1、Designation: B 855 06Standard Test Method forVolumetric Flow Rate of Metal Powders Using Arnold Meterand Hall Funnel1This standard is issued under the fixed designation B 855; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the yea
2、r 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 procedure for measuring theflow characteristics of a given volume of powder.1.2 The v
3、alues stated in SI units are to be regarded as thestandard (except for the Hall Flowmeter Funnel, which isproduced in inch-pound units). The values given in parenthesesare for information only.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. I
4、t 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:2B 213 Test Method for Flow Rate of Metal PowdersB 215 Practices for Sampling Me
5、tal PowdersB 243 Terminology of Powder MetallurgyB 703 Test Method for Apparent Density of Powders UsingArnold Meter3. Terminology3.1 DefinitionsUseful definitions of terms for metal pow-ders and powder metallurgy are found in Terminology B 243.3.2 Definitions of Terms Specific to This Standard:3.2.
6、1 volumetric flow ratethe time required for a givenvolume of powder to flow through an orifice in a standardinstrument according to a specified procedure.4. Summary of Test Method4.1 This test method consists of slowly sliding a bushingpartially filled with powder over a 20 cm3hole in a hardenedstee
7、l block. The volume of the powder obtained upon removalof the steel block is transferred to a Hall Flowmeter and theflow rate reported in seconds per 20 cm3.5. Significance and Use5.1 The volumetric flow rate is a measure of the flowcharacteristics of a metal powder. Measuring flow by volumeas compa
8、red with flow per unit mass eliminates the variable ofthe powder density.5.2 The ability of a powder to flow and pack is a function ofinterparticle friction. As the surface area increases, the amountof friction in a powder mass also increases. Consequently, thefriction between particles increases, g
9、iving less efficient flowand packing.5.3 Knowledge of the volumetric flow permits the numberof parts that can be made per hour to be estimated.5.4 This test method may be part of the purchase agreementbetween powder manufacturers and powder metallurgy (P/M)part producers, or it can be an internal qu
10、ality control test byeither the producer or the end user.6. Apparatus6.1 Arnold Density Meter3(Test Method B 703) a hard-ened, tempered, and demagnetized steel block having a centerhole 31.6640 6 0.0025 mm (1.2466 6 0.0001 in.) in diameterand a height of 25.4000 6 0.0025 mm (1.0000 6 0.0001 in.)that
11、 corresponds to a volume of 20 cm3(1.22 in.3)(Fig. 1).6.2 Bushingeither brass or bronze. Approximately 38 mm(1.50 in.) inside diameter (ID) by 45 mm (1.75 in.) outsidediameter (OD) by 38 mm (1.50 in.) long (Fig. 1).1This test method is under the jurisdiction of ASTM Committee B09 on MetalPowders and
12、 Metal Powder Products and is the direct responsibility of Subcom-mittee B09.02 on Base Metal Powders.Current edition approved July 1, 2006. Published July 2006. Originally approvedin 1994. Last previous edition approved in 1999 as B 855 94 (1999)e1.2For referenced ASTM standards, visit the ASTM web
13、site, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The sole source of supply of the Arnold Density Meter complete with bushingknown to the committee at this time
14、 is Arnold P/M Consulting Services, 648 CedarRoad, St. Marys, PA 15857. If you are aware of alternative suppliers, please providethis information to ASTM International Headquarters. Your comments will receivecareful consideration at a meeting of the responsible technical committee,1whichyou may atte
15、nd.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.3 Hall Flowmeter4(Test Method B 213) A standardflowmeter funnel having a calibrated orifice of 0.10 in. (2.54mm) i
16、n diameter complete with stand (Fig. 2).6.4 BaseA level, vibration-free base to support the HallFlowmeter.6.5 PaperGlazed or waxed paper measuring approxi-mately 150 mm by 150 mm square (6.0 in. by 6.0 in.).6.6 Timing DeviceStopwatch or other suitable device.7. Sampling7.1 Obtain a test sample in ac
17、cordance with Practices B 215.7.2 The powder sample shall be of sufficient volume to fillthe bushing to three-quarters of its height.8. Preparation of Apparatus8.1 Clean the steel block, bushing, and Hall funnel thor-oughly to eliminate any loose powder particles.9. Procedure9.1 Place the steel bloc
18、k on a sheet of glazed or waxedpaper.9.2 Place the bushing on the steel block on either side of thehole.9.3 Fill the bushing slowly and carefully to three-quarters ofits height with powder. (An inscribed ring on the ID of thebushing indicates the proper fill height.)9.4 With downward pressure on the
19、 bushing, slowly slidethe bushing towards the hole while twisting it. This gives asnowplow action to the powder as it falls slowly into the hole.Continue this motion until the bushing passes the hole. Stop,4The sole source of supply of the complete Hall Flowmeter known to thecommittee at this time i
20、sACuPowder International LLC, 901 LehighAvenue, UnionNJ 07083-7632. If you are aware of alternative suppliers, please provide thisinformation to ASTM International Headquarters. Your comments will receivecareful consideration at a meeting of the responsible technical committee,1whichyou may attend.F
21、IG. 1 Arnold Apparent Density MeterFIG. 2 Hall FlowmeterB855062and again with downward pressure on the bushing slide itstraight back over the hole to its starting position. The slidingaction must be slow enough to allow for complete filling of thesteel block cavity.9.5 Remove the steel block from th
22、e paper, being careful notto tip the block and spill additional powder on to the paper.9.6 The volumetric flow rate of the 20 cm3of powder maybe determined using either of the following methods:9.6.1 Method 1Stationary Powder Start to Flow Measure-ment:9.6.1.1 Block the discharge orifice at the bott
23、om of theflowmeter funnel with a dry finger.9.6.1.2 Carefully pour the 20 cm3of powder from the paperinto the center of the flowmeter funnel without any tapping,vibration, or movement of the funnel.9.6.1.3 Place an empty weighing dish under the dischargeorifice.9.6.1.4 Simultaneously start the stopw
24、atch and remove yourfinger from the discharge orifice.9.6.1.5 If the powder fails to start flowing, one light tap onthe funnel rim is permitted. Further tapping of the funnel,however, or poking or stirring of the powder in the funnel witha wire or any other implement is not permitted.9.6.1.6 Stop th
25、e stopwatch the instant the last of the powderexits the orifice.9.6.1.7 Record the elapsed time to the nearest 0.1 s.9.6.1.8 More than one flow may be run if desired. Use 20cm3of fresh powder for each flow test.Average the flow times.9.6.2 Method 2Moving Powder Start to Flow Measure-ment:9.6.2.1 Pla
26、ce an empty receptacle directly under the dis-charge orifice.9.6.2.2 Carefully pour the 20 cm3of powder into the centerof the funnel and start the stopwatch the instant the powderexits the orifice.9.6.2.3 Stop the stopwatch the instant the last of the powderexits the orifice.9.6.2.4 Record the elaps
27、ed time to the nearest 0.1 s.9.6.2.5 More than one flow may be run if desired. Use 20cm3of fresh powder for each flow test.Average the flow times.10. Report10.1 Multiply the flow time by the correction factor5andreport the results to the nearest second as the Arnold/Hall flowrate (s/20 cm3).11. Prec
28、ision and Bias11.1 PrecisionPrecision has been determined from aninterlaboratory study performed by Subcommittee B09.02.11.1.1 Volumetric Flow Rate Using the Arnold Meter andthe Hall Funnel:Repeatability r 5 1siron!,2slubricated bronze and brass! (1)11.1.1.1 In 95 % of such tests, on the basis of te
29、st erroralone, duplicate tests in the same laboratory by the sameoperator, on one homogeneous lot of powder will differ by nomore than the stated amount.Reproducibility R 5 2siron!,3slubricated bronze and brass!(2)11.1.1.2 For 95 % of comparative trials done in two differ-ent laboratories and on the
30、 basis of test error alone, single testson the same homogeneous lot of powder will differ by no morethan the stated amount.11.2 BiasNo bias statement can be made because there isno accepted standard or reference powder for volumetric flow.12. Keywords12.1 Arnold/Hall flow; interparticle friction; me
31、tal powders;volumetric flow rateSUMMARY OF CHANGESCommittee B09 has identified the location of selected changes to this standard since the last issue, B 855 94(1999)e1, that may impact the use of this standard. (Approved July 1, 2006.)(1) Revised the following sections: 5.1, 5.3, 8.1, and 9.4.(2) Re
32、vised Footnote 4.(3) Deleted previous sections 9.6 and 9.7 and listed twomethods that may be used for flow measurement in a revised9.6.(4) Indicated in 10.1 that the results are to be reported to thenearest second.5The correction factor is a value supplied by the manufacturer of the funnelusing a st
33、andardized powder. Periodically, the funnel must be calibrated with thestandard powder to compensate for orifice wear. For the calibration procedure referto Test Method B 213.B855063ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item
34、 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 responsible technical commi
35、ttee 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 careful consideration at a me
36、eting 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, 100 Barr Harbor Drive,
37、 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).B855064
