Standard Test Method for Calibration of Atmospheric Corrosion Test Chambers by Change in Mass of Copper Coupons

SIGNIFICANCE AND USE
Electrical devices that contain electrical contacts generally contain some copper-based materials. Atmospheric corrosion of copper parts in such devices often occurs in service environments. A quantitative measure of the effect of a laboratory corrosion test on copper permits assessment of the severity of the test. In addition, corrosion tests may be defined in terms of their effect on copper; this test method provides a way of comparing one test against a standard defined elsewhere, or allows a comparison of the performance of a test over a period of time. Although this test method provides for a relatively simple check of a test, the user is advised that additional analysis of the test chamber ambient is generally required to reproduce test conditions.
Atmospheric corrosion tests are used on a variety of materials besides copper. Care should be exercised in drawing conclusions about the effects on such materials of apparently equivalent tests if the composition of gases or experimental conditions are different. The primary use of this calibration test method is to assure correlation among nominally identical tests.
SCOPE
1.1 This test method covers the calibration of atmospheric corrosion test chambers for electrical contacts that produce an adherent film of corrosion product on copper, such as a test comprised of a mixture of flowing gases that react with copper.
1.2 This test method is not applicable to tests where corrosion products may be removed from a copper surface during the test by fluids.
1.3 This test method is not applicable to tests where airborne solid or liquid material may be deposited on a copper surface during the test, as in a test which includes particulates suspended in the atmosphere.
1.4 The values stated in SI units are to be regarded as the standard.
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 become familiar with all hazards including those identified in the appropriate Material Safety Data Sheet (MSDS) for this product/material as provided by the manufacturer, to establish appropriate safety and health practices, and determine the applicability of regulatory limitations prior to use.

General Information

Status
Historical
Publication Date
30-Nov-2006
Current Stage
Ref Project

Relations

Buy Standard

Standard
ASTM B810-01a(2006) - Standard Test Method for Calibration of Atmospheric Corrosion Test Chambers by Change in Mass of Copper Coupons
English language
6 pages
sale 15% off
Preview
sale 15% off
Preview

Standards Content (Sample)


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(Reapproved2006)
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. 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 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.
comprised of a mixture of flowing gases that react with copper.
The coupons are subjected to additional analysis as appropriate
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 the
environments. A quantitative measure of the effect of a
standard.
laboratory corrosion test on copper permits assessment of the
1.5 This standard does not purport to address all of the
severity of the test. In addition, corrosion tests may be defined
safety concerns, if any, associated with its use. It is the
in terms of their effect on copper; this test method provides a
responsibility of the user of this standard to become familiar
way of comparing one test against a standard defined else-
with all hazards including those identified in the appropriate
where, or allows a comparison of the performance of a test
Material Safety Data Sheet (MSDS) for this product/material
over a period of time.Although this test method provides for a
as provided by the manufacturer, to establish appropriate
relatively simple check of a test, the user is advised that
safety and health practices, and determine the applicability of
additional analysis of the test chamber ambient is generally
regulatory limitations prior to use.
required to reproduce test conditions.
2. Referenced Documents 4.2 Atmospheric corrosion tests are used on a variety of
materials besides copper. Care should be exercised in drawing
2.1 ASTM Standards:
conclusions about the effects on such materials of apparently
B845 Guide for Mixed Flowing Gas (MFG) Tests for
equivalent tests if the composition of gases or experimental
Electrical Contacts
conditions are different.The primary use of this calibration test
3. Summary of Test Method
method is to assure correlation among nominally identical
tests.
3.1 Copper coupon samples of a well-defined size are
prepared and each is labeled for identification. All such
5. Apparatus
5.1 Racks or Fixtures suitable for holding the copper cou-
This test method is under the jurisdiction of ASTM Committee B02 on
pons in the test chamber are required. Make these fixtures from
Nonferrous Metals and Alloys and is the direct responsibility of Subcommittee
amaterialthatisnotattackedbythecorrosiontest.Thefixtures
B02.11 on Electrical Contact Test Methods.
shall be designed to:
Current edition approved Dec. 1, 2006. Published December 2006. Originally
approved in 1991. Last previous edition approved in 2001 as B810 – 01a. DOI:
5.1.1 Hold the coupons in a vertical orientation,
10.1520/B0810-01AR06.
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
perceptible motion when observed with the unaided eye during
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.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
B810–01a (2006)
5.1.3 Cover less than 5 % of the entire coupon surface area, appropriate guidelines applied to cubic chambers. Thus, if the
5.1.4 Touch the coupon only with electrically insulating x and z axes are 1.5 m and the y axis is 0.8 m, four grid lines
parts and, would be used for the x and z axes and 3 grid lines would be
5.1.5 Allow free circulation of the ambient on both sides of used for the y axis when determining the grid for coupon
the 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 6 of this test method
specified for rectangular chambers.
gives requirements on the number and spacing of coupons; the
7.2 Select an appropriate duration of exposure for the
holding fixtures must be designed to comply with these
copper coupons. Base this selection primarily upon the time
requirements.
required for the test ambient to produce a statistically signifi-
5.3 Balance, with a capacity of at least 2 g and a resolution
cant weight change.Additional exposure time may be added to
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.
7.3 Prepare the test coupons from wrought, annealed,
6. Reagents and Materials
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
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 103 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
must be removed since they may corrode at a much higher rate
prepared.
than the coupon surface.
7.1.1 For chambers with cubic working volumes, use the
7.4 Mark all coupons with a code giving each coupon a
length of an edge to determine the number and placement of
unique identification. Make the characters in the code marking
coupons in accordance with the following rules. For chambers
about 2 mm high by engraving or stamping without ink.
with an edge dimension of 0.9 m or less, construct a reference
7.5 During the cleaning procedure and at all times after
grid with three equally spaced lines in each direction with the
cleaning, handle coupons only with clean tweezers grasping in
outer lines 0.1 m from the chamber wall and the third line
theregionaroundtheidentificationmarking.Placeeachcopper
centered between the outer lines. Place a coupon at each
coupon in a separate clean, dry glass vial of an appropriate size
intersection of grid lines (27 coupons required). For chambers
such that only the edges and corners of the coupons touch the
withanedgedimensionof0.9mto1.4m,constructareference
glass surfaces.
grid with four equally spaced lines in each direction. The outer
7.6 Clean all coupons in accordance with either of the two
lines are placed 0.1 m from the chamber wall. Place a coupon
procedures given in 7.6.1 through 7.6.2.5. Where a liquid bath
at each intersection of grid lines (64 coupons required). For
is required, fill an appropriate vessel to a depth equal to or
chambers with a maximum edge dimension greater than 1.4 m
greater than 25 mm plus the largest dimension of the coupon
but less than 2.0 m, construct a reference grid with five equally
sample to be cleaned. Unless otherwise directed, change the
spaced lines in each direction. The outer lines are placed 0.1 m
fluid in all baths after 50 coupons have been processed. Unless
from the chamber wall. Place a coupon at each intersection of
otherwise directed, use all baths at room temperature.
grid lines (125 coupons required).
(Warning—Conduct all operations involving acids and sol-
7.1.2 For rectangular chambers with non-cubic working
vents in a fume hood. Please be careful of N-Hexane. It is
volumes, the guidelines for each dimension of the chamber
extremely flammable.)(Warning—D
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.