ASTM A800/A800M-10
(Practice)Standard Practice for Steel Casting, Austenitic Alloy, Estimating Ferrite Content Thereof
Standard Practice for Steel Casting, Austenitic Alloy, Estimating Ferrite Content Thereof
SIGNIFICANCE AND USE
The tensile and impact properties, the weldability, and the corrosion resistance of iron-chromium-nickel alloy castings may be influenced beneficially or detrimentally by the ratio of the amount of ferrite to the amount of austenite in the microstructure. The ferrite content may be limited by purchase order requirements or by the design construction codes governing the equipment in which the castings will be used. The quantity of ferrite in the structure is fundamentally a function of the chemical composition of the alloy and its thermal history. Because of segregation, the chemical composition, and, therefore, the ferrite content, may differ from point to point on a casting. Determination of the ferrite content by any of the procedures described in the following practice is subject to varying degrees of imprecision which must be recognized in setting realistic limits on the range of ferrite content specified. Sources of error include the following:
In Determinations from Chemical Composition—Deviations from the actual quantity of each element present in an alloy because of chemical analysis variance, although possibly minor in each case, can result in substantial difference in the ratio of total ferrite-promoting to total austenite-promoting elements. Therefore, the precision of the ferrite content estimated from chemical composition depends on the accuracy of the chemical analysis procedure.
In Determinations from Magnetic Response—Phases other than ferrite and austenite may be formed at certain temperatures and persist at room temperature. These may so alter the magnetic response of the alloy that the indicated ferrite content is quite different from that of the same chemical composition that has undergone different thermal treatment. Also, because the magnets or probes of the various measuring instruments are small, different degrees of surface roughness or surface curvature will vary the magnetic linkage with the material being measured.
In Determinati...
SCOPE
1.1 This practice covers procedures and definitions for estimating ferrite content in certain grades of austenitic iron-chromium-nickel alloy castings that have compositions balanced to create the formation of ferrite as a second phase in amounts controlled to be within specified limits. Methods are described for estimating ferrite content by chemical, magnetic, and metallographic means.
1.2 The grades covered by this practice are: CF-3, CF-3A, CF-8, CF-8A, CF-3M, CF-3MA, CF-8M, CF-8C, CG-8M, and CH-10.
1.3 The values stated in either inch-pound units or SI units are to be regarded separately as standard. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the practice.
1.3.1 Within the text, the SI units are shown in brackets.
1.4 This standard does not purport to address the safety concerns, 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
Relations
Buy Standard
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: A800/A800M − 10
StandardPractice for
Steel Casting, Austenitic Alloy, Estimating Ferrite Content
1
Thereof
This standard is issued under the fixed designationA800/A800M; 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* A941 TerminologyRelatingtoSteel,StainlessSteel,Related
Alloys, and Ferroalloys
1.1 This practice covers procedures and definitions for
E38 Methods for Chemical Analysis of Nickel-Chromium
estimating ferrite content in certain grades of austenitic iron-
3
and Nickel-Chromium-Iron Alloys (Withdrawn 1989)
chromium-nickel alloy castings that have compositions bal-
E353 Test Methods for Chemical Analysis of Stainless,
anced to create the formation of ferrite as a second phase in
Heat-Resisting, Maraging, and Other Similar Chromium-
amounts controlled to be within specified limits. Methods are
Nickel-Iron Alloys
described for estimating ferrite content by chemical, magnetic,
E562 Test Method for Determining Volume Fraction by
and metallographic means.
Systematic Manual Point Count
1.2 The grades covered by this practice are: CF-3, CF-3A,
2.2 Constitution Diagrams:
CF-8, CF-8A, CF-3M, CF-3MA, CF-8M, CF-8C, CG-8M, and
Schoefer Diagram for Estimating Ferrite Content of Stain-
4
CH-10.
less Steel Castings (1980 revision)
1.3 The values stated in either inch-pound units or SI units Schaeffler Diagram for Estimating Ferrite Content of Stain-
5
less Steel Weld Metal
are to be regarded separately as standard. The values stated in
each system are not exact equivalents; therefore, each system DeLong Diagram for Estimating Ferrite Content of Stainless
6
Steel Weld Metal
must be used independently of the other. Combining values
from the two systems may result in nonconformance with the 2.3 American Welding Society Specification:
AWS A 4.2, Procedures for Calibrating Magnetic Instru-
practice.
1.3.1 Within the text, the SI units are shown in brackets. ments to Measure the Delta Ferrite Content of Austenitic
7
Stainless Steel Weld Metal
1.4 This standard does not purport to address the safety
concerns, if any, associated with its use. It is the responsibility
3. Terminology
of the user of this standard to establish appropriate safety and
3.1 Definitions:
health practices and determine the applicability of regulatory
3.1.1 ferrite—the ferromagnetic, body-centered, cubic-
limitations prior to use.
microstructuralconstituentofvariablechemicalcompositionin
iron-chromium-nickel alloys. This may be formed upon solidi-
2. Referenced Documents
fication from the molten metal (delta ferrite) or by transforma-
2
2.1 ASTM Standards:
tion from austenite or sigma phase on cooling in the solid state
A351/A351M Specification for Castings, Austenitic, for
(alpha ferrite).
Pressure-Containing Parts
3.1.2 ferrite content—the proportion of total volume of an
A370 Test Methods and Definitions for Mechanical Testing
iron-chromium-nickel alloy present as the ferrite phase.
of Steel Products
A799/A799M Practice for Steel Castings, Stainless, Instru-
3.1.3 ferrite number—the ferrite content expressed as an
ment Calibration, for Estimating Ferrite Content
arbitrary number based on the magnetic response of the alloy
in a weld deposit.
1
This practice is under the jurisdiction of ASTM Committee A01 on Steel,
3
Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee The last approved version of this historical standard is referenced on
A01.18 on Castings. www.astm.org.
4
Current edition approved Oct. 1, 2010. Published November 2010. Originally Appendix of this practice.
5
approved in 1982. Last previous edition approved in 2006 as A800/A800M – 01 Metal Progress Data Book, American Society for Metals, Mid June 1977, p.
(2006). DOI: 10.1520/A0800_A0800M-10. 161.
2 6
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Welding Journal, American Welding Society, Vol 38, No. 7, July 1973, p.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM 293–s.
7
Standards volume information, refer to the standard’s Document Summary page on Available from American Welding Society (AWS), 550 NW LeJeune Rd.,
the ASTM website. Miami, FL 33126.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1
---------------------- Page: 1 ----------------------
A800/A800M − 10
3.1.4 ferrite percentage—the ferrite content expressed as a 5.1.3 Required ferrite content range, in volume percent, of
volume percent. the castings after final heat treatmen
...
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:A800/A800M–01 (Reapproved 2006) Designation: A800/A800M – 10
Standard Practice for
Steel Casting, Austenitic Alloy, Estimating Ferrite Content
1
Thereof
This standard is issued under the fixed designationA800/A800M; 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 practice covers procedures and definitions for estimating ferrite content in certain grades of austenitic iron-chromium-
nickel alloy castings that have compositions balanced to create the formation of ferrite as a second phase in amounts controlled
to be within specified limits. Methods are described for estimating ferrite content by chemical, magnetic, and metallographic
means.
1.2 The grades covered by this practice are: CF-3, CF-3A, CF-8, CF-8A, CF-3M, CF-3MA, CF-8M, CF-8C, CG-8M, and
CH-10.
1.3 Thevaluesstatedineitherinch-poundunitsorSIunitsaretoberegardedseparatelyasstandard.Withinthetext,theSIunits
are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system must be used
independently of the other. Combining values from the two systems may result in nonconformance with the practice.
1.3.1 Within the text, the SI units are shown in brackets.
1.4 This standard does not purport to address the safety concerns, 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.
2. Referenced Documents
2
2.1 ASTM Standards:
A351/A351M Specification for Castings, Austenitic, for Pressure-Containing Parts
A370 Test Methods and Definitions for Mechanical Testing of Steel Products
A799/A799M Practice for Steel Castings, Stainless, Instrument Calibration, for Estimating Ferrite Content
A941 Terminology Relating to Steel, Stainless Steel, Related Alloys, and Ferroalloys
E38 Methods for Chemical Analysis of Nickel-Chromium and Nickel-Chromium-Iron Alloys
E353 Test Methods for Chemical Analysis of Stainless, Heat-Resisting, Maraging, and Other Similar Chromium-Nickel-Iron
Alloys
E562 Test Method for Determining Volume Fraction by Systematic Manual Point Count
2.2 Constitution Diagrams:
3
Schoefer Diagram for Estimating Ferrite Content of Stainless Steel Castings (1980 revision)
4
Schaeffler Diagram for Estimating Ferrite Content of Stainless Steel Weld Metal
5
DeLong Diagram for Estimating Ferrite Content of Stainless Steel Weld Metal
2.3 American Welding Society Specification:
AWSA4.2, Procedures for Calibrating Magnetic Instruments to Measure the Delta Ferrite Content ofAustenitic Stainless Steel
6
Weld Metal
1
This practice is under the jurisdiction of ASTM Committee A01 on Steel, Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee A01.18
on Castings.
Current edition approved March 1, 2006. Published April 2006. Originally approved in 1982. Last previous edition approved in 2001 as A800/A800M–01. DOI:
10.1520/A0800_A0800M-01R06.
CurrenteditionapprovedOct.1,2010.PublishedNovember2010.Originallyapprovedin1982.Lastpreviouseditionapprovedin2006asA800/A800M – 01(2006).DOI:
10.1520/A0800_A0800M-10.
2
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
Appendix of this practice.
4
Metal Progress Data Book, American Society for Metals, Mid June 1977, p. 161.
5
Welding Journal, American Welding Society, Vol 38, No. 7, July 1973, p. 293–s.
6
Available from American Welding Society (AWS), 550 NW LeJeune Rd., Miami, FL 33126.
*A Summary of Changes section appears at the end of this standard.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1
---------------------- Page: 1 ----------------------
A800/A800M – 10
3. Terminology
3.1 Definitions:
3.1.1 ferrite—the ferromagnetic, body-centered, cubic-microstructural constituent of variable chemical composition in
iron-chromium-nickel alloys. This may be formed upon solidification from the molten metal (delta ferrite) or by transformation
from austenite or sigma phase on cooling in the solid state (alpha ferrite).
3.1.2 ferrite content—the
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.