ASTM B810-01a(2011)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: B810 − 01a (Reapproved 2011)
Standard Test Method for
Calibration of Atmospheric Corrosion Test Chambers by
Change in Mass of Copper Coupons
This standard is issued under the fixed designation B810; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope coupons are cleaned by a standard process. Each coupon is
weighed and the value is recorded.All coupons are exposed to
1.1 This test method covers the calibration of atmospheric
the corrosion test for a specified time. The coupons are
corrosion test chambers for electrical contacts that produce an
removed from the test and weighed and the new values are
adherent film of corrosion product on copper, such as a test
recorded. The change in weight for each coupon is calculated.
comprisedofamixtureofflowinggasesthatreactwithcopper.
Thecouponsaresubjectedtoadditionalanalysisasappropriate
1.2 This test method is not applicable to tests where
to determine the composition and thickness of any films
corrosion products may be removed from a copper surface
present on the surface.
during the test by fluids.
1.3 This test method is not applicable to tests where 4. Significance and Use
airborne solid or liquid material may be deposited on a copper
4.1 Electrical devices that contain electrical contacts gener-
surface during the test, as in a test which includes particulates
ally contain some copper-based materials.Atmospheric corro-
suspended in the atmosphere.
sion of copper parts in such devices often occurs in service
1.4 The values stated in SI units are to be regarded as
environments. A quantitative measure of the effect of a
standard. No other units of measurement are included in this
laboratory corrosion test on copper permits assessment of the
standard.
severity of the test. In addition, corrosion tests may be defined
in terms of their effect on copper; this test method provides a
1.5 This standard does not purport to address all of the
way of comparing one test against a standard defined
safety concerns, if any, associated with its use. It is the
elsewhere, or allows a comparison of the performance of a test
responsibility of the user of this standard to become familiar
over a period of time.Although this test method provides for a
with all hazards including those identified in the appropriate
relatively simple check of a test, the user is advised that
Material Safety Data Sheet (MSDS) for this product/material
additional analysis of the test chamber ambient is generally
as provided by the manufacturer, to establish appropriate
required to reproduce test conditions.
safety and health practices, and determine the applicability of
regulatory limitations prior to use.
4.2 Atmospheric corrosion tests are used on a variety of
materials besides copper. Care should be exercised in drawing
2. Referenced Documents
conclusions about the effects on such materials of apparently
2.1 ASTM Standards:
equivalent tests if the composition of gases or experimental
B845Guide for Mixed Flowing Gas (MFG) Tests for Elec-
conditionsaredifferent.Theprimaryuseofthiscalibrationtest
trical Contacts
method is to assure correlation among nominally identical
tests.
3. Summary of Test Method
3.1 Copper coupon samples of a well-defined size are
5. Apparatus
prepared and each is labeled for identification. All such
5.1 Racks or Fixtures suitable for holding the copper
coupons in the test chamber are required. Make these fixtures
This test method is under the jurisdiction of ASTM Committee B02 on
from a material that is not attacked by the corrosion test. The
Nonferrous Metals and Alloys and is the direct responsibility of Subcommittee
B02.11 on Electrical Contact Test Methods.
fixtures shall be designed to:
Current edition approved Oct. 1, 2011. Published October 2011. Originally
5.1.1 Hold the coupons in a vertical orientation,
approved in 1991. Last previous edition approved in 2006 as B810–01a(2006).
DOI: 10.1520/B0810-01AR11. 5.1.2 Hold the coupons so that they do not show any
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
perceptiblemotionwhenobservedwiththeunaidedeyeduring
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
the test,
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. 5.1.3 Cover less than 5% of the entire coupon surface area,
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B810 − 01a (2011)
5.1.4 Touch the coupon only with electrically insulating appropriate guidelines applied to cubic chambers. Thus, if the
parts and, x and z axes are 1.5 m and the y axis is 0.8 m, four grid lines
5.1.5 Allow free circulation of the ambient on both sides of would be used for the x and z axes and 3 grid lines would be
the coupon. used for the y axis when determining the grid for coupon
location.
5.2 In general, design all parts of the fixture to permit
7.1.3 For chambers with working volumes of other shapes
maximum circulation of the ambient around the coupon
than those covered in the preceding sections, devise a logical
surfaces. The size and positioning of the holding fixtures
placement pattern with a coupon density roughly equal to that
depends on the chamber size. Section 7 of this test method
specified for rectangular chambers.
gives requirements on the number and spacing of coupons; the
holding fixtures must be designed to comply with these
7.2 Select an appropriate duration of exposure for the
requirements.
copper coupons. Base this selection primarily upon the time
required for the test ambient to produce a statistically signifi-
5.3 Balance, with a capacity of at least 2 g and a resolution
cantweightchange.Additionalexposuretimemaybeaddedto
of 5 µg is required. Maintain the ambient in the vicinity of the
comply with other applicable requirements, specifications,
balance between 20 and 50% relative humidity.
agreements,etc.,orfortheconvenienceofthetestoperators,or
5.4 Fume Hood,toconductthechemicalcleaningprocedure
both. Generally, the test time shall be one or more whole days
of the coupons is required.
with a tolerance of 61h.
6. Reagents and Materials 7.3 Prepare the test coupons from wrought, annealed,
oxygen-free copper (99.95% copper minimum, copper alloy
6.1 Purity of Reagents—Reagent grade chemicals shall be
C10200) sheet. Select a thickness of sheet sufficiently stiff to
used in all tests. Unless otherwise indicated, it is intended that
resist bending during handling during the test but not so thick
all reagents conform to the specifications of the Committee on
3 that the edges become a significant portion of the surface area.
Analytical Reagents of the American Chemical Society
In general, thicknesses between 0.1 and 0.6 mm are recom-
where such specifications are available. Other grades may be
mended. Obtain material with a surface roughness less than
used, provided it is first ascertained that the reagent is of
0.15 µm center line average and use the material with the
sufficiently high purity to permit its use without lessening the
as-rolled surface finish. Make the coupons, squares or rect-
accuracy of the determination.
angles preferably 12.5 6 1.2 mm wide. One or two holes 2.5
mm or less in diameter may be added to aid in mounting.
7. Procedure
Inspect the edges of the coupons at 10× magnification for the
7.1 Use the requirements listed in 7.1.1 through 7.1.3 to
presence of burrs or slivers. If such features are found, they
determine the number of copper coupon specimens to be
mustberemovedsincetheymaycorrodeatamuchhigherrate
prepared.
than the coupon surface.
7.1.1 For chambers with cubic working volumes, use the
length of an edge to determine the number and placement of 7.4 Mark all coupons with a code giving each coupon a
unique identification. Make the characters in the code marking
coupons in accordance with the following rules. For chambers
with an edge dimension of 0.9 m or less, construct a reference about 2 mm high by engraving or stamping without ink.
grid with three equally spaced lines in each direction with the
7.5 During the cleaning procedure and at all times after
outer lines 0.1 m from the chamber wall and the third line
cleaning, handle coupons only with clean tweezers grasping in
centered between the outer lines. Place a coupon at each
theregionaroundtheidentificationmarking.Placeeachcopper
intersection of grid lines (27 coupons required). For chambers
couponinaseparateclean,dryglassvialofanappropriatesize
withanedgedimensionof0.9mto1.4m,constructareference
such that only the edges and corners of the coupons touch the
gridwithfourequallyspacedlinesineachdirection.Theouter
glass surfaces.
lines are placed 0.1 m from the chamber wall. Place a coupon
7.6 Clean all coupons in accordance with either of the two
at each intersection of grid lines (64 coupons required). For
procedures given in 7.6.1 through 7.6.2.5. Where a liquid bath
chambers with a maximum edge dimension greater than 1.4 m
is required, fill an appropriate vessel to a depth equal to or
butlessthan2.0m,constructareferencegridwithfiveequally
greater than 25 mm plus the largest dimension of the coupon
spacedlinesineachdirection.Theouterlinesareplaced0.1m
sample to be cleaned. Unless otherwise directed, change the
from the chamber wall. Place a coupon at each intersection of
fluid in all baths after 50 coupons have been processed. Unless
grid lines (125 coupons required).
otherwise directed, use all baths at room temperature.
7.1.2 For rectangular chambers with non-cubic working
(Warning—Conduct all operations involving acids and sol-
volumes, the guidelines for each dimension of the chamber
vents in a fume hood. Please be careful of N-Hexane. It is
al
...