lead shot to obtain a totalweight of 2300 6 20 g (5.07 6 0.04 lb), including the plunger.Lower this weight gradually into the measuring cylinder untilit is entirely supported by the material. Allow the weight tosettle for 1 min and take the reading from the scale to thenearest 0.1 cm. This r
32、eading will give directly in centimetresthe height, H2, of the material.14. Precision and Bias14.1 Table 1 is based on a round-robin test conducted in198788, involving eight materials, tested by six laboratories.Each of the materials were commercial materials and weredistributed to the testing labor
33、atories on an “as received” bias.Each test result was based on three individual determinations,and was obtained either by Test Method A or B, dependentupon equipment availability in the individual laboratory. TestMethod C was not evaluated. Insufficient data were collectedfor the evaluation of bulk
34、factor and pourability because of theinherent properties of the tested materials, and limitations inthe equipment available to the laboratories involved in theinterlaboratory test.NOTE 6Specific materials are:Apoly(propylene)Bcellulose acetateCpoly(ethylene)Dnylon polyamideEpolyacetalFpoly(vinyliden
35、e chloride)Gpoly(vinyl chloride)Hpolyester (PETE)FIG. 3 Apparatus for Apparent Density Test, Method CD1895 96 (2010)314.2 In Table 1, for the materials indicated and for meanvalues that were derived from triplicate determinations:14.2.1 Sris the within-laboratory standard deviation of themean and Ir
36、= 2.83 Sr.14.2.2 SRis the between-laboratory standard deviation ofthe mean and IR= 2.83 SR.14.2.3 Vrand VRare the relative standard deviations for thewithin-laboratory and between-laboratory components in per-centage of the relevant mean.14.3 BiasSince no absolute test method exists for com-parison,
37、 no bias statement can be presented for this testmethod.15. Calculation15.1 Calculate the apparent density of the material beforeand after application of the load as follows, making separatecalculations for both H1, and H2:V 5 H 3 A (1)Apparent density 5 W/V (1)where:V = volume occupied by the mater
38、ial in the measuringcylinder, cm3,H = height of the material in the measuring cylinder, cm,A = cross-sectional area of the measuring cylinder, (61.89cm2), andW = weight of the material in the cylinder (60 g).15.2 Make three determinations of the apparent density oneach sample and average these resul
39、ts separately.16. Report16.1 Report each value of the apparent density and of theaverage density, both before and after loading.BULK FACTOR17. Procedure17.1 Apparent DensityMeasure the apparent density ofthe material in accordance with the applicable test method asdefined in Sections 5-15.17.2 Densi
40、ty After Molding or FormingMeasure the den-sity of the molded or formed plastic material in accordancewith either Test Method D1505, or Method A of Test MethodsD792, on two or more samples formed of the material underexamination. When the latter method is used, the averagespecific gravity, in genera
41、l, shall be assumed to be numericallyequal to the average density in grams per cubic centimetre. Ifthe shape of the formed specimen is such that its volume maybe readily and accurately calculated from its dimensions, thedensity may be determined by dividing the weight of thespecimen by its volume.18
42、. Calculation18.1 Calculate the bulk factor of the plastic material asfollows:Bulk factor 5 D2/D1(2)where:D2= average density of the molded or formed specimen,andD1= average apparent density of the plastic material priorto forming.19. Report19.1 Report the following information:19.1.1 Average appare
43、nt density of the plastic material andthe method employed,19.1.2 Average density of the molded or formed specimen,and19.1.3 Bulk factors (Note 7 and Note 8) calculated fromthem.NOTE 7Because bulk factor is a dimensionless ratio, it permitsranking of plastic materials, with respect to volume change u
44、pon fabrica-tion, regardless of their molded or formed density (or specific gravity).NOTE 8For measurements made in accordance with Test Method C,bulk factor before and after loading shall be reported. These shall beclearly identified.POURABILITY20. Apparatus20.1 The apparatus shall consist of the f
45、unnel described inTest Method A (6.2 and Fig. 1), mounted as shown, and eithera stopwatch or an electric timer of comparable accuracy.NOTE 9Pourability may be measured with the funnel described inTest Method B (9.2); however, the flow of material through this funnel isfrequently too rapid to yield m
46、eaningful results. Test Method C does notpermit measurement of pourability.21. Procedure21.1 Take a sample of the plastic material weighing, ingrams, 100 times its specific gravity (or density) after moldingor forming. Work this sample on a paper until there is notendency for the material to pack or
47、 cake. With the apparatusassembled as shown in Fig. 1, close the small end of the funnelwith the hand or with a suitable flat strip and pour the samplelightly into the funnel, avoiding any tendency to pack it. Thenquickly open the bottom of the funnel and start the stopwatchor timer at the same inst
48、ant.Allow the material to run from thefunnel as freely as it will, and stop the watch or timer at theinstant the last of it leaves the funnel.22. Report22.1 Report the time in seconds required for the funnel todischarge, to the nearest 0.2 s; or, if so found, that the materialwill not run through th
49、e funnel.TABLE 1 Precision and Bias DataAMaterial Average SrSRIrIRVrVRA 0.5372 0.0023 0.0256 0.0065 0.0724 0.43 4.77B 0.7342 0.0026 0.0377 0.0074 0.1067 0.35 5.14C 0.6191 0.0026 0.0230 0.0074 0.0651 0.42 3.71D 0.7314 0.0029 0.0342 0.0082 0.0968 0.39 4.67E 0.8766 0.0054 0.0302 0.0153 0.0855 0.62 3.44F 0.7819 0.0009 0.0165 0.0025 0.0467 0.11 2.11G 0.6092 0.0018 0.0112 0.0051 0.0317 0.30 1.83H 0.7975 0.0062 0.0350 0.0175 0.0991 0.77 4.39ASupporting data are available from ASTM Headquarters. Request D20-1161.D1895 96 (2010)423. Keywords23.1 apparent dens
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