ASTM B328-96

Standard Test Method for Density, Oil Content, and Interconnected Porosity of Sintered Metal Structural Parts and Oil-Impregnated Bearings

SCOPE
1.1 This test method covers determination of the density, oil content, and interconnected porosity of sintered bearings and structural parts with or without oil impregnation.
1.2 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 09-Sep-1996
• Technical Committee: B09 - Metal Powders and Metal Powder Products
• Drafting Committee: B09.04 - Bearings

Relations

• Replaced By: ASTM B328-96(2003) - Standard Test Method for Density, Oil Content, and Interconnected Porosity of Sintered Metal Structural Parts and Oil-Impregnated Bearings
• Effective Date: 10-Apr-2003
• Referred By: ASTM B631-93(2021) - Standard Specification for Silver-Tungsten Electrical Contact Materials
• Effective Date: 10-Sep-1996
• Referred By: ASTM B663/B663M-20 - Standard Specification for Silver-Tungsten Carbide Electrical Contact Material
• Effective Date: 10-Sep-1996
• Referred By: ASTM B693-17(2022) - Standard Specification for Silver-Nickel Electrical Contact Materials
• Effective Date: 10-Sep-1996
• Referred By: ASTM B702-93(2019) - Standard Specification for Copper-Tungsten Electrical Contact Material
• Effective Date: 10-Sep-1996
• Referred By: ASTM B662/B662M-20 - Standard Specification for Silver-Molybdenum Electrical Contact Material
• Effective Date: 10-Sep-1996

Standards Content (Sample)

NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: B 328 – 96
Standard Test Method for
Density, Oil Content, and Interconnected Porosity of
Sintered Metal Structural Parts and Oil-Impregnated
Bearings
This standard is issued under the fixed designation B 328; 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 (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. Scope objects, the volume of water displaced by the immersed object
is determined by Archimedes principle. For porous P/M parts,
1.1 This test method covers determination of the density, oil
a method is required to seal surface connected pores. If the
content, and interconnected porosity of sintered bearings and
pores are not sealed or the part is not oil impregnated, the part
structural parts with or without oil impregnation.
will absorb some of the water and decrease its buoyancy and
1.2 The values stated in SI units are to be regarded as the
exhibit an erroneously high density.
standard. The values in parentheses are for information only.
4.2 Density and oil content values are generally contained in
1.3 This standard does not purport to address all of the
the specifications for oil-impregnated bearings and other self-
safety concerns, if any, associated with its use. It is the
lubricating P/M parts. Desired lubrication requires sufficient
responsibility of the user of this standard to establish appro-
interconnected porosity and satisfactory oil impregnation of the
priate safety and health practices and determine the applica-
porosity.
bility of regulatory limitations prior to use.
4.3 For a particular P/M material, the mechanical properties
2. Referenced Documents
of P/M structural parts are directly related to their density.
Density values are therefore generally contained in the speci-
2.1 ASTM Standards:
fications for P/M parts.
B 243 Terminology of Powder Metallurgy
D 1217 Test Method for Density and Relative Density
5. Apparatus
(Specific Gravity) of Liquids by Bingham Pycnometer
5.1 Analytical Balance, of sufficient capacity and accurate
D 1298 Practice for Density, Relative Density (Specific
to 0.01 % of the test specimen mass.
Gravity), or API Gravity of Crude Petroleum and Liquid
5.2 Device for weighing the test piece in air and in liquid
Petroleum Products by Hydrometer Method
(water); the water is distilled or deionized and preferably
3. Terminology
degassed. A wetting agent is added to the water, 0.05 to 0.1 %
by weight, to reduce surface tension effects.
3.1 Definitions of powder metallurgy (P/M) terms can be
5.3 Soxhlet Extractor, with oil solvent. Extractors may be
found in Terminology B 243. Additional descriptive informa-
purchased from most laboratory supply companies.
tion is available in the Related Material section of Vol 02.05 of
5.4 Apparatus for vacuum impregnation of the test piece
the Annual Book of ASTM Standards.
with oil.
4. Significance and Use
5.5 Beaker and Wires, of various sizes. A wire basket may
be used in place of wires (see Figs. 1 and 2).
4.1 The volume of an arbitrary P/M shape cannot be
5.6 Thermometer—Capable of reading temperature in the
accurately measured by standard techniques such as by mi-
range of 10 to 38°C (50 to 100°F) to an accuracy of 0.5°C
crometers or calipers. Since density is mass/volume, a precise
(1°F).
method to measure the volume is needed. For nonporous
This specification is under the jurisdiction of ASTM Committee B-9 on Metal
Powders and Metal Powder Products and is the direct responsibility of Subcom- Kodak Photo-Flo 200, available from Momentum Graphics, 400 D. Pierce St.,
mittee B09.04 on Bearings. Somerset, NJ 08873, or its equivalent, has been found suitable.
Current edition approved Sept. 10, 1996. Published November 1996. Originally Extractors may be purchased from Fisher Scientific, 585 Alpha Drive, Pitts-
published as B 328 – 58T. Last previous edition B 328 – 94. burgh, PA 15238; Cole-Parmer, 7425 North Oak Ave., Niles, IL 60714; V.W.R., P.O.
Annual Book of ASTM Standards, Vol 02.05. Box 15646, Philadelphia, PA 19105-5645; or Thomas Scientific, P.O. Box 99,
Annual Book of ASTM Standards, Vol 05.01. Swedesboro, NJ 08085-6099.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
B328–96
not more than 7 kPa (2 in. mercury) pressure for 30 min. Then
permit the pressure to increase to atmospheric pressure and the
specimen to remain immersed in oil 20 to 65 cSt (100 to 300
SSU) 38°C (100°F) at room temperature and pressure for 10
min.
7.3.2 Immerse the specimen in oil, viscosity of 20 to 65 cSt
(100 to 300 SSU) at 38°C (100°F), hold at a temperature of
82°C 6 5°C (180°F 6 10°F) for at least 4 h, and then cool to
room temperature by immersion in oil at room temperature.
7.4 To weigh the specimen in water, select a fine wire for
supporting the specimen. Suspend the wire from the beam
a. Twisted wire arrangement b. Basket support arrangement
hook, while the specimen is immersed in a beaker of distilled
FIG. 1 Methods for Holding Test Specimen When Weighing in
Water water. Support the beaker of water over the pan of the balance,
using a suitable bridge. The container of water may also be
supported below the balance for weighing specimens if the
5.7 Lubricant, of 20 to 65 cSt (100 to 300 SSU) at 38°C
balance has a lower beam hook for this purpose. See Fig. 2b.
(100°F).
Use a wetting agent (in the amount of 0.05 to 0.1 % by weight)
to reduce the effects of surface tension. The recommended
6. Test Specimen
diameter of wire (copper or stainless steel) to be used for
6.1 The specimen mass shall be a minimum of 1.0 g.
various weight range is as follows:
Several specimens may be used to reach the minimum mass.
less than 50 g − 0.12 mm (0.005 in.)
50 to less than 200 g − 0.25 mm (0.010 in.)
7. Procedure
200 to less than 600 g − 0.40 mm (0.015 in.)
7.1 Using an analytical balance, obtain the mass of the as
600 g and greater − 0.50 mm (0.020 in.)
received oil-containing specimen (Mass J), the oil-free speci-
In place of attaching the specimen on a wire, the use of a
men (Mass A), and the fully impregnated specimen (Mass B).
wire basket suspended in water may be used as an alternate
These, and all subsequent weighing, should be to 0.01 % of the
method (see Fig. 1b).
mass of the part, for example:
7.5 Twist the wire around the specimen and suspend it from
Specimen Mass, g Balance Sensitivity, g
the beam hook so that the specimen is completely immersed in
less than 10 0.0001 the water. The water should cover the specimen by at least 6
10 to less than 100 0.001
mm (0.25 in.) and the wire twist should be completely
100 to less than 1000 0.01
submerged. Immersion should be to the same point each time.
1000 to less than 10 000 0.1
Take care to ensure that no air bubbles adhere to the specimen
7.2 To determine Mass A, remove any oil from the samples
or to the wire. If a wire basket is used as an alternate method,
by extracting it in a Soxhlet apparatus of suitable size using
completely immerse the wire basket in the water.
toluol or petroleum ether as a solvent. After extracting for
7.6 Weigh the specimen and wire in water. This is Mass C.
approximately 1 h, remove the residual solvent by heating
If a wire basket is used as an alternate method, weigh the
samples1hat 120°C (250°F) and weigh upon cooling.
specimen and wire basket in water.
Continue alternate extractions and drying until the dry mass in
7.7 Remove the specimen and reweigh the wire in water
air is constant to 0.05 % of the mass of the part.
immersed to the same point
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