Soft soldering fluxes - Test methods - Part 16: Flux efficacy test, wetting balance method (ISO 9455-16:2013)

This part of ISO 9455 specifies a method for the assessment of the efficacy of a soft soldering flux, known as the wetting balance method. It gives a qualitative assessment of the comparative efficacy of two fluxes (for example, a standard and a test flux), based on their capacity to promote wetting of a metal surface by liquid solder. The method is applicable to all flux types in liquid form classified in ISO 9454-1.

Flussmittel zum Weichlöten - Prüfverfahren - Teil 16: Bestimmung der Wirksamkeit des Flussmittels, Verfahren zur Messung der Benetzungskraft (ISO 9455-16:2013)

Dieser Teil der ISO 9455 legt ein Verfahren zum Beurteilen der Wirksamkeit eines Flussmittels zum
Weichlöten fest, das als Verfahren zur Messung der Benetzungskraft bezeichnet wird. Es bietet eine
qualitative Beurteilung für den Vergleich der Wirksamkeit zweier Flussmittel (z. B. ein Standard-Flussmittel mit
einem zu prüfenden Flussmittel) hinsichtlich ihrer Fähigkeiten, die Benetzung einer Metalloberfläche durch ein
flüssiges Weichlot zu fördern. Das Verfahren ist für alle flüssigen Flussmitteltypen anwendbar, die in
ISO 9454-1 aufgeführt sind.
ANMERKUNG Es ist anzunehmen, dass zukünftige Entwicklungen, welche mit verbesserten Verfahren einen
reproduzierbaren Oberflächenbereich zum Prüfen ergeben, es möglich machen, dieses Verfahren zum Beurteilen der
Flussmittelwirksamkeit quantitativ einzusetzen. Aus diesem Grund sind verschiedene alternative Verfahren zur
Vorbereitung der Prüfstückoberfläche in der vorliegenden Norm enthalten.

Flux de brasage tendre - Méthodes d'essai - Partie 16: Essai d'efficacité du flux, méthode à la balance de mouillage (ISO 9455-16:2013)

L'ISO 9455-16:2013 spécifie une méthode pour l'évaluation de l'efficacité d'un flux de brasage tendre, connue sous le nom de méthode à la balance de mouillage. Elle permet une évaluation qualitative de l'efficacité comparée de deux flux faisant l'objet d'une comparaison (par exemple un flux de référence et un flux d'essai), évaluation fondée sur la capacité de ces flux à faciliter le mouillage de la surface d'un métal par le produit d'apport liquide. Cette méthode est applicable à tous les types de flux sous forme liquide classés dans l'ISO 9454-1.

Talila za mehko spajkanje - Preskusne metode - 16. del: Preskus učinkovitosti, postopek za merjenje omočljivosti (ISO 9455-16:2013)

Ta del ISO 9455 določa metodo za oceno učinkovitosti talila za mehko spajkanje, znano kot postopek za merjenje omočljivosti. Na osnovi zmogljivosti spodbujanja omočljivosti kovinske površine s tekočim talilom podaja kvalitativno oceno primerjalne učinkovitosti dveh talil (npr. standardnega in preskusnega talila). Ta metoda velja za vse vrste talil v tekoči obliki iz ISO 9454-1.

General Information

Status
Withdrawn
Public Enquiry End Date
24-Jun-2011
Publication Date
04-Jul-2013
Withdrawal Date
06-Nov-2019
Technical Committee
Current Stage
9900 - Withdrawal (Adopted Project)
Start Date
06-Nov-2019
Due Date
29-Nov-2019
Completion Date
07-Nov-2019

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Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 9455-16:2013
01-september-2013
1DGRPHãþD
SIST EN ISO 9455-16:2002
7DOLOD]DPHKNRVSDMNDQMH3UHVNXVQHPHWRGHGHO3UHVNXVXþLQNRYLWRVWL
SRVWRSHN]DPHUMHQMHRPRþOMLYRVWL ,62
Soft soldering fluxes - Test methods - Part 16: Flux efficacy test, wetting balance method
(ISO 9455-16:2013)
Flussmittel zum Weichlöten - Prüfverfahren - Teil 16: Bestimmung der Wirksamkeit des
Flussmittels, Verfahren zur Messung der Benetzungskraft (ISO 9455-16:2013)
Flux de brasage tendre - Méthodes d'essai - Partie 16: Essai d'efficacité du flux,
méthode à la balance de mouillage (ISO 9455-16:2013)
Ta slovenski standard je istoveten z: EN ISO 9455-16:2013
ICS:
25.160.50 Trdo in mehko lotanje Brazing and soldering
SIST EN ISO 9455-16:2013 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 9455-16:2013

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SIST EN ISO 9455-16:2013


EUROPEAN STANDARD
EN ISO 9455-16

NORME EUROPÉENNE

EUROPÄISCHE NORM
April 2013
ICS 25.160.50 Supersedes EN ISO 9455-16:2001
English Version
Soft soldering fluxes - Test methods - Part 16: Flux efficacy test,
wetting balance method (ISO 9455-16:2013)
Flux de brasage tendre - Méthodes d'essai - Partie 16: Flussmittel zum Weichlöten - Prüfverfahren - Teil 16:
Essai d'efficacité du flux, méthode à la balance de Bestimmung der Wirksamkeit des Flussmittels, Verfahren
mouillage (ISO 9455-16:2013) zur Messung der Benetzungskraft (ISO 9455-16:2013)
This European Standard was approved by CEN on 2 February 2013.

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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2013 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 9455-16:2013: E
worldwide for CEN national Members.

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SIST EN ISO 9455-16:2013
EN ISO 9455-16:2013 (E)
Contents Page
Foreword .3
2

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SIST EN ISO 9455-16:2013
EN ISO 9455-16:2013 (E)
Foreword
This document (EN ISO 9455-16:2013) has been prepared by Technical Committee ISO/TC 44 "Welding and
allied processes" in collaboration with Technical Committee CEN/TC 121 “Welding” 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 October 2013, and conflicting national standards shall be withdrawn at
the latest by October 2013.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 9455-16:2001.
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, Former Yugoslav Republic of Macedonia, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
Endorsement notice
The text of ISO 9455-16:2013 has been approved by CEN as EN ISO 9455-16:2013 without any modification.

3

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SIST EN ISO 9455-16:2013

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SIST EN ISO 9455-16:2013
INTERNATIONAL ISO
STANDARD 9455-16
Second edition
2013-04-15
Soft soldering fluxes — Test methods —
Part 16:
Flux efficacy test, wetting balance
method
Flux de brasage tendre — Méthodes d’essai —
Partie 16: Essai d’efficacité du flux, méthode à la balance de mouillage
Reference number
ISO 9455-16:2013(E)
©
ISO 2013

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SIST EN ISO 9455-16:2013
ISO 9455-16:2013(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2013
All rights reserved. Unless otherwise specified, 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
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2013 – All rights reserved

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SIST EN ISO 9455-16:2013
ISO 9455-16:2013(E)

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Symbols . 1
4 Principle . 2
5 Reagents . 2
6 Apparatus . 2
7 Test pieces . 3
8 Procedure. 3
8.1 Preparation of the test pieces. 3
8.2 Test method . 3
9 Reference value using standard flux . 4
10 Presentation of results . 4
11 Calculation and expression of results . 6
12 Test report . 7
Annex A (normative) Method for the preparation of standard rosin (colophony) based liquid
fluxes having 25 % (by mass) non-volatile content
. 8
Annex B (normative) Method for the production of test pieces with a controlled-contaminated
surface for the wetting balance test (artificial sulfidation method) .10
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SIST EN ISO 9455-16:2013
ISO 9455-16:2013(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International
Standards adopted by the technical committees are circulated to the member bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the member bodies
casting a vote.
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.
ISO 9455-16 was prepared by Technical Committee ISO/TC 44, Welding and allied processes, Subcommittee
SC 12, Soldering materials.
This second edition cancels and replaces the first edition (ISO 9455-16:1998), which has been
technically revised.
ISO 9455 consists of the following parts, under the general title Soft soldering fluxes — Test methods:
— Part 1: Determination of non-volatile matter, gravimetric method
— Part 2: Determination of non-volatile matter, ebulliometric method
— Part 3: Determination of acid value, potentiometric and visual titration methods
— Part 5: Copper mirror test
— Part 6: Determination and detection of halide (excluding fluoride) content
— Part 8: Determination of zinc content
— Part 9: Determination of ammonia content
— Part 10: Flux efficacy test, solder spread method
— Part 11: Solubility of flux residues
— Part 13: Determination of flux spattering
— Part 14: Assessment of tackiness of flux residues
— Part 15: Copper corrosion test
— Part 16: Flux efficacy test, wetting balance method
— Part 17: Surface insulation resistance comb test and electrochemical migration test of flux residues
Requests for official interpretations of any aspect of this part of ISO 9455 should be directed to the
Secretariat of ISO/TC 44/SC 12 via your national standards body. A complete listing of these bodies can
be found at www.iso.org.
iv © ISO 2013 – All rights reserved

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SIST EN ISO 9455-16:2013
INTERNATIONAL STANDARD ISO 9455-16:2013(E)
Soft soldering fluxes — Test methods —
Part 16:
Flux efficacy test, wetting balance method
1 Scope
This part of ISO 9455 specifies a method for the assessment of the efficacy of a soft soldering flux, known
as the wetting balance method. It gives a qualitative assessment of the comparative efficacy of two
fluxes (for example, a standard and a test flux), based on their capacity to promote wetting of a metal
surface by liquid solder. The method is applicable to all flux types in liquid form classified in ISO 9454-1.
NOTE It is hoped that future developments using improved techniques for obtaining a reproducible range
of test surfaces will enable this method for assessing flux efficacy to be quantitative. For this reason, several
alternative procedures for preparing the surface of the test piece are included in the present method.
2 Normative references
The following referenced documents are indispensable for the application 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 9453, Soft solder alloys — Chemical compositions and forms
ISO 9454-1, Soft soldering fluxes — Classification and requirements — Part 1: Classification, labelling
and packaging
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 60068-2-54, Environmental testing — Part 2-54: Tests — Test Ta: Solderability testing of electronic
components by the wetting balance method
IEC 60068-2-78:2001, Environmental testing — Part 2-78: Tests; Test Cab: Damp heat, steady state
3 Symbols
d depth of immersion, in millimetres, of the test piece below the undisturbed solder level
A cross sectional area, in square millimetres, of the test piece at the solder line
ρ density, in grams per millilitre, of the solder under test at the test temperature
F wetting force, in millinewtons
t time at which the test piece first makes contact with the surface of the liquid solder in the bath
0
t time at which the solder starts to wet the test piece (point A, see Figure 1), at which point the
1
trace begins to fall
t time at which the recorded force is equal to the upward force due to buoyancy
2
t time at which the trace crosses the reference line
3
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SIST EN ISO 9455-16:2013
ISO 9455-16:2013(E)

4 Principle
The efficacy of the liquid flux under test is compared with that of a standard liquid flux, using a wetting
balance in conjunction with a specified test piece, appropriate to the class of flux under test.
5 Reagents
Use only reagents of recognized analytical quality and only distilled or deionized water.
5.1 Acid cleaning solution, prepared as follows:
Add cautiously, while stirring, 75 ml of sulfuric acid (ρ = 1,84 g/ml) to 210 ml of water and mix. Cool the
solution to room temperature. Add 15 ml of nitric acid (ρ = 1,42 g/ml) and mix thoroughly.
5.2 Acetone.
5.3 Propan-2-ol, complying with the following requirements:
— propan-2-ol: 99,5 % (by mass) minimum;
— acid content: 0,002 % (by mass) maximum;
— non-volatile content: 0,2 % (by mass) maximum.
Isopropyl alcohol (also propan-2-ol, 2-propanol or the abbreviation IPA) is a common name for this
chemical compound, which has the molecular formula C H O.
3 8
6 Apparatus
Usual laboratory apparatus and, in particular, the following.
6.1 Wetting balance and ancillary instrumentation, as described in IEC 60068-2-54.
Calibrate the apparatus in accordance with the manufacturer’s instructions.
6.2 Solder bath.
As a minimum, the bath temperature shall be capable of being maintained at a temperature corresponding
to the liquidus temperature of the alloy under test plus 35 °C. The test temperature shall be reported in
the test report.
The dimensions of the solder bath shall be such that no portion of the test piece (see Clause 7) is less than
15 mm from the wall of the bath and the depth of the liquid solder in the bath shall be not less than 30 mm.
The solder used for the test and the test temperature shall be one of the following:
— Sn60Pb40 (see ISO 9453) at 235 °C ± 3 °C;
— Sn96,5Ag3,0Cu0,5 (see ISO 9453) at 255 °C ± 3 °C;
— any other solder and temperature combinations as agreed between the customer and the flux supplier.
6.3 Acid-free filter paper.
2 © ISO 2013 – All rights reserved

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SIST EN ISO 9455-16:2013
ISO 9455-16:2013(E)

7 Test pieces
The test pieces shall be made of copper.
EXAMPLE Test pieces are cut from a rectangular copper sheet. The dimensions of each test piece are as follows:
— width: 10,0 mm ± 0,1 mm;
— length: constant between 15 mm and 30 mm, to suit the equipment used;
— thickness: either 0,10 mm ± 0,02 mm or 0,30 mm ± 0,05 mm.
When testing fluxes of type 1 or 2 (as defined in ISO 9454-1), full details of the test pieces shall be given
in the test report.
The sheet or other article used for preparing the test pieces shall be clean and free from contamination.
In order to obtain accurate results, the test pieces shall be cut cleanly without leaving significant burrs.
8 Procedure
8.1 Preparation of the test pieces
8.1.1 Cleaning
The test pieces shall be handled with clean tongs throughout. Select sufficient test pieces (see Clause 7)
to allow 10 per test flux and 10 per standard flux. Degrease them in acetone (5.2) and allow to dry.
Immerse them for 20 s in the acid cleaning solution (5.1) at room temperature. Remove the test pieces
from the acid cleaning solution and wash for about five seconds under running tap water. Rinse with
distilled or deionized water then acetone (5.2) and dry with acid-free filter paper (6.3).
If required, the test pieces may be stored in acetone after rinsing them in deionized water. When needed,
they shall be removed from the acetone and dried with acid-free filter paper (6.3).
Subject all the test pieces to one of the ageing procedures given in 8.1.2 to 8.1.4 as agreed between the
flux supplier and the customer.
8.1.2 Ageing the surface by sulfidation process
Carry out the procedure given in Annex B on all the cleaned test pieces (see 8.1.1).
8.1.3 Steam ageing the surface
Carry out the steam ageing procedure given in IEC 60068-2-20:2008, 4.1.1, ageing procedure 1b, for a
period of 4 h on all the cleaned test pieces (see 8.1.1).
8.1.4 Damp-heat, steady-state ageing
Subject all the cleaned pieces (see 8.1.1) to the test chamber conditions specified in IEC 60068-2-78:2001,
Clause 4, for a period selected from 1 h, 4 h or 24 h.
8.2 Test method
8.2.1 Carry out the following test procedure on each of the 10 test pieces. Complete all 10 tests within
45 min of the preparation stage (see 8.1).
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SIST EN ISO 9455-16:2013
ISO 9455-16:2013(E)

8.2.2 If the flux under test is of type 1 or type 2 (as defined in ISO 9454-1), maintain the temperature of
the solder bath at 235 °C ± 3 °C or 255 °C ± 3 °C (see 6.2).
When testing fluxes which are not type 1 or type 2 (as defined in ISO 9454-1), the bath temperature
requirements and the standard flux to be used for comparison shall be agreed between the flux supplier
and the customer.
8.2.3 Remove one of the test pieces from the acetone, dry it between two sheets of acid-free filter paper
(6.3) and place it in the wetting balance specimen clip so that the long edges are vertical. Dip the test
piece in the flux solution under test at room temperature, to a depth of no less than 3 mm greater than the
depth selected for immersion of the test piece in the solder (see 8.2.5). Avoid excess flux by withdrawing
the test piece cornerwise from the flux. If excess flux is still visible, touch the corner of the test piece on
clean filter paper.
8.2.4 Attach the specimen clip to the wetting balance, ensuring that the bottom edge of the test piece
is horizontal and approximately 20 mm above the solder bath (6.2). Allow it to remain there for 20 s± 5 s
so that the solvent in the flux can evaporate before the test commences. Some types of flux might require
a drying time which is shorter or longer than 20 s± 5 s. In these cases, the drying time shall be agreed
between the flux supplier and the customer. During this drying period, adjust the suspension force signal
and recorder trace to the desired zero position.
Immediately before starting the test, scrape the surface of the solder bath with a blade of suitable
material to remove oxides.
8.2.5 Either by raising the solder bath or by lowering the test piece, dip the test piece into the molten
solder at a speed of 20 mm/s ± 5 mm/s to a depth of either 3 mm ± 0,2 mm or 4 mm ± 0,2 mm.
Hold the test piece in this position for 5 s to 10 s and then withdraw it at a speed of 20 mm/s ± 5 mm/s.
Record the wetting force against time for the period during which the test piece is in contact with the solder.
8.2.6 Repeat operations 8.2.2 to 8.2.5 for each of the remaining nine test pieces.
9 Reference value using standard flux
Carry out the procedure described in Clause 8 using a further 10 test pieces (see Clause 7) but using a
standard flux instead of the flux under test. If the flux under test is of type 1 or type 2 (as defined in
ISO 9454-1), the standard flux prepared as described in Annex A may be used. If the flux under test is
of type 1.1.1 or 1.2.1 (as defined in ISO 9454-1), use the standard flux prepared as described in A.5.1. If
the flux under test is of type 1.1.2, 1.1.3, 1.2.2 or 1.2.3 (as defined in ISO 9454-1), use the standard flux
prepared as described in A.5.2.
If the flux under test is not of type 1 or type 2, use a standard flux as agreed upon by the supplier and
customer (see 8.2.2, second paragraph).
10 Presentation of results
A typical trace of wetting force against time is given in Figure 1.
In Figure 1, non-wetting (upward) forces are shown as negative and wetting (downward) forces as positive.
4 © ISO 2013 – All rights reserved

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SIST EN ISO 9455-16:2013
ISO 9455-16:2013(E)

Key
F force
t time
a
Test piece buoyancy line.
b
Wetting reference line.
Figure 1 — Recorded trace for wetting balance method showing significant points
The following are the points of significance in Figure 1.
— Time t is the moment at which the test piece first makes contact with the surface of the liquid
0
solder in the bath. It is indicated by a sharp deviation of the recorder trace from the zero-force line.
— Time t is the moment at which the solder starts to wet the test piece and corresponds to point A at
1
which the trace begins to fall.
— Time t , corresponding to point B, is the moment at which the recorded force is equal to the upward
2
force due to buoyancy. The position of the test piece buoyancy line is calculated from the density of
the solder and the depth of immersion of the test piece as follows.
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SIST EN ISO 9455-16:2013
ISO 9455-16:2013(E)

Force at point B, in millinewtons, is equal to
ρdA × 9,81/1 000
where
d is the depth of immersion, in millimetres, of the test piece below the undisturbed solder
level;
A is the cross-sectional area, in square millimetres, of the test piece at the solder line;
ρ is the density, in grams per millilitre, of the solder under test at the test temperature.
Time t is the moment at which the trace crosses the reference line. The line is drawn at a distance
3
corresponding to a force, F, which depends on the test piece thickness and the immersion depth, as
given in Table 1.
Table 1 — Values of the wetting force as a function of test piece thickness and depth of immersion
Thickness Immersion depth Force F
mm mm mN
0,1 3 5,23
0,3 3 5,01
0,1 4 5,17
0,3 4 4,85
NOTE The force F is equal to 2/3 of the theoretical maximum wetting force on the test
piece, assuming a wetting angle of zero and a liquid/vapour surface tension of 0,4 mN/mm.
Point C corresponds to the maximum value of the wetting force attained during the specified
immersion period.
Point D corresponds to the end of the specified immersion period.
11 Calculation and expression of results
11.1 Carry out the operations and calculations described in 11.2 and 11.3.
11.2 For each of the 10 recorded traces obtained for the sample flux, draw the test piece buoyancy line
through point B (see Clause 10) and draw the wetting reference line 5,6 mN below the buoyancy line (see
Figure 1). Read off the following times, in seconds:
a) the time between t and t (i.e. the time to the start of wetting);
0 1
b) the time between t and t (i.e. the time to reach a wetting force of 5,6 mN).
0 3
Calculate the mean values for a) and b) obtained from the 10 traces.
Measure the force corresponding to point C (i.e. the maximum wetting force). Calculate the mean value
of the maximum wetting force.
11.3 Repeat the operations and calculations described in 11.2 for the 10 recorder traces obtained from
the standard flux in order to obtain the mean values for a), b) and c) for the standard flux.
Compare the mean results for 11.2 a), b) and c) obtained for the flux under test with those obtained from
the 10 results using the standard flux.
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SIST EN ISO 9455-16:2013
ISO 9455-16:2013(E)

Hence assess the efficacy of the flux under test as:
— better than,
— as good as,
— worse than
the standard flux, in relation to the speed and strength of wetting.
12 Test report
The test report shall include the following information:
a) the identification of the sample tested, including copper test specification, identification number
and flux identifiers;
b) the test method used (a reference to this part of ISO 9455, i.e. ISO 9455-16:2013);
c) the test piece dimensions and, when fluxes of type 1 or type 2 were tested, full details of the test
pieces (see Clause 6);
d) the ageing treatment (see 8.1.2 to 8.1.4);
e) the test temperature (see 5.2);
f) the depth of immersion of the test piece in the molten solder (see 8.2.5);
g) details of the standard flux used for comparison;
h) the results obtained;
i) the nominal temperature range during the test and the actual temperature range recorded
during the test;
j) any unusual features noted during the procedure;
k) details of any operation not specified in the method, or any optional operation which might have
influenced the results;
l) the date of the test.
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SIST EN ISO 9455-16:2013
ISO 9455-16:2013(E)

Annex A
(normative)

Method for the preparation of standard rosin (colophony) based
liquid fluxes having 25 % (by mass) non-volatile content
A.1 General
This annex gives a method for the preparation of two standard rosin (colophony) based liquid fluxes
having 25 % (by mass) non-volatile content, one non-activated and the other halogen-activated (i.e.
type 1.1.1.A and type 1.1.2.A, as defined in ISO 9454-1, respectively). The specifications for the flux
constituents are based on IEC 60068-2-20:2008, Annex B.
The standard flux may be used as a reference against which the efficacy of the flux under test may be
compared (see Clauses 4 and 9).
A.2 Principle
The non-activated flux is prepared by dissolving a special grade of rosin (colophony) in propan-2-ol. The
halogen-activated flux is prepared in a similar way, with the addition of diethylamine hydrochloride.
A.3 Apparatus
Ordinary laboratory apparatus, including an oven for use at 110 °C ± 2 °C, is required.
A.4 Reagents
Use only reagents of recognized analytical grade.
A.4.1 Rosin (colophony), water white grade gum rosin, or equivalent, complying with the following
requirements:
— acid value: 155 mg KOH/g to 180 mg KOH/g;
— softening point: 70 °C minimum;
— flow point: 76 °C minimum;
— ash: 0,05 % maximum;
— solubility: to give a clear 1:1 solution in propan-2-ol.
A.4.2 Diethylamine hydrochloride, dried for 2 h at 110 °C ± 2 °C.
A.4.3 Propan-2-ol, see 5.3.
A.5 Procedure
A.5.1 Non-activated rosin
Weigh out 25 g ± 0,1 g of rosin (A.4.1) and dissolve it with gentle mixing in 75 g ± 0,1 g of propan-2-ol (A.4.3).
8 © ISO 2013 – All rights reserved

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SIST EN ISO 9455-16:2013
ISO 9455-16:2013(E)

A.5.2 Halogen-activated rosin
Weigh 0,39 g ± 0,01 g of diethylamine hydrochloride (A.4.2) and dissolve it in 75 g ± 0,1 g of propan-2-ol
(A.4.3). Then add 25 g ± 0,1 g of rosin (A.4.1) and dissolve it with gentle mixing. This flux solution contains
0,5 % (by mass) of active chloride.
A.6 Storage
The standard flux solutions prepared as described in Clause A.5 shall be stored in a container, properly
closed at all times, away from heat
...

SLOVENSKI STANDARD
oSIST prEN ISO 9455-16:2011
01-junij-2011
7DOLOD]DPHKNRVSDMNDQMH3UHVNXVQHPHWRGHGHO3UHVNXVXþLQNRYLWRVWL
SRVWRSHN]DPHUMHQMHRPRþOMLYRVWL ,62',6
Soft soldering fluxes - Test methods - Part 16: Flux efficacy test, wetting balance method
(ISO/DIS 9455-16:2011)
Flussmittel zum Weichlöten - Prüfverfahren - Teil 16: Bestimmung der Wirksamkeit des
Flussmittels, Verfahren zur Messung der Benetzungskraft (ISO/DIS 9455-16:2011)
Flux de brasage tendre - Méthodes d'essai - Partie 16: Essai d'efficacité du flux,
méthode à la balance de mouillage (ISO/DIS 9455-16:2011)
Ta slovenski standard je istoveten z: prEN ISO 9455-16
ICS:
25.160.50 Trdo in mehko lotanje Brazing and soldering
oSIST prEN ISO 9455-16:2011 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 9455-16:2011

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oSIST prEN ISO 9455-16:2011


EUROPEAN STANDARD
DRAFT
prEN ISO 9455-16
NORME EUROPÉENNE

EUROPÄISCHE NORM

April 2011
ICS 25.160.50 Will supersede EN ISO 9455-16:2001
English Version
Soft soldering fluxes - Test methods - Part 16: Flux efficacy test,
wetting balance method (ISO/DIS 9455-16:2011)
Flux de brasage tendre - Méthodes d'essai - Partie 16: Flussmittel zum Weichlöten - Prüfverfahren - Teil 16:
Essai d'efficacité du flux, méthode à la balance de Bestimmung der Wirksamkeit des Flussmittels, Verfahren
mouillage (ISO/DIS 9455-16:2011) zur Messung der Benetzungskraft (ISO/DIS 9455-16:2011)
This draft European Standard is submitted to CEN members for parallel enquiry. It has been drawn up by the Technical Committee
CEN/TC 121.

If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.

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.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.


EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2011 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN ISO 9455-16:2011: E
worldwide for CEN national Members.

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oSIST prEN ISO 9455-16:2011
prEN ISO 9455-16:2011 (E)
Contents Page
Foreword .3

2

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oSIST prEN ISO 9455-16:2011
prEN ISO 9455-16:2011 (E)
Foreword
This document (prEN ISO 9455-16:2011) has been prepared by Technical Committee ISO/TC 44 "Welding
and allied processes" in collaboration with Technical Committee CEN/TC 121 “Welding” the secretariat of
which is held by DIN.
This document is currently submitted to the parallel Enquiry.
This document will supersede EN ISO 9455-16:2001.
Endorsement notice
The text of ISO/DIS 9455-16:2011 has been approved by CEN as a prEN ISO 9455-16:2011 without any
modification.

3

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oSIST prEN ISO 9455-16:2011

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oSIST prEN ISO 9455-16:2011

DRAFT INTERNATIONAL STANDARD ISO/DIS 9455-16
ISO/TC 44/SC 12 Secretariat: DIN
Voting begins on Voting terminates on

2011-04-21 2011-09-21
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION  •  МЕЖДУНАРОДНАЯ ОРГАНИЗАЦИЯ ПО СТАНДАРТИЗАЦИИ  •  ORGANISATION INTERNATIONALE DE NORMALISATION


Soft soldering fluxes — Test methods —
Part 16:
Flux efficacy test, wetting balance method
Flux de brasage tendre — Méthodes d'essai —
Partie 16: Essai d'efficacité du flux, méthode à la balance de mouillage
[Revision of first edition (ISO 9455-16:1998)]
ICS 25.160.50





ISO/CEN PARALLEL PROCESSING
This draft has been developed within the International Organization for Standardization (ISO), and
processed under the ISO-lead mode of collaboration as defined in the Vienna Agreement.
This draft is hereby submitted to the ISO member bodies and to the CEN member bodies for a parallel
five-month enquiry.
Should this draft be accepted, a final draft, established on the basis of comments received, will be
submitted to a parallel two-month approval vote in ISO and formal vote in CEN.

To expedite distribution, this document is cir culated as r eceived from the committee
secretariat. ISO Central Secretariat work of editing and text composition will be undertaken at
publication stage.
Pour accélérer la distribution, le présent document est distr ibué tel qu'il est par venu du
secrétariat du comité. Le travail de rédaction et de composition de texte ser a effectué au
Secrétariat central de l'ISO au stade de publication.



THIS DOCUMENT IS A DRAFT CIRCULATED FOR COMMENT AND APPROVAL. IT IS THEREFORE SUBJECT TO CHANGE AND MAY NOT BE
REFERRED TO AS AN INTERNATIONAL STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS BEING ACCEPTABLE FOR INDUSTRIAL, TECHNOLOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE TO 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.
©  International Organization for Standardization, 2011

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oSIST prEN ISO 9455-16:2011
ISO/DIS 9455-16

Copyright notice
This ISO document is a Draft International Standard and is copyright-protected by ISO. Except as permitted
under the applicable laws of the user’s country, neither this ISO draft nor any extract from it may be
reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic,
photocopying, recording or otherwise, without prior written permission being secured.
Requests for permission to reproduce should be addressed to either ISO at the address below or ISO’s
member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Reproduction may be subject to royalty payments or a licensing agreement.
Violators may be prosecuted.

ii © ISO 2011 – All rights reserved

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oSIST prEN ISO 9455-16:2011
ISO/DIS 9455-16
Contents Page
Foreword .iv
1 Scope.1
2 Normative references.1
3 Terms and definitions .1
4 Symbols and abbreviated terms .2
5 Principle.2
6 Reagents.2
6.1 Acid cleaning solution. .2
6.2 Acetone.2
7 Apparatus.2
7.1 Wetting balance and ancillary instrumentation, as described in IEC 60068-2-54.2
7.2 Solder bath.2
7.3 Acid-free filter paper .3
8 Test pieces .3
9 Procedure.3
9.1 Preparation of the test pieces .3
9.2 Test method .4
10 Reference value using standard flux.4
11 Presentation of results.4
12 Expression of results.6
13 Test report.7
Annex A (normative) Method for the preparation of standard reference rosin (colophony) based
liquid fluxes having 25 % (m/m) non-volatile content .8
A.1 General .8
A.2 Principle.8
A.3 Apparatus.8
A.4 Reagents.8
A.5 Procedure.9
A.6 Storage .9
Annex B (normative) Method for the production of a controlled contaminated surface sample for
the wetting balance test (artificial sulfidation method).10
B.1 Copper samples for the artificial sulfidation method .10
B.2 Controlled contamination.16

© ISO 2011 – All rights reserved iii

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oSIST prEN ISO 9455-16:2011
ISO/DIS 9455-16
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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 9455-16 was prepared by Technical Committee ISO/TC 44, Welding and allied processes, Subcommittee
SC 12, .
This second/third/. edition cancels and replaces the first/second/. edition (ISO 9455-16:1998-12), [clause(s)
/ subclause(s) / table(s) / figure(s) / annex(es)] of which [has / have] been technically revised.
ISO 9455 consists of the following parts, under the general title Soft soldering fluxes — Test methods:
⎯ Part 16: Flux efficacy tests, wetting balance method
iv © ISO 2011 – All rights reserved

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oSIST prEN ISO 9455-16:2011
ISO/DIS 9455-16
Introduction

Requests for official interpretations of any aspect of this International Standard should be directed to the
Secretariat of ISO/TC 44/SC 12 via your national standards body. A complete listing of these bodies can be
found at www.iso.org.



© ISO 2011 – All rights reserved v

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oSIST prEN ISO 9455-16:2011

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oSIST prEN ISO 9455-16:2011
DRAFT INTERNATIONAL STANDARD ISO/DIS 9455-16

Soft soldering fluxes — Test methods —
Part 16:
Flux efficacy test, wetting balance method
1 Scope
This part of ISO 9455 specifies a method for the assessment of the efficacy of a soft soldering flux, known as
the wetting balance method. It gives a qualitative assessment of the comparative efficacy of two fluxes (for
example, a standard and a test flux), based on their capacity to promote wetting of a metal surface by liquid
solder. The method is applicable to all flux types in liquid form classified in ISO 9454-1.
NOTE It is hoped that future developments using improved techniques for obtaining a reproducible range of test
surfaces will enable this method for assessing flux efficacy to be quantitative. For this reason several alternative
procedures for preparing the surface of the test piece are included in the present method.
2 Normative references
The following referenced documents are indispensable for the application 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 1634-1:1987, Wrought copper and copper alloy plate, sheet and strip — Part1: Technical conditions of
delivery for plate, sheet, and strip for general purposes
ISO 9453, Soft solder alloys — Chemical compositions and forms
ISO 9454-1, Soft soldering fluxes— Classification and requirements— Part1: Classification, labelling and
packaging
IEC 60068-2-20:2008, Environmental testing — Part 2-20: Tests — Test T: Test methods for soldeability and
resistance to soldering heat of devices with leads
IEC 60068-2-54, Environmental testing — Part 2-54: Tests — Test Ta: Solderability testing of electronic
components by the wetting balance method
IEC 60068-2-78:2001, Environmental testing — Part 2-78: Tests; Test Cab: Damp heat, steady state
3 Terms and definitions
For the purposes of this document, the following term and definition apply.
3.1
Propan-2-ol
Isopropyl alcohol (also propan-2-ol, 2-propanol or the abbreviation IPA) is a common name for the chemical
compound with the molecular formula C H O
3 8
NOTE See Annex A.2
© ISO 2011 – All rights reserved 1

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oSIST prEN ISO 9455-16:2011
ISO/DIS 9455-16
4 Symbols and abbreviated terms
d is the depth of immersion, in millimetres, of the test piece below the undisturbed solder level;
a is the cross sectional area, in square millimetres, of the test piece at the solder line;
ρ is the density in g/ml of solder under test at the test temperature;
F is the wetting force, in mN;
t the time at which the test piece first makes contact with the surface of the liquid solder in the bath
0

t the moment at which the solder starts to wet the test piece and corresponds to point A at which
1
the trace begins to fall;

t The moment at which the recorded force is equal to the upward force due to buoyancy;
2

t The time at which the trace crosses the reference line.
3

5 Principle
The efficacy of the liquid flux under test is compared with that of a standard liquid flux using a wetting balance
in conjunction with a prescribed test piece, appropriate to the class of flux under test.
6 Reagents
In the test use only reagents of recognized analytical quality and only distilled or de-ionized water.
6.1 Acid cleaning solution.
Add cautiously, while stirring, 75 ml of sulphuric acid ( = 1,84 g/ml) to 210 ml of water and mix. Cool the
solution to room temperature. Add 15 ml of nitric acid ( = 1,42 g/ml) and mix thoroughly.
6.2 Acetone.
7 Apparatus
Usual laboratory apparatus and, in particular, the following.
7.1 Wetting balance and ancillary instrumentation, as described in IEC 60068-2-54.
NOTE The apparatus is to be calibrated in accordance with the manufacturer's instructions.
7.2 Solder bath
As a minimum the bath temperature shall be capable of being maintained at a set temperature of the liguidus
temperature of the alloy on the test plus 35 °C. The test temperature shall be documented.
The dimensions of the solder bath shall be such that no portion of the test piece (clause 8) is less than 15 mm
from the wall of the bath and the depth of the liquid solder in the bath shall be not less than 30 mm.
The solder used for the test and the test temperature shall be selected from one of the following:
2 © ISO 2011 – All rights reserved

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oSIST prEN ISO 9455-16:2011
ISO/DIS 9455-16
⎯ S-Sn60Pb40 (see ISO 9453) at (235 ± 3)°C;
⎯ S-Sn96Ag3Cu1 (see ISO 9453) at (255 ± 3)°C;
⎯ Any other solder or temperature combinations as agreed between the customer and the flux supplier.
7.3 Acid-free filter paper
8 Test pieces
Test pieces cut from a copper and of rectangular shape sheet are used. The dimensions of each test piece
shall be as follows:
⎯ width: (10,0 ± 0,1) mm;
⎯ length: constant between 15 mm and 30 mm, to suit the equipment used;
⎯ thickness either 0,10 mm ± 0,02 mm or 0,30 mm ± 0,05 mm.
When testing fluxes of type 1 or 2 (as defined in ISO 9454-1), the test pieces shall be cut from copper sheet
complying with ISO 1634-1: Grade Cu-ETP, temper HA.
The sheet used for preparing the test pieces shall be clean and free from contamination. In order to obtain
accurate results, the test pieces shall be cut cleanly without leaving significant burrs.
9 Procedure
9.1 Preparation of the test pieces
9.1.1 Cleaning
The test pieces shall be handled with clean tongs throughout. Select sufficient test pieces (see clause 8) to
allow ten per test flux and ten per standard flux. Degrease them in acetone (6.2) and allow to dry. Immerse
them for 20 s in the acid cleaning solution (6.1) at room temperature. Remove the test pieces from the acid
cleaning solution (6.1), wash for about five seconds under running tap water. Rinse with distilled or deionized
water then acetone (6.2) and dry with acid-free filter paper (7.3).
NOTE If required, the test pieces may be stored in acetone after rinsing them in deionized water. When needed they
should be removed from the acetone and dried with acid-free filter paper (7.3).
Subject all the test pieces to one of the ageing procedures given in 9.1.2 to 9.1.4. as agreed between the flux
supplier and the user.
9.1.2 Ageing the surface by sulfidation process
Carry out the procedure given in annex B on all the cleaned test pieces (see 9.1.1).
9.1.3 Steam ageing the surface
Carry out the steam ageing procedure given in IEC 60068-2-20:2008, clause 4.1.1, ageing 1b, for a period of
4 h on all the cleaned test pieces (see 9.1.1).
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oSIST prEN ISO 9455-16:2011
ISO/DIS 9455-16
9.1.4 Damp heat, steady state ageing
Subject all the cleaned pieces (see 9.1.1) to the test chamber conditions specified in IEC 60068-2-78:2001,
clause 4, for a period selected from 1 h, 4 h or 24 h.
9.2 Test method
9.2.1 Carry out the following test procedure on each of the ten test pieces. Complete all ten tests within 45
min of the preparation stage (see 9.1).
9.2.2 If the flux under test is of type 1 or type 2 (as defined in ISO 9454-1), maintain the temperature of the
solder bath, see 7.2.
NOTE When testing fluxes which are not type 1 or type 2 (as defined in ISO 9454-1), the bath temperature
requirements and the standard flux to be used for comparison (see clause 8) should be agreed between the purchaser
and the supplier.
9.2.3 Remove one of the test pieces from the acetone, dry it between two sheets of acid-free filter paper
(7.3) and place it in the wetting balance specimen clip, so that the long edges are vertical. Dip the test piece in
the flux solution under test at room temperature, to a depth of no less than 3 mm greater than the selected
depth for immersion of the test piece in the solder (see 9.2.5). Avoid excess flux by withdrawing the test piece
cornerwise from the flux. If excess flux is still visible, touch the corner of the test piece on clean filter paper.
9.2.4 Attach the specimen clip to the wetting balance ensuring that the bottom edge of the test piece is
horizontal and approximately 20 mm above the solder bath (7.2). Allow it to remain there for (20 ± 5) s, so that
the solvent in the flux may evaporate before the test commences (see note). During this drying period, adjust
the suspension force signal and recorder trace to the desired zero position.
NOTE Some types of flux may require a shorter, or a longer, drying time than (20 ± 5) s. In these cases, the drying
time should be agreed between the flux supplier and the user.
Immediately before starting the test, scrape the surface of the solder bath with a blade of suitable material to
remove oxides.
9.2.5 By either raising the solder bath, or lowering the test piece, dip the test piece into the molten solder at
a speed of (20 ± 5) mm/s to a selected depth of either 3 mm ± 0,2 mm or 4 mm ± 0,2 mm.
Hold the test piece in this position for 5 s to 10 s and then withdraw it at a speed of (20 ± 5) mm/s. Record the
wetting force against time for the period during which the test piece is in contact with the solder.
9.2.6 Repeat operations 9.2.2 to 9.2.5 for each of the remaining nine test pieces.
10 Reference value using standard flux
Carry out the procedure described in clause 9, using a further ten test pieces (see clause 8), and using a
standard flux instead of the sample flux under test. If the flux under test is of type 1 or type 2, the standard flux
prepared as described in annex A may be used. If the flux under test is of type 1.1.1 or 1.2.1, use the standard
flux prepared as described in A.5.1. If the flux under test is of type 1.1.2, 1.1.3, 1.2.2 or 1.2.3, use the
standard flux prepared as described in A.5.2.
If the flux under test is not of type 1 or type 2, use a standard flux agreed upon by the purchaser and supplier.
(See the note to 9.2.2.)
11 Presentation of results
A typical trace of wetting force against time is given in figure 1.
4 © ISO 2011 – All rights reserved

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oSIST prEN ISO 9455-16:2011
ISO/DIS 9455-16
In figure 1 non-wetting (upward) forces are shown as negative and wetting (downward) forces are positive.

Key
F Force
T Time
a
 Sample buoyancy line
b
Wetting reference line
Figure 1 — Recorded trace for wetting balance method showing significant points
The following are the points of significance in figure 1.
⎯ Time t is the time at which the test piece first makes contact with the surface of the liquid solder in the
0
bath. It is indicated by a sharp deviation of the recorder trace from the zero force line.
⎯ Time t is the moment at which the solder starts to wet the test piece and corresponds to point A at which
1
the trace begins to fall.
⎯ Time t , corresponding to point B, is the moment at which the recorded force is equal to the upward force
2
due to buoyancy. The position of the sample buoyancy line is calculated from the density of the solder
and the depth of immersion of the test piece as follows.
Force at point B, in mN = ρ x d x a x 9,81 /1000
where
d is the depth of immersion, in millimetres, of the test piece below the undisturbed solder level;
a is the cross sectional area, in square millimetres, of the test piece at the solder line;
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oSIST prEN ISO 9455-16:2011
ISO/DIS 9455-16
ρ is the density in g/ml of solder under test at the test temperature.
⎯ Time t is the time at which the trace crosses the reference line. The line is drawn at a distance
3
corresponding to a force, F, depending on the test piece thickness and the immersion depth as given in
table 1.
Table 1 — Force dependence on test piece thickness and depth of immersion
Thickness Immersion depth Force F
mm mm mN
0,1 3 5,23
0,3 3 5,01
0,1 4 5,17
0,3 4 4,85
NOTE The force F is equal to 2/3 of the theoretical maximum
wetting force on the testpiece assuming a wetting angle of zero
and a liquid-vapour surface tension of 0,4 mN/mm.

⎯ Point C corresponds to the maximum value of the wetting force attained during the specified immersion
period.
⎯ Point D corresponds to the end of the specified immersion period.
12 Expression of results
Carry out the following operations.
12.1 For each of the ten recorded traces obtained for the sample flux, draw the sample buoyancy line
through point B (see clause 11) and draw the wetting reference line 5,6 mN below the buoyancy line (see
figure 1). Read off from each of the traces the time, in seconds:
a) between t and t (i.e. the time to start of wetting);
0 1
b) between t and t (i.e. the time to reach 5,6 mN wetting force). Calculate the mean values for a) and b)
0 3
obtained from the ten traces.
c) Measure the force corresponding to point C (i.e. the maximum wetting force) for each trace. Calculate the
mean value for the maximum wetting force.
12.2 Repeat the operations and calculations described in 12.1 for the ten recorder traces obtained from a
standard flux, in order to obtain the mean values for a), b) and c) for a standard flux.
Compare the mean results for 12.1 a), b) and c) obtained for the sample flux under test with those obtained
from the ten results using the standard flux.
Hence assess the efficacy of the sample flux as:
better than,
as good as,
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oSIST prEN ISO 9455-16:2011
ISO/DIS 9455-16
worse than
the standard flux, in relation to the speed and strength of wetting.
13 Test report
The test report shall include the following information:
a) the identification of the test sample including copper test specification, identification number and flux
identifiers;
b) the test method used (reference to this part of ISO 9455, i.e. ISO 9455-16);
c) the test piece dimensions;
d) the ageing treatment (see 9.1.2 to 9.1.4);
e) the depth of immersion of the test piece in the molten solder (see 9.2.5);
f) details of the standard flux used for comparison;
g) the results obtained;
h) any unusual features noted during the procedure;
i) details of any operation not specified in the method, or any optional operation which may have influenced
the results;
j) nominal temperature and actual temperature range recorded during the test.
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oSIST prEN ISO 9455-16:2011
ISO/DIS 9455-16
Annex A
(normative)

...

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