ASTM B808-10(2015)

Standard Test Method for Monitoring of Atmospheric Corrosion Chambers by Quartz Crystal Microbalances

SIGNIFICANCE AND USE
4.1 Corrosion film growth with thicknesses varying from a monolayer of atoms up to 1 μm can readily be measured on a continuous, real-time, in-situ, basis with QCMs.  
4.2 The test results obtained for this test method are influenced by various factors, including geometrical effects, temperature, humidity, film thickness, film materials, electrode conditions, gases in the corrosion chamber, atmospheric pressure, and so forth. Calibration of coated crystals and instrumentation and reproducible crystal operating conditions are necessary for consistent results.
SCOPE
1.1 This test method monitors the reactivity of a gaseous test environment in which metal surfaces (for example, electrical contacts, assembled printed wiring boards, and so forth) and other materials subject to pollutant gas attack undergo accelerated atmospheric corrosion testing. This test method is applicable to the growth of adherent corrosion films whose total corrosion film thickness ranges from a few atomic monolayers to approximately a micrometre.  
1.2 The test method provides a dynamic, continuous, in-situ, procedure for monitoring the corrosion rate in corrosion chambers; the uniformity of corrosion chambers; and the corrosion rate on different surfaces. Response time in the order of seconds is possible.  
1.3 With the proper samples, the quartz crystal microbalance (QCM) test method can also be used to monitor the weight loss from a surface as a result of the desorption of surface species (that is, reduction of an oxide in a reducing atmosphere). (Alternative names for QCM are quartz crystal oscillator, piezoelectric crystal oscillator, or thin-film evaporation monitor.)  
1.4 This test method is not sufficient to specify the corrosion process that may be occurring in a chamber, since a variety of pollutant gases and environments may cause similar weight gains.  
1.5 This test method is generally not applicable to test environments in which solid or liquid particles are deposited on the surface of the quartz crystal.  
1.6 The values stated in SI units are to be regarded as standard. The values in parentheses are for information only.  
1.7 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 Safety Data Sheet (SDS) 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-Sep-2015
• ICS: 77.060 - Corrosion of metals
• Technical Committee: B02 - Nonferrous Metals and Alloys
• Drafting Committee: B02.11 - Electrical Contact Test Methods

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: B808 − 10 (Reapproved 2015)
Standard Test Method for
Monitoring of Atmospheric Corrosion Chambers by Quartz
Crystal Microbalances
This standard is issued under the fixed designation B808; 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 Safety Data Sheet (SDS) for this product/material as provided
by the manufacturer, to establish appropriate safety and health
1.1 This test method monitors the reactivity of a gaseous
practices, and determine the applicability of regulatory limi-
test environment in which metal surfaces (for example, elec-
tations prior to use.
trical contacts, assembled printed wiring boards, and so forth)
and other materials subject to pollutant gas attack undergo
2. Referenced Documents
accelerated atmospheric corrosion testing. This test method is
applicable to the growth of adherent corrosion films whose
2.1 ASTM Standards:
total corrosion film thickness ranges from a few atomic
B810 Test Method for Calibration ofAtmospheric Corrosion
monolayers to approximately a micrometre.
Test Chambers by Change in Mass of Copper Coupons
1.2 The test method provides a dynamic, continuous, in-
3. Summary of Test Method
situ, procedure for monitoring the corrosion rate in corrosion
chambers; the uniformity of corrosion chambers; and the
3.1 A single crystal of quartz has various natural resonant
corrosion rate on different surfaces. Response time in the order
frequencies depending on the crystal’s size and shape. The
of seconds is possible.
decrease in natural frequency is linearly proportional to the
crystal mass and the mass of well-bonded surface films. For
1.3 With the proper samples, the quartz crystal microbal-
crystals with reactive metal films on the surface (usually
ance (QCM) test method can also be used to monitor the
driving electrodes), the mass of the crystal/metal film increases
weight loss from a surface as a result of the desorption of
as the metal oxidizes or forms other compounds with gases
surface species (that is, reduction of an oxide in a reducing
3,4
adsorbed from the atmosphere. Thus, by measuring the rate
atmosphere). (Alternative names for QCM are quartz crystal
of resonant frequency change, a rate of corrosion is measured.
oscillator, piezoelectric crystal oscillator, or thin-film evapora-
Non-adherent corrosion films, particles, and droplets yield
tion monitor.)
ambiguousresults.Areviewoftheoryandapplicationsisgiven
1.4 Thistestmethodisnotsufficienttospecifythecorrosion
in Lu and Czanderna. See Appendix X1 for discussion of the
process that may be occurring in a chamber, since a variety of
quantitative relationship between frequency change and mass
pollutant gases and environments may cause similar weight
change.
gains.
3.2 The chamber environmental uniformity and corrosion
1.5 This test method is generally not applicable to test
rate can be measured by placing matching quartz crystals with
environmentsinwhichsolidorliquidparticlesaredepositedon
matching reactive metal films at various locations in the
the surface of the quartz crystal.
chamber. If the chamber and corrosion rate have been
1.6 The values stated in SI units are to be regarded as
standardized, the corrosion rate on various surface materials
standard. The values in parentheses are for information only.
that have been deposited on the quartz crystal can be deter-
mined.
1.7 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
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
This test method is under the jurisdiction of ASTM Committee B02 on the ASTM website.
Nonferrous Metals and Alloys and is the direct responsibility of Subcommittee King, W. H. Jr., Analytical Chemistry, Vol 36, 1964, p. 173.
B02.11 on Electrical Contact Test Methods. Karmarkar,K.H.andGuilbaut,G.G., Analytical ChemistryActa,Vol75,1975,
Current edition approved Oct. 1, 2015. Published October 2015. Originally p. 111.
approved in 1997. Last previous edition approved in 2010 as B808 – 10. DOI: Lu, C. and Czanderna,A.W. Eds., Applications of Piezoelectric Quartz Crystal
10.1520/B0808-10R15. Microbalances, Elsevier, c1984.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B808 − 10 (2015)
4. Significance and Use nickel, zinc, gold, etc. electrodes. The preferred method of
deposition is by evaporation for a high purity, smooth surface.
4.1 Corrosion film growth with thicknesses varying from a
If sublayers are used to enhance the adhesion of the final
monolayer of atoms up to 1 µm can readily be measured on a
electrode, they should be covered by the final electrode
continuous, real-time, in-situ, basis with QCMs.
material so that less than 1 % of the metallic area is of exposed
4.2 The test results obtained for this test method are
sublayer material. Because of the fragility of the metal elec-
influenced by various factors, including geometrical effects,
trode there should be multiple (three or more), spring-loaded
temperature, humidity, film thickness, film materials, electrode
contacts between the crystal and electronics.
conditions, gases in the corrosion chamber, atmospheric
6.3 After metallization of the crystals, they should be stored
pressure, and so forth. Calibration of coated crystals and
in desiccators. After two years storage or if the metallization
instrumentation and reproducible crystal operating conditions
shows discoloration or staining, the crystals shall be discarded.
are necessary for consistent results.
Crystal surfaces should not be chemically or mechanically
5. Apparatus
cleaned before use in the corrosion chamber. They should be
blown clean with inert compressed gas. Chilling and conden-
5.1 Apparatus can be a simple series circuit of crystal (with
sation on the surface, as can occur with the use of pressurized
electrodes and sensing film), oscillator (typically 6 MHz) and
fluorocarbons, shall be avoided. Care shall be exercised so that
frequency counter (610-Hz accuracy and stability), as sche-
the crystals are only handled by clean tweezers or tongs and
matically shown in Fig. 1.
never touched by hands.
7. Calibration
7.1 QCMs and its electronics shall be calibrated initially in
a given corrosion system and thereafter on an annual basis.
Calibration shall be performed with the same shape and size of
crystal holder to be used during operation. Recalibration shall
FIG. 1 Schematic of QCM and Related Electronics
be performed if the crystal holder geometry is changed.
Calibration can be done by comparison to a standard such as
actual gravimetric weighing on a microbalance (62 µg). Use a
5.2 Commercial, Thin-Film Monitors, incorporating those
sample of the same material as the sensing film with a
functions that read out thicknesses or weight gain are also
minimum area of 5 cm and a thickness of 0.1 to 0.6 mm (see
available and acceptable after they have been calibrated.
Test Method B810). Foil surface roughness should be within
5.3 Microbalance, with an accuracy of 62 µg is needed for
620 % of the QCM sensing film roughness. The procedure for
calibration procedures.
the generation (that is, evaporation) and cleaning of the
5.4 Recording Devices or Computers are needed for real-
gravimetric sample should be the same as used for the sensing
time, continuous measurements.
films. The age and storage of the gravimetric sample should be
comparable to the age of the QCM sensing film.Allow the foil
6. Materials
to equilibrate with the microbalance atmosphere for 0.5 h, then
6.1 Crystals shall be of the AT cut variety with a resonant
weigh the sample with 62-µg accuracy before exposure.
frequency in the MHz range and matched to the frequency
Suspend the weighed gravimetric sample between two simi-
measuring apparatus used. Quartz crystal surfaces shall be
larly treated QCMs spaced 20 cm apart with the large surface
polished to a surface finish with an arithmetical mean
area dimension of the samples parallel to the air flow. After
deviation, R , of less than 0.1 µm. With this surface finish, th
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: B808 − 10 B808 − 10 (Reapproved 2015)
Standard Test Method for
Monitoring of Atmospheric Corrosion Chambers by Quartz
Crystal Microbalances
This standard is issued under the fixed designation B808; 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
1.1 This test method monitors the reactivity of a gaseous test environment in which metal surfaces (for example, electrical
contacts, assembled printed wiring boards, and so forth) and other materials subject to pollutant gas attack undergo accelerated
atmospheric corrosion testing. This test method is applicable to the growth of adherent corrosion films whose total corrosion film
thickness ranges from a few atomic monolayers to approximately a micrometre.
1.2 The test method provides a dynamic, continuous, in-situ, procedure for monitoring the corrosion rate in corrosion chambers;
the uniformity of corrosion chambers; and the corrosion rate on different surfaces. Response time in the order of seconds is
possible.
1.3 With the proper samples, the quartz crystal microbalance (QCM) test method can also be used to monitor the weight loss
from a surface as a result of the desorption of surface species (that is, reduction of an oxide in a reducing atmosphere). (Alternative
names for QCM are quartz crystal oscillator, piezoelectric crystal oscillator, or thin-film evaporation monitor.)
1.4 This test method is not sufficient to specify the corrosion process that may be occurring in a chamber, since a variety of
pollutant gases and environments may cause similar weight gains.
1.5 This test method is generally not applicable to test environments in which solid or liquid particles are deposited on the
surface of the quartz crystal.
1.6 The values stated in SI units are to be regarded as standard. The values in parentheses are for information only.
1.7 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)(SDS) 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.
2. Referenced Documents
2.1 ASTM Standards:
B810 Test Method for Calibration of Atmospheric Corrosion Test Chambers by Change in Mass of Copper Coupons
3. Summary of Test Method
3.1 A single crystal of quartz has various natural resonant frequencies depending on the crystal’s size and shape. The decrease
in natural frequency is linearly proportional to the crystal mass and the mass of well-bonded surface films. For crystals with
reactive metal films on the surface (usually driving electrodes), the mass of the crystal/metal film increases as the metal oxidizes
3,4
or forms other compounds with gases adsorbed from the atmosphere. Thus, by measuring the rate of resonant frequency change,
a rate of corrosion is measured. Non-adherent corrosion films, particles, and droplets yield ambiguous results. A review of theory
and applications is given in Lu and Czanderna. See Appendix X1 for discussion of the quantitative relationship between
frequency change and mass change.
This test method is under the jurisdiction of ASTM Committee B02 on Nonferrous Metals and Alloys and is the direct responsibility of Subcommittee B02.11 on
Electrical Contact Test Methods.
Current edition approved Oct. 1, 2010Oct. 1, 2015. Published October 2010October 2015. Originally approved in 1997. Last previous edition approved in 20052010 as
B808 – 05.B808 – 10. DOI: 10.1520/B0808-10.10.1520/B0808-10R15.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
King, W. H. Jr., Analytical Chemistry, Vol 36, 1964, p. 173.
Karmarkar, K. H. and Guilbaut, G. G., Analytical Chemistry Acta, Vol 75, 1975, p. 111.
Lu, C. and Czanderna, A. W. Eds., Applications of Piezoelectric Quartz Crystal Microbalances, Elsevier, c1984.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
B808 − 10 (2015)
3.2 The chamber environmental uniformity and corrosion rate can be measured by placing matching quartz crystals with
matching reactive metal films at various locations in the chamber. If the chamber and corrosion rate have been standardized, the
corrosion rate on various surface materials that have been deposited on the quartz crystal can be determined.
4. Significance and Use
4.1 Corrosion film growth with thicknesses varying from a monolayer of atoms up to 1 μm can readily be measured on a
continuous, real-time, in-situ, basis with QCMs.
4.2 The test results obtained for this test method are influenced by various factors, including geometrical effects, temperature,
humidity, film thickness, film materials, electrode conditions, gases in the corrosion chamber, atmospheric pressure, and so forth.
Calibration of coated crystals and instrumentation and reproducible crystal operating conditions are necessary for consistent
results.
5. Apparatus
5.1 Apparatus can be a simple series circuit of crystal (with electrodes and sensing film), oscillator (typically 6 MHz) and
frequency counter (610-Hz accuracy and stability), as schematically shown in Fig. 1.
FIG. 1 Schematic of QCM and Related Electronics
5.2 Commercial, Thin-Film Monitors, incorporating those functions that read out thicknesses or weight gain are also available
and acceptable after they have been calibrated.
5.3 Microbalance, with an accuracy of 62 μg is needed for calibration procedures.
5.4 Recording Devices or Computers are needed for real-time, continuous measurements.
6. Materials
6.1 Crystals shall be of the AT cut variety with a resonant frequency in the MHz range and matched to the frequency measuring
apparatus used. Quartz crystal surfaces shall be polished to a surface finish with an arithmetical mean deviation, R , of less than
a
0.1 μm. With this surface finish, the crystal appears optically transparent to the human eye.
6.2 Electrodes, used to drive the crystal’s resonant frequency, can be made from any electrically conducting material and usually
are a metal film evaporated on the quart crystal surface. The material under study or being used to calibrate the system may be
the same as or different than the electrode material. If the two materials are different, the potential corrosion of the electrodes shall
be accounted for during the design and subsequent experiments. Depending on the materials under test, the QCMs can have copper,
silver, nickel, zinc, gold, etc. electrodes. The preferred method of deposition is by evaporation for a high purity, smooth surface.
If sublayers are used to enhance the adhesion of the final electrode, they should be covered by the final electrode material so that
less than 1 % of the metallic area is of exposed sublayer material. Because of the fragility of the metal electrode there should be
multiple (three or more), spring-loaded contacts between the crystal and electronics.
6.3 After metallization of the crystals, they should be stored in desiccators. After two years storage or if the metallization shows
discoloration or staining, the crystals shall be discarded. Crystal surfaces should not be chemically or mechanically cleaned before
use in the corrosion chamber. They should be blown clean with inert compressed gas. Chilling and condensation on the surface,
as can occur with the use of pressurized fluorocarbons, shall be avoided. Care shall be exercised so that the crystals are only
handled by clean tweezers or tongs and never touched by hands.
7. Calibration
7.1 QCMs and its electronics shall be calibrated initially in a given corrosion system and thereafter on an annual basis.
Calibration shall be performed with the same shape and size of crystal holder to be used during operation. Recalibration shall be
performed if the crystal holder geometry is changed. Calibration can be done by comparison to a standard such as actual
gravimetric weighing on a microbalance (62 μg). Use a sample of the same material as the se
...