ASTM B213-2003 Standard Test Method for Flow Rate of Metal Powders《金属粉末流速的标准试验方法》.pdf

1、Designation: B 213 03Standard Test Method forFlow Rate of Metal Powders1This standard is issued under the fixed designation B 213; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses i

2、ndicates the year of last reapproval. Asuperscript epsilon (e) 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 covers the determination of the flowrate of metal powders a

3、nd is suitable only for those powdersthat will flow unaided through the specified apparatus.1.2 The values stated in SI units are to be regarded as thestandard (except for the flowmeter funnel, which is fabricatedin inch-pound units). The values given in parentheses are forinformation only.1.3 This

4、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-bility of regulatory limitations prior to use.2. Referenced Documents2

5、.1 ASTM Standards:B 215 Practices for Sampling Finished Lots of Metal Pow-ders2B 243 Terminology of Powder Metallurgy23. Terminology3.1 Definitions Definitions of powder metallurgy termscan be found in Terminology B 243.3.2 Definitions of Terms Specific to This Standard:3.2.1 flow rate, nthe time re

6、quired for a powder sample ofstandard mass to flow through an orifice in a standard instru-ment according to a specified procedure.4. Summary of Test Method4.1 A weighed mass (50.0 g) of metal powder is timed as itflows through the calibrated orifice of a funnel.5. Significance and Use5.1 The rate a

7、nd uniformity of die cavity filling are relatedto flow properties, which thus influence production rates anduniformity of compacted parts.5.2 The ability of a powder to flow is a function ofinterparticle friction. As interparticle friction increases, flow isslowed. Fine powders may not flow.5.3 Humi

8、dity and moisture content influence flow rate. Wetor moist powders may not flow.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 quality control test byeither the producer or the end user.6. App

9、aratus6.1 Powder Flowmeter Funnel3A flowmeter funnel (Fig.1) having a calibrated orifice of 0.10 in. (2.54 mm) in diameter.NOTE 1The dimensions shown for the flowmeter funnel, includingthe orifice, are not to be considered controlling factors. Calibration withemery, as specified in Section 9, determ

10、ines the working flow rate of thefunnel.6.2 Stand3A stand (Fig. 2) to support the powder flow-meter funnel.6.3 BaseA level, vibration free base to support the pow-der flowmeter stand.6.4 Timing DeviceA stopwatch or other suitable devicecapable of measuring to the nearest 0.1 s.6.5 Chinese Emery3An e

11、mery powder used to calibratethe flowmeter funnel.6.6 BalanceA balance suitable for weighing at least 50.0g to the nearest 0.1 g.7. Sampling7.1 A quantity of powder sufficient to run the desirednumber of flow tests shall be obtained in accordance withPractices B 215.8. Preparation of Apparatus8.1 Cl

12、ean the funnel with clean dry toweling paper.8.2 Clean the funnel orifice with a clean dry pipe cleaner.9. Calibration of Apparatus9.1 The manufacturer supplies the powder flowmeter funnelcalibrated as follows:1This test method is under the jurisdiction of ASTM Committee B09 on MetalPowders and Meta

13、l Powder Products and is the direct responsibility of B09.02 onBase Metal Powders.Current edition approved Oct. 1, 2003. Published October 2003. Originallyapproved in 1946. Last previous edition approved in 1997 as B 213 97.2Annual Book of ASTM Standards, Vol 02.05.3The flowmeter funnel, stand, and

14、Chinese emery are available fromAcuPowderInternational, LLC.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.9.1.1 Heat an open glass jar of Chinese emery in a dryingoven at a temperature of 102 to 107C (215 to 225F) for 1h.9.1.2 Cool

15、 the emery to room temperature in a dessicator.9.1.3 Follow the procedure outlined in steps 10.1.1-10.1.8 .9.1.4 Repeat steps 10.1.2-10.1.8 using the identical 50.0 gmass of emery for all the tests until 5 flow times, the extremesof which shall not differ by more than 0.4 s, have beenrecorded.NOTE 2

16、The flow rate of Chinese emery calibration powder is sensi-tive to moisture. Starting from the dried condition, it will absorb moisturefrom the ambient air as five (or more) flow tests are performed. Flow timescan vary dependent upon the humidity of the test area.9.1.5 The average of these five flow

17、 times is stamped on thebottom of the funnel.9.2 The flow rate of Chinese emery powder was establishedby an interlaboratory study conducted by SubcommitteeB09.02 in 1995.4It represents the flow rate through the masterflowmeter funnel that had been used in a previous interlabo-ratory study with the f

18、ormer Turkish emery calibration powder,which is no longer available.9.3 It is recommended that the flow rate be checked peri-odically, at least every six months, using the procedure outlinedin steps 9.1.1-9.1.5. If the flow rate has changed from thatstamped on the instrument, the new correction fact

19、or will be40.0 divided by this new flow rate. Before adopting the newcorrection factor, however, it is recommended that the cause ofthe change be investigated. If the flow rate has increased (fasterflow), it is probable that repeated use has burnished the orificeand the new correction factor may be

20、used. A decrease in flowrate (slower flow) may indicate a plating of soft powder uponthe orifice. This should be removed carefully with the aid of apipe cleaner and the calibration test rerun, the new correctionfactor being calculated if required. It is recommended that theuse of a funnel be discont

21、inued after the flow rate of the emeryhas increased such that the time of flow is less than 37 s.10. Procedure10.1 Method 1Stationary Powder Start to Flow Measure-ment:10.1.1 Weigh out a 50.0 g mass of powder, as sampled, intoa clean weighing dish.10.1.2 Block the discharge orifice at the bottom of

22、thefunnel with a dry finger.10.1.3 Carefully pour the 50.0 g sample of powder into thecenter of the flowmeter funnel without any tapping, vibrationor movement of the funnel.10.1.4 Place the emptied weighing dish on the flowmeterstand directly under the funnel orifice.10.1.5 Simultaneously start the

23、stopwatch and remove yourfinger from the discharge orifice.10.1.6 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.4Supporting

24、 data is available from ASTM Headquarters.FIG. 1 Flowmeter FunnelFIG. 2 StandB21303210.1.7 Stop the stopwatch the instant the last of the powderexits the orifice.10.1.8 Record the elapsed time to the nearest 0.1 s.10.1.9 More than one flow may be run if desired. Use afresh 50.0 g quantity of powder

25、for each flow test. Average theflow times.10.2 Method 2Moving Powder Start to Flow Measure-ment:10.2.1 Place an empty receptacle directly under the dis-charge orifice.10.2.2 Weigh out a 50.0 g mass of powder, as sampled, intoa clean weighing dish.10.2.3 Pour the 50.0 g powder specimen into the cente

26、r ofthe funnel and start the stopwatch the instant the powder exitsthe orifice.10.2.4 Stop the stopwatch the instant the last of the powderexits the orifice.10.2.5 Record the elapsed time to the nearest 0.1 s.10.2.6 More than one flow may be run if desired. Use afresh 50.0 g quantity of powder for e

27、ach flow test. Average theflow times.11. Calculation11.1 Calculate the correction factor by dividing 40.0 byeither the flow rate stamped on the bottom of the funnel, or thenew calibration flow rate established in 9.3.11.2 Multiply the elapsed time (see 10.1.9 or 10.2.6)bythedesired correction factor

28、 (see 11.1).12. Report12.1 Report the corrected flow rate in seconds to the nearestsecond.13. Precision and Bias13.1 PrecisionPrecision has been determined from aninterlaboratory study performed by seven laboratories of Sub-committee B09.02.413.1.1 Repeatability intervals, r, are listed in Table 1.I

29、n95 % of flow rate determinations, on the basis of test erroralone, duplicate tests in the same laboratory by the sameoperator on one homogeneous lot of powder will differ by nomore than the stated amount in seconds.13.1.2 Reproducibility intervals, R , are listed in Table 1.For 95 % of comparative

30、trials done in two different laborato-ries, and on the basis of test error alone, single tests on thesame homogeneous lot of powder will differ by no more thanthe stated amount in seconds.13.2 BiasNo statement can be made about bias, becausethere is no standard reference material for flow rate measu

31、re-ment.14. Keywords14.1 flow rate; metal powder flow; powder flowASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any s

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34、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, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of thi

35、s 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).TABLE 1 Precision of Flow Rate Measurements of MetalPowdersPowderApparentDensity(g/cm3)FlowRate 3 Avg.(s/50 g)Repeatability(r ) Avg. 3Flows (s)Reproducibility(R ) Avg. 3Flows (s)Spherical bronze 5.04 12 0.1 0.8Iron #1 2.46 31 0.7 2.5Iron #2 3.03 26 1.0 2.1Iron (lubricated) 3.18 26 1.3 2.2Bronze premix(lubricated)3.31 31 1.7 2.6Brass(lubricated)3.61 42 4.1 8.7B213033