ASTM E588-03(2020)

Standard Practice for Detection of Large Inclusions in Bearing Quality Steel by the Ultrasonic Method

SIGNIFICANCE AND USE
6.1 Comparison with Other Inclusion Rating Methods—Because the test is performed on a volumetric rather than a surface-examination basis, the ultrasonic method is inherently better able to detect infrequently occurring large inclusions or clusters of small inclusions than eddy current, magnetic particle, microscopical, or macroscopic examination procedures.  
6.2 Limitation of Inclusion Size and Type—A limitation of the method is that it will not detect all inclusions. Inclusion chemistry, size, shape, location, and distribution may limit the ability of the method to provide indications distinct from those generated by the surrounding metallurgical structure. The recommended practice is only meaningfully applicable to examination of steel wherein the inclusion size and type are within the detection capabilities of the method. For steel wherein inclusion size, dispersion, and chemistry prevent optimum inclusion detection by ultrasonics, microscopical methods detailed in Test Methods E45 may be applied.
SCOPE
1.1 This practice covers a procedure for the rating of rectangular steel sections by immersion ultrasonic techniques. Its purpose is to provide information on the content of large inclusions or clusters of small inclusions for determining the suitability of a steel lot for bearing applications. This practice in no manner defines or establishes limits of acceptability.  
1.2 For this document, large inclusions are defined in ultrasonic terms as those having a reflecting area equivalent to or larger than a 1/64 in. diameter flat-bottom hole in a steel reference block of similar properties and thickness. In metallographic terms, large inclusions, defined in this way, are of approximately the same size as the smallest detectable sizes revealed by the macroscopic methods of Test Methods E45. In some cases, inclusions smaller than those described previously can be detected either individually or in clusters, depending on their type, chemical composition, orientation to the ultrasonic beam and distance from the sound entry surface of the specimen.  
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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 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: 29-Feb-2020
• ICS: 77.040.20 - Non-destructive testing of metals
• Technical Committee: A01 - Steel, Stainless Steel and Related Alloys
• Drafting Committee: A01.28 - Bearing and Power Transmission Steels

Relations

• Replaces: ASTM E588-03(2014) - Standard Practice for Detection of Large Inclusions in Bearing Quality Steel by the Ultrasonic Method
• Effective Date: 01-Mar-2020
• Refers: ASTM E1316-24 - Standard Terminology for <?Pub Dtl?>Nondestructive Examinations
• Effective Date: 01-Feb-2024
• Refers: ASTM E45-18a(2023) - Standard Test Methods for Determining the Inclusion Content of Steel
• Effective Date: 01-Nov-2023
• Refers: ASTM E1316-19b - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Dec-2019
• Refers: ASTM E1316-19 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Mar-2019
• Refers: ASTM E1316-18 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Jan-2018
• Refers: ASTM E1316-17a - Standard Terminology for Nondestructive Examinations
• Effective Date: 15-Jun-2017
• Refers: ASTM E1316-17 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Feb-2017
• Refers: ASTM E1316-16a - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Aug-2016
• Refers: ASTM E1316-16 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Feb-2016
• Refers: ASTM E1316-15a - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Dec-2015
• Refers: ASTM E1316-15 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Sep-2015
• Refers: ASTM E1316-14 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Jun-2014
• Refers: ASTM E1316-14e1 - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Jun-2014
• Refers: ASTM E1316-13d - Standard Terminology for Nondestructive Examinations
• Effective Date: 01-Dec-2013

Overview

ASTM E588-03(2020), titled Standard Practice for Detection of Large Inclusions in Bearing Quality Steel by the Ultrasonic Method, is an international standard developed by ASTM International. This standard outlines a procedure for the ultrasonic testing and rating of rectangular steel sections to detect large non-metallic inclusions or clusters of small inclusions. These inclusions can affect the quality and performance of bearing steels used in critical applications. The practice provides valuable information for assessing the suitability of steel lots for bearing applications, using a volumetric immersion ultrasonic inspection that offers advantages over traditional surface examination methods.

Key Topics

• Ultrasonic Testing of Bearing Steel: Employs pulsed longitudinal waves in an immersion testing setup to detect inclusions within steel sections, covering both individual large inclusions and clusters of smaller inclusions.
• Comparison to Other Methods: Volumetric ultrasonic inspection is more effective at identifying infrequently occurring large inclusions compared to eddy current, magnetic particle, and optical methods, which are surface-based.
• Measurement Criteria: Large inclusions are defined in terms of their ability to reflect ultrasonic waves, equivalent to or larger than a 1/64 in. diameter flat-bottom hole in a steel reference block of similar properties.
• Instrumentation: Specifies the required ultrasonic equipment features, such as search units, calibration blocks, immersion tanks, and recording devices to ensure consistent and accurate results.
• Test Procedures: Covers sample preparation, calibration, scanning direction, sensitivity adjustments, and calculation of cleanliness severity ratings for steel lots.
• Limitations: The method may not detect all inclusions, as factors like chemical composition, inclusion size, shape, and location relative to the ultrasonic beam affect detectability.
• Personnel and Agency Qualification: Stresses the importance of qualified personnel and agencies, referencing standards like ASNT SNT-TC-1A and CP-189 for nondestructive testing (NDT) competence.

Applications

• Quality Assurance in Bearing Steel Manufacturing: Used extensively to ensure the cleanliness and reliability of bearing quality steels, especially for applications where performance under load is critical.
• Supplier-Purchaser Agreements: Provides a standardized basis for steel makers and customers to agree on the assessment of large inclusions and the acceptance or rejection of steel lots.
• Process Improvement: Enables continuous improvement in steel production and processing by identifying and reducing sources of harmful inclusions.
• Alternative to Surface-Based Methods: Offers a solution when traditional methods underperform, especially for detecting subsurface inclusions that might not manifest at the surface.
• Complementary Testing: When ultrasonics are unsuitable due to material characteristics, metallographic techniques, such as ASTM E45, may be used for a fuller analysis.

Related Standards

• ASTM E45: Test Methods for Determining the Inclusion Content of Steel – Focuses on microscopic and macroscopic analysis of steel inclusions, often used as a supplementary or alternative assessment.
• ASTM E543: Specification for Agencies Performing Nondestructive Testing – Ensures organizational competence in NDT operations.
• ASNT SNT-TC-1A and CP-189 – Guidelines for qualification and certification of NDT personnel, ensuring correct execution of testing procedures.
• ASTM E1316: Terminology for Nondestructive Examinations – Provides standard nomenclature for clarity in NDT practices.

Practical Value

Implementing ASTM E588-03(2020) helps manufacturers, suppliers, and users of bearing steel to achieve consistent, high-quality material. The ultrasonic method improves the reliability of detecting critical large inclusions, supporting robust supply chain quality assurance and contributing to the performance and longevity of products that depend on superior bearing steel cleanliness. By adhering to this standard, stakeholders can reduce the risk of bearing failure caused by non-metallic inclusions, optimize inspection processes, and meet stringent industry requirements for nondestructive testing in steel manufacturing.

Keywords: ultrasonic testing, bearing steel cleanliness, large inclusions detection, ASTM E588, nondestructive evaluation, steel quality assurance, volumetric inspection, inclusion rating

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: E588 − 03 (Reapproved 2020)
Standard Practice for
Detection of Large Inclusions in Bearing Quality Steel by
the Ultrasonic Method
This standard is issued under the fixed designation E588; 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 2. Referenced Documents
2.1 ASTM Standards:
1.1 This practice covers a procedure for the rating of
E45Test Methods for Determining the Inclusion Content of
rectangular steel sections by immersion ultrasonic techniques.
Steel
Its purpose is to provide information on the content of large
E214Practice for Immersed Ultrasonic Testing by the Re-
inclusions or clusters of small inclusions for determining the
flection Method Using Pulsed Longitudinal Waves (With-
suitability of a steel lot for bearing applications. This practice
drawn 2007)
in no manner defines or establishes limits of acceptability.
E428Practice for Fabrication and Control of Metal, Other
1.2 For this document, large inclusions are defined in
than Aluminum, Reference Blocks Used in Ultrasonic
ultrasonic terms as those having a reflecting area equivalent to
Testing (Withdrawn 2019)
or larger than a ⁄64 in. diameter flat-bottom hole in a steel
E543Specification forAgencies Performing Nondestructive
reference block of similar properties and thickness. In metal-
Testing
lographic terms, large inclusions, defined in this way, are of
E1316Terminology for Nondestructive Examinations
approximately the same size as the smallest detectable sizes
2.2 ASNT Documents:
revealed by the macroscopic methods ofTest Methods E45.In
SNT-TC-1ARecommended Practice for Personnel Qualifi-
some cases, inclusions smaller than those described previously 4
cation and Certification in Nondestructive Testing
can bedetectedeither individually or in clusters, dependingon
ASNT-CP-189Standard for Qualification and Certification
their type, chemical composition, orientation to the ultrasonic 4
of Nondestructive Testing Personnel
beam and distance from the sound entry surface of the
specimen.
3. Terminology
1.3 This standard does not purport to address all of the
3.1 Definitions—For definitions of terms used in this
safety concerns, if any, associated with its use. It is the practice, see Terminology E1316.
responsibility of the user of this standard to establish appro-
4. Basis of Application
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
4.1 Agreements Between Using Parties—In order for this
1.4 This international standard was developed in accor- practice to be effectively used, the following items require
dance with internationally recognized principles on standard- agreement between the using parties.
ization established in the Decision on Principles for the 4.1.1 Evaluation of Nondestructive Testing Agencies—An
Development of International Standards, Guides and Recom- agreement is required as to whether the nondestructive testing
mendations issued by the World Trade Organization Technical agency, as defined in Specification E543, must be formally
Barriers to Trade (TBT) Committee.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
This practice is under the jurisdiction of ASTM Committee A01 on Steel, Standards volume information, refer to the standard’s Document Summary page on
Stainless Steel and RelatedAlloys and is the direct responsibility of Subcommittee the ASTM website.
A01.28 on Bearing and Power Transmission Steels. The last approved version of this historical standard is referenced on
Current edition approved March 1, 2020. Published March 2020. Originally www.astm.org.
approvedin1976.Lastpreviouseditionapprovedin2014asE588–03(2014).DOI: AvailablefromAmericanSocietyforNondestructiveTesting(ASNT),P.O.Box
10.1520/E0588–03R20. 28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http://www.asnt.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E588 − 03 (2020)
evaluated and qualified to perform the examination. If such an individual reflections may have different phase characteristics
evaluation is specified, a documented procedure such as when arriving at the search unit if the travel distances are
Specification E543 shall be used as the basis for evaluation. different.
4.1.2 Personnel Qualification—Nondestructive testing
8. Apparatus
(NDT) personnel shall be qualified in accordance with a
nationally recognized NDT personnel qualification practice or 8.1 Equipment Required—An equipment system with the
standard such as ASNT CP-189, SNT-TC-1A, or a similar followingcomponentsisneededtoconductthistest:ultrasonic
document. The practice or standard used and its applicable test instrument, search unit, a means of recording signals of
revision shall be specified in the contractual agreement be- various amplitudes, a system reference block, instrument
tween the using parties. calibration block, and an immersion tank with suitable scan-
ning accessories.
4.1.3 Search Unit Performance Tests—Annex A1 defines
the minimum manufacturer’s specifications for search units to
8.2 Ultrasonic Instrument—The ultrasonic instrument shall
beusedwiththispractice.Theextentoftestingandverification
be capable of generating and receiving electrical pulses of 10
of these parameters to be performed by the manufacturer shall
MHzfrequencyatlevelscompatiblewiththetestrequirements.
be specified in the contractual agreement between the using
It shall have both an A-scan presentation and an analog or
parties.
digital output. It shall be the ultrasonic instrument manufac-
turer’sresponsibilitythatinstrumentssuppliedforusewiththis
5. Summary of Practice
test meet the minimum requirements delineated in this recom-
mended practice.
5.1 The general technique used is immersion ultrasonic
8.2.1 Receiver Characteristics—The center frequency shall
testing by the reflection method using pulsed longitudinal
be 10 MHz 6 0.5 MHz. The bandpass of the receiver shall be
waves such as described in Practice E214. Specific additional
at least 1.3 MHz (3 dB points).
requirements for sample preparation, equipment operating
8.2.2 Dynamic Range—The dynamic range of the instru-
parameters and calibration, and expression of results are
ment shall permit detection of steel balls with a 16 to 1
delineated in this procedure. Special focused search units
diameter ratio at a given sensitivity. Balls shall be placed in
having operating characteristics as defined in Annex A1 are
wateratthefocalpointofthesearchunit.Eachsizeballwithin
required.
this range shall give a significantly different amplitude of
indication.
6. Significance and Use
8.2.3 Stability—The signal amplitude of a usable full-scale
6.1 Comparison with Other Inclusion Rating Methods—
indication shall not vary more than 5% after1hof instrument
Because the test is performed on a volumetric rather than a
warm-up, and preferably by less than 2% (4 h test with air
surface-examination basis, the ultrasonic method is inherently
temperaturebeingheldto 61.2°Coveratemperaturerangeof
better able to detect infrequently occurring large inclusions or
17.5°C to 25.5°C).
clusters of small inclusions than eddy current, magnetic
8.2.4 Sweep Length and Linearity—Sweep length of oscil-
particle, microscopical, or macroscopic examination proce-
loscope presentation shall be capable of being adjusted to
dures.
represent 1 mm=1.27 mm of steel. A minimum of 80 mm of
the sweep display shall be linear to within 5% of full scale.
6.2 Limitation of Inclusion Size and Type—A limitation of
The signal amplitude of an indication from a target shall not
the method is that it will not detect all inclusions. Inclusion
vary more than 64% over the gated portion of the sweep
chemistry, size, shape, location, and distribution may limit the
employed in calibration and testing.
ability of the method to provide indications distinct from those
8.2.5 Repetition Rate—Therepetitionrateofthepulsershall
generated by the surrounding metallurgical structure. The
not be less than 500 pulses per second.
recommended practice is only meaningfully applicable to
examination of steel wherein the inclusion size and type are 8.3 Search Units—Ultrasonic search units for this test shall
within the detection capabilities of the method. For steel be spherically focused immersion-type units. Uniform perfor-
wherein inclusion size, dispersion, and chemistry prevent mance characteristics of search units are critical for obtaining
optimum inclusion detection by ultrasonics, microscopical reproducible test measurements. (See AnnexA1, which delin-
methods detailed in Test Methods E45 may be applied. eates search unit performance characteristics to be met by
search unit manufacturers.) Performance characteristics of
7. Interference searchunitsrequiringconsiderationare:theuniformityoffocal
distance in water, center frequency, frequency spectrum, lens
7.1 Reflections from Multiple Inclusions—An ultrasonic in-
radius, width of field, and beam symmetry.
dication can represent the reflection from a single inclusion;
8.3.1 Focal Length—Afocused beam of radiated ultrasonic
however, it typically represents the vector summation of
energy is recommended to provide lateral resolution of small
reflections from clusters of small inclusions contained within a
defectsandtoimprovetestingsensitivityintheregionnearthe
volume of a few cubic millimetres.
focal point. The focal length of a search unit is defined in this
7.2 Response as a Function of Inclusion Type—The indi- discussion as the distance in water, on the search unit axis,
vidual inclusion reflections can have different amplitudes between the search unit and the surface of a ⁄2 in. or 12 mm
because of different inclusion characteristics. In addition, the diameter ball target at which the highest reflection amplitude
E588 − 03 (2020)
indication is obtained. Different focal length transducers may various amplitude indications. These include level counters,
beusedtoobtainoptimumresponseatselecteddistancesbelow pulse counters, integrators, strip chart recorders, B-scan
the test sample surface. (Variation of search unit-to-specimen recorders, C-scan recorders, memory oscilloscopes, and com-
surface water path would also affect the focal point within the puter techniques. With pulse counters, both repetition rate and
test sample.) scanning speed must be held within a 5% tolerance and,
8.3.2 Search Unit Characteristics—Search units generally preferably, 2%.
employed have the following frequency and focal length as
8.6 System Reference Block—A system reference block
purchased:
(defined dimensionally in Section 9.2) is required for initial
Frequency Focal Length in Water
adjustments and operational testing of the equipment. This
10 ± 0.5 MHz 8.2 ± 0.3 in. (208.3 ± 7.6 mm)
sample should be selected to provide reflection signals at all
8.3.3 Beam Symmetry—Each search unit should be rotated
countinglevels.Depthdistributionofinclusionsintheselected
on its ultrasonic beam axis (not necessarily geometric axis)
reference block should make its response characteristics rela-
until a particular circumferential orientation is found which
tively insensitive to minor focal length variations between
givesamaximumseverity,orcount,fromthesystemreference
different search units. The reference block should give a
block. This search unit orientation shall be identified and
minimum change in total counts of 10% for each 10%
employed in subsequent tests. Search units that exhibit varia-
increase or decrease in amplitude setting.Amaximum of 30%
tions in indication amplitude in excess of 15% during rotation
change in count for each 10% change in amplitude setting
shallnotbeconsideredsatisfactoryforthetest.Thereareother
should not be exceeded. It should be suitably protected from
methods, such as optimum response over a precision and
corrosion to assure its longevity.
uniform taut wire, that have been found to be usable.
9. Test Specimens
8.3.4 Performance—The performance capabilities of all
new search units shall be verified by an actual test on the
9.1 General—Test specimens must be either in the rolled or
systemreferenceblock.Thedataobtainedfornewsearchunits
forged condition. If forged, upset forging is prohibited in order
should be compared with that obtained for other search units
to maintain the rolling direction. Care should be taken not to
having the same specifications and tested under identical
overheat the forging to avoid spurious ultrasonic indications.
conditions.
Specimen location and frequency shall be as agreed upon
between the supplier and the purchaser.
8.4 Immersion Tank and Accessories— An immersion tank
with associated scanning and indexing facilities shall be used.
9.2 Specimen Size and Shape—Specimens shall have a
8.4.1 Search Unit Angulation—The tank shall be provided
minimumcross-sectionaldimensionafterpreparationof3 ⁄2in.
with a manipulator capable of continuously angulating the
(88.9 mm). The area scanned shall be sufficient to permit
3 3
search unit in two vertical mutually perpendicular planes
testingofaminimumof25in. (410cm )ofthespecimen.The
permitting the required normalization.
tested volume equals the scanned area multiplied by the gated
8.4.2 Scanning and Indexing—The tank bridge and carriage
depth.Ifspecialconsiderationisgiven,thinnersamplesmaybe
assemblies shall provide X-Y motion to the search unit. The
tested.
scanning shall be parallel or perpendicular (depending on the
9.3 Entry Surface Finish—The test surface through which
procedure) to the test specimen axis and the indexing shall be
the sound enters the specimen shall be machined and ground.
perpendicular to the scanning.
Thisfinishinanydirectionoverthesurfaceshallbepreferably
8.4.3 Test Specimen Mounting—The tank shall be provided
10 µin. to 80 µin. (0.25 µm to 2.0 µm). Final material removal
with fixturing permitting the mounting of the entry surface of
may require a dressed grinding wheel to avoid spurious,
the test specimen parallel to the bridge travel so that the
near-surface indications. All four sides are to be ground.
distance between search unit and specimen remains constant
within 6 ⁄64 in. (0.4 mm). 9.4 Heat Treatment—Thermal conditioning of the speci-
mens is required to minimize acoustic anomalies. Typical heat
8.4.4 Couplant:
8.4.4.1 The inspection solution shall consist of tap or treatment may consist of normalizing or quenching and
tempering, depending on steel type, to meet the ultrasonic
distilled water to which a wetting agent has been added to
disperse air bubbles. The pH of the water shall be maintained penetrability requirement of Section 9.5. Certain steels may
1 1
require special thermal treatment such as a double temper to
within 7 ⁄2 to 8 ⁄2. Rust preventives may also be added. All
chemical additives shall be held within concentrations that do obtain suitable acoustic properties.
not adversely affect test performance. Water temperature must
9.5 Ultrasonic Penetrability—The ultrasonic penetrability
be held between 19.5°C and 25.5°C. It is important that
shall be determined to be suitable for the inspection. The
excessive thermal gradients do not exist between the search
penetrability is acceptable if the third back reflection of the
unit and the calibration standards.
specimen is 25% of full screen height, over the center of the
8.4.4.2 A means of circulating the immersion inspection
billet specimen, at standard test conditions and test sensitivity.
solution shall be employed, when necessary, to dissipate
thermal gradients. 10. Procedure
8.5 Readout Equipment—Various types of instrumentation 10.1 General:
havebeenemployedinconjunctionwithultrasonicinstruments 10.1.1 Operating Frequency—The operating frequency for
for many years to determine the number of occurrences of mostbearingsteelsis10MHz.Tenmegahertzisrecommended
E588 − 03 (2020)
as the highest practical frequency available within existing 10.2.1 Special Equipment and Accessories:
manufacturing capabilities to produce search units with uni-
10.2.1.1 Athree-level pulse counter having separate adjust-
form performance characteristics. Higher frequencies give
able thresholds for each level shall be used to determine the
better resolution, while lower frequencies give better penetra-
number of occurrences of various amplitude indications. The
tion.
inputcircuitstothecountersshallemploysufficientfilteringto
10.1.2 Normalizing Search Unit—Normalizing the search
eliminate counter operation from extraneous high-frequency
unit beam to the entry surface is a precise adjustment and
signals. The equipment shall have sufficient hysteresis to
requires extreme care. Normalizing can be accomplished over
prevent counting spurious variations (jitter).
billet specimens with parallel ground sides by adjusting for a
10.2.2 Calibration Standards:
maximum first far field back reflection in an area where no
10.2.2.1 Counter calibration requires a set of three ball
material discontinuities are present to distort the ultrasonic
targets with size ratio of 12:7:4. Highly polished stainless steel
beam. An alternative method that has been found useful is to
ball sets with a surface roughness of 2 µin. (0.05 mm) Ra
maximize the far field reflections from a hardened steel plate
3 7 1
maximum and with diameters of ⁄4 in., ⁄16 in., and ⁄4 in., or
with parallel ground sides, such as a 58 to 64 HRC hardness
12mm, 7 mm, and 4 mm, may be employed. (A ⁄2 in. ball is
test block, placed on top of the ground billet surface.
an acceptable substitute for the ⁄16 in. ball.)
10.1.3 Water Distance—The water distance between the
search unit and entry surface shall not be less than 1 in. 6 ⁄16 10.2.2.2 Test instrument calibration is performed with a 10
in.(25.4mm 61.6mm)forevery4in.(102mm)ofspecimen mm hemispherically shaped hole instrument calibration block
thickness. In no case should the water distance be less than 1 described in Annex A2. This reference target shall be 1.7in.
6 ⁄16 in. (43.2 mm) below the entry surface of the standard.
10.1.4 Monitoring Gates—Either single or multiple gates
10.2.2.3 A system reference block specified in 8.6 shall be
may be employed.
employed to verify instrument calibration and to cross refer-
10.1.5 Scanning of Specimen—Scanning of the specimen
ence equi
...