oSIST prEN ISO 7799:2026

• Abstract:

  Specifies the method for determining the ability of sheet and strip to undergo plastic deformation in reverse bending. Can be applied to aluminium and its alloys only after previous agreement. The reverse bend test consists of repeated bending through 90 , in opposite directions, of a rectangular test piece held at one end, each bend being over a cylindrical support of specified radius.

• Status: Not Published
• Public Enquiry End Date: 16-Jul-2026
• ICS: 77.040.10 - Mechanical testing of metals
• Technical Committee: PKG - Testing of metallic materials
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 06-May-2026
• Due Date: 23-Sep-2026
• Completion Date: 28-Jul-2026
• Ref Project: prEN ISO 7799 - Metallic materials - Sheet and strip 3 mm thick or less - Reverse bend test (ISO/DIS 7799:2026)

• Revises: SIST EN ISO 7799:2000 - Metallic materials - Sheet and strip 3 mm thick or less - Reverse bend test (ISO 7799:1985)
• Effective Date: 17-Jul-2024

Overview

oSIST prEN ISO 7799:2026 establishes a standardized method for evaluating the plastic deformation ability of metallic sheet and strip materials, 3 mm thick or less, through the reverse bend test. This international standard is relevant to a wide range of metals, with the application to aluminium and its alloys subject to prior agreement. The reverse bend test involves repeatedly bending a rectangular test specimen through 90° in alternating directions over a cylindrical support of specified radius, simulating repeated deformation and assessing resistance to cracking or failure.

Compliance with this standard ensures consistent quality evaluation and comparability in the mechanical testing of metals across industries worldwide.

Key Topics

• Scope and Applicability
  • Applies to metallic sheet and strip materials with thickness ≤ 3 mm.
  • Use for aluminium and its alloys only after specific agreement.
• Reverse Bend Test Method
  • Involves repeated 90° bends in opposite directions over a cylindrical support.
  • Test continues until a specified number of bends is completed or the specimen fractures.
• Equipment and Test Pieces
  • Test requires specific test apparatus featuring cylindrical supports, a bending arm, and gripping faces.
  • Test specimens should be prepared with strict dimensional and surface quality requirements to minimize external influences.
• Test Conditions and Parameters
  • Standardized dimensions, radii, and testing rates to ensure reproducibility.
  • Test temperature typically ranges from 10 to 35°C, with controlled conditions at 23 ± 5°C if required.
• Reporting Requirements
  • Results must include reference to the standard, specimen identification, dimensions, test conditions, and any deviations from standard procedures.
  • Final report records total number of successful reverse bends and observations on specimen failure.

Applications

The reverse bend test outlined in oSIST prEN ISO 7799:2026 is critical within the mechanical testing of metals and is applied in several practical areas:

• Quality Control: Used by manufacturers and suppliers to verify the ductility and flexibility of metal sheet and strip products, ensuring materials can withstand repeated flexing in service.
• Material Comparison: Enables direct comparison of ductile properties between different metal alloys, processing methods, or heat treatments.
• Process Validation: Supports metal forming, stamping, and fabrication industries in validating that processed materials meet ductility and bend-resistance requirements.
• Regulatory Compliance: Assists organizations in meeting contractual or regulatory requirements for metal performance, especially in industries like automotive, HVAC, electronics, and construction.
• R&D and Product Development: Aids research teams in developing new metal products or improving existing ones by offering reliable mechanical performance data.

Related Standards

For comprehensive quality assurance and in-depth testing regimes, oSIST prEN ISO 7799:2026 should be used in conjunction with related standards:

• ISO 24259:2022 - Steel strapping for packaging
• ASTM A720/A720M-02:2021 - Standard Test Method for Ductility of Nonoriented Electrical Steel
• IEC/TR 63114:2018 - Reverse Bend Test Method of Electrical Steel Strip and Sheet

These standards, along with oSIST prEN ISO 7799:2026, help technical professionals and quality managers maintain robust testing and certification processes within the field of mechanical testing of metals.

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By adhering to oSIST prEN ISO 7799:2026, organizations ensure reliability and consistency in evaluating the ductility of metallic sheet and strip materials, supporting quality-driven manufacturing and international trade.

SLOVENSKI STANDARD
01-julij-2026
Kovinski materiali - Plošče in trakovi debeline 3 mm ali manj - Preskus upogibanja
v nasprotni smeri (ISO/DIS 7799:2026)
Metallic materials - Sheet and strip 3 mm thick or less - Reverse bend test (ISO/DIS
7799:2026)
Metallische Werkstoffe - Bleche und Bänder mit einer Dicke unter 3 mm - Hin- und
Herbiegeversuch (ISO/DIS 7799:2026)
Matériaux métalliques - Tôles et feuillards d'épaisseur inférieure ou égale à 3 mm - Essai
de pliage alterné (ISO/DIS 7799:2026)
Ta slovenski standard je istoveten z: prEN ISO 7799
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.

DRAFT
International
Standard
ISO/DIS 7799
ISO/TC 164/SC 2
Metallic materials — Sheet and strip
Secretariat: JISC
3 mm thick or less — Reverse bend
Voting begins on:
test
2026-04-28
Matériaux métalliques — Tôles et feuillards d'épaisseur
Voting terminates on:
inférieure ou égale à 3 mm — Essai de pliage alterné
2026-07-21
ICS: 77.040.10
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS.
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Reference number
ISO/DIS 7799:2026(en)
DRAFT
ISO/DIS 7799:2026(en)
International
Standard
ISO/DIS 7799
ISO/TC 164/SC 2
Metallic materials — Sheet and strip
Secretariat: JISC
3 mm thick or less — Reverse bend
Voting begins on:
test
Matériaux métalliques — Tôles et feuillards d'épaisseur
Voting terminates on:
inférieure ou égale à 3 mm — Essai de pliage alterné
ICS: 77.040.10
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2026
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
BE CONSIDERED IN THE LIGHT OF THEIR
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
or ISO’s member body in the country of the requester.
NATIONAL REGULATIONS.
ISO copyright office
RECIPIENTS OF THIS DRAFT ARE INVITED
CP 401 • Ch. de Blandonnet 8
TO SUBMIT, WITH THEIR COMMENTS,
CH-1214 Vernier, Geneva
NOTIFICATION OF ANY RELEVANT PATENT
Phone: [phone]
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Email: [e-mail]
Website: www.iso.org
Published in Switzerland Reference number
ISO/DIS 7799:2026(en)
ii
ISO/DIS 7799:2026(en)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and designations . 1
5 Principle . 1
6 Testing equipment . 2
6.1 General .2
6.2 Cylindrical supports and gripping faces .3
6.3 Bending arm and guide .3
7 Test piece . 3
8 Procedure . 4
9 Test report . 5
Annex A (informative) Examples of some devices applying force to test pieces . 6
Bibliography . 8

iii
ISO/DIS 7799:2026(en)
Foreword
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This document was prepared by Technical Committee ISO/TC 164, Mechanical testing of metals, Subcommittee
SC 2, Ductility testing.
This second edition cancels and replaces the first edition (ISO 7799:1985), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— symbols for applied tension, F, width of test piece, b and width of slit of the guide, w have been added in
Table 1;
— Table 2 has been adjusted to include the limits of the distance, L, from the top tangential plane of
cylindrical supports to the bottom face of the guide, and the width of the slit of the guide, w;
— the test piece length has been modified for ease of application;
— the requirements for t
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