1、Designation: E 194 06Standard Test Method forAcid-Insoluble Content of Copper and Iron Powders1This standard is issued under the fixed designation E 194; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、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 method2covers the determination of themineral-acid-insoluble matter content of copper and iron pow-ders in amounts under 1.
3、0 %.1.2 This standard does not purport to address all of thesafety problems, 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. Referenc
4、ed Documents2.1 ASTM Standards:3B 215 Practices for Sampling Metal PowdersE50 Practices for Apparatus, Reagents, and Safety Consid-erations for Chemical Analysis of Metals, Ores, andRelated MaterialsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. S
5、ummary of Test Method3.1 The sample is dissolved in the appropriate acid: nitricacid (HNO3) for copper, hydrochloric acid (HCl) for iron. Theinsoluble matter is filtered out and ignited in a furnace at980 C for 1 h.4. Significance and Use4.1 The purpose of this test method is to determine theamount
6、of gangue, refractory, inert, etc., materials, that mayadversely affect compacting tools and sintered properties ofcomponents formed from copper and iron powders.4.2 The insoluble matter consists of those nonmetallicsubstances that do not dissolve in the mineral acid used todissolve the metal. In co
7、pper powder, which is treated withnitric acid, the acid-insoluble matter includes silica, insolublesilicates, alumina, clays, and other refractory materials thatmay be introduced either as impurities in the raw material orfrom the furnace lining, fuel, etc.; lead sulfate may also bepresent. In iron
8、powder, which is treated with hydrochloricacid, the insoluble matter may include carbides in addition tothe substances listed above. The test method excludes insolublematerial that is volatile at the ignition temperature specified.5. Interferences5.1 Any metallic tin present in the copper powder wil
9、l beconverted into the insoluble tin oxide by the nitric acidtreatment; in such cases, provision shall be made for thedetermination of tin oxide and the appropriate correctionapplied.6. Apparatus6.1 Apparatus and reagents shall conform to the require-ments prescribed in Practices E50.6.2 Hot Plate.6
10、.3 Muffle Furnace, capable of operating at 980 C.6.4 Casseroles (non-metallic), 250 mL and 750 mL.6.5 Glass Funnel.6.6 Quart or Porcelain Crucible.6.7 Desiccator.6.8 Analytical Balance, having a sensitivity of 0.1 mg.6.9 Filter Paper, Whatman No. 541 or one of equivalentpore size and ash content.6.1
11、0 Vapor Collection System, suitable to provide adequateoperator protection from chemical vapors resulting from theacid digestion steps and muffle furnace ignition steps.7. Reagents7.1 Hydrochloric Acid HCl (1:1).7.2 Hydrochloric Acid HCl (1:25).7.3 Nitric Acid (HNO3).1This test method is under the j
12、urisdiction of ASTM Committee B09 on MetalPowders and Metal Powder Products and is the direct responsibility of Subcom-mittee B09.02 on Base Metal Powders.Current edition approved Oct. 1, 2006. Published October 2006. Originallyapproved in 1962. Last previous edition approved in 1999 as E 194 99.2Ba
13、sed on the method developed by the Metal Powder Association (now theMetal Powder Producers Association of the Metal Powder Industries Federation)and described in MPIF Standard 06, “Determination of Acid Insoluble Matter inIron and Copper Powders,” which is a standard of the MPIF.3For referenced ASTM
14、 standards, visit the ASTM website, 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.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM
15、 International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.7.4 Nitric Acid HNO3(1:1).7.5 Ammonium Iodide (NH4I).8. Sampling8.1 The metal powder shall be sampled in accordance withPractices B 215.8.2 Store the test sample in a tightly stoppered bottle toprotec
16、t it from moisture which promotes oxidation of copperand iron.COPPER POWDER9. Procedure9.1 Transfer5gofthesample, weighed to the nearest0.0001 g, to a 250 mL covered casserole.NOTE 1Some operators report better reproducibility when increasingthe metal powder sample size to 10 g. Nevertheless, the pr
17、ecisionstatement listed in Section 14 was based on 5 g samples.9.2 Add 100 mL of HNO3(1:1) and let stand at roomtemperature until the reaction is complete.9.3 Place the casserole on a hot plate and boil until thevolume is reduced to 50 mL.9.4 Cool, dilute with distilled water to about 100 mL, andbri
18、ng to a boil.9.5 Filter the hot solution, and wash with hot distilled wateruntil all traces of blue color (copper salts) disappear.9.6 Prepare a quartz or porcelain crucible by pre-heating for40 min in air at 980 C and then cool it in a desiccator.9.7 Weigh the crucible to the nearest 0.0001 g.9.8 T
19、ransfer the filter paper and residue to the crucible.9.9 Dry, and then ignite in a furnace at 980 C for 1 h.9.10 Cool in a desiccator and reweigh to the nearest0.0001 g. The difference in mass is the insoluble matter.Reserve the residue.NOTE 2If the ignited residue reserved from 9.2 is suspected to
20、containtin oxide, add5gofNH4I to the crucible. Reheat the crucible and contentsin air with a bunsen burner to a dull-red temperature or place in a furnaceat 600 C minimum for 15 min or until all fumes have been dispelled.Remove the crucible from the heat and cool. Add 2 to 3 mL of HNO3,evaporate to
21、dryness, ignite and weigh to the nearest 0.0001 g. Repeat thetreatment with NH4I and HNO3until constant mass is obtained. The lossin mass represents tin oxide. Subtract this loss in mass from the mass ofinsoluble matter determined in 9.10 to calculate the insoluble fraction thatis free of tin oxide.
22、10. Calculation10.1 Calculate the percentage of insoluble matter as fol-lows:Insoluble matter, percent 5 A 2 B!/C 3 100where:A = insoluble matter, g,B = correction for grams of tin oxide, if present (Note 2),andC = sample used, g.IRON POWDER11. Procedure11.1 Transfer5gofthesample, weighed to the nea
23、rest0.0001 g, to a 750 mL covered casserole.NOTE 3Some operators report better reproducibility when increasingthe metal powder sample size to 10 g. Nevertheless, the precisionstatement listed in Section 14 was based on 5 g samples.11.2 With caution, add 100 mL of HCl (1:1) (Note 4), andlet stand at
24、room temperature until the reaction is complete.11.3 Heat the solution to boiling on a hot plate, add 150 mLof water, and reheat to boiling.11.4 Add 150 mL of distilled water and reheat to boiling.11.5 Filter the hot solution, and wash the residue alternatelywith hot HCl (1:25) and hot distilled wat
25、er, six times with each,to ensure the removal of all iron salts.NOTE 4If it is desired to exclude carbides from the reported insolublematter, add 20 mL of HNO3to the HCl (1:1).11.6 Prepare a quartz or porcelain crucible by pre-heatingfor 40 min in air at 980 C and then cool it in a dessicator.11.7 W
26、eigh the crucible to the nearest 0.0001 g.11.8 Transfer the filter paper and residue to the crucible.11.9 Dry, and then ignite in a furnace at 980 C for 1 h.11.10 Cool in a desiccator and reweigh to the nearest0.0001 g. The difference in mass is the insoluble matter.12. Calculation12.1 Calculate the
27、 percentage of insoluble matter as fol-lows:Insoluble matter, percent 5 A/B 3 100where:A = insoluble matter, g, andB = sample used, g.13. Report13.1 Report the total insoluble matter as a percentage to thenearest 0.01 %.14. Precision and Bias14.1 PrecisionThe following precision data were devel-oped
28、 using the procedures contained in Test Method E 194from an interlaboratory study that performed six sets of tests.The percent insoluble was determined for four samples: a 325mesh iron, a 60 mesh iron, a 325 mesh copper, and a 60mesh copper. The different particle sizes were used to deter-mine if th
29、ere were any effects on the precision of testing basedon differences in particle size distribution. Practice E 691 wasfollowed for the design and analysis of the data; the details aregiven in an ASTM Research Report.414.1.1 The precision information given below is for thecomparison of two test resul
30、ts. The results were obtained fromthe running of three replicates in each test on each sample.325Iron60Iron325Copper60CopperAverage, % 0.29 0.08 0.11 0.09Sr, % 0.022 0.012 0.013 0.019SR, % 0.051 0.025 0.036 0.063r, % 0.06 0.03 0.04 0.05R, % 0.14 0.07 0.10 0.184Supporting data have been filed at ASTM
31、 International Headquarters and maybe obtained by requesting Research Report RR: B091009.E19406214.1.2 Duplicate results from the same laboratory should beconsidered acceptable at the 95 % confidence level unless theydiffer by more than r, the repeatability interval.14.1.3 Duplicate results from two
32、 different laboratoriesshould be considered acceptable at the 95 % confidence levelunless they differ by more than R, the reproducibility interval.14.2 BiasNo information can be presented on the bias ofthe procedure in Test Method E 194 for measuring the acidinsoluble content of copper and iron powd
33、ers because nomaterial having an accepted reference value is available.15. Keywords15.1 acid insolubles; copper powder; iron powderSUMMARY OF CHANGESCommittee B09 has identified the location of selected changes to this standard since the last issue (E 194 99)that may impact the use of this standard.
34、 (Approved Oct. 1, 2006.)(1) Provided additional detail for the apparatus and reagentsrequired in Section 6.(2) In Section 9, the procedure for copper powders has beenbroken down into a larger number of sections and someadjustments have been made to the description of the proce-dure.(3) New Note 1 h
35、as been added to indicate that some operatorsfind better precision when using a sample mass of 10 g ratherthan 5 g.(4) In Section 11, the procedure for iron powders has beenbroken down into a larger number of sections and someadjustments have been made to the description of the proce-dure.(5) New No
36、te 3 has been added to indicate that some operatorsfind better precision when using a sample mass of 10 g ratherthan 5 g.ASTM 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 expres
37、sly 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 committee and must be reviewed every five years andif not revised,
38、 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 meeting of theresponsible technical committee, which you may at
39、tend. 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, 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).E194063
