EN ISO 18595:2021

SLOVENSKI STANDARD
01-maj-2021
Nadomešča:
SIST EN ISO 18595:2008
Uporovno varjenje - Točkovno varjenje aluminija in aluminijevih zlitin - Varivost,
varjenje in preskušanje (ISO 18595:2021)
Resistance welding - Spot welding of aluminium and aluminium alloys - Weldability,
welding and testing (ISO 18595:2021)
Widerstandsschweißen - Punktschweißen von Aluminium und Aluminiumlegierungen -
Schweißeignung, Schweißen und Prüfungen (ISO 18595:2021)
Soudage par résistance - Soudage par points de l'aluminium et des alliages d'aluminium
- Soudabilité, soudage et essais (ISO 18595:2021)
Ta slovenski standard je istoveten z: EN ISO 18595:2021
ICS:
25.160.10 Varilni postopki in varjenje Welding processes
77.120.10 Aluminij in aluminijeve zlitine Aluminium and aluminium
alloys
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 18595
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2021
EUROPÄISCHE NORM
ICS 25.160.10 Supersedes EN ISO 18595:2007
English Version
Resistance welding - Spot welding of aluminium and
aluminium alloys - Weldability, welding and testing (ISO
18595:2021)
Soudage par résistance - Soudage par points de Widerstandsschweißen - Punktschweißen von
l'aluminium et des alliages d'aluminium - Soudabilité, Aluminium und Aluminiumlegierungen -
soudage et essais (ISO 18595:2021) Schweißeignung, Schweißen und Prüfungen (ISO
18595:2021)
This European Standard was approved by CEN on 30 January 2021.

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, Turkey 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
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 18595:2021 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 18595:2021) has been prepared by Technical Committee ISO/TC 44 "Welding
and allied processes" in collaboration with Technical Committee CEN/TC 121 “Welding and allied
processes” the secretariat of which is held by DIN.
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 August 2021, and conflicting national standards shall
be withdrawn at the latest by August 2021.
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 18595:2007.
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, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 18595:2021 has been approved by CEN as EN ISO 18595:2021 without any modification.

INTERNATIONAL ISO
STANDARD 18595
Second edition
2021-01
Resistance welding — Spot welding of
aluminium and aluminium alloys —
Weldability, welding and testing
Soudage par résistance — Soudage par points de l'aluminium et des
alliages d'aluminium — Soudabilité, soudage et essais
Reference number
ISO 18595:2021(E)
©
ISO 2021
ISO 18595:2021(E)
© ISO 2021
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 2021 – All rights reserved

ISO 18595:2021(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Material . 2
4.1 Form . 2
4.2 Types of aluminium alloys . 2
5 Surface conditions . 2
6 Edge distance, edge conditions, form of component and weld spacing .2
7 Electrodes . 3
7.1 Materials . 3
7.2 Dimensions . 3
7.3 Cooling electrodes . 4
8 Qualification of welds . 4
8.1 General . 4
8.2 Weldability test . 4
8.3 Pre-production tests . 4
8.4 Routine tests . 4
8.4.1 Type of tests . 4
8.4.2 Frequency of testing . 4
9 Weld quality requirements . 5
9.1 Weld diameter . 5
9.2 Weld dimensions . 5
9.3 Weld fracture mode . 5
9.4 Weld strength . 5
9.5 Weld appearance — Surface condition . 7
10 Multi-weld arrays . 8
Annex A (informative) Typical spot welding conditions .10
Annex B (informative) Non-exhaustive list of aluminium alloys covered by this document.11
Annex C (informative) Typical information to appear on a welding procedure sheet for spot
welding .13
Bibliography .15
ISO 18595:2021(E)
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 documents 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).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
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 44, Welding and allied processes,
Subcommittee SC 6, Resistance welding and allied mechanical joining, in collaboration with the European
Committee for Standardization (CEN) Technical Committee CEN/TC 121, Welding and allied processes,
in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 18595:2007), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— new Clause 3 Terms and definitions has been added;
— the whole document has been technically revised to the state of the art;
— Annex C has been revised.
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.
Official interpretations of ISO/TC 44 documents, where they exist, are available from this page: https://
committee .iso .org/ sites/ tc44/ home/ interpretation .html.
iv © ISO 2021 – All rights reserved

INTERNATIONAL STANDARD ISO 18595:2021(E)
Resistance welding — Spot welding of aluminium and
aluminium alloys — Weldability, welding and testing
1 Scope
This document specifies requirements for resistance spot welding in the fabrication of assemblies of
aluminium sheet, extrusions (both work- and age-hardening alloys) and/or cast material comprising
two or three thicknesses of metal, where the maximum single (sheet) thickness of components to be
welded is within the range 0,6 mm to 6 mm.
This document is applicable to the welding of sheets or plates of dissimilar thickness where the
thickness ratio is less than or equal to 3:1. It applies to the welding of three thicknesses where the total
thickness is less than or equal to 9 mm.
Welding with the following types of machines is within the scope of this document:
— pedestal welding machines;
— gun welders;
— automatic welding equipment where the components are fed by robots or automatic feeding
equipment;
— multi-welders;
— robotic welders.
Information on appropriate welding equipment is given in Annex A and on spot welding conditions in
Annex B. The latter are for guidance only and can require modification depending on service conditions
of the fabrication, type of welding equipment, characteristics of the secondary circuit, electrode
material and geometry.
The welding of coated material, e.g. zinc-coated or anodized material, is outside the scope of this
document.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 209, Aluminium and aluminium alloys — Chemical composition
ISO 669, Resistance welding — Resistance welding equipment — Mechanical and electrical requirements
ISO 3522, Aluminium and aluminium alloys — Castings — Chemical composition and mechanical properties
ISO 5182, Resistance welding — Materials for electrodes and ancillary equipment
ISO 5184, Straight resistance spot welding electrodes
ISO 5821, Resistance welding — Spot welding electrode caps
ISO 5830, Resistance spot welding — Male electrode caps
ISO 10447, Resistance welding — Testing of welds — Peel and chisel testing of resistance spot and
projection welds
ISO 18595:2021(E)
ISO 14273, Resistance welding — Destructive testing of welds — Specimen dimensions and procedure for
tensile shear testing resistance spot and embossed projection welds
ISO 15614-12, Specification and qualification of welding procedures for metallic materials — Welding
procedure test — Part 12: Spot, seam and projection welding
ISO 17677-1, Resistance welding — Vocabulary — Part 1: Spot, projection and seam welding
ISO 18278-2, Resistance welding — Weldability — Part 2: Evaluation procedures for weldability in
spot welding
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 669 and ISO 17677-1 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
4 Material
4.1 Form
The material shall be according to ISO 209 and ISO 3522.
4.2 Types of aluminium alloys
A partial list of aluminium alloys is given in Annex C.
5 Surface conditions
Prior to welding, all surfaces shall be checked for their suitability for spot welding. The surfaces should
preferably be free from oil, grease, lubricant, visible oxidation, paint, dirt or excessive scratches. If
necessary, appropriate surface treatment, e.g. chemical etching, shall be carried out. Unless specifically
developed for spot welding, mill-finish surfaces are generally not suitable for spot welding and can need
pre-treatment. Die-cast material shall be free from excessive surface roughness and imperfections,
e.g. as caused by washing out of the die material. Aluminium manufacturers and component suppliers
can produce surface-treated material suitable for spot welding, e.g. with TiZr conversion coating.
In addition, coated material can be supplied with chromate or phosphate passivation. Phosphated
aluminium may be used in certain applications. Excessive quantities of dissolved gases in die-cast
material shall be avoided. These materials can be spot welded, although adjustment of the welding
parameters is generally necessary as outlined in Annex B.
In all cases, the surface condition and any surface treatment shall be recorded in the testing
documentation.
The stability of surface condition can be evaluated by measuring the transition resistance in accordance
with ISO 18594.
6 Edge distance, edge conditions, form of component and weld spacing
The components to be welded shall be free from burrs or other defects, which can, in any way, interfere
with interface contact or require excessive force to fit the parts together.
2 © ISO 2021 – All rights reserved

ISO 18595:2021(E)
The shape of the component shall be such that there is satisfactory interfacial contact in the area where
welds are to be made. The distance from the edge of the component to the centre of the weld (edge
distance) shall be not less than 1,25 d (see Figure 2), where d is the target weld diameter as defined in
8.2. The use of edge distances smaller than the recommended values adversely influence weld quality.
Edge distances smaller than the recommended values should be used only when expressly specified.
In this case, the nominal weld diameter specified may be less than that given in 8.2, and therefore due
allowance needs to be made for a lower weld strength (see 9.4).
7 Electrodes
7.1 Materials
The electrode materials shall be copper alloy and should possess high thermal and electrical
conductivity. The electrode materials shall comply, and be used in accordance, with ISO 5182. If other
electrode materials are used, then these shall be recorded in the testing documentation.
7.2 Dimensions
The welding electrodes shall be of sufficient cross-sectional area and strength to carry the welding
current and electrode force without overheating, excessive deformation, or excessive deflection. If
possible, electrodes with a minimum shank diameter, D, of 20 mm should be used. If other electrode
diameters are used, then these shall be recorded in the testing documentation.
The electrode dimensions shall, where practicable, conform to ISO 5184 for straight electrodes,
ISO 5821 for female electrode caps, or ISO 5830 for male electrode caps, as applicable. In cases where
...