ASTM D6580-00(2005)
(Test Method)Standard Test Method for the Determination of Metallic Zinc Content in Both Zinc Dust Pigment and in Cured Films of Zinc-Rich Coatings
Standard Test Method for the Determination of Metallic Zinc Content in Both Zinc Dust Pigment and in Cured Films of Zinc-Rich Coatings
SIGNIFICANCE AND USE
This test method is useful for determining the amount of metallic zinc in zinc dust pigment, and also in dried films of both inorganic and organic zinc-rich coatings. Test Methods D 521 is an appropriate method for analyzing zinc dust, but has shortcomings when applied to samples of cured coatings.
SCOPE
1.1 This test method covers the determination of differential scanning calorimetry of the metallic zinc content of both zinc-dust pigment, and of dried films of zinc-rich coatings. This test method is applicable to both inorganic and organic zinc-rich coatings.
1.2 The values stated in SI units are to be regarded as the standard. The values given 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
Relations
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D6580–00(Reapproved2005)
Standard Test Method for
The Determination of Metallic Zinc Content in Both Zinc
Dust Pigment and in Cured Films of Zinc-Rich Coatings
This standard is issued under the fixed designation D 6580; 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.
1. Scope dynamic heating step, ranging from 370 to 435°C at 10°C per
min, under a nitrogen purge. The percent metallic zinc in the
1.1 Thistestmethodcoversthedeterminationbydifferential
sample is determined by measuring the energy associated with
scanning calorimetry of the metallic zinc content of both
the endothermic peak near 419°C caused by the melting of the
zinc-dust pigment, and of dried films of zinc-rich coatings.
metallic zinc, and comparing this value to the heat of fusion of
This test method is applicable to both inorganic and organic
pure zinc.
zinc-rich coatings
1.2 The values stated in SI units are to be regarded as the
4. Significance and Use
standard. The values given in parentheses are for information
4.1 This test method is useful for determining the amount of
only.
metallic zinc in zinc dust pigment, and also in dried films of
1.3 This standard does not purport to address all of the
both inorganic and organic zinc-rich coatings. Test Methods
safety concerns, if any, associated with its use. It is the
D 521isanappropriatemethodforanalyzingzincdust,buthas
responsibility of the user of this standard to establish appro-
shortcomings when applied to samples of cured coatings.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
5. Interferences
5.1 An increase or decrease in heating rate from those
2. Referenced Documents
specified may slightly alter the results. However, the variation
2.1 ASTM Standards:
would be expected to be minimal, so long as the zinc reference
D 521 Test Methods for Chemical Analysis of Zinc-Dust
standard and the samples are subjected to the same heating
(Metallic Zinc Powder)
rate.
E 691 Practice for Conducting an Interlaboratory Study to
5.2 Dailycalibrationofthecalorimeterwithhighpurityzinc
Determine the Precision of a Test Method
foil results in improved results. Reagent grade zinc granules or
3. Summary of Test Method zinc powder are of insufficient purity to properly calibrate the
instrument. Furthermore, the high purity-zinc foil should only
3.1 Samples of either zinc-dust pigment or of cured films of
beusedonetimeasacalibrationstandard.Warning:Usingthe
zinc-rich coatings are ground in a mortar and pestle, then
same piece of foil more than once can result in inaccurate
carefully weighed into standard differential scanning calorim-
results, due to oxidation of the zinc at the high temperatures in
etry (DSC) sample pans. The pans are then crimped shut, and
the calorimeter, coupled with the alloying effects of zinc with
analyzed in a differential scanning calorimeter in a single
the aluminum sample pans.
5.3 Important steps in achieving accurate and reproducible
This test method is under the jurisdiction of ASTM Committee D01 on Paint
results are very gentle tapping of the pan in order to distribute
and Related Coatings, Materials, and Applications , and is the direct responsibility
the sample evenly over the bottom of the pan, and careful
of Subcommittee D01.21 on Chemical Analysis of Paints and Paint Materials.
placement of the pan lid to avoid expulsion of the fine powder
Current edition approved July 1, 2005. Published August 2005. Originally
approved in 2000. Last previous edition approved in 2000 as D 6580 – 00. during crimping.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
NOTE 1—Round-robin testing has shown no evidence that pyrolysis of
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
the binder interferes with the measurement of the heat of fusion. Either
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. pyrolysis does not occur, occurs during stabilization of the instrument
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D6580–00 (2005)
prior to the scan, or is negligible due to the small amount of binder present
purge. The area under the endothermic transition correspond-
in such coatings. If there is reason to suspect interference from the binder,
ing to the melting (fusion) of zinc, in joules per gram, should
the analyst may wish to test a blank sample of binder (with no zinc
then be determined in the same fashion as described for the
pigment) to ensure that there is no effect on heat flow measurements.
zinc foil reference standard. Triplicate analyses should be
performed, and the results should be averaged to obtain the
6. Apparatus
average heat of fusion.
6.1 Differential Scanning Calorimeter, either of the heat
fluxorpowercompensationtype,capableofheatingratesupto
9. Calculation
at least 10 6 1°C/min and of automatic recording of difference
9.1 Calculate the percent metallic zinc in the sample as
in heat input between the sample and a reference mate
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.