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ASTM E1268-01

(Practice)

Standard Practice for Assessing the Degree of Banding or Orientation of Microstructures

Standard Practice for Assessing the Degree of Banding or Orientation of Microstructures

SCOPE
1.1 This practice describes a procedure to qualitatively describe the nature of banded or oriented microstructures based on the morphological appearance of the microstructure.
1.2 This practice describes stereological procedures for quantitative measurement of the degree of microstructural banding or orientation.
Note 1—Although stereological measurement methods are used to assess the degree of banding or alignment, the measurements are only made on planes parallel to the deformation direction (that is, a longitudinal plane) and the three-dimensional characteristics of the banding or alignment are not evaluated.
1.3 This practice describes a microindentation hardness test procedure for assessing the magnitude of the hardness differences present in banded heat-treated steels. For fully martensitic carbon and alloy steels (0.10-0.65 %C), in the as-quenched condition, the carbon content of the matrix and segregate may be estimated from the microindentation hardness values.
1.4 This standard does not cover chemical analytical methods for evaluating banded structures.
1.5 This practice deals only with the recommended test methods and nothing in it should be construed as defining or establishing limits of acceptability.
1.6 The measured values are stated in SI units, which are regarded as standard. Equivalent inch-pound values, when listed, are in parentheses and may be approximate.
1.7 This standard does not purport to address all of the safety problems, 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

Status
Historical
Publication Date
09-Dec-2001
ICS
07.030 - Physics. Chemistry
Technical Committee
E04 - Metallography
Drafting Committee
E04.14 - Quantitative Metallography
Current Stage
Ref Project

Relations

Replaces
ASTM E1268-99 - Standard Practice for Assessing the Degree of Banding or Orientation of Microstructures
Effective Date
10-Dec-2001
Referred By
ASTM E3-11(2017) - Standard Guide for Preparation of Metallographic Specimens
Effective Date
10-Dec-2001
Referred By
ASTM A354-17e2 - Standard Specification for Quenched and Tempered Alloy Steel Bolts, Studs, and Other Externally Threaded Fasteners
Effective Date
10-Dec-2001
Referred By
ASTM G209-14(2022) - Standard Practice for Detecting mu-phase in Wrought Nickel-Rich, Chromium, Molybdenum-Bearing Alloys
Effective Date
10-Dec-2001
Referred By
ASTM E384-22 - Standard Test Method for Microindentation Hardness of Materials
Effective Date
10-Dec-2001

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ASTM E1268-01 - Standard Practice for Assessing the Degree of Banding or Orientation of Microstructures
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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: E 1268 – 01
Standard Practice for
Assessing the Degree of Banding or Orientation of
1
Microstructures
This standard is issued under the fixed designation E 1268; 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.
INTRODUCTION
Segregation occurs during the dendritic solidification of metals and alloys and is aligned by
subsequent deformation. Solid-state transformations may be influenced by the resulting microsegre-
gation pattern leading to development of a layered or banded microstructure. The most common
example of banding is the layered ferrite-pearlite structure of wrought low-carbon and low-carbon
alloy steels. Other examples of banding include carbide banding in hypereutectoid tool steels and
martensite banding in heat-treated alloy steels. This practice covers procedures to describe the
appearance of banded structures, procedures for characterizing the extent of banding, and a
microindentation hardness procedure for determining the difference in hardness between bands in heat
treated specimens. The stereological methods may also be used to characterize non-banded
microstructures with second phase constituents oriented (elongated) in varying degrees in the
deformation direction.
1. Scope 1.5 This practice deals only with the recommended test
methods and nothing in it should be construed as defining or
1.1 This practice describes a procedure to qualitatively
establishing limits of acceptability.
describethenatureofbandedororientedmicrostructuresbased
1.6 The measured values are stated in SI units, which are
on the morphological appearance of the microstructure.
regarded as standard. Equivalent inch-pound values, when
1.2 This practice describes stereological procedures for
listed, are in parentheses and may be approximate.
quantitative measurement of the degree of microstructural
1.7 This standard does not purport to address all of the
banding or orientation.
safety problems, if any, associated with its use. It is the
NOTE 1—Although stereological measurement methods are used to
responsibility of the user of this standard to establish appro-
assess the degree of banding or alignment, the measurements are only
priate safety and health practices and determine the applica-
madeonplanesparalleltothedeformationdirection(thatis,alongitudinal
bility of regulatory limitations prior to use.
plane) and the three-dimensional characteristics of the banding or align-
ment are not evaluated.
2. Referenced Documents
1.3 This practice describes a microindentation hardness test
2.1 ASTM Standards:
procedure for assessing the magnitude of the hardness differ-
A 370 Test Methods and Definitions for MechanicalTesting
ences present in banded heat-treated steels. For fully marten-
2
of Steel Products
sitic carbon and alloy steels (0.10–0.65 %C), in the as-
A 572/A 572M Specification for High-Strength Low-Alloy
quenched condition, the carbon content of the matrix and
3
Columbium-Vanadium Structural Steel
segregate may be estimated from the microindentation hard-
A 588/A 588M Specification for High-Strength Low-Alloy
ness values.
Structural Steel with 50 ksi [345 MPa] Minimum Yield
1.4 This standard does not cover chemical analytical meth-
3
Point to 4 in. [100 mm] Thick
ods for evaluating banded structures.
4
E3 Methods of Preparation of Metallographic Specimens
4
E7 Terminology Relating to Metallography
4
E 140 Hardness Conversion Tables for Metals
1
This practice is under the jurisdiction of ASTM Committee E04 on Metallog-
raphy and is the direct responsibility of Subcommittee E04.14 on Quantitative
2
Metallography. Annual Book of ASTM Standards, Vol 01.03.
3
Current edition approved Dec. 10, 2001. Published February 2002. Originally Annual Book of ASTM Standards, Vol 01.04.
4
published as E 1268 – 88. Last previous edition E 1268 – 99. Annual Book of ASTM Standards, Vol 03.01.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1

---------------------- Page: 1 ----------------------
E1268–01
NOTE 1—The test grid lines have been shown oriented perpendicular (A) to the deformation axis and parallel (B) to the deformation axis. The counts
for N , N , P , and P are shown for counts made from top to bottom (A) or from left to right (B).
' || ' ||
NOTE 2—T indicates a tangent hit and E indicates that the grid line ended within the particle; both situations are handled as shown.
FIG. 1 Illustration of the Counting of Particle Interceptions (N) and Boundary Intersections (P) for an Oriented Microstructure
4
E 384 Test Method for Microhardness of Mat
...

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5.1 This practice is used to assess the nature and extent of banding or orientation of microstructures of metals and other materials where deformation and processing produce a banded or oriented condition.  
5.2 Banded or oriented microstructures can arise in single phase, two phase or multiphase metals and materials. The appearance of the orientation or banding is influenced by processing factors such as the solidification rate, the extent of segregation, the degree of hot or cold working, the nature of the deformation process used, the heat treatments, and so forth.  
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1.1 This practice describes a procedure to qualitatively describe the nature of banded or oriented microstructures based on the morphological appearance of the microstructure.  
1.2 This practice describes stereological procedures for quantitative measurement of the degree of microstructural banding or orientation.  
Note 1: Although stereological measurement methods are used to assess the degree of banding or alignment, the measurements are only made on planes parallel to the deformation direction (that is, a longitudinal plane) and the three-dimensional characteristics of the banding or alignment are not evaluated.  
1.3 This practice describes a microindentation hardness test procedure for assessing the magnitude of the hardness differences present in banded heat-treated steels. For fully martensitic carbon and alloy steels (0.10–0.65 %C), in the as-quenched condition, the carbon content of the matrix and segregate may be estimated from the microindentation hardness values.  
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1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
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1.3 Limitations of Test:  
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