SIST EN ISO 8401:1999
(Main)Metallic coatings - Review of methods of measurement of ductility (ISO 8401:1986)
Metallic coatings - Review of methods of measurement of ductility (ISO 8401:1986)
Applies to coatings of thickness below 200 /um prepared by electroplating, autocatalytic deposition or other processes. The methods of mearuring the ductility can be divided into test on unsupported foils (the foils may consist of one or more metallic layers) and tests of coatings on substrates (with determining the exact point of crack initation of the top layers).
Metallische Schutzschichten - Überblick über Verfahren zur Messung der Duktilität (ISO 8401:1986)
Diese Internationale Norm legt allgemeine Verfahren zur Messung der Duktilität von metallischen Überzügen mit einer Dicke kleiner als 200 microm fest, die durch elektrolytische Abscheidung, autokatalytische Abscheidung oder andere Verfahren aufgebracht wurden (siehe Anmerkung).
Revetements métalliques - Vue d'ensemble sur les méthodes de mesurage de la ductilité (ISO 8401:1986)
1.1 La présente Norme internationale spécifie un certain nombre de méthodes de mesurage de la ductilité de revêtements métalliques de moins de 200 µm d'épaisseur obtenus par déposition électrolytique, déposition autocatalytique ou autre procédé utilisable (voir la note). Les méthodes de mesurage de la ductilité des revêtements métalliques peuvent se ranger en deux grandes catégories :
les mesurages sur feuilles détachées de leur substrat;
les mesurages sur feuilles avec leur substrat.
NOTE -- Toute méthode d'essai particulière figurant dans les Normes internationales de revêtement doit être utilisée de préférence aux méthodes décrites dans la présente Norme internationale et doit faire l'objet d'un accord préalable entre le fournisseur et le client.
1.2 Dans les mesurages sur feuilles détachées de leur substrat (voir figure 1), les feuilles pouvant être constituées d’une ou plusieurs couches métalliques, il est possible de mesurer la ductilité de la feuille composite et de déterminer l’influence des diverses couches dans la ductilité totale. Les méthodes de mesurage des feuilles détachées de leur substrat sont décrites dans le chapitre 3. Les méthodes de fabrication des feuilles sont étudiées dans l’annexe A.
1.3 Dans les mesurages sur feuilles avec leur substrat (voir figure 2), le plus grand soin doit être apporté à déterminer le point exact d’amorce de fissuration de la couche supérieure.
Différentes méthodes sont utilisables à cet effet, soit a l’oeil nu ou corrigé, soit à l’aide d’une loupe. Ces méthodes peuvent également servir à détecter une fragilisation du substrat qui
peut résulter du mode de revêtement. Les méthodes de mesurage des feuilles sur leur substrat sont décrites dans le chapitre 4.
1.4 Bien que la ductilité soit une propriété du matériau n’ayant rien à voir avec les dimensions des éprouvettes, l ’épaisseur du revêtement peut avoir une influence sur la valeur de l’allongement linéaire (Al/lo).
1.4.1 Les couches trés minces ont des propriétés différentes car le substrat a une influence sur la superposition des premières couches (épitaxie). Ces couches peuvent être le siége de contraintes internes élevées qui peuvent jouer sur la ductilité.
1.4.2 Il est essentiel q ue l’éprouvette ait une épaisseur uniforme, les endroits plus mi nces pouvan t favoriser une fissuration précoce. De même, la densité de courant est plus faible aux endroits minces et plus forte aux endroits épais des éprouvettes à dépôt électrolytique. Ces différences de densité de courant peuvent ainsi donner lieu à des différences de ductilité. La densité de courant doit donc être maintenue aussi uniforme que possible sur toute l’éprouvette et la valeur correspondante doit être notée.
Kovinske prevleke - Pregled postopkov merjenja duktilnosti (ISO 8401:1986)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 8401:1999
01-oktober-1999
Kovinske prevleke - Pregled postopkov merjenja duktilnosti (ISO 8401:1986)
Metallic coatings - Review of methods of measurement of ductility (ISO 8401:1986)
Metallische Schutzschichten - Überblick über Verfahren zur Messung der Duktilität (ISO
8401:1986)
Revetements métalliques - Vue d'ensemble sur les méthodes de mesurage de la ductilité
(ISO 8401:1986)
Ta slovenski standard je istoveten z: EN ISO 8401:1994
ICS:
25.220.40 Kovinske prevleke Metallic coatings
SIST EN ISO 8401:1999 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
SIST EN ISO 8401:1999
---------------------- Page: 2 ----------------------
SIST EN ISO 8401:1999
---------------------- Page: 3 ----------------------
SIST EN ISO 8401:1999
---------------------- Page: 4 ----------------------
SIST EN ISO 8401:1999
INTERNATIONAL ORGANIZATION FOR STANDARDOZATIONWVIEX~YHAPOP~HAR OPBAHl43AiJMR !-IO CTAHAAPTM3ALlMM@ORGANISATION INTERNATIONALE DE NORMALISATION
e CC S
Vue d’ensemble swr les mkthodes de mesurage de Ia ductilte
Revhemen ts rne talliques -
First edition - 1986-0745
DC 621.793 : 620.1 : 539.52 Ref.
0. ISO i-l986 (EI
Descriptots : coatings, metal coatings, tests, mechanical tests, ductility tests, ductility.
Price based on 31 pages
---------------------- Page: 5 ----------------------
SIST EN ISO 8401:1999
orewor
BS0 (the lnternational Organkation for Standardization) is a worldwide federation of
national Standards bodies (ISO member bedies). The work of preparing lnternational
Standards is normally carried out through BS0 technical committees. Esch member
body interested in a subject for which a technical committee has been established has
the right to be represented on that committee. lnternational organizations, govern-
mental and non-governmental, in liaison with ISO, also take part in the work.
Draft International Standards adopted by the technical committees are circulated to
the member bodies for approval before their acceptance as International Standards by
the ISO Council. They are approved in accordance with ISO procedures requiring at
least 75 % approval by the member bodies voting.
International Standard ISO 8401 was prepared by Technical Committee ISO/TC 107,
Metallic and o ther non-organic cos tings.
Users should note that all International Standards undergo revision from time to time
and that any reference made herein to any other International Standard implies its
latest edition, unless otherwise stated.
0 International Organkation for Standardkation, 1986
Printed in Switzerland
ii
---------------------- Page: 6 ----------------------
SIST EN ISO 8401:1999
ts
Page
.......................................... 1
1 Scope and field of application
1
efinitions .
............................................. 1
3 Tests On unsupported foils
.................................................. 2
3.1 Tensile testing
................................... 2
3.2 Bending (micrometer bend test)
.......................................... 3
3.3 Folding (vice-bend test)
................................................ 3
3. Hydraulic bulging
.............................................. 4
3.5 echanical bulging
........................................ 4
4 Tests on coatings on substrates
5
4.1 Tensiletesting .
......................................... 5
4.2 Three-Point bend testing
.......................................... 5
.3 Four-point bend testing
....................................... 6
4.4 Cylindrical mandrei bending
........................................... 6
4.5 Spiral mandrei bending
......................................... 6
4.6 Conical mandrel bending
6
..............................................
4.7 Mechanical bulging
7
5 Selection of test method .
7
-best report .
Annexes
8
Methods of producing foils .
A
Calculation of ductility when increasing the surface area of a foil (bulging). . 9
B
10
Calculation of ductility and tensile strength in the hydraulic bulge test .
C
....................... 11
D Calculation of ductility in the mechanical bulge test
.......................................................... 31
. . .
Ill
---------------------- Page: 7 ----------------------
SIST EN ISO 8401:1999
---------------------- Page: 8 ----------------------
SIST EN ISO 8401:1999
current density is bwer at thinner parts and higher at thicker
parts cf electrsplated test pieces; in this way current density
ifferences may res t in different ductilities.
current
This Bnternatianal Standard spedies general meths
ensity applied snou be maintained as unifor possible
below
measuring the ductility sf metalk coatings cf thickness
its value reported.
over the test piece,
200 Pm prepared by electrsplating, autocatalytic deposition cr
other processes (sec the note).
of meaallic coatings tan
The methods cf measuring the ductilit
itions
be divided into two main cate
Fm- the purpose cf tnis International Standard, the follo
- tests on unsupporte
strate);
-
tests cf coatings on su
r~cfilify : Tne ability of a metallic cr other coating to
undergo plastic cr elastic deformation, or both, withou% frac-
NOTE - When specific methods od testing are included in lnter-
ture or cracking.
national Standards for individual coatings, tkey should be used in
preference to the methods describe nationa! Standard and
should be agreed upon beforehand ier and the purchaser.
ratio sf the elongation, AI, to a
e test piece. Chis is taken as a
1.2 In the testin
Substrate (see figure 11, Pne foils may cansist cf one or more
metallic layers. Therefore it BS possible ts measure the ductility
f%en this ratio is expresse
the influence sf in
s of testing of unsu
foils are descr thsds cf prsducing
ormaily the %es% pieces are elsngated. With some bending
tests, the outer layer of the test piece, i.e. the pllating, is
.3 In the testing cf cdating
elsngated (sec figure 3). In bulge tests, however, the surface sf
dete
specially important to
d, requiring calculation of linear elongation
initiation cf the top layer.
n in the thickness. Using the component sf
methods sf discerning this point, by normal cr ccrrected-%o-
ching) in only one axis would give false infor-
normal visisn cr with a lens. See t uidance in the individual
ductility sf the material (sec figure 4). In
methods. These methsds ca
tnsse cases the thinning of the foil, as calculated from the
ate tnat may have resulted f
increase in %he surface area a better measure of the ductility
of %esting sf coatings on su
cf the material (see annex
.
kness 0% %he
%es% piece,
rted foils
e value cf I r elongatisn
ese techniques invslve measurement cf a feil which has been
separated from the Substrate (sec figure 11. In this case, the foil
erties as the buil
to be tes%ed tan also consist cf several layers so as to allow
e influence of undercoats on the ductility of
Examples are gsld flash on goldkapper
Bated nicke1 deposits. Methods sf pro-
d fsils are given in annex A.
-2 lt is essential tha% t e %est piece has unifor
as thinner spots will give rise to premature cracking. Also, the
---------------------- Page: 9 ----------------------
SIST EN ISO 8401:1999
termination of e linear elongation of a d iS
hg ma
Pe
stressing the feil is lengthened, t both he
Coefficient cf Variation
ickness of the fsil diminish.
echanicajiy prepared test pieces tan have csefficients of
-
Variation, SID (where s is the stan ard deviatisn and D the
s methsd may
available
ntr
Babsratories. Ul ßsr some applic
er coefficients sf Variation.
ment adapted ts microscopic inspectisn during the test may
used.
Preparatisn 0% test pieces
Necking sf the test piece (sec figure 8) may require
ent of very small changes in length and the use of a
test pieces ints %he jaws of a
kable resist by sik screen
printing cr by applying a photosensitive resist. These fast
are ball be Paken to avoid twistin
methods are widely used in the printed circuit industry. The test
ieces are usually rectangular in shape, but tan be widened a%
0th ends ts avoid breaking in the clamping jaws (sec fig
3.1.6.4 When th scurces cf error (3.1.6.1 to 3.1.6.3)
methods sf preparing the test pieces may Cause
other methods of measuring ductility
tan
racking at the edges that results in premature failure and
sh0
results. Test piece preparation involving photoprinting
or electroforming is preferred ts avoid edge defects.
Test pieces plated into the final’for
unless shielding and other techniques are used to ensure
2.1 eneral
uniform current distributisn (sec figure IO).
This method is suita Ie only for the evaluation of me%allic foik
ake equidistant marks on the surface of the tesf piece as
having low ductility. [Zl The values obtained have no simple
ilbustrated in figure 7. Determine the distance between the
relation to values obtained by other methods. This method is
marks before testing.
useful for brittle metak such as bright nickel.
Procedure 3.2.2 Apparatus
cf the tensi
lamp the test piece between the jaws icrometer.
ment and apply strain using a
u% Strips sf 0,s cm x 7,s cm from the feil under test. The foik
are usually 25 to 40 prn thick. The difficulties described in 3.1.3
and 3.1.6 apply likewise to this test. easure the thickness sf
the tes% piece at the Point cf bending, using an instrument cr
.5.1 Calculation methsd which enables the thickness to be determined to within
5 5% of i%s nominal vallue.
The ductility, Pa, ex ressed as a percentage, is
equation
rocedur
-shape and place it between the
jaws sf the microme%er so that as the jaws are clssed the bend
---------------------- Page: 10 ----------------------
SIST EN ISO 8401:1999
.3.3 reparation sf test pieces
remains between the jaws Glose the micrometer jaws slowly
until the foil cracks.
Cut rectangular Strips, 1 cm wide by 5 cm lang, from the
foiS.
Wecord the micrometer readin and the tMmess of the fQi1
(sec figure 11).
Carry out the test at least in duplicate.
Grip the test piece between the jaws of the vice. Bend the test
32.5 Expression od results through 90°, then bend it successively in opposite
h 180” until fracture occurs.
3.2.5.1 Calculation
esults
Calculate the average of the micrometer readings (sec 32.4).
ends is taken as a measure of ductility.
The ductility, D, expressed as a percentage, is given by the
equation (sec figure 12)
6
DZ----
x 100
Zr- 6
.l enera
where
raulic bulge-testing tan be used to measure the ductility of
sheet materials accurately. lQo machining of the test piece
6 is the thickness sf the test pieces;
is required, there are no problems of achieving axial alignment
as in tensile testing, and the test is especially useful for measur-
2F is the average sf the micrometer readings.
uctility of ductile materials. Until recently, the lack of
commercially available equipment has prevented wider use of
3.2.5.2 Precision
this method. 131
As the value of D rises more rapidly than 6, it is essential that
3.42 Principle (sec figure 14)
the value of 6 be measured with high precision. lf a foil of
20 ym is read as 25 Pm, the following differente, supposing
Clamping sf a test piece between a bottom cylinder and an
27 = 0,5 cm, will be found :
er platen has a circular opening of the
cylinder. lncreasing the
20 x IO-4
x 100 = 0,4 ?h
slowly and steadily to deform the test piece i
D1= Q5-
20 x m-4
I
dome until the feil bursts.
25 x 10-4
D2 = x 1 = 0,5 %
0,5 - 25 x m-4
See figure 15,
i.e. a differente sf O,5 - O,4 = O,I %.
A thickness of 25 Fm will give resuks that are 25 % higher t
3.44 Procedure
Bor a 20 Pm thickness.
ally in figure 15, fill the
the equipment shown sc
at this method will give reproducible results only
m cylinder with water to Place the test piece on
when 6 is measured to within 1 Pm and 2r to within O,OI cm.
the surface sf the water. Use the upper platen, in the shape of a
hollow cone, to clamp the test piece firmly in
Fill the hollow cone with
ater from the reservoir that is pro-
vided. The excess water will rise in the glass gauge. When the
level of the water is above the light-sensing device, close the
3.3.1 General
valve that controls the flow of water from the reservoir
the motor on and slowly raise the light-sensing device.
Although this test is simple and may have some utility, the
the device is aligned with the meniscus, the beam o
nature of the test, the cold working that occurs as a result of
within the device will be deflected; the drop in voltage that
bending, and othet factors may lead to incorrect measures of
occurs as a result of this shuts off the motor.
ductility. The thickness sf the test piece affects the results, but
the influence of thickness cannot be calculated.
The pres under the test piece is increased by means of the
plunger. en the meniscus in the glass gauge begins to rise,
the motor will automatically begin to operate and the light-
3.3.2 Apparatus
sensing device will track the rise in the level of water. By means
sf the potentiometer, record the increase in volume on an X-V
Machinist’s
vice, equipped with two small machined jaws to
recorder.
hold the test piece (see figure 13).
3
---------------------- Page: 11 ----------------------
SIST EN ISO 8401:1999
.5.3 Procedure
pressure Sensor in the cylinder simultaneously records the
pressure beneath the test piece. In a commercial version o
een the circular plates. Clamp the
is used to shut the
equipment, a pressure-sensitive switch
ates together firmly by means of two screws.
motor off at the moment of burstin SQ that the total volume of
Then slswly push the test piece upward by turning the micro-
displaced water tan be read directl hm the digital display on
Wead from the micromet e distance travelled by the
the Potentiometer.
the metaB film to the psiritt
of Crack initiation.
Expression of results
.5
e initial contact Point between the steel ball and the
piece is detected electrically. A battery-operated lamp is fi
JL5.1 Calculation
into the upper brass plate in such a way that the lamp lights at
the instant the steel ball touches the test piece. The lamp stays
The ductility of the metal specimen may be calculated from the
lit throughout the test.
volume of the displaced water, which equals the volume inside
the dome. The ductility, expressed as a percentage, is given by
The visual detection of the initiation of rupture is accomplished
the equation derived and discussed in annex C. The tensile
with the aid of a magnifier (X 15) attached to the upper plate
strength of the metal foil may also be determined from the
(but not shown in figure 17).
alue of the pressure at bursting (sec annex CL
3.5.4 Expression of results
3.4.5.2 Coefficient of Variation
It is possible to calculate the ductility from the height sf the
cone by calculating the loss sf thickness sf the foil Esee
ecause only the centre of the foil (@ 3 cm) is tested, the
annex DB.
current density and the thickness in this region are probably
more constant than in the case of tensile tests. Values of
-
slD = Q,O5, i.e. 5 %, are easily arrived at.
3.5.5 Special cases
lt may be preferable to use a slightly altered procedure. In the
.4.6 Notes on prscedure
apparatus shown schematically in figures 18, 19 and 20, the
steel ball remains stationary, but the two plates and the Sample
Pinholes in the test piece are one possible Source of error.
are moved downward with a motor until the test piece Cracks.
Pinholes tan be detected Prior to testing by “candling”. A
IO0 W light bulb in a box with a hole slightly smaller in diameter
The instrument is placed under a microscope which enables
than the opening in the top plate or cone is satisfactory.
use of X 70 magnification when looking for the first Cracks. At
the Start of the Pest, the motor Stops when electrical contact
pinholes are present, it is possible to underlay the test
between the steel ball and the test piece is made. At the
with a very thin plastic foil which will stop the water from
moment sf cracking the motor is stopped by hand. The height
passing through the pinholes.
of the cone is measured by the displacement of a linear poten-
tiometer with a resolution of 5 um.
By visual Observation it is possible to note the moment of
cracking.
With the motor-driven apparatus, it is easier to obtain good
results because
Stopping the motor of the light-sensin g device at this moment
he ductility sf the porous feil.
will give fair indication of t
a) there is no twisting moment of the steel ball against the
feil, which will be the case when turning the micrometer
screw;
3.5 echanical buBging
b) a microscope, preferably with interference lighting of
the Nomarski-type, will indicate the moment of appearance
sf the first Cracks with more reliability;
3.5.1 General
c) electrical measu rement sf the height of the cone is
echanical bulge tests are similar to hydraulic bulge tests. The
more precise than a icrometer;
dome, however, is formed mechanically cos indicated sche-
matically in figure 16. d) better lighting and the fact that the distance between
the microscope and the summit of the cone is constant give
more reproducible data than in the case of the micrometer
-
.5.2 Apparatus
instrument. A value of s/D = O,O5, i.e. 5 %, is easily
arrived at.
Equipment for measuring the ductility sf thin
metal foils is no%
readily available, but tan be easily assem
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.