ASTM B970-09

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: B970 − 09
StandardTest Method for
Cleanliness of Powder Metallurgy (PM) Bearings and
Structural Parts
This standard is issued under the fixed designation B970; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 5. Significance and Use
1.1 This test method covers a quantitative procedure to
5.1 Residueonabearingmaybedetrimentaltoitslongevity
determine the cleanliness of PM bearings and structural parts. due to abrasive wear.
1.2 This is a laboratory test consisting of cleaning sample
5.2 Residue on structural parts may affect the fit of assem-
partsundercontrolledconditionsandcalculatingtheamountor
blies or disturb the performance of the entire piece of equip-
percent of residue from the mass of the removed contaminants.
ment via excess friction or wear.
1.3 The values stated in SI units are to be regarded as
5.3 Part producers can utilize this procedure to determine
standard. No other units of measurement are included in this
the cleanliness of their processes. High residue levels on
standard.
sintered parts may indicate a lubricant removal problem.
Residue levels may also indicate the condition of various fluids
1.4 This standard does not purport to address all of the
used in part processing.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
5.4 This test method can be applied when required by the
priate safety and health practices and determine the applica-
user or internally for process engineering or quality control/
bility of regulatory limitations prior to use.
compliance purposes by the producer.
2. Referenced Documents
6. Apparatus
2.1 ASTM Standards:
6.1 Basket—Perforated aluminum, wire or stainless steel
B243 Terminology of Powder Metallurgy
basket with handle to submerge parts in the solvent when using
cleaning Method A.
3. Terminology
6.2 Container—Glass or metal container sized to hold test
3.1 Definitions of PM terms can be found in Terminology
fluid and parts.
B243. Additional descriptive material is available in the
Related Materials section ofVolume 02.05 of theAnnual Book 6.3 Solvent—Laboratory grade toluene, petroleum ether or
of ASTM Standards. others as specified, since these are extremely flammable
materials, extra care should be used to avoid ignition sources.
4. Summary of Test Method
6.4 Filter apparatus and filters—Unless otherwise
4.1 The parts are washed with a solvent to remove surface
specified, a 10 µm nylon filter shall be used.
residue.
6.5 Analytical Balance—With a sensitivity of 0.0001 g.
4.2 The rinse solution is collected and filtered to capture the
6.6 Balance—Capable of weighing the parts tested to four
residue removed from the parts.
significant figures if reporting a mass %.
4.3 The filter is dried and the mass of residue measured.
6.7 Container— Weighing bottle or petri dishes.
6.8 Squirt Bottle—50 mL suggested.
This test method is under the jurisdiction of ASTM Committee B09 on Metal
6.9 Drying Oven—Capable of 120 °C, should be explosion
Powders and Metal Powder Products and are the direct responsibility of Subcom-
proof if solvent is highly flammable.
mittee B09.04 on Bearings.
Current edition approved Nov. 1, 2009. Published March 2010. DOI: 10.1520/
6.10 Vacuum Pump—Capableofsustainingapressurelower
B0970-09.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or than 70 kPa.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
6.11 Ultrasonic Bath—If used to replace manual agitation
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. (see section 8.2).
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B970 − 09
7. Interferences 8.2.5 Select the filter diameter to match the filter apparatus
being used for this test.
7.1 The larger the sample size the greater the precision that
8.2.6 Weigh the petri dish/bottle to the nearest 0.0001 g and
would be expected.
record its mass so it can be tared from the mass of container
7.2 2 The type of solvent can produce different results
plus filter. This container will be used to store the dried filter
depending on the aggressiveness of the solution.
from paragraph 8.2.7 and 8.3.4.
8.2.7 Dry the filter paper in the laboratory oven at approxi-
7.3 The cleanliness requirements of the application will
mately 120 °C for at least 15 min. Place the dried filter in a
dictate the aperture size of the filter.
covered petri dish or weighing bottle and cool to room
7.4 Thesizeofthepartsbeingtestedwillhaveadirecteffect
temperature.
on the number that need to be tested.
8.2.8 Determineandrecordthemassofthefilterpaper(petri
7.5 The samples shall be protected from external contami- dish or weighing bottle tared) to the nearest 0.0001 g; identify
this mass as P .
nation until ready to test.
8.2.9 Clean a glass or stainless steel container and place the
parts in the container.
8. Procedure
8.2.10 Fill the container with sufficient solvent to cover the
8.1 Cleaning and Rinsing the Parts – Method A:
parts.
8.1.1 The parties involved shall agree to the sample size and
8.2.11 Place the container with the solvent into the ultra-
sampling method. In no case shall the sample size be less than
sonic device. Operate the sonic cleaner for the agreed time and
100 g.
frequency.
8.1.2 Select the filter diameter to match the filter apparatus
8.2.12 Remove the parts from the solvent and rinse the parts
being used for this test.
with an additional 50-100 mL solvent using a squirt bottle,
8.1.3 Weigh the petri dish/bottle to the nearest 0.0001 g
...