ASTM B933-16

Standard Test Method for Microindentation Hardness of Powder Metallurgy (PM) Materials

SIGNIFICANCE AND USE
5.1 Microindentation hardness testing provides a measure of the hardness of the microstructural constituents of a porous material. It indicates the hardness the material would have if there were no pores present and the material was tested using macroindentation hardness methods. Loads are limited to a maximum of 200 gf to reduce the likelihood of interference from the porosity.  
5.2 Microindentation hardness tests allow the evaluation of specific phases, microstructural constituents, and regions or gradients too small for macroindentation hardness testing.
SCOPE
1.1 This test method covers the determination of the microindentation hardness of powder metallurgy (PM) materials. The test method differs from the approach used for pore-free materials in terms of the precautions required to deal with the porosity.  
1.2 This procedure covers tests made with the Knoop or Vickers indenters under loads in the range from 1 to 200 gf.  
1.3 Automated testing is not generally suitable for use with porous PM materials, because acceptable indentations require avoiding placing indentations in the immediate vicinity of a pore, a condition not guaranteed with automated placement of the indentations. Any automated testing shall allow for review of indentations post-test to reject any distorted or unusually large indentations in accordance with 9.4.  
1.4 A method for converting the directly measured indentation lengths to other hardness scales, for example, HRC is described in Appendix X1.  
1.5 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 and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-Mar-2016
• ICS: 77.160 - Powder metallurgy
• Technical Committee: B09 - Metal Powders and Metal Powder Products
• Drafting Committee: B09.05 - Structural Parts

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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: B933 − 16
Standard Test Method for
Microindentation Hardness of Powder Metallurgy (PM)
1
Materials
This standard is issued under the fixed designation B933; 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* 3. Terminology
1.1 This test method covers the determination of the micro-
3.1 Definitions of powder metallurgy (PM) terms can be
indentation hardness of powder metallurgy (PM) materials. found in Terminology B243. Additional descriptive informa-
The test method differs from the approach used for pore-free
tion is available in the Related Materials section of Vol 02.05
materials in terms of the precautions required to deal with the of the Annual Book of ASTM Standards.
porosity.
4. Summary of Test Method
1.2 This procedure covers tests made with the Knoop or
Vickers indenters under loads in the range from 1 to 200 gf.
4.1 Microindentation hardness testing uses a calibrated
machine to force a pyramidal-pointed diamond indenter into
1.3 Automated testing is not generally suitable for use with
the surface of the test material under a known test load. The
porous PM materials, because acceptable indentations require
microindentation hardness value is calculated from the indent-
avoiding placing indentations in the immediate vicinity of a
ing force divided by the projected area of the resulting
pore, a condition not guaranteed with automated placement of
indentation.
the indentations.Any automated testing shall allow for review
NOTE 1—This test method is designed specifically for use on porous
of indentations post-test to reject any distorted or unusually
PM materials. It is intended to be a companion to Test Method E384.
large indentations in accordance with 9.4.
There are specific differences that are intentional such as restricting the
appliedloadtoamaximumof200gf;otherwise,thedetailsonequipment
1.4 Amethod for converting the directly measured indenta-
and procedures in Test Method E384 shall be adhered to. The specific
tion lengths to other hardness scales, for example, HRC is
differences relate to the presence of porosity in the PM materials. Special
described in Appendix X1.
precautions are required during sample preparation to reveal pores and
heterogeneous microstructural features so that appropriate test locations
1.5 This standard does not purport to address all of the
may be selected.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
5. Significance and Use
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
5.1 Microindentationhardnesstestingprovidesameasureof
the hardness of the microstructural constituents of a porous
2. Referenced Documents
material. It indicates the hardness the material would have if
2
there were no pores present and the material was tested using
2.1 ASTM Standards:
macroindentation hardness methods. Loads are limited to a
B243Terminology of Powder Metallurgy
maximum of 200 gf to reduce the likelihood of interference
E384Test Method for Microindentation Hardness of Mate-
from the porosity.
rials
E691Practice for Conducting an Interlaboratory Study to
5.2 Microindentation hardness tests allow the evaluation of
Determine the Precision of a Test Method
specific phases, microstructural constituents, and regions or
gradients too small for macroindentation hardness testing.
1
This test method is under the jurisdiction of ASTM Committee B09 on Metal
6. Apparatus
Powders and Metal Powder Products and is the direct responsibility of Subcom-
mittee B09.05 on Structural Parts.
6.1 Microindentation Hardness Testing Machine,capableof
Current edition approved April 1, 2016. Published April 2016. Originally
applying the required load, equipped with a Knoop or Vickers
approved in 2004. Last previous edition approved in 2014 as B933 – 14. DOI:
indenter, and provision for measuring the length of the diago-
10.1520/B0933-16.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or nals of the indentation.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
6.2 Apparatus requirements are summarized in methodTest
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. Method E384.
*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

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B933 − 16
7. Reagents and Materials
Indentation Len
...

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: B933 − 14 B933 − 16
Standard Test Method for
Microindentation Hardness of Powder Metallurgy (PM)
1
Materials
This standard is issued under the fixed designation B933; 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 test method covers the determination of the microindentation hardness of powder metallurgy (PM) materials. The test
method differs from the approach used for pore-free materials in terms of the precautions required to deal with the porosity.
1.2 This procedure covers tests made with the Knoop or Vickers indenters under loads in the range from 1 to 200 gf.
1.3 Automated testing is not generally suitable for use with porous PM materials, because acceptable indentations require
avoiding placing indentations in the immediate vicinity of a pore, a condition not guaranteed with automated placement of the
indentations. Any automated testing shall allow for review of indentations post-test to reject any distorted or unusually large
indentations in accordance with 9.4.
1.4 A method for converting the directly measured indentation lengths to other hardness scales, for example, HRC is described
in Appendix X1.
1.5 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 and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
B243 Terminology of Powder Metallurgy
E384 Test Method for Microindentation Hardness of Materials
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
3. Terminology
3.1 Definitions of powder metallurgy (PM) terms can be found in Terminology B243. Additional descriptive information is
available in the Related Materials section of Vol 02.05 of the Annual Book of ASTM Standards.
4. Summary of Test Method
4.1 Microindentation hardness testing uses a calibrated machine to force a pyramidal-pointed diamond indenter into the surface
of the test material under a known test load. The microindentation hardness value is calculated from the indenting force divided
by the projected area of the resulting indentation.
NOTE 1—This test method is designed specifically for use on porous PM materials. It is intended to be a companion to Test Method E384. There are
specific differences that are intentional; intentional such as restricting the applied load to a maximum of 200 gf; otherwise, the details on equipment and
procedures in Test Method E384 shall be adhered to. The specific differences relate to the presence of porosity in the PM materials. Special precautions
are required during sample preparation to reveal pores and heterogeneous microstructural features so that appropriate test locations may be selected.
5. Significance and Use
5.1 Microindentation hardness testing provides a measure of the hardness of the microstructural constituents of a porous
material. It indicates the hardness the material would have if there were no pores present and the material was tested using
macroindentation hardness methods. Loads are limited to a maximum of 200 gf to reduce the likelihood of interference from the
porosity.
1
This test method is under the jurisdiction of ASTM Committee B09 on Metal Powders and Metal Powder Products and is the direct responsibility of Subcommittee B09.05
on Structural Parts.
Current edition approved April 1, 2014April 1, 2016. Published April 2014April 2016. Originally approved in 2004. Last previous edition approved in 20092014 as
B933–09. DOI: 10.1520/B0933-14. – 14. DOI: 10.1520/B0933-16.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’sstandard’s Document Summary page on the ASTM website.
*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 ----------------------
B933 − 16
5.2 Microindentation hardness tests allow the evaluation of specific phases, microstructural constituents, and regions or
gradients t
...