ASTM D934-22

Standard Practices for Identification of Crystalline Compounds in Water-Formed Deposits By X-Ray Diffraction

SIGNIFICANCE AND USE
5.1 The identification of the crystalline structures in water-formed deposits assists in the determination of the deposit sources and mode of deposition. This information may lead to measures for the elimination or reduction of the water-formed deposits.
SCOPE
1.1 These practices provide for X-ray diffraction analysis of powdered crystalline compounds in water-formed deposits. Two are given as follows:    
Sections  
Practice A—Camera  
12 to 21  
Practice B—Diffractometer  
22 to 30  
1.2 Both practices yield qualitative identification of crystalline components of water-formed deposits for which X-ray diffraction data are available or can be obtained. Greater difficulty is encountered in identification when the number of crystalline components increases.  
1.3 Amorphous phases cannot be identified without special treatment. Oils, greases, and most organic decomposition products are not identifiable.  
1.4 The sensitivity for a given component varies with a combination of such factors as density, degree of crystallization, particle size, coincidence of strong lines of components and the kind and arrangement of the atoms of the components. Minimum percentages for identification may therefore range from 1 % to 40 %.  
1.5 The values stated in SI units are to be regarded as standard. The values listed in parenthesis are for information only.  
1.6 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 8 and Note 20.  
1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 30-Jun-2022
• ICS: 13.060.30 - Sewage water
• Technical Committee: D19 - Water
• Drafting Committee: D19.03 - Sampling Water and Water-Formed Deposits, Analysis of Water for Power Generation and Process Use, On-Line Water Analysis, and Surveillance of Water

Relations

• Refers: ASTM D1129-13(2020)e2 - Standard Terminology Relating to Water
• Effective Date: 01-May-2020
• Refers: ASTM D933-20 - Standard Practice for Reporting Results of Examination and Analysis of Water-Formed Deposits
• Effective Date: 01-May-2020
• Refers: ASTM E11-13 - Standard Specification for Woven Wire Test Sieve Cloth and Test Sieves
• Effective Date: 01-Oct-2013
• Refers: ASTM D933-84(2012) - Standard Practice for Reporting Results of Examination and Analysis of Water-Formed Deposits
• Effective Date: 01-Jan-2012
• Refers: ASTM D1129-10 - Standard Terminology Relating to Water
• Effective Date: 01-Mar-2010
• Refers: ASTM E11-09e1 - Standard Specification for Woven Wire Test Sieve Cloth and Test Sieves
• Effective Date: 01-May-2009
• Refers: ASTM D2331-08 - Standard Practices for Preparation and Preliminary Testing of Water-Formed Deposits
• Effective Date: 01-Oct-2008
• Refers: ASTM D887-08 - Standard Practices for Sampling Water-Formed Deposits
• Effective Date: 01-May-2008
• Refers: ASTM D933-84(2007) - Standard Practice for Reporting Results of Examination and Analysis of Water-Formed Deposits
• Effective Date: 01-Dec-2007
• Refers: ASTM D1129-06a - Standard Terminology Relating to Water
• Effective Date: 01-Sep-2006
• Refers: ASTM D1129-06ae1 - Standard Terminology Relating to Water
• Effective Date: 01-Sep-2006
• Refers: ASTM D1193-06 - Standard Specification for Reagent Water
• Effective Date: 01-Mar-2006
• Refers: ASTM D1129-06 - Standard Terminology Relating to Water
• Effective Date: 15-Feb-2006
• Refers: ASTM E11-04 - Standard Specification for Wire Cloth and Sieves for Testing Purposes
• Effective Date: 01-May-2004
• Refers: ASTM D1129-04 - Standard Terminology Relating to Water
• Effective Date: 01-Mar-2004

Overview

ASTM D934-22: Standard Practices for Identification of Crystalline Compounds in Water-Formed Deposits by X-Ray Diffraction, published by ASTM International, defines accepted methodologies for the qualitative identification of crystalline compounds present in water-formed deposits through X-ray diffraction (XRD) analysis. The standard addresses both the significance of identifying deposit sources and modes of deposition, which can inform strategies for deposit mitigation or removal in industrial water systems.

The document outlines two primary X-ray diffraction practices:

• Practice A-Camera-based XRD (film method)
• Practice B-Diffractometer-based XRD (electronic detection)

This standard is widely referenced in water treatment, power generation, and industrial process management for ensuring the proper analysis and control of scale and deposit formation.

Key Topics

• Purpose of Identification
  Identifying crystal structures in water-formed deposits is essential for tracing deposit origins and understanding deposition processes, enabling better control and reduction of unwanted build-up.

• Scope of Methods
  The standard provides detailed practices for analyzing powdered crystalline compounds using X-ray diffraction. Both camera and diffractometer techniques enable qualitative identification, provided suitable diffraction data exists for the compounds in question.

• Limitations

  • Amorphous phases and non-crystalline materials require special procedures and are generally not identifiable using these standard practices.
  • Oils, greases, and most organic decomposition products are not detected.
  • Sensitivity for detection varies, with qualitative identification possible for components present in concentrations ranging from 1% to 40%, depending on several sample factors.
  • Identification difficulty increases with the number of crystalline components present in the sample.

• Safety Considerations
  Operation of X-ray equipment requires stringent adherence to safety protocols to mitigate risks associated with radiation. Users must ensure all health, safety, and environmental regulations are followed according to local requirements.

Applications

The ASTM D934-22 standard is critical in the following contexts:

• Industrial Water Systems: Diagnosing and addressing mineral scale and deposit problems in boilers, cooling towers, and pipelines by identifying crystalline phases, such as calcium carbonate, gypsum, and silica.
• Power Generation: Quality control and long-term maintenance planning by monitoring water-formed deposit composition on heat exchangers and turbine equipment.
• Process Water Management: Investigating sources of fouling and scaling in manufacturing equipment to optimize water treatment protocols and reduce downtime.
• Environmental Assessment: Supporting investigations of deposit-related failures or inefficiencies in water-handling infrastructure.

Through systematic sampling, preparation, and analysis procedures, users can accurately identify deposit components and develop targeted treatment or maintenance strategies.

Related Standards

For comprehensive analysis and reporting in water-formed deposits, the following referenced ASTM standards are often used in conjunction with ASTM D934-22:

• ASTM D887 – Practices for Sampling Water-Formed Deposits
• ASTM D933 – Practice for Reporting Results of Examination and Analysis of Water-Formed Deposits
• ASTM D1129 – Terminology Relating to Water
• ASTM D1193 – Specification for Reagent Water
• ASTM D2331 – Practices for Preparation and Preliminary Testing of Water-Formed Deposits
• ASTM E11 – Specification for Woven Wire Test Sieve Cloth and Test Sieves

These standards collectively provide a robust framework for the sampling, preparation, analysis, and reporting of crystalline deposits in water systems, ensuring consistency and reliability in results.

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Keywords: ASTM D934-22, X-ray diffraction, crystalline compounds, water-formed deposits, industrial water treatment, scaling, diffractometer, camera method, deposit identification, ASTM standards, boiler scale analysis, qualitative mineral identification.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation:D934 −22
Standard Practices for
Identification of Crystalline Compounds in Water-Formed
Deposits By X-Ray Diffraction
This standard is issued under the fixed designation D934; 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 Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
1.1 These practices provide for X-ray diffraction analysis of
Barriers to Trade (TBT) Committee.
powdered crystalline compounds in water-formed deposits.
Two are given as follows:
2. Referenced Documents
Sections
Practice A—Camera 12 to 21 2.1 ASTM Standards:
Practice B—Diffractometer 22 to 30
D887 Practices for Sampling Water-Formed Deposits
1.2 Both practices yield qualitative identification of crystal- D933 Practice for Reporting Results of Examination and
line components of water-formed deposits for which X-ray
Analysis of Water-Formed Deposits
diffraction data are available or can be obtained. Greater D1129 Terminology Relating to Water
difficulty is encountered in identification when the number of
D1193 Specification for Reagent Water
crystalline components increases. D2331 Practices for Preparation and Preliminary Testing of
Water-Formed Deposits
1.3 Amorphous phases cannot be identified without special
E11 Specification for Woven Wire Test Sieve Cloth and Test
treatment. Oils, greases, and most organic decomposition
Sieves
products are not identifiable.
1.4 The sensitivity for a given component varies with a
3. Terminology
combination of such factors as density, degree of
3.1 For definitions of terms used in these practices, refer to
crystallization, particle size, coincidence of strong lines of
Terminology D1129.
components and the kind and arrangement of the atoms of the
components. Minimum percentages for identification may
4. Summary of Practices
therefore range from 1 % to 40 %.
4.1 Powdered samples are irradiated with a monochromatic
1.5 The values stated in SI units are to be regarded as
X-ray beam of short wavelength (from about 0.05 to 0.25 nm).
standard. The values listed in parenthesis are for information
The X rays interact with the atoms in the crystal and are
only.
scattered in a unique diffraction pattern which produces a
1.6 This standard does not purport to address all of the
fingerprint of the crystal’s atomic or molecular structure. The
safety concerns, if any, associated with its use. It is the
analytical instrumentation used in X-ray diffraction includes
responsibility of the user of this standard to establish appro-
the powder camera and the diffractometer (1-5).
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
5. Significance and Use
Specific precautionary statements are given in Section 8 and
5.1 The identification of the crystalline structures in water-
Note 20.
formed deposits assists in the determination of the deposit
1.7 This international standard was developed in accor-
sources and mode of deposition. This information may lead to
dance with internationally recognized principles on standard-
measures for the elimination or reduction of the water-formed
ization established in the Decision on Principles for the
deposits.
These practices are under the jurisdiction of ASTM Committee D19 on Water
and are the direct responsibility of Subcommittee D19.03 on Sampling Water and For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Water-Formed Deposits, Analysis of Water for Power Generation and Process Use, contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
On-Line Water Analysis, and Surveillance of Water. Standards volume information, refer to the standard’s Document Summary page on
Currentedition approvedJuly 1,2022.PublishedJuly 2022.Originallyapproved the ASTM website.
in 1947. Last previous edition approved in 2013 as D934 – 13, which was The boldface numbers in parentheses refer to the references listed at the end of
withdrawn in January 2022 and reinstated in July 2022. DOI: 10.1520/D0934-22. these practices.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D934−22
6. Purity of Reagents 10.1.2 Sieves—A series of sieves from No. 100 mesh
(150-µm) to No. 325 mesh (45-µm) as specified in Specifica-
6.1 Reagent grade chemicals shall be used in all tests.
tion E11.
Unless otherwise indicated, it is intended that all reagents shall
10.1.3 Soxhlet Extractor.
conform to the specifications of the Committee on Analytical
Reagents of the American Chemical Society, where such
10.2 Procedure—The following procedure is to be used in
specifications are available. Other grades may be used, pro-
preparing the sample:
vided it is first ascertained that the reagent is of sufficiently
10.2.1 Air-dry moist samples before grinding. If there is
high purity to permit its use without lessening the accuracy of
special need to preserve the nature or composition of the
the determination.
original deposit, special handling must be observed. Handle
6.2 Purity of Water—Reference to water that is used for deliquescentdepositsinadry-boxatmosphere.Handlesamples
reagent preparation, rinsing or dilution shall be understood to
subject to oxidation in an inert atmosphere.
mean water that conforms to the quantitative specifications of
10.2.2 If samples contain oil or grease, prepare a
Type I or II reagent water of Specification D1193.
chloroform-insoluble fraction by first drying the specimen for
1 h at 105 °C and then extracting for 2 h using chloroform in
7. Sampling
a Soxhlet extracting apparatus.Air-dry to remove solvent from
specimen.
7.1 Collect the sample in accordance with Practices D887.
10.2.3 Grindthesampleinamulliteoragate(mechanicalor
7.2 Asuitable amount of sample should be obtained so that
hand) mortar until approximately 98 % passes a No. 325 mesh
it is representative of the deposit under investigation.
(45-µm) sieve (see Note 1). Remove fragments of fiber, wood,
7.3 Deposits shall be removed and protected in such a way
and metal. If the specimen is not sufficiently brittle at ordinary
that they remain as nearly as possible in their original states.
temperatures to be ground to a fine powder or if it is suspected
that certain crystallites may be plastically deformed during the
8. Safety Precautions
grinding, the deposit can be subjected to dry-ice temperatures
8.1 The potential danger of high-voltage and X-ray radia-
and then ground immediately. Grind hydrated samples under
tion makes it mandatory for anyone operating X-ray apparatus
alcohol, if indicated, to prevent structural damage.
to be thoroughly familiar with basic safety precautions.
NOTE1—Mostmaterialsfoundinwater-formeddepositsaresufficiently
8.2 Place colorful signs displaying the international radia-
brittle to be reduced to 45 µm and this crystallite dimension will generally
give good identifiable diffraction patterns. However, it may not always be
tion symbol near X-ray equipment.
practical or possible to reduce certain materials to 45 µm. Often good
8.3 When X-ray equipment is producing radiation, illumi-
diffraction results can be obtained from larger crystallite sizes (No. 200
nate a conspicuous light. There should be no X rays if the bulb
mesh (75-µm) to No. 270 mesh (53-µm)). The only practical test for
proper grain size is in reproducibility of diffraction line intensities. The
burns out. Equipment without this feature can be modified.
ideal grain size may be in the subsieve range as small as 1 µm, but
8.4 Use a portable counter periodically to test for leakage of
reduction to this size may be impractical.
X rays from equipment. Lead or lead glass shielding is
sometimes needed. X rays of shorter wavelength require more
11. Selective Segregation of Analytical Sample
caution.
11.1 Chemical and Physical Treatment of Samples—
8.5 Film badges, dosimeters, or other monitoring devices
Depending on the contents of the sample, it may or may not be
shall be worn by personnel who regularly work with X-ray
necessary to concentrate or segregate components by chemical
equipment.
or physical treatment (see Note 2). Many crystalline materials
produce sharp diffraction patterns and they are identifiable
9. Preliminary Testing of Analytical Sample
when present to 1 % or 2 % in a mixture. Other substances that
9.1 It may be advantageous and even necessary to perform canbereadilyidentifiedalonearedifficulttodetectinmixtures
other analytical investigative methods to aid in the rapid evenwhentheyarepresenttotheextentof50 %.Separationof
identification of crystalline components in water-formed de- phases by density, acid solubility, or magnetic properties
posits. For other testing methods refer to Practices D2331. followed by diffraction analysis of the separated phase(s) may
help to identify various deposit components. Separation treat-
10. Preparation of Sample
ment is also helpful in resolving line coincidence in complex
mixtures. If concentration or segregation is not deemed
10.1 Apparatus—The apparatus used for preparing the
necessary, disregard any treatment and proceed in accordance
sample is as follows:
with Section 10. When treatment is necessary, use one or more
10.1.1 Mullite or Agate Mortar.
of the following chemical or physical treatments described in
11.2 to 11.7. It must be pointed out that the treatments provide
4 no absolute separation, but serve only to concentrate or
Reagent Chemicals, American Chemical Society Specifications, American
partially segregate specific components.
Chemical Society, Washington, DC. For Suggestions on the testing of reagents not
listed by the American Chemical Society, see Annual Standards for Laboratory
NOTE 2—It should be emphasized that water-formed deposits often
Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, occur in clearly defined layers and that physical separation at the time of
MD. sampling is more advantageous than later treatment.
D934−22
11.2 Water-Insoluble Fraction—This treatment removes the or less of the powdered sample into suspension. Air-dry the
water soluble from the water insoluble components. Soluble residue and regrind to pass through a No. 325 mesh (45-µm)
constituents would include most sodium, potassium, and sieve.
lithium compounds (see Note 3).
NOTE 4—A magnetic stirrer would attract any particle that was
11.2.1 Weigh 0.5 g or more of sample that has been ground
magnetic and might prevent segregation of particles of different densities.
and passed through a No. 100 mesh (150-µm) sieve. Add 100
11.6 Magnetic and Nonmagnetic Fraction—This treatment
mL of water to a beaker containing the powdered specimen.
separates the magnetic components from the nonmagnetic
Heat to boiling and then cool. Allow 30 min of reaction time,
components such as magnetite from hydroxyapatite.
filter through a 45-µm membrane filter, wash, and air-dry the
11.6.1 Weigh 0.5 g or more of sample that has been ground
residue. Regrind to pass through a No. 325 mesh (45-µm)
and passed through a No. 325 mesh (45-µm) sieve. Add 100
sieve.
mL of water to a beaker containing the powdered specimen.
NOTE 3—The filtrate may be evaporated and the residue examined by Stir with a mechanical stirrer for several minutes and then
diffraction.Although the crystalline structure may have changed from the
attachamagnettotheoutsideofthebeaker(seeNote4).While
original sample, it is often helpful in identifying simplified variations of
stirringcontinues,magneticcomponentswillbeattractedtothe
the original crystals. Sodium phosphate compounds found dispersed in
areainfrontofthemagnet,whilethenonmagneticcomponents
boiler deposits are often noncrystalline or are so complex that they are not
will remain in suspension. After 30 min, pour off the liquid
easily identified. The water soluble residue from these deposits after
evaporation is often more easily identified.
while the magnet remains in place and filter. The residue
should be essentially nonmagnetic. Remove the magnet from
11.3 Hydrochloric Acid-Insoluble Fraction—This treatment
thesideofthebeaker,rinsethemagneticportiondowntheside
removes carbonates, phosphates, and hydroxides. Partial de-
of the beaker, swirl, and filter.Air-dry the residues and regrind
composition occurs to some silicates such as serpentine,
to pass through a No. 325 mesh (45-µm) sieve.
xonotlite, and analcite. Components such as anhydrite undergo
only partial dissolution.
11.7 Brittle Fraction—This treatment concentrates the more
brittle or friable components from those that are less brittle or
11.3.1 Reagent—The reagent used for this treatment is as
follows: less friable such as calcite from silica.
11.7.1 Apparatus—The apparatus necessary for this treat-
11.3.1.1 Hydrochloric Acid(1+6)—Mix 1 volume of con-
ment is as follows:
centrated HCl (sp gr 1.19) with 6 volumes of water.
11.7.1.1 Electrical Mechanical Sieve Shaker.
11.3.2 Weigh approximately 0.5 g of the sample that has
11.7.2 Weigh 0.5 g or more of sample and hand grind in a
been ground and passed through a No. 100 mesh (150-µm)
mullite mortar until the largest particle size is approximately 1
sieve. Add 100 ml of HCl (1 + 6) to a beaker containing the
mm in diameter. Set up the sieve-shaker apparatus with four
powdered specimen. Allow 30 min of reaction time, filter
different size sieves; No. 100 mesh (150-µm), No. 140 mesh
through a membrane filter, wash and air-dry the residue.
(105-µm), No. 200 mesh (75-µm) and No. 325 mesh (45-µm).
Regrind to pass through a No. 325 mesh (45-µm) sieve.
Shake the sample for several minutes and then collect the
11.4 Nitric Acid-Insoluble Fraction—This treatment re-
various fractions from each sieve. The most friable portion of
moves all the components indicated in 11.3 in addition to
the deposit should have passed to the bottom-most sieve. Each
copper and most copper compounds.
fraction may be examined separately after regrinding to pass a
11.4.1 Reagent—The reagent used for this treatment is as
No. 325 mesh (45-µm) sieve.
follows:
PRACTICE A—CAMERA
11.4.1.1 Nitric Acid (1 + 13)—Mix 1 volume of concen-
trated HNO (sp gr 1.42) with 13 volumes of water).
12. Scope
11.4.2 Weigh 0.5 g or more of the sample which has been
ground and passed through a No. 100 mesh (150-µm) sieve.
12.1 This method covers the qualitative X-ray diffraction
Add 100 ml of HNO (1 + 13) to a beaker containing the
analysisofpowderedcrystallinesubstancesusingphotographic
powdered specimen. Allow 30 min of reaction time, filter
film as the detector. The film-camera technique has the
through a membrane filter, wash and air-dry the residue.
advantage of being less expensive initially and less costly to
Regrind to pass through a No. 325 mesh (45-µm) sieve.
maintain. The camera practice permits the use of smaller
samples.Filmcamerasdonotrequirethewell-stabilizedpower
11.5 Density Fraction—This treatment separates com-
supply as electronic detection techniques do. Often faint
pounds in water-formed deposits which differ appreciably in
diffraction lines are more readily detected with film.
density such as copper oxide and calcite.
11.5.1 Weigh 0.5 g or more of sample that has been ground
13. Summary of Practice A
and passed through a 100 mesh (150-µm) sieve. Add 100 mL
of water to a beaker containing the powdered specimen. Stir 13.1 PracticeAutilizes the Debye-Scherrer type camera. In
the liquid with a mechanical stirrer, but do not use a magnetic this method a powdered sample is placed in the center of a
stirrer (Note 4). The denser particles will settle to the bottom camera cylinder and a narrow film is wrapped around the inner
and the less dense particles will remain suspended. With wall. A monochromatic X-ray beam is directed upon the
continued stirring, withdraw sufficient liquid and filter through sample and the randomly oriented crystallites diffract the
amembranefilter.Varyingthespeedofthestirrerwillputmore incidentbeamintoasetofconcentricconesinaccordancewith
D934−22
Bragg’s Law (nλ=2d sin θ). The interceptions of the diffrac- rotating or oscillating sample, (4) a collimating system to
tion cones on the positioned film strip result in curved lines on produce a narrow and nondivergent beam, and (5) a beam stop
that film. The spacings of these lines are used to identify the or exit tube that prohibits the direct beam from exposing the
crystalline material. film or escaping into the room.
15.3 X-ray Equipment:
14. Interferences
15.3.1 X-ray Generator, with stable high-voltage electrical
14.1 Large particles in the powder mount give spotty or
supply.
discontinuous diffraction lines.Aparticle size that is too small
15.3.2 X-ray Generator Control Unit,containingthefollow-
will cause broadening of the diffraction lines.
ing: (1) a milliammeter connected across the secondary circuit
14.2 For certain elements the absorption of the X rays is to indicate current flow through the X-ray tube, ( 2) a warning
relatively high. This is especially true for the heavier elements light in full view that indicates that X rays are being produced,
when longer wavelength X rays are used (see Note 5). (3) an overload relay to trip the circuits when the tube current
Therefore, larger samples of such elements can actually give exceeds normal operating values, (4) a pressure switch in the
rise to fainter diffraction lines than would be obtained from a water line to trip the circuits if the tube receives an insufficient
smaller sample of the same element. Excessively large mounts flow of cooling water, (5) an electric timer that will shut off the
unit at the end of a preset time, (6) a time totalizer that
should be avoided if the elemental composition of the sample
has high absorption for a selected radiation. indicates the total time the generator has been on, and (7)
interlocking safety switches that turn off the high voltage
NOTE 5—Values for absorption by different elements with various
circuit if the panels of the unit are opened.
commonly-used X-ray sources can be found in the International Crystal-
lographic Tables.
15.4 Filtered Cooling Water System—Installed prior to
14.3 The proper filters should be used to remove beta X-ray equipment.
radiation and to ensure essentially monochromatic radiation
15.5 X-ray Source—Anumber of X-ray targets are available
from the target.
thatproduce K radiationofvariousdesiredwavelengths.They
α
include:Targets of chromium, iron, cobalt, copper, and molyb-
14.4 Preferred orientation of crystallites will produce dif-
fraction lines that are not of uniform intensity around the entire denum.
circumference.
16. Reagents and Material
14.5 Fluorescent radiation should be avoided if possible
16.1 Capillary Tubes—Diameter 0.1 mm to 1.0 mm thin-
since it will obscure certain diffraction lines. This radiation
walled, nonabsorbing glass or quartz. Also, fine glass fibers
may be minimized by selecting the incident-beam wavelength
0.1-mm to 0.5-mm diameter.
as far removed as possible from the K and L absorption edges
of metallic elements expected in the deposit. If a prominent
16.2 Collodion, gum tragacanth, or other suitable amor-
metallic element exists in the sample under investigation, a
phous binders.
target of the same metal should be used if possible.
16.3 Film—X-ray film with the following characteristics:
NOTE 6—Copper radiation is not as satisfactory as other recommended
(1) fine-grained texture and homogenous emulsion, (2) high
radiations for specimens containing considerable iron or iron bearing
sensitivity for the wavelength of the selected radiation, (3) low
compounds because of excessive fluorescence, which will produce fog-
fogging and low expansion due to changes in temperature and
ging on the film. However, copper targets are by far the most widely used
humidity. The film should be of the screenless type (see Note
and most generally applicable.
8). All film should be handled and processed in accordance
15. Apparatus
with manufacturer’s recommendations.
15.1 Beta Filters—Free metals or metal oxides filters of
NOTE 8—If molybdenum radiation is used, a screen-type film with the
vanadium, manganese, iron, nickel, and zirconium. For the
fluorazure type intensifying screen may be used.
choice of filter refer to the following list (see Note 7):
17. Preparation of Test Specimen
X-ray Target Material Filter
Chromium Vanadium
17.1 Prepare the powdered specimens in such a shape or
Iron Manganese
form as required by the camera used.
Cobalt Iron
Copper Nickel
17.2 Common Mounts:
Molybdenum Zirconium
17.2.1 Rod Mount—A few milligrams of the powdered
NOTE 7—The filter shall be of sufficient thickness to reduce the
sample are mixed with an amorphous binder such as collodion
intensity of the K radiation to 1/100 of the K radiation. Monochromator
β α
or gum tragacanth and rolled into a rod 0.1-mm to 1.0-mm
crystal attachments are available for many cameras which will eliminate
diameter.
the use of beta filters and produce clean diffraction lines corresponding to
a single X-ray wavelength with low background. 17.2.2 Coated Glass Fiber Mount—A fine glass fiber is
dipped in collodion or some amorphous glue and rolled in the
15.2 Camera, Debye-Scherrer type usually 57.3 mm or
114.6 mm in diameter so that 1 mm of film equals 2 or 1 degs,
respectively. Features of the camera should include: (1)a
The equipment listed is generally sold as a package by most manufacturers of
device to hold film flush against the cylinder, (2) a sample
X-ray diffractometers. The International Union of Crystallography (I.C.Cr.) pub-
holder with provision to center the mount, (3) a device for lishes an Index of Crystallographic Supplies and lists various suppliers.
D934−22
prevent a gassy condition, cleaning the cooling water screens to prevent
powdered sample to coat the outer cylindrical surface. Photo-
flow blockage, carefully cleaning electrical contacts to make a good
graphsmadewithglassfibersusuallyshowoneortwodiffused
electrical contact, and gentle handling.
halos at about 0.42 nm (see Note 9).
19.3 LoadwithfilmandmountthecameraontheX-rayunit
17.2.3 Capillary Mount—Small diametered nonabsorbing
in front of the X-ray tube window in such a manner as to
glass tubes can be filled with the powdered sample and then
produce a strong, uniform beam through the collimating
compacted by dropping through a 0.3-mm to 0.6-m (1-ft to
system. Shield the other tube windows to protect the operator
2-ft)lengthofsmalldiameterglasstubing.Thecapillarycanbe
and prevent stray radiation from fogging the film during
sealed with wax if desired to prevent hydration, oxidation, or
exposure.
carbonation (see Note 9).
17.2.4 Ball Mount—Asmall amount of powdered sample is
NOTE 14—There are several types of film loading in Debye-Scherrer
mixed with collodion and rolled into a ball and then glued onto
cameras, including Bradley-Jay, Van Arkle, Straumanis, and Wilson. The
Straumanis method, which is the most popular, contains mounting holes
a small glass fiber.
for both the beam catcher and collimator.
17.2.5 Wedge Mount—The powdered sample is pressed into
a wedge-shaped cavity which can be supported without a 19.4 Be sure all requirements specified by the manufacturer
binder. have been fulfilled and that all safety precautions have been
taken before ac
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