1、Designation: B212 09Standard Test Method forApparent Density of Free-Flowing Metal Powders Using theHall Flowmeter Funnel1This standard is issued under the fixed designation B212; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、 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 This test method describes a
3、 procedure for determiningthe apparent density of free-flowing metal powders, and mixedpowders; and is suitable for only those powders that will flowunaided through the specified Hall Flowmeter funnel.1.2 With the exception of density values, for which theg/cm3unit is the industry standard, the valu
4、es stated in SI unitsare to be regarded as the standard. Values in inch-pound unitsare shown in parentheses and result from conversion inaccordance with IEEE/ASTM Standard SI 10. They may beapproximate and are only for information.1.3 This standard does not purport to address all of thesafety concer
5、ns, 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:2B215 Practices for Sampling Metal Powders
6、B243 Terminology of Powder MetallurgyB873 Test Method for Measuring Volume of ApparentDensity Cup Used in Test Methods B 212, B 329, and B4172.2 IEEE/ASTM Standard:2SI 10 American National Standard for Use of the Interna-tional System of Units (SI): The Modern Metric System3. Terminology3.1 Definiti
7、onsFor definitions of terms used in this testmethod, see Terminology B243. Additional descriptive PMinformation is available in the Related Materials section of Vol02.05 of the Annual Book of ASTM Standards.4. Summary of Test Method4.1 Avolume of powder is permitted to flow into a containerof defini
8、te volume under controlled conditions. The mass ofpowder per unit volume is determined and reported as apparentdensity, Hall (ADH).5. Significance and Use5.1 This test method provides a guide for evaluation of animportant physical characteristic of a powder known as theapparent density. The measured
9、 apparent density bears arelationship to the mass of powder that will fill a fixed volumedie cavity. The degree of correlation between the results of thistest and the performance of powders during use may vary witheach particular application. Note, however, that the presence ofmoisture, oils, steari
10、c acid, stearates, waxes, and the tempera-ture of the powder mass may alter the physical characteristicsof the powder.6. Apparatus6.1 Powder Flowmeter Funnel3A Hall Flowmeter funnel(Fig. 1) having a calibrated orifice.6.2 Density Cup3A cylindrical brass cup (Fig. 2) having anominal capacity of 25 cm
11、3. The actual cup volume shall bedetermined according to Test Method B873.6.3 Stand3A stand (Fig. 1) to support the Hall Flowmeterfunnel concentric with the density cup so that the bottom of theHall Flowmeter funnel orifice is approximately 25 mm (1 in.)above the top of the density cup when the appa
12、ratus isassembled as shown in Fig. 1.6.4 BaseA level, vibration-free base to support the pow-der flowmeter.1This test method is under the jurisdiction of ASTM Committee B09 on MetalPowders and Metal Powder Products and is the direct responsibility of Subcom-mittee B09.02 on Base Metal Powders.Curren
13、t edition approved Nov. 1, 2009. Published January 2010. Originallyapproved in 1946. Last previous edition approved in 2006 as B212 99(2006) .DOI: 10.1520/B0212-09.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Boo
14、k of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The sole source of supply of the apparatus known to the committee at this timeisAccu Powder International, LLC, 901 LehighAve., Union, NJ 07083-7632. If youare aware of alternative suppliers, plea
15、se provide this information to ASTMInternational Headquarters. Your comments will receive careful consideration at ameeting of the responsible technical committee,1which you may attend.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
16、6.5 Balance A laboratory balance, having a capacity of atleast 200 g and a sensitivity of 0.001 g.6.6 Spatula A non-magnetic spatula of suitable dimen-sions for leveling off the excess powder on top of the densitycup.7. Test Specimen7.1 The test specimen shall consist of a volume of approxi-mately 3
17、0 to 40 cm3of metal powder obtained in accordancewith Practices B215.7.2 The test specimen shall be tested as sampled.8. Procedure8.1 Weigh the empty density cup to the nearest 0.01 g or,alternatively, place the empty density cup on the balance andtare the balance to zero.8.2 Carefully load the test
18、 specimen into the flowmeterfunnel and permit it to run into the density cup through thedischarge orifice. Take care not to move the density cup.FIG. 1 Flowmeter Apparatus Hall FunnelFIG. 2 Density Cup (25 6 0.03 cm2)B212 0928.3 After the powder has completely filled the cup and hasbegun to overflow
19、 the periphery of the density cup, rotate thefunnel approximately 90 in a horizontal plane so that theremaining powder falls away from the cup.8.4 Using a nonmagnetic spatula with the blade held per-pendicular to the top edge of the cup, level off the powder flushwith the top of the density cup. Tak
20、e care to avoid jarring theapparatus at any time.8.5 After the leveling operation, tap the density cup lightlyon the side to settle the powder to avoid spilling duringtransfer. Wipe off any powder sticking to the outside wall of thecup.8.6 Transfer the filled density cup to the balance and weighto t
21、he nearest 0.01 g to determine the mass, M, of powder.9. Calculation9.1 Calculate the apparent density as follows:ADH5MV(1)where:M = mass of powder in the density cup, g.V = volume of the density cup, cm3.ADH= apparent density, Hall.10. Report10.1 Report the results as apparent density, Hall (ADH)to
22、the nearest 0.01 g/cm3.11. Precision and Bias11.1 PrecisionThe precision of this test method as deter-mined by the statistical examination of the interlaboratory testresults is as follows:11.1.1 Repeatability r = 1.5 %Duplicate analyses of un-lubricated or lubricated metal powders by the same operat
23、orand same apparatus should not differ by more than 1.5 % at the95 % confidence level.11.1.2 Reproducibility R = 3 % (unlubricated and lubri-cated iron powder), R = 5 % (lubricated brass and bronzepowders). The difference between two single and independentresults obtained by different operators work
24、ing in differentlaboratories on lubricated and unlubricated iron powdersshould not differ by more than 3 % at the 95 % confidencelevel. Analyses of lubricated brass and bronze metal powdersshould not differ by more than 5 % at the 95 % confidencelevel.11.2 BiasSince there is no accepted reference ma
25、terial fordetermining the bias for the procedure in Test Method B212 formeasuring apparent density, Hall, bias has not been deter-mined.12. Keywords12.1 apparent density; Hall flowmeter funnel; metalpowdersASTM International takes no position respecting the validity of any patent rights asserted in
26、connection 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 res
27、ponsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive caref
28、ul consideration 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
29、, 100 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 website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).B212 093
