SIST EN ISO 14577-3:2026
(Main)Metallic materials - Instrumented indentation test for hardness and materials parameters - Part 3: Calibration of reference blocks (ISO 14577-3:2026)
- Abstract
This document specifies a method for the calibration of reference blocks to use for the indirect verification of testing machines for the instrumented indentation test as specified in ISO 14577-2.
Reference materials, where it is necessary to prepare a surface before the test in a manner that removes surface layers are excluded from this standard.
- Status
- Published
- Public Enquiry End Date
- 29-Sep-2024
- Publication Date
- 29-Sep-2026
- Technical Committee
- PKG - Testing of metallic materials
- Current Stage
- 6060 - National Implementation/Publication (Adopted Project)
- Start Date
- 08-Jun-2026
- Due Date
- 13-Aug-2026
- Completion Date
- 30-Sep-2026
SIST EN ISO 14577-3:2026 is the Slovenian adoption, published by SIST, of the standard for calibrating reference blocks used in instrumented indentation testing of metallic materials. It specifies how to prepare, calibrate, mark, and validate those blocks so they can be used for indirect verification of testing machines in ISO 14577-2. The standard is intended for calibration laboratories, reference-material producers, and users who need certified blocks for hardness and materials-parameter measurements.
What does SIST EN ISO 14577-3:2026 specify?
SIST EN ISO 14577-3:2026 specifies the calibration method for reference blocks used to verify instrumented indentation testing machines indirectly. It also sets the requirements for the blocks, the calibrating machine, the calibration procedure, and the information that must accompany a calibrated block.
The scope is limited to reference blocks for ISO 14577-2. Reference materials that need surface preparation removing surface layers are outside the document’s scope.
The document is organized into clauses on scope, normative references, manufacturing, the calibrating machine, calibration procedure, number of indentations, uniformity, marking, and validity.
| Annex | What it covers |
|---|---|
| Annex A | An informative example procedure for measuring elasticity of reference materials with the pulse echo method and traceability |
What are the key requirements of SIST EN ISO 14577-3:2026?
Reference block manufacture
SIST EN ISO 14577-3:2026 requires the reference block to be specially prepared so the material has the homogeneity, uniformity, and stability needed for calibration. The block must also be thick enough for the intended indentation range, free from magnetism, and shaped so it can be mounted correctly in the testing machine.
In practice, this means the block producer has to control material structure, mounting geometry, and surface condition from the start. The test surface must be the only test surface, and it must not carry scratches that interfere with indentation measurement.
The document also requires the surface roughness to be low enough for the intended minimum indentation depth, with roughness assessment aligned to ISO 21920 (all parts). For bottom-mounted samples, the underside must be flat and aligned so mounting does not add compliance or tilt errors.
Calibrating machine and measurement chain
SIST EN ISO 14577-3:2026 requires the calibrating machine to meet the conditions in ISO 14577-2 and to be directly calibrated and verified at intervals not exceeding 24 months. The calibration chain must cover test force, indenter verification, displacement measurement, and the test cycle.
This matters because a calibrated block is only as good as the machine used to create it. The instruments used for verification and calibration must be traceable to the SI, so the certified values can be trusted and compared across laboratories.
The force system must meet tight uncertainty limits for macro, micro, and nano use, and the force-proving instrument must be suitable for the range. The indenter must be verified by direct measurement, with shape-specific checks for Vickers, Berkovich, modified Berkovich, corner cube, ball, and spheroconical indenters.
Indenter verification and depth measurement
SIST EN ISO 14577-3:2026 places strong emphasis on the certified measured values of the indenter and, for shallow indentations, on the certified area function. The document expects direct imaging and 3D shape measurement for verification, and it points to methods such as atomic force microscopy when appropriate.
For users, this means the indenter cannot be treated as a generic tip. Its geometry affects the certified block values, especially in the micro and nano ranges, where tip shape and area function are critical to depth and modulus results.
The displacement measuring device must also be capable of estimating indentation depth with range-dependent uncertainty limits. The document separates macro, micro, and nano ranges because the required precision becomes more demanding as indentations become smaller.
Testing cycle and calibration procedure
SIST EN ISO 14577-3:2026 requires calibration to be carried out with the general indentation procedure from ISO 14577-1 and at the temperature stated in the calibration certificate. The test cycle must satisfy the timing and data-acquisition conditions in the document, including requirements for loading, holding, unloading, and the number of recorded points.
In practice, this means calibration is not just a force-and-depth reading. The whole cycle has to be controlled so that creep, unloading behavior, vibration, and approach speed do not distort the certified values.
Number of indentations and uniformity
SIST EN ISO 14577-3:2026 requires multiple force levels across the range of use, with replicated indentations distributed across the block surface. The surface locations should be spread out so the calibration captures inhomogeneity rather than averaging it away.
Uniformity is assessed from grouped mean values and their deviation from the reference value. The practical result is a block that can be used with confidence only if its response is sufficiently even across the surface and across the intended indentation sizes.
Marking and validity
SIST EN ISO 14577-3:2026 requires each block to be marked directly or linked to a certificate by unique identification. The identification has to support traceability to the calibrated values, the supplier or manufacturer, the calibrating agency, the block thickness or surface mark, the calibration year, and the test-surface location.
The block is valid only for the testing conditions used during calibration and only while it still meets the block requirements. The document also recommends limiting the calibration validity period to five years.
What terms does SIST EN ISO 14577-3:2026 define?
SIST EN ISO 14577-3:2026 does not list formal terms in a definitions clause, but it uses several key terms consistently:
- Reference block - a specially prepared block whose certified indentation values are used to calibrate or check testing machines.
- Indirect verification - verification of a testing machine by comparing results against a calibrated reference block rather than by direct primary measurement alone.
- Calibrating machine - the machine used to calibrate the reference block; it must itself meet the document’s calibration and verification requirements.
- Indenter - the tip or probe shape that makes the indentation, such as Vickers, Berkovich, ball, or spheroconical.
- Displacement measuring device - the part of the machine that measures indentation depth during the test cycle.
- HM - Martens hardness, used here as one of the certified indentation parameters.
- E_IT - indentation modulus, the elastic parameter derived from instrumented indentation data.
- CRM - certified reference material, the material whose certified value is used as the calibration target.
Who uses SIST EN ISO 14577-3:2026?
SIST EN ISO 14577-3:2026 is used by calibration laboratories, reference-material manufacturers, testing laboratories, and quality departments that work with instrumented indentation hardness testing. It is also relevant to machine manufacturers and service providers who verify or calibrate indentation testing systems.
In practice, these users apply the standard when they prepare certified blocks, set up calibration equipment, issue calibration certificates, check machine compliance, or buy blocks for routine verification. It is especially relevant in metals testing, steel testing, and other mechanical testing work covered by ISO 14577.
What changed in SIST EN ISO 14577-3:2026 from the previous edition?
SIST EN ISO 14577-3:2026 supersedes EN ISO 14577-3:2015. The document states these main changes:
- specification of the shape of the reference block
- modifications in the procedure for verification of the indenter
- testing cycle requirements
- changed conditions for verifying the uniformity of the reference blocks
- Annex A added
Which standards are used with SIST EN ISO 14577-3:2026?
SIST EN ISO 14577-3:2026 is used together with these standards named in the document:
- ISO 376 - provides the calibration basis for force-proving instruments used to verify the test force.
- ISO 14577-1 - gives the general test method for instrumented indentation and is used for the indentation procedure, cycle requirements, and related test conditions.
- ISO 14577-2 - defines verification and calibration of testing machines, and this part builds on it for indirect verification using reference blocks.
- ISO 21920 (all parts) - supports the surface texture profile measurements used when checking surface roughness.
What does the SIST EN ISO 14577-3:2026 document contain?
The document contains tables for block thickness, displacement-measurement capability, uncertainty limits, and reference-block uniformity, so the reader can see which calibration conditions apply to each indentation range. It also includes a figure for the square Vickers-section geometry and formulas for averaging replicated results and assessing relative deviation.
Clause 8 uses statistical treatment of grouped indentations to assess block uniformity, and Annex A provides an example pulse echo method for measuring elasticity of reference materials with traceability. That annex includes a practical setup, measurement sequence, and analysis path for density, thickness, wave velocity, Young’s modulus, and Poisson’s ratio.
Relations
- Effective Date
- 01-Oct-2026
- Effective Date
- 03-Jun-2026
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Frequently Asked Questions
SIST EN ISO 14577-3:2026 is a standard published by the Slovenian Institute for Standardization (SIST). Its full title is "Metallic materials - Instrumented indentation test for hardness and materials parameters - Part 3: Calibration of reference blocks (ISO 14577-3:2026)". This standard covers: This document specifies a method for the calibration of reference blocks to use for the indirect verification of testing machines for the instrumented indentation test as specified in ISO 14577-2. Reference materials, where it is necessary to prepare a surface before the test in a manner that removes surface layers are excluded from this standard.
This document specifies a method for the calibration of reference blocks to use for the indirect verification of testing machines for the instrumented indentation test as specified in ISO 14577-2. Reference materials, where it is necessary to prepare a surface before the test in a manner that removes surface layers are excluded from this standard.
SIST EN ISO 14577-3:2026 is classified under the following ICS (International Classification for Standards) categories: 77.040.10 - Mechanical testing of metals. The ICS classification helps identify the subject area and facilitates finding related standards.
SIST EN ISO 14577-3:2026 has the following relationships with other standards: It is inter standard links to SIST EN ISO 14577-3:2015, SIST EN ISO 14577-4:2008. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
SIST EN ISO 14577-3:2026 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
SLOVENSKI STANDARD
01-november-2026
Kovinski materiali - Instrumentirano vtiskanje pri preskušanju trdote in drugih
lastnosti materialov - 3. del: Kalibracija referenčnih etalonov (ISO 14577-3:2026)
Metallic materials - Instrumented indentation test for hardness and materials parameters
- Part 3: Calibration of reference blocks (ISO 14577-3:2026)
Metallische Werkstoffe- Instrumentierte Eindringprüfung zur Bestimmung der Härte und
anderer Werkstoffparameter- Teil3: Kalibrierung von Referenzproben(ISO 14577-3:2026)
Matériaux métalliques - Essai de pénétration instrumenté pour la détermination de la
dureté et de paramètres des matériaux - Partie 3: Étalonnage des blocs de référence
(ISO 14577-3:2026)
Ta slovenski standard je istoveten z: EN ISO 14577-3:2026
ICS:
77.040.10 Mehansko preskušanje kovin Mechanical testing of metals
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EN ISO 14577-3
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2026
EUROPÄISCHE NORM
ICS 77.040.10 Supersedes EN ISO 14577-3:2015
English Version
Metallic materials - Instrumented indentation test for
hardness and materials parameters - Part 3: Calibration of
reference blocks (ISO 14577-3:2026)
Matériaux métalliques - Essai de pénétration Metallische Werkstoffe- Instrumentierte
instrumenté pour la détermination de la dureté et de Eindringprüfung zur Bestimmung der Härte und
paramètres des matériaux - Partie 3: Étalonnage des anderer Werkstoffparameter- Teil3: Kalibrierung von
blocs de référence (ISO 14577-3:2026) Referenzproben(ISO 14577-3:2026)
This European Standard was approved by CEN on 27 April 2026.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 14577-3:2026 E
worldwide for CEN national Members.
Contents Page
European foreword . 3
European foreword
This document (EN ISO 14577-3:2026) has been prepared by Technical Committee ISO/TC 164
"Mechanical testing of metals" in collaboration with Technical Committee CEN/TC 459/SC 1 “Test
methods for steel (other than chemical analysis)” the secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by November 2026, and conflicting national standards
shall be withdrawn at the latest by November 2026.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 14577-3:2015.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 14577-3:2026 has been approved by CEN as EN ISO 14577-3:2026 without any
modification.
International
Standard
ISO 14577-3
Third edition
Metallic materials — Instrumented
2026-05
indentation test for hardness and
materials parameters —
Part 3:
Calibration of reference blocks
Matériaux métalliques — Essai de pénétration instrumenté pour
la détermination de la dureté et de paramètres des matériaux —
Partie 3: Étalonnage des blocs de référence
Reference number
ISO 14577-3:2026(en) © ISO 2026
ISO 14577-3:2026(en)
© ISO 2026
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 14577-3:2026(en)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Manufacture of reference blocks . 1
5 Calibrating machine . 2
5.1 General .2
5.2 Calibration of the test force .3
5.3 Verification of the indenter .3
5.3.1 General .3
5.3.2 Vickers indenter .3
5.3.3 Berkovich, modified Berkovich and corner cube indenters .4
5.3.4 Ball indenters, and spheroconical indenters .4
5.4 Calibration of the displacement measuring device .4
5.5 Testing cycle requirements .5
6 Calibration procedure . 5
7 Number of indentations . 6
8 Uniformity of the reference blocks . 6
9 Marking . . 7
10 Validity . 8
Annex A (informative) Example procedure for measuring elasticity of reference materials with
pulse echo method with traceability. . 9
Bibliography .11
iii
ISO 14577-3:2026(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 164, Mechanical testing of metals, Subcommittee
SC 3, Hardness testing, in collaboration with the European Committee for Standardization (CEN) Technical
Committee CEN/TC 459/SC 1, Test methods for steel (other than chemical analysis, in accordance with the
Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
This third edition cancels and replaces the second edition (ISO 14577-3:2015), which has been technically
revised.
The main changes are as follows:
— Specification of the shape of the reference block.
— Modifications in the procedure for the verification of the indenter.
— Testing cycle requirements.
— Changing the conditions for the verification of the uniformity of the reference blocks.
— Annex A was added.
A list of all parts in the ISO 14577 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
ISO 14577-3:2026(en)
Introduction
Hardness has typically been defined as the resistance of a material to permanent penetration by another
harder material. The results obtained when performing Rockwell, Vickers, and Brinell tests are determined
after the test force has been removed. Therefore, the effect of elastic deformation under the indenter has
been ignored.
ISO 14577 (all parts) has been prepared to enable the user to evaluate the indentation of materials by
considering both the force and displacement during plastic and elastic deformation. By monitoring
the complete cycle of increasing and removal of the test force, hardness values equivalent to traditional
hardness values can be determined. More significantly, additional properties of the material such as its
indentation modulus and elasto-plastic hardness can also be determined. All these values can be calculated
without the requirement to measure the indent optically. Furthermore, by a variety of techniques, the
instrumented indentation test allows to record hardness and modulus depth profiles within a, probably
complex, indentation cycle.
ISO 14577 (all parts) has been written to allow a wide variety of post test data analysis.
v
International Standard ISO 14577-3:2026(en)
Metallic materials — Instrumented indentation test for
hardness and materials parameters —
Part 3:
Calibration of reference blocks
1 Scope
This document specifies a method for the calibration of reference blocks to use for the indirect verification
of testing machines for the instrumented indentation test as specified in ISO 14577-2.
Reference materials, where it is necessary to prepare a surface before the test in a manner that removes
surface layers are excluded from this standard.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 376, Metallic materials — Calibration of force-proving instruments used for the verification of uniaxial
testing machines
ISO 14577-1, Metallic materials — Instrumented indentation test for hardness and materials parameters —
Part 1: Test method
ISO 14577-2, Metallic materials — Instrumented indentation test for hardness and materials parameters —
Part 2: Verification and calibration of testing machines
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
4 Manufacture of reference blocks
4.1 The block shall be specially prepared and the attention of the manufacturer drawn to the requirement
to use a manufacturing process that gives the necessary homogeneity, uniformity, and stability of structure.
When the reference block is used for certifying hardness then it shall have a constant hardness over the
range of indentation sizes for which it is certified.
NOTE Variation in hardness with variation in indentation size occurs when the microstructural length scale of the
material is within an order of magnitude of the indentation size. Microstructural length scale is in this circumstance
the combined frequency of all length scales in the material, for example grain size, precipitate spacing, layer thickness
et cetera.
ISO 14577-3:2026(en)
4.2 Each block being calibrated shall be of a thickness greater or equal to that given in Table 1.
Table 1 — Thickness requirements for reference blocks
Range according to ISO 14577-1:2026, 1. Thickness
mm
Nano 2
Micro up to 500 mN 3
Micro up to 2 N 5
Macro up to 60 N 6
Macro up to 1 kN 12
Macro up to 30 kN 16
4.3 The reference blocks shall be free from magnetism. The manufacturers should ensure that the blocks
are demagnetized at the end of the manufacturing process.
4.4 The reference block shall be constructed such that it can be mounted in the testing machine.
For bottom mounted samples, the reference block shall have a flat bottom surface such that the sample to
stage interface contact does not contribute an additional frame compliance e.g. by deformation of asperities.
The sample bottom surface shall be perpendicular to the indentation direction when mounted and parallel
to the top surface so that the indentation tilt limits of ISO 14577-1 are met.
NOTE A 1° tilt is a slope of 0,175 mm per 10 mm sample length.
4.5 There shall be only one test surface on the block and the test surface shall be free from scratches that
interfere with the measurement of the indentations. Indentations between scratches are permitted.
The surface rou
...