Note: Descriptions are shown in the official language in which they were submitted.
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METHOD AND APPARATUS FOR PRODUCING STRIP-LIKE
OR FOIL-LIKE PRODUCTS
KIWI VL~I~O~
The present invention relates to methods
and apparatuses, as well as a use of the method
for producing strip-like or foil-like products
from metallic or metallic oxide material, in
which a metallic or metallic oxide melt from
at least one storage container is applied through
at least one nozzle opening to the surface of a
cooler moved at a regulated speed.
A method and an apparatus for producing
amorphous metal strips are known (European Patent
0,026,812), in which a metallic melt from a
storage container is forced out of at least one
nozzle opening and is left to solidify on the
surface of a cooler moved past the nozzle opening
in the immediate vicinity thereof. This is based
on the use of circular nozzles with a diameter of
0.5 to lam and when used for producing amorphous
metal strips, there is an optimum relationship
between the nozzle opening, the distance between
the nozzle opening and the cooler surface and
the speed of the cooler surface. This permits
the production of uniformly formed metal strips
at high production speeds. Such strips can either
be completely amorphous or consist of a two-phase
amorphous/crystalline mixture. The term amorphous
metal alloy is understood to mean an alloy, whose
molecular structure is at least 50% and preferably
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at least 80% amorphous.
In addition, a method and an apparatus
for producing a metal strip are known (German
Patent 2,746,238), which proposes various nozzle
shapes, which are complicated to malefactor,
for the production of "wide" metal strips. The
greatest strip width obtainable is 12mm. Within
the scope of this proposal, it is also pointed out
that it must fundamentally be possible for a
lo plurality of parallel, uniform nozzle jets to
strike a moving substrate from a suitable distance,
e.g. in order to obtain relatively wide strips.
However, this test has led to difficulties,
particularly as the nozzle jets do not combine
to form a pot, so that it is very difficult to
obtain strips with a unfunny cross-section. It is
also difficult, if not impossible, to obtain a
pool with an adequately uniform thickness for
drawing strips with an approximately unifol~n
cross-section wider than about 7.5mm. To overcome
these difficulties, German Patent 2,746,238
proposes devices with stepped nozzle shapes very
close to the cooler surface, which make it
possible to produce strips with more unify-
thicknesses and widths, as well as uniform strength characteristics up to the range of the aforementioned
widths.
In conjunction with an apparatus for
producing metal strips at a high speed, a nozzle
body with a curved surface and a slot-like nozzle
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opening are known for the purpose of influencing
the slow conditions between the nozzle body and
the cooler surface (European Patent 0,040,069~.
The strips produced in this way mainly have an
amorphous structure. The coating of the cooler
surface with referent materials is also described,
but exclusively with respect to obtaining specific
physical surface properties, particularly for the
completely satisfactory and easy detachmellt of
the strips produced from the cooler surface.
Finally, British Patent 2,083,455 discloses a
drum-like cooler, which has a circumferential slot.
The circumferential slot on the drum to a certain
extent serves as a mound for a relatively thick
metal strip, which can subsequently be cut at
right angles to form small disks, as are convent
tonally used in the manufacture of semiconductors.
All the known methods and apparatuses for
producing strips of the aforementioned type suffer
from the important disadvantage that it has not
hitherto been possible in a practical manner to
produce strips significantly wider than about
15cm, despite a very considerable need for such
strips, which could hitherto only be produced by
complicated and cost-intensive rolling processes.
where is also a need for wider strips with an
amorphous structure, which e.g. permit the
production of transformers. Such transfol~ers
have an approximately 30% lower magnetic reversal
losses than conventional stacks of sheets.
I
Furthermore, known methods and apparatuses for pro-
during strips of the aforementioned type are used exclusively
for producing strips with homogeneous structures. No methods or
apparatuses for producing strips are known, which have junta-
posed areas with different metallurgical structures, or
different geometrical structures. This is in spite of the fact
that there is a considerable requirelllent for such strips, e.g.
for packaging foils, which hitherto had to be produced by the
more complicated and cost-intens;ve rolling process, or for
mass-produced products, particularly small parts, from strip or
foil material, which hitherto had to be stamped or punched out
of closed foils or strips. The stamping or punching process is
also of a complicated and costly nature.
SUMMARY OF THE INVENTION
The problem of the present invention is to provide a
method and an apparatus, permitting the production of strips
from metallic or metallic oxide material of any random width and
which also permit the production of strips with separate areas
: of different structures (amorphous or crystalline).
It is also intended to permit the production of strips
or foils with adjacent areas of different metallic andtor go-
metrical structures.
According to the present invention there is provided a
method for producing strip-like or foil-like products from
. metallic or metallic oxide material, a metallic or metallic
I oxide melt from at least one storage container being applied
; through at least one nozzle opening to the surface of a cooler
moved at a regulated speed, wherein melts flowing out of a
plurality of juxtaposed nozzle openings are combined into a
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. closed melt on striking the cooler surface, the melts being made to solidify at the combining instant, in such a way that a
closed material layer of desired width is formed.
; Thus, by partly overcoming
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the hitherto known difficulties and the
prejudices linked therewith, it is possible to
produce strips of virtually a random width and
strips with separate areas of different structures
(amorphous or crystalline), thereby
oaring a wide range of uses. For example, it is
possible to produce a foil having an amorphous
structure in the central area, so that it is rigid
and dimensionally stable, or can be permeable or
impermeable to air as required, whereas in the
edge areas, in which the foil is connected to other
elements, e.g. folded, it has a soft and flexible
crystalline structure By the combined control of
the method parameters for juxtaposed nozzles or
nozzle groups, it is possible to largely determine
in an advantageous manner the material kirk-
teristics of the strips to be produced. Strips
produced according to this method can be used
in a particularly advantageous manner for cladding
or lining mechanically or chemically stressed
parts, e.g. pipelines, in order to make them
corros;on-proof, or friction bearings. When using
strips or foils produced according to the invention,
such articles can be manufactured more simply and
cheaply than when produced by traditional methods.
In addition, the products produced according to
the proposed method have better technological
properties than conventionally produced products,
e.g. by a powder-metallurgical method. According
to another method according to the invention, it is
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possible by segmenting, perforating or profiling
the cooler surface to define geometrically
bounded areas, so that it is possible on the one
hand to produce foils with a structured surface
and on the other those with shape or form-limited
individual areas. Thus it is possible in a
simple and appropriatem~nner to mass produce small
parts from strip or fowl material.
BRIEF DESCRIPTION OF THE DRAWINGS
__ __ PA _ _ __ _ __ _
The invention is described hereinafter
relative to non-limitative embodiments and the
attached drawings, wherein show:
Fig 1 a diagrammatic perspective view of an
apparatus for performing the method.
15 Fig 2 a first embodiment of a nozzle body with
several individual slots.
Fig 3 a second embodiment with a slot nozzle formed
from individual nozzles.
Fig 4 another embodiment with displaced individual
nozzles and separate nozzle bodies.
Fig 5 a top view of the apparatus according to
Fig 4.
Figs pa and 6b, a view from below of a nozzle body
with displaced Nazi slots.
Figs pa to 7c nozzle modules with a through nozzle
slot.
Figs pa to 8c nozzle modules with displaced nozzle
s lots .
Fig pa and 9b nozzle modules with sloping nozzle
30 slots.
~'~ Z 6
Fig 10 the basic view of a complete apparatus
for performing the method.
Fig 11 the view of a preferred embodiment with
several storage containers, for producing a strip
or foil with juxtaposed areas of different materials
or qualities.
Fig 12 a plan view of a cooling drum with a
segmented surface structure.
Fig 13 the drum according to Fig 11 in a sectional
view.
Fig 14 a plan view of a cooling drum with a
perforated surface structure.
Fig 15 the drum according to Fig 14 in a sectional
representation.
Fig 17 the drum according to Fig 16 in a sectional
representation.
Fig 18 another embodiment in sectional representation.
Fig 19 a plan view of the embodiment according to
Fig 18.
DETAILED DESCRIPTION OF THE PREFERRED E~BODIMEN'L`S
The apparatus for performing the methods
shown in diagrammatic manner in Fig 1 contains
a continuously rotating drum 1, which acts as
a cooler, storage container 2 with one or more
nozzles 3, e.g. with one nozzle slot, and an
inductive heater 4 for heating the melt in the
storage containers 2. A random different temperature-
stabîli2ing device can be used in place of the
inductive heater.
The storage containers 2 contain a molten
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metal, which is optionally supplied from a source 5. Both
the storage container 2 and also the complete apparatus can
he connected to an inert gas system, which is diagrammatical-
lye indicated in Fig. 1 by a was container 6 collected to the
s~oragc container 2. The area of the nozzle opening can also
be surrounded by a protective gas atmosphere or be included
in a vacuum. To avoid possibly unwanted influences of the
border layer, the nozzle outlet can be covered by electron
static fields. The storage container 2 can also be subject
to the action of a slight overpricer from gas container
6. It is also possible -to use random other devices for pro-
during a pressure difference between a storage container and
the nozzle openings, e.g. per so known mechanical or electron
magnetic pressure difference generating means A regulated
power supply means 7 is connected to inductive heater 4.
For the better detachment of the forming strip 8 from drum 1
it is possible to provide a stripper nozzle 90 for air or
protective gas, which is connected to a reservoir 100.
In the represented embodiment, the nozzle configu-
ration 3 according to Fig. 1 comprises a plurality of India
visual nozzles in the manner described hereinafter. En-
sentially, a distinction is made between two construction
types, which can be combined with one another. In a first
construction type, as shown in Fig. 2, a single nozzle body
integrated with the storage container 2 is provided, which
in the represented embodiment contains three individual slots
PA, 3B, 3C. In a
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second construction type, which is diagrammatically
shown in Figs 3, 4 and 5, a plurality of nozzle
bodies is provided, which can in each case contain
either individual nozzles 3 or nozzle groups 3AJ 3B~
3C and which are in each case connected to separate
storage containers PA, 2B, 2C.
The slot nozzle 3 comprising nozzle
openings 3AJ 3B, 3C according to Figs 2 and 3
runs at right angles to the movement direction Y
ox drum 1 and substantially parallel to the drum
surface. Nozzle openings PA, 3B, 3C are juxtaposed
in such a way that the molten metal flowing out
of the storage container 2 or storage containers
PA, 2B, 2C forms a continuous, closed melt Oil the
surface of drum 1 acting as a substrate. Drum 1,
constructed as a cooler, within the melt coating
produces a temperature drop, which leads to the
immediate solidification of the melt and to the
formation of a mechanically closed material web
on the substrate. Through the selection of the
melt temperature, e.g. with the aid of a
regulatable power supply means 7, as well as
by the choice of the movement speed of drum 1
and the choice of the temperature gradients on
the substrate surface, it is possible to produce
material webs having different structures, i.e.
mainly an amorphous or a crystalline structure.
Such crystal structures can be determined on
the finished product, e.g. by X-ray diffraction
measurements. Crystalline materials show characteristic
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sharp diffraction lines, whereas in the case
of amorphous material, the intensity on the X-ray
diffraction pattern only changes slowly with
the diffraction angle.
When using separate nozzle bodies which
are connected to separate storage containers PA, 2B,
it is possible two produce material webs, which
contain yin juxtaposed manner an amorphous/arnorphous
or amorphous/crystalline structure. A foil produced
in this way appears as a closed maternal web but
which in different areas has the known varying
characteristics for crystalline or amorphous
structures. For example, a foil produced in this
way, is highly elastic and stable in the central
area, whereas it is soft and consequently easily
deformable in the edge areas, so that it is
eminently suited as a packaging foil. A more
exacting field of use consists of the production
of juxtaposed and interconnected printed conductors
with normal and superconducting regions on a foil.
Such foils can be used in the production of high-
field coils for fusion plants.
According to the embodiment shown in
Figs 4 and 5, the nozzle heads are displaced
from one another in separate storage containers
PA, 2B, 2C in the movement direction Y of drum 1.
Thus, the action areas of the nozzles or nozzle
groups belonging to the individual storage con-
trainers follow one another in pointless manner at
right angles to the movement direction Y of drum 1.
This arrangement permits the production of
different material webs which directly link
regions of different material, the transitions
between the regions being along a sharp dividing
Kline. This is achieved by controlling the method
pa.ratneters, the melt temperature, the spacing
between the nozzles and the movement speed of
the drum surface, in such a way that a second
melt with a different composition from the second
storage container By is directly melted on the
already solidified melt from storage container PA.
This leads to the formation of a unitary material
layer, which can be removed as an entity from
the drum surface.
In order to obtain optimum connection
regions between the nozzle openings PA, 3B, 3C,
it is particularly advantageous to -reciprocally
displace juxtaposed nozzle openings in movement
direction Y, of Figs PA and 6B. Such nozzle modules
PA, 8B, 8C can be used individually or positively
juxtaposed in plural form on the bottom of a
storage container 2. Such a nozzle module contains
several nozzle openings PA, 3B, 3C with a slot
width a, a slot length b, a displacement c and
an overlap do This arrangement leads to particularly
advantageous uniform covering of the action areas
of the nozzle openings The following values have
proved to be particularly advantageous: a= 0.3 to
O.8mm, b = 20 to loom, c = O to 5mm and d = O to 3mm.
Figs 7 to 9 show further advantageous embodiments
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of such nozzle modules. According to Figs PA to
7C, the juxtaposed nozzle modules have a through
or continuous nozzle slot 3. According to Fig PA,
the abutting surface between the Nodules is at
right angles to the nozzle slot. Fig 7B shows
sloping abutting surfaces, which in practice leads
to particularly good transitions between the
individual nozzle modules, so that it is virtually
impossible to detect interfaces Oil the product
produced. According to Fig 7C, there are curved
abutting surfaces between the modules, which
particularly advantageously permit a self-centering
of the through nozzle slot.
Each of the nozzle modules according to
Fig PA contains a slot nozzle and sloping abutting
surfaces. According to Fig 8B, a module contains
several, and in the specific embodiment, two
displaced slot nozzles, sloping abutting surfaces
being provided between the modules and the nozzle
slots are also displaced via the interfaces. However,
in the case of the nozzle slots according to Fig
8C, they are continuous over abutting surfaces at
right angles to the Nazi slots.
Fig 9B shows an embodiment, in which
juxtaposed sloping nozzle openings overlap one
another in such a way that the bent or extended
ends of these openings overlap the adjacent nozzle
module, so that no special starting and finishing
modules are required.
According to a preferred embodiment for
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producing an amorphous strip from the alloy
Fe40Ni40B20, an apparatus according to Figs
l and 2 was used, in which a multiple nozzle
arrangement had an overlap G of lam, a displacement
D of 3mm, a nozzle slit width of 3mm and a distance
between the nozzles and the substrate surface of
0.3mm. A casting speed of 1.2 krn/min is obtained
for a drum rotation speed of 1200 rum and drum
diameter of 30cm.
According to a further embodiment, in
which a modular nozzle according to Fig 7 was
used, the size of the individual nozzle was
2.0 x 0.3 x 35mm, with the distance between the
nozzle and the substrate surface 0.3mm. The casting
speed was the same as in the previous embodiment.
It has proved advantageous to so select
the distance d between the nozzles and the substrate
surface, that it is on the one hand larger than
the thickness of the strip or layer to be produced
but on the other hand is smaller than 0.5mm. In
order to produce amorphous strips or layers, a
casting speed in the range 1.2 to 2.0 km/min
has proved particularly advantageous for the
aforementioned preferred embodiments. In the
embodiment, strips with a width of 5 to 30cm were
produced
By means of the described methods and
apparatuses, it is possible to produce in a
particularly advantageous manner foils from
alloys, e.g. with No and Pod for catalytic reactions,
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Quote; Quizzer, Nasser, and Mann alloys, e.g. for
hydrogen reservoirs) as well as soldering foils
based on iron for welding stainless steel and
nickel alloys for joining ceramics with metal
parts It is also possible to produce transformers
plates or Ge-containing or Si-containing alloys
for semiconductor purposes or carrier material,
e.g. silicon solar cells can be coated therewith.
It is also possible to produce superconducting
alloys in this way. According to the described
method, such high-quality foils can be held on
the edges of less valuable transport materials
which permit the mechanical working of such foils
with the aid of transport means acting on the edge,
lo whilst protecting the useful foil.
By means of such products, or when
using the described method, it is possible to
produce composite materials of the most varied
types, e.g. different metal alloys in sandwich
form, or within the scope of the isostatic mounding
of fibrous materials, strips and the like. Using
the foils or strips produced by the method according
to the invention, it is also possible to clad or
line pipes or transport lines, so that they ego
have a corrosion-resistance surface of high
quality material, whilst the carrier material
can be a simple, inexpensive mass-produced product
Large-area coatings of this type can be
realized by several butting material webs, the
abutting regions between the juxtaposed material
webs being subsequently treated in a following
stage in such a way that a homogeneous surface
of uniform thickness is obtained. The additional
step can, for example, be performed with the aid
of laser glassing The material coatings in the
abutting regions are briefly locally melted to
an adjustable penetration depth. The cooling
potential of the surrounding material is sufficient
to permit the solidification in glass-like manner
of the melted-on volume with very high cooling
rates, e.g. in the range 10 and 10 Schick so
that once again an amorphous material structure
can be produced. By means of this method, it is
possible e.g. to upgrade the surfaces of pipes or
shafts and work pieces with relatively large
dimensions can also be provided with an age-
hardened or hardened surface.
The apparatus for performing the method
shown in Fig 2 contains a continuously rotating
drum 1 acting as a cooler, a storage container 2
with at least one nozzle opening 3 and an inductive
heater 4 for heating the melt in storage con-
trainer 2. Nozzle opening 3 is at a distance d
from the surface of drum 1. Storage container 2
contains a molten metal, or a metal alloy or
metallic oxide, which is optionally supplied from
a source 5. Both the storage container 2 and thy
complete apparatus can be operated as a pressure
or inert gas system, which is diagrammatically
indicated in Fig 1 by a pressure container 6 connected
-16-
to storage container 2. A regulated power supply
means 7 is connected to the inductive heater 4.
The melt flowing from storage container 2
forms a thin melt coating on the surface of drum 1
' 5 acting as a substrate. The drum l, which is
constructed as a cooler, produces a temperature
gradient within the melt coating "which leads to
the immediate solidification of the melt and to
the formation of a closed material web on the
substrate. By the choice of the melt temperature
with the aid of the regulatable power supply
means 7, as well as by the choice of the speed of
movement of the substrate, i.e. in the present
case the speed of revolution of drum 1, together
with the choice of the temperature gradient on
the substrate surface, it is possible to establish
whether the material web produced by a mainly
amorphous or mainly crystalline structure. Such
crystal structures can be determined on the finished
product, e.g. by X-ray diffraction measurements.
Crystalline materials reveal characteristic
shaft diffraction lines, whereas with amorphous
material the intensity in the X-ray diffraction
diagram only slowly changes with the diffraction
angle
When using separate storage containers PA,
2B, 2C according to Fig 11, it is possible to
produce material webs, which contain in juxtaposed
manner the same or different materials with
different crystal structures (crystalline or
2 2 I
amorphous. A foil produced in this way appears
as a mechanically unitary strip. The individual
storage containers PA, 2B, 2C contain e.g.
different metals or alloys, which solidify to
a unitary strip on drum 1.
According to a variant, of Fig 11, there
are three cooling means PA, 8B, 8C, which supply
the drum 1 in areas lay lo and lo with a fluid
coolant, e.g. air or inert gas. By the choice of
suitable cooling capacities with the aid of cooling
means PA, 8B and 8C, it is possible to produce
different temperature ranges on the drum surface
in areas lay lo and lo. The melts flowing out of
storage containers PA, 2B and 2C are therefore
quenched to a varying degree on striking the d-rum
surface, so that a desired crystal structure can
be. obtained on one of the drum areas lay lo and
lo within the resulting closed material web.
The aforementioned method also makes it
possible to produce a closed material web from
juxtaposed areas of a different material. In this
case, the corresponding melt of the desired material
is filled into storage containers PA, 2B, 2C and
on the drum surface is provided a joint-free
engaging closed web with juxtaposed areas of
different material. The cooling conditions on the
drum surface are set by means of cooling means PA,
8B, 8C using per so known criteria, in such a way
that the solidification conditions on the dim surface
are adapted to the selected removal rate, it to the
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rotation speed of the drum.
According to Figs 12 and 13, the drum
surface is provided with separating ribs PA, 9B,
9C, which separates from one another intermediate
substrate regions loan lob Foil segments form
in substrate regions loan lob and are only slightly
separated from one another in the vicinity of the
separating ribs PA, 9B, 9C, so that the resulting
strip-like material can be removed from the drum 1
as an entity and the segments can be easily
separated from one another in a subsequent
processing stage, e.g. during the final working
of the foils.
According to the embodiment shown in
Figs 14 and 15, perforations lea, lob, llC are
provided in the drum and can have random configuratiolls.
The perforated regions of the drum surface are not
wetted by the melt applied, so that there are
corresponding recesses in the resulting strip-like
material This makes it possible to obviate the
hitherto conventional additional process stages
such as stamping or punching. Thus, a high degree
of further process ability is achieved directly at
the time of the production the foils or strips. As
a modification of this embodiment it is possible
to produce projecting areas instead of recesses
on the drum surface, so that the resulting strop-
like material has a corresponding shape.
The embodiment according to Figs 14 and 15
also makes it possible to combine different materials
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or material characteristics in juxtaposed areas.
In the embodiments shown in Figs 16 and
17, the cooling drum has on its surface profiles
AYE, 12B, e.g. rib prowls which unlike in the
case of the embodiment of Figs 3 and I have smooth
transitions, so that the ribs are uniformly coated
by the melt and a corresponding foil-like or strip-
like material forms. Such a material is used as
a top-quality semifinished product, e.g. in the
production of catalyst foils in chemical engineering.
In embodiments according to Figs 18 and 19,
the drum 1 has periodic transverse grooves 13.
When using a fine nozzle opening 3) this makes
it possible to produce material fires, whose
length corresponds to the spacing between the
transverse grooves. In the present embodiment,
drum 1 has a diameter of 280mm. The fire length
of 2cm was obtained by segmenting the drum in
2cm spacings. The V-shaped transverse groove 13 has
a depth of lam and an angle of 60. The drum rotation
speed is 1500 rum 9 corresponding to a casting
speed of 1.32 km/min. The nozzle used has a 0.5mm
diameter hole, whilst the distance d between the
nozzle opening and the drum was approximately 2mm.
The embodiment was carried out with a Fe40Ni40B20-
alloy. Typical fire dimensions are width 0.5mm,
length 20mm and thickness 30 sum.
Such short fires made from metallic
glasses can be used for reinforcing plastics,
ceramics or cement. They also form a starting material
-20
for mounding and sistering in the production
of compact, glass-like or finely crystalline
work pieces.
In a modified embodiment, in which the
nozzle opening 3 was in the form of a s lot,
wide foil pieces were produced. A slot nozzle
with a width of 20mm was used. The distance d
was approximately 0.3mm. The alloy used was
Fe40Ni40B20. The dimensions of a foil piece were
width 20mm, length 20mm and thickness 60 jump
According to another embodiment for
producing profiled strips or strip portions
according to Figs 16 and 17, the drum 1 had a
diameter of approximately 320mm. The drum surface
15 was provided with a slightly rounded longitudinal
profile of width 1.5mm and a projection of 0.2mm,
the speed of revolution was 1500 rum
The nozzle used was constructed as a
slot nozzle and had a width of 9mm. The distance
between the nozzle opening and the profile surface
was 0.3mm. Typical values for the dimensions of
the strip with profiled cross-section were,
according to Fig 11, width 9mm9 thickness at the
ends 45 em and thickness in the center 35 Jim.
According to another embodiment, the
previously produced foils and other semifinished
products were coated several times using the
aforementioned method, so that a semifinished
product was obtained with several coatings of
different materials or difererlt crystal structures.
2 9
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For example the drum 1, serving as a cooler,
and which constituted the substrate for the strips
or coatings to be produced, was replaced by a
suitable semifinished product, e.g. pipes or
other work pieces, which can be coated with the
aid of the described apparatus and method. Whilst
maintaining a continuous drawing speed, the semi-
finished product to be coated was moved under the
nozzle body and cooled as a function of the material
properties or thermal conductivity characteristics
of the semifinished product used as the substrate,
so that the coating with the desired crystal structure
crystalline or amorphous) was formed on the surface.
Pipes with an amorphous coating produced in this
way have a particularly high degree of corrosion
resistance, in the case of a suitable choice of the
coating material. They can be used with particular
advantage in the manufacture of chemical apparatus.
They are much less expensive than the hitherto
used solid material pipes for this purpose, because
simple, inexpensive material can be used as the
semifinished product.
