prEN 12797
(Main)Brazing - Destructive tests of brazed joints
Brazing - Destructive tests of brazed joints
This European Standard describes destructive test procedures and test piece types necessary to perform the tests on brazed joints.
Brazed joints are used in a wide variety of assemblies and the design requirements placed upon these joints will also vary widely; there will usually be some level of strength required but this may not be explicitly stated and is frequently of minor importance compared to some other criterion, e.g. hermeticity. It follows that a test which measures strength may be totally irrelevant in assessing a joint for a particular application where strength is a minor consideration. This situation is made more complicated because brazed joints are almost invariably designed to be loaded in shear and the dimensions of the joint affect the shear strength to a much greater extent than they do the tensile strength. The tests described in this standard have been used successfully to give information on specific properties and where such information is needed, it is recommended that one of them be specified.
It is vital to recognise that for many fabrications none of these tests will be suitable and specific tests will have to be devised, which do yield the requisite information (which may be qualitative rather than quantitative). The destructive test methods described are as follows:
a) shear tests (see Clause 4);
b) tensile tests (see Clause 5);
c) metallographic examination (see Clause 6);
d) hardness tests (see Clause 7);
e) peel test (see Clause 8);
f) bend tests (see Clause 9).
Details of burst tests are not included as these are not commonly used on brazed joints.
The type of test piece described for each test can be quoted or incorporated in engineering applications standards that deal with brazed assemblies.
The results of the tests are used:
g) to determine basic data regarding filler metal performance;
h) to arrive at optimum brazing designs (including gaps) and brazing procedures;
i) to relate production results to results achieved in development.
This European Standard does not recommend the number of samples to be tested or the repeat tests allowed. Neither does it specify methods of sampling brazed joints, except to give guidance regarding the precautions necessary, nor does it comment on the acceptance criteria applicable to any of the tests.
No attempt is made to define which test or tests, if any, should be applied in any situation. This is a matter to be established before any particular method of test is selected.
Hartlöten - Zerstörende Prüfung von Hartlötverbindungen
Diese Europäische Norm beschreibt zerstörende Prüfverfahren und Arten von Prüfstücken, die zur Durchführung von Prüfungen an Hartlötverbindungen notwendig sind.
Hartlötverbindungen werden in einer Vielzahl von Baugruppen genutzt und die konstruktiven Anforderungen, die an diese Verbindungen gestellt werden, sind ebenfalls sehr unterschiedlich; normalerweise wird eine bestimmte Festigkeit gefordert; das wird jedoch möglicherweise nicht ausdrücklich angegeben und ist häufig im Vergleich zu anderen Kriterien, z. B. Luftdichtheit, von geringerer Bedeutung. Daraus folgt, dass eine Festigkeitsprüfung für die Beurteilung einer Verbindung für eine besondere Anwendung vollständig belanglos sein kann, wenn die Festigkeit von geringerer Bedeutung ist. Diese Situation wird dadurch erschwert, dass Hartlötverbindungen nahezu ausnahmslos dafür ausgelegt sind, auf Scherung beansprucht zu werden, und die Abmessungen der Verbindung die Scherfestigkeit in viel größerem Umfang beeinflussen als die Zugfestigkeit. Die in dieser Norm beschriebenen Prüfverfahren sind erfolgreich angewendet worden, um Informationen über spezifische Eigenschaften zu erhalten; es wird empfohlen, eines von ihnen festzulegen, wenn derartige Informationen benötigt werden.
Wesentlich ist die Erkenntnis, dass für viele Fertigungen keine dieser Prüfungen geeignet ist und daher spezifische Prüfungen zu entwickeln sind, um die notwendigen Informationen zu erhalten (die eher qualitativ als quantitativ sein können). Die folgenden zerstörenden Prüfverfahren werden beschrieben:
a) Scherzugprüfungen (siehe Abschnitt 4);
b) Zugprüfungen (siehe Abschnitt 5);
c) Metallographische Untersuchung (siehe Abschnitt 6);
d) Härteprüfungen (siehe Abschnitt 7);
e) Schälprüfung (siehe Abschnitt 8);
f) Biegeprüfungen (siehe Abschnitt 9).
Da Berstprüfungen bei Hartlötverbindungen nicht allgemein gebräuchlich sind, sind Einzelheiten darüber nicht enthalten.
Die Art des Prüfstücks, das für jede Prüfung beschrieben wird, kann angeführt oder in die technischen Anwendungsnormen, die hartgelötete Baugruppen behandeln, aufgenommen werden.
Die Ergebnisse der Prüfungen werden genutzt, um:
g) Basisdaten bezüglich des Verhaltens des Lots zu ermitteln;
h) optimale Hartlötkonstruktionen (einschließlich Hartlötspalten) und Hartlötverfahren zu erstellen;
i) die Fertigungsergebnisse mit den Ergebnissen, die bei der Entwicklung erzielt wurden, in Beziehung zu setzen.
Diese Europäische Norm empfiehlt nicht die Anzahl der zu untersuchenden Proben oder der zulässigen Wiederholungsprüfungen. Sie legt bis auf einen aufgeführten Leitfaden bezüglich der notwendigen Vorsichtsmaßnahmen weder die Verfahren der Probenahme aus den Hartlötverbindungen fest, noch erläutert sie die Bewertungsmerkmale, die für jede der Prüfungen gelten.
Es wurde nicht versucht festzulegen, welche Prüfung bzw. Prüfungen in welcher Situation angewendet werden sollte(n). Dies ist zu vereinbaren, bevor ein spezielles Prüfverfahren ausgewählt wird.
Brasage fort - Essais destructifs des assemblages réalisés par brasage fort
La présente norme européenne décrit des procédures d'essais destructifs et des types de pièce d'essai nécessaires pour effectuer les essais sur assemblages réalisés par brasage fort (assemblages brasés).
Les assemblages brasés sont utilisés pour une grande variété d'assemblages et les exigences de conception dont font l'objet ces assemblages brasés sont très diverses ; en général, un certain niveau de résistance est exigé, mais celui-ci peut ne pas être mentionné explicitement et il revêt souvent une moindre importance en comparaison avec d'autres critères tels que l'étanchéité. Il s'ensuit qu'un essai consistant à mesurer la résistance peut être complètement inadéquat pour évaluer un assemblage brasé pour une application particulière où la résistance a une moindre importance. La situation est rendue plus complexe car les assemblages brasés sont presque systématiquement conçus pour des charges de cisaillement et les dimensions de l'assemblage brasé affectent la résistance au cisaillement dans une bien plus grande mesure qu'ils n'affectent la résistance à la traction. Les essais décrits dans la présente norme européenne ont permis d'obtenir des informations sur des propriétés spécifiques, et lorsque de telles informations sont nécessaires, il est recommandé que l'un de ces essais soit spécifié.
Il faut admettre que pour de nombreuses fabrications brasées, aucun de ces essais ne convient et des essais spécifiques appropriés, permettant d'obtenir les informations recherchées, doivent être conçus (ils peuvent être qualitatifs plutôt que quantitatifs). Les méthodes d'essai destructif décrites sont les suivantes :
a) essai de cisaillement (voir article 4) ;
b) essai de traction (voir article 5) ;
c) examen métallographique (voir article 6) ;
d) essai de dureté (voir article 7) ;
e) essai de pelage (voir article 8) ;
f) essai de pliage (voir article 9).
Les essais d'éclatement ne font pas partie des méthodes décrites en détail, étant donné qu'ils ne sont pas couramment utilisés pour les assemblages brasés.
Le type de pièce d'essai décrit pour chaque essai peut être cité ou incorporé dans les normes d'applications techniques qui portent sur les assemblages brasés.
Les résultats des essais sont utilisés :
g) afin de déterminer les résultats essentiels concernant les performances du métal d'apport de brasage fort ;
h) afin de parvenir à une conception optimale des assemblages brasés (y compris des jeux) et à des modes opératoires de brasage optimums ;
i) afin de mettre en relation les résultats obtenus en production avec ceux obtenus en développement.
La présente norme européenne ne donne pas de recommandations concernant le nombre d'échantillons à sou- mettre aux essais ou concernant les contre-essais autorisés. Elle ne spécifie pas de méthodes d'échantillonnage des assemblages brasés, bien qu'elle donne des précisions sur les précautions à prendre à ce sujet, et ne formule pas de commentaires sur les critères d'acceptation applicables aux essais.
Cette norme n'a pas pour objet de définir les essais qu'il convient d'effectuer en fonction des situations particulières. Ce point doit être établi avant la sélection d’une méthode d’essai particulière.
Trdo spajkanje - Porušitveno preskušanje trdo spajkanih spojev
General Information
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Standards Content (Sample)
SLOVENSKI STANDARD
01-september-2017
Trdo spajkanje - Porušitveno preskušanje trdo spajkanih spojev
Brazing - Destructive tests of brazed joints
Hartlöten - Zerstörende Prüfung von Hartlötverbindungen
Brasage fort - Essais destructifs des assemblages réalisés par brasage fort
Ta slovenski standard je istoveten z: prEN 12797
ICS:
25.160.50 Trdo in mehko lotanje Brazing and soldering
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2017
ICS 25.160.50 Will supersede EN 12797:2000
English Version
Brazing - Destructive tests of brazed joints
Brasage fort - Essais destructifs des assemblages Hartlöten - Zerstörende Prüfung von
réalisés par brasage fort Hartlötverbindungen
This draft European Standard is submitted to CEN members for 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey 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
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 12797:2017 E
worldwide for CEN national Members.
Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 5
3 General principles . 5
4 Shear tests . 6
4.1 General . 6
4.2 Principle . 6
4.3 Test pieces and specimens . 6
4.4 Procedure. 6
4.5 Test results and information to be reported. 7
5 Tensile tests . 9
5.1 General . 9
5.2 Principle . 10
5.3 Test pieces and specimens . 10
5.4 Procedure. 10
5.5 Test results and information to be reported. 14
6 Metallographic examination . 15
6.1 General . 15
6.2 Principle . 15
6.3 Preparation of the test specimen . 15
6.4 Procedure. 15
6.5 Test results and information to be reported. 16
7 Hardness testing . 16
7.1 General . 16
7.2 Principle . 16
7.3 Preparation of the test specimen . 16
7.4 Procedure. 17
7.4.1 Macro-hardness test . 17
7.4.2 Low-force hardness test. 17
7.4.3 Micro-hardness test. 17
7.5 Test results and information to be reported. 17
8 Peel tests . 18
8.1 General . 18
8.2 Principle . 18
8.3 Preparation of the test specimen . 18
8.4 Procedure. 18
8.5 Test results and information to be reported. 19
9 Bend tests . 19
9.1 General . 19
9.2 Principle . 20
9.3 Preparation of the test specimen . 20
9.4 Procedure. 20
9.5 Test results and information to be reported. 20
Annex A (informative) Imperfections in brazed joints . 25
European foreword
This document (prEN 12797:2017) has been prepared by Technical Committee CEN/TC 121 “Welding
and allied processes”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 12797:2000.
In comparison with the previous edition, the main changes are:
a) the normative references have been updated;
b) the document has been revised editorially.
1 Scope
This European Standard describes destructive test procedures and test piece types necessary to
perform the tests on brazed joints.
Brazed joints are used in a wide variety of assemblies and the design requirements placed upon these
joints will also vary widely; there will usually be some level of strength required but this may not be
explicitly stated and is frequently of minor importance compared to some other criterion, e.g.
hermeticity. It follows that a test which measures strength may be totally irrelevant in assessing a joint
for a particular application where strength is a minor consideration. This situation is made more
complicated because brazed joints are almost invariably designed to be loaded in shear and the
dimensions of the joint affect the shear strength to a much greater extent than they do the tensile
strength. The tests described in this standard have been used successfully to give information on
specific properties and where such information is needed, it is recommended that one of them be
specified.
It is vital to recognise that for many fabrications none of these tests will be suitable and specific tests
will have to be devised, which do yield the requisite information (which may be qualitative rather than
quantitative). The destructive test methods described are as follows:
a) shear tests (see Clause 4);
b) tensile tests (see Clause 5);
c) metallographic examination (see Clause 6);
d) hardness tests (see Clause 7);
e) peel test (see Clause 8);
f) bend tests (see Clause 9).
Details of burst tests are not included as these are not commonly used on brazed joints.
The type of test piece described for each test can be quoted or incorporated in engineering applications
standards that deal with brazed assemblies.
The results of the tests are used:
g) to determine basic data regarding filler metal performance;
h) to arrive at optimum brazing designs (including gaps) and brazing procedures;
i) to relate production results to results achieved in development.
This European Standard does not recommend the number of samples to be tested or the repeat tests
allowed. Neither does it specify methods of sampling brazed joints, except to give guidance regarding
the precautions necessary, nor does it comment on the acceptance criteria applicable to any of the
tests.
No attempt is made to define which test or tests, if any, should be applied in any situation. This is a
matter to be established before any particular method of test is selected.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
EN 12799:2000, Brazing - Non-destructive examination of brazed joints
EN ISO 4545-1, Metallic materials - Knoop hardness test - Part 1: Test method (ISO 4545-1)
EN ISO 5173, Destructive tests on welds in metallic materials - Bend tests (ISO 5173)
EN ISO 6506-1, Metallic materials - Brinell hardness test - Part 1: Test method (ISO 6506-1)
EN ISO 6507-1, Metallic materials - Vickers hardness test - Part 1: Test method (ISO 6507-1)
EN ISO 6508-1, Metallic materials - Rockwell hardness test - Part 1: Test method (ISO 6508-1)
EN ISO 6892-1, Metallic materials - Tensile testing - Part 1: Method of test at room temperature
(ISO 6892-1)
EN ISO 7438, Metallic materials - Bend test (ISO 7438)
ISO 5187, Welding and allied processes - Assemblies made with soft solders and brazing filler metals -
Mechanical test methods
3 General principles
Imperfections may be observed when joints are examined by destructive tests. They may reduce the
quality and performance characteristics of the joint or the brazed assembly.
Destructive tests may be needed to determine the effects of the brazing process or any subsequent heat
treatment on the properties of the joint (e.g. parent materials, filler metals, internal stresses).
This European Standard does not give guidance regardi
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