ASTM E768-99(2004)
(Practice)Standard Guide for Preparing and Evaluating Specimens for Automatic Inclusion Assessment of Steel
Standard Guide for Preparing and Evaluating Specimens for Automatic Inclusion Assessment of Steel
SCOPE
1.1 This guide covers two preparation methods for steel metallographic specimens that will be analyzed for nonmetallic inclusions with automatic image analysis (AIA) equipment. The two methods of preparation are offered as accepted methods used to retain nonmetallic inclusions in steel. This guide does not limit the user to these methods.
1.2 A procedure to test the suitability of the prepared specimen for AIA inclusion work, using differential interference contrast (DIC), is presented.
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:E768–99 (Reapproved 2004)
Standard Guide for
Preparing and Evaluating Specimens for Automatic
1
Inclusion Assessment of Steel
This standard is issued under the fixed designation E 768; 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 charged with an abrasive (usually 6 to 15-µm diamond par-
2
ticles), and used as the fine grinding operation in a metallo-
1.1 This guide covers two preparation methods for steel
graphic preparation procedure.
metallographicspecimensthatwillbeanalyzedfornonmetallic
inclusions with automatic image analysis (AIA) equipment.
4. Significance and Use
The two methods of preparation are offered as accepted
4.1 Inclusion ratings done either manually using Test Meth-
methods used to retain nonmetallic inclusions in steel. This
ods E 45 or automatically using Practice E 1122 or E 1245 are
guide does not limit the user to these methods.
influenced by the quality of specimen preparation. This guide
1.2 A procedure to test the suitability of the prepared
provides examples of proven specimen preparation methods
specimen for AIA inclusion work, using differential interfer-
that retain inclusions in polished steel specimens.
ence contrast (DIC), is presented.
4.2 This guide provides a procedure to determine if the
2. Referenced Documents prepared specimens are of suitable quality for subsequent
3 rating of inclusions. None of these methods should be con-
2.1 ASTM Standards:
strued as defining or establishing specific procedures or limits
E 3 Practice for Preparation of Metallographic Specimens
of acceptability for any steel grade.
E 7 Terminology Relating to Metallography
E 45 Test Methods for Determining the Inclusion Content
5. Preparation Methods
of Steel
5.1 Background:
E 883 Guide for Reflected-Light Photomicrography
5.1.1 The inclusions in the plane of polish must be fully
E 1122 Practice for Obtaining JK Inclusion Ratings Using
preserved and clearly visible. Preparation should not produce
Automatic Image Analysis
excessive relief around the perimeter of the inclusions that
E 1245 Practice for Determining the Inclusion or Second-
would exaggerate the size and number of inclusions on the
Phase Constituent Content of Metals by Automatic Image
plane of polish. In many cases, the preparation of specimens
Analysis
for inclusion rating is more readily performed after the
3. Terminology specimens have been hardened by a suitable heat treatment
procedure (austenize, quench to fully martensitic structure,
3.1 Definitions:
temper at a relatively low temperature).
3.1.1 For definitions used in this practice, refer to Termi-
5.1.2 Cleanliness is an important consideration in all stages
nology E 7.
of specimen preparation.
3.1.2 differential interference contrast microscopy—a com-
5.1.2.1 Heat-treated specimens should be wire brushed or
prehensive definition appears in Guide E 883, paragraph 11.8.
shot blasted or have the surface ground to remove adherent
3.2 Definitions of Terms Specific to This Standard:
scale.
3.2.1 rigid grinding disk—a non-fabric support surface,
5.1.2.2 After completing the grinding steps and before
such as a composite of metal/ceramic or metal/polymer,
performing the polishing steps, the specimens and specimen
holders must be cleaned to prevent contamination of the next
1
This test method is under the jurisdiction of ASTM Committee E04 on
preparationstep.Cleaningthespecimensandspecimenholders
MetallographyandisthedirectresponsibilityofSubcommitteeE04.01onSampling
between each grinding step can eliminate contamination of
Specimen Preparation, and Photography.
coarse abrasives to the following finer preparation step.
Current edition approved Nov. 1, 2004. Published November 2004. Orignally
approved in 1999. Last previous edition approved in 1999 as E 768–99. 5.1.2.3 After the preparation is complete, swab the surface
2
Supporting data have been filed at ASTM International Headquarters and may
carefully with cotton and a water/soap solution containing a
be obtained by requesting Research Report RR: E04–1002.
corrosion inhibitor such as a machine coolant or ethyl alcohol
3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
solution to remove any films or other debris that would
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
interfere with the inclusion rating.
the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1
---------------------- Page: 1 ------------
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.