IEC 60068-2-20:2008

Environmental testing - Part 2-20: Tests - Test T: Test methods for solderability and resistance to soldering heat of devices with leads

IEC 60068-2-20:2008 outlines Test T, applicable to devices with leads. Soldering tests for surface mounting devices (SMD) are described in IEC 60068-2-58. This standard provides procedures for determining the solderability and resistance to soldering heat of devices in applications using solder alloys, which are eutectic or near eutectic tin lead (Pb), or lead-free alloys. The procedures in this standard include the solder bath method and soldering iron method. The objective of this standard is to ensure that component lead or termination solderability meets the applicable solder joint requirements of IEC 61191-3 and IEC 61191-4. In addition, test methods are provided to ensure that the component body can resist against the heat load to which it is exposed during soldering. The major technical changes with regard to the fourth edition are the following:
- the solder globule test is deleted;
- test conditions and requirements for lead-free solders are added.

Essais d'environnement - Partie 2-20: Essais - Essai T: Méthodes d'essai de la brasabilité et de la résistance à la chaleur de brasage des dispositifs à broches

La CEI 60068-2-20:2008 décrit l'essai T qui s'applique aux dispositifs à broches. Les essais de brasage des composants pour montage en surface (CMS) sont décrits dans la CEI 60068-2-58. La présente norme fournit des procédures pour déterminer la brasabilité et la résistance à la chaleur de brasage des dispositifs dans les applications utilisant des alliages de brasure, qui sont soit des brasures étain plomb (Pb) eutectique ou quasi eutectique, soit des alliages de brasure sans plomb. Les procédures de la présente norme incluent les méthodes dites de bain de brasage et de fer à braser. Le but de la présente norme est de s'assurer que les broches des composants ou la brasabilité de leurs extrémités est en mesure de satisfaire aux exigences applicables aux joints de brasures des CEI 61191-3 et 61191-4. De plus, des méthodes d'essai sont fournies pour s'assurer que le corps du composant peut résister à la charge calorifique à laquelle il est exposé pendant le brasage. Les principales modifications techniques par rapport à la quatrième édition sont les suivantes:
- l'essai de gouttelette de brasure est supprimé;
- des conditions et des exigences d'essai concernant les brasures sans plomb sont ajoutées.

General Information

• Status: Published
• Publication Date: 20-Jul-2008
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 19.040 - Environmental testing
• Technical Committee: TC 91 - Electronics assembly technology
• Drafting Committee: WG 3 - TC 91/WG 3
• Current Stage: DELPUB - Deleted Publication
• Start Date: 28-Feb-2018
• Completion Date: 30-Mar-2021

Relations

• Revised: IEC 60068-2-20:2021 - Environmental testing - Part 2-20: Tests - Test Ta and Tb: Test methods for solderability and resistance to soldering heat of devices with leads
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 60068-2-20
Edition 5.0 2008-07
INTERNATIONAL
STANDARD
Environmental testing –
Part 2-20: Tests – Test T: Test methods for solderability and resistance to
soldering heat of devices with leads

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form

or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,

please contact the address below or your local IEC member National Committee for further information.

IEC Central Office
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CH-1211 Geneva 20
Switzerland
Email: [e-mail]
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About the IEC
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International Standards for all electrical, electronic and related technologies.

About IEC publications
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IEC 60068-2-20
Edition 5.0 2008-07
INTERNATIONAL
STANDARD
Environmental testing –
Part 2-20: Tests – Test T: Test methods for solderability and resistance to
soldering heat of devices with leads

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
R
ICS 19.040 ISBN 2-8318-9919-2
– 2 – 60068-2-20 © IEC:2008(E)

CONTENTS
FOREWORD.4

1 Scope and object.6

2 Normative references .6

3 Terms and definitions .7

4 Test Ta: Solderability of wire and tag terminations.8

4.1 Object and general description of the test.8

4.1.1 Test methods.8

4.1.2 Specimen preparation.8
4.1.3 Initial measurements .9
4.1.4 Accelerated ageing.9
4.2 Method 1: Solder bath .9
4.2.1 Description of the solder bath .9
4.2.2 Flux .10
4.2.3 Procedure.10
4.2.4 Test conditions .10
4.2.5 Final measurements and requirements .11
4.3 Method 2: Soldering iron at 350 °C.11
4.3.1 Description of soldering irons .11
4.3.2 Solder and flux .12
4.3.3 Procedure.12
4.3.4 Final measurements and requirements .13
4.4 Information to be given in the relevant specification .13
5 Test Tb: Resistance to soldering heat.13
5.1 Object and general description of the test.13
5.1.1 Test methods.13
5.1.2 Initial measurements .14
5.2 Method 1: Solder bath .14
5.2.1 Description of the solder bath .14
5.2.2 Flux .14
5.2.3 Procedure.14
5.2.4 Test conditions .14
5.2.5 De-wetting .15

5.3 Method 2: Soldering iron .15
5.3.1 Description of soldering iron .15
5.3.2 Solder and flux .15
5.3.3 Procedure.15
5.4 Recovery.16
5.5 Final measurements and requirements .16
5.6 De-wetting (if applicable).16
5.7 Information to be given in the relevant specification .17
Annex A (informative) Example of apparatus for accelerated steam ageing process .18
Annex B (normative) Specification for flux constituents .19
Bibliography.20

Figure 1 – Diagram of contact angle .7

60068-2-20 © IEC:2008(E) – 3 –

Figure 2 – Position of soldering iron.12

Figure A.1 – Example of apparatus .18

Table 1 – Solderability, Solder bath method: Test severities (duration and temperature).11

Table 2 – Resistance to soldering heat, Solder bath method: Test severities (duration

and temperature) .15

– 4 – 60068-2-20 © IEC:2008(E)

INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
ENVIRONMENTAL TESTING –
Part 2-20: Tests –
Test T: Test methods for solderability

and resistance to soldering heat of devices with leads

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

International Standard IEC 60068-2-20 has been prepared by IEC technical committee 91:
Electronics assembly technology.
This fifth edition cancels and replaces the fourth edition, published in 1979 and its
Amendment 2 (1987). Amendment 2 includes Amendment 1. This fifth edition constitutes a
technical revision and includes test conditions and requirements for use of lead-free solder.
The major technical changes with regard to the fourth edition are the following:
– the solder globule test is deleted;
– test conditions and requirements for lead-free solders are added.

60068-2-20 © IEC:2008(E) – 5 –

The text of this standard is based on the following documents:

FDIS Report on voting
91/764/FDIS 91/774/RVD
Full information on the voting for the approval of this standard can be found in the report on

voting indicated in the above table.

This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

A list of all the parts in the IEC 60068 series, under the general title Environmental testing,
can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in
the data related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

– 6 – 60068-2-20 © IEC:2008(E)

ENVIRONMENTAL TESTING –
Part 2-20: Tests –
Test T: Test methods for solderability

and resistance to soldering heat of devices with leads

1 Scope and object
This part of IEC 60068 outlines Test T, applicable to devices with leads. Soldering tests for
surface mounting devices (SMD) are described in IEC 60068-2-58.
This standard provides procedures for determining the solderability and resistance to
soldering heat of devices in applications using solder alloys, which are eutectic or near
eutectic tin lead (Pb), or lead-free alloys.
The procedures in this standard include the solder bath method and soldering iron method.
The objective of this standard is to ensure that component lead or termination solderability
meets the applicable solder joint requirements of IEC 61191-3 and IEC 61191-4. In addition,
test m
...

IEC 60068-2-20 ®
Edition 5.0 2008-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Environmental testing –
Part 2-20: Tests – Test T: Test methods for solderability and resistance to
soldering heat of devices with leads

Essais d’environnement –
Partie 2-20: Essais – Essai T: Méthodes d'essai de la brasabilité et de la
résistance à la chaleur de brasage des dispositifs à broches

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by
any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either IEC or
IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,
please contact the address below or your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite
ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie
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publication, utilisez les coordonnées ci-après ou contactez le Comité national de la CEI de votre pays de résidence.

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Switzerland
Email: [e-mail]
Web: www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.
ƒ Catalogue of IEC publications: www.iec.ch/searchpub
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in English and French, with equivalent terms in additional languages. Also known as the International Electrotechnical
Vocabulary online.
ƒ Customer Service Centre: www.iec.ch/webstore/custserv
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IEC 60068-2-20 ®
Edition 5.0 2008-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Environmental testing –
Part 2-20: Tests – Test T: Test methods for solderability and resistance to
soldering heat of devices with leads

Essais d’environnement –
Partie 2-20: Essais – Essai T: Méthodes d'essai de la brasabilité et de la
résistance à la chaleur de brasage des dispositifs à broches

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
R
CODE PRIX
ICS 19.040 ISBN 978-2-88910-037-8
– 2 – 60068-2-20 © IEC:2008
CONTENTS
FOREWORD.4
1 Scope and object.6
2 Normative references .6
3 Terms and definitions .7
4 Test Ta: Solderability of wire and tag terminations.8
4.1 Object and general description of the test.8
4.1.1 Test methods.8
4.1.2 Specimen preparation.8
4.1.3 Initial measurements .9
4.1.4 Accelerated ageing.9
4.2 Method 1: Solder bath .9
4.2.1 Description of the solder bath .9
4.2.2 Flux .10
4.2.3 Procedure.10
4.2.4 Test conditions .10
4.2.5 Final measurements and requirements .11
4.3 Method 2: Soldering iron at 350 °C.11
4.3.1 Description of soldering irons .11
4.3.2 Solder and flux .12
4.3.3 Procedure.12
4.3.4 Final measurements and requirements .13
4.4 Information to be given in the relevant specification .13
5 Test Tb: Resistance to soldering heat.13
5.1 Object and general description of the test.13
5.1.1 Test methods.13
5.1.2 Initial measurements .14
5.2 Method 1: Solder bath .14
5.2.1 Description of the solder bath .14
5.2.2 Flux .14
5.2.3 Procedure.14
5.2.4 Test conditions .14
5.2.5 De-wetting .15
5.3 Method 2: Soldering iron .15
5.3.1 Description of soldering iron .15
5.3.2 Solder and flux .15
5.3.3 Procedure.15
5.4 Recovery.16
5.5 Final measurements and requirements .16
5.6 De-wetting (if applicable).16
5.7 Information to be given in the relevant specification .17
Annex A (informative) Example of apparatus for accelerated steam ageing process .18
Annex B (normative) Specification for flux constituents .19
Bibliography.20

Figure 1 – Diagram of contact angle .7

60068-2-20 © IEC:2008 – 3 –
Figure 2 – Position of soldering iron.12
Figure A.1 – Example of apparatus .18

Table 1 – Solderability, Solder bath method: Test severities (duration and temperature).11
Table 2 – Resistance to soldering heat, Solder bath method: Test severities (duration
and temperature) .15

– 4 – 60068-2-20 © IEC:2008
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ENVIRONMENTAL TESTING –
Part 2-20: Tests –
Test T: Test methods for solderability
and resistance to soldering heat of devices with leads

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60068-2-20 has be
...