DE69910513T2 - Manufacturing method for a drawing tool made of hydraulic concrete, which is at least partially covered by a metal shell. - Google Patents

Abstract

The tool is made from a metal outer shell (9) made to the required shape and acting as a mold for a fiber-reinforced concrete filling, poured in after applying an adhesive compound which has a liquid adhesive phase (13) and a solid phase (14) to anchor the concrete in place. The liquid and solid phases are applied in sequence, so that the solid phase projects partially from the liquid phase to provide an anchoring surface for the concrete. The metal shell is produced by electrodeposition in a polymer mold.

Description

The The invention relates to the drawing tools of hydraulic concrete for steel sheets and the methods of making these tools.

The Drawing consists in starting from a pre-cut metal sheet low strength, called the "cutout" non-developable component of complex shape, called the "cuff plate".

A Drawing system comprises a plurality of drawing tools: a "head" provided "drawing punch", provided with a "bottom" and a "plate holder" "matrix"; the drawing stamp head and the matrix bottom are according to the complex Shape of the manufactured Stulpblechs and according to a complementary shape designed to be a complete insertion of the drawing die head in to get the matrix bottom.

Around a cuff plate according to the impression of the matrix bottom (or the die head) starting from a to get pre-cut sheet metal cutting, one drives while one holding the cutout in the blank holder, with the help of the drawing die head the cutout to the matrix bottom, until the head is completely in introduced the soil and fitted.

to Production of cuff plates in large quantities is used in the general drawing tools made of cast iron or steel.

to Production of cuff plates in small and medium quantities can you use less expensive drawing tools, for example Resin directly cast or machined according to the mold of the tool be machined, or made of hydraulic concrete or resin, on a surface "gelcoat" is poured.

by virtue of the weak mechanical properties of these materials in the amount of the "working surface" of these tools use these tools in contact with the sheets to be drawn quickly, resulting in too short pulling series.

• – in der Druckschrift FR 2 669 842 für Harzbeton,
• – in der Druckschrift US 1 935 916 für hydraulischen Beton,
• – oder in dem Artikel mit dem Titel "A functional approach to die and process development: the "composite" die and hydroforming" – Autor: G.GALLINARO – Revue: ATA – Ingegneria Automotoristica, November-Dezember 1997, Vol. 50, Nr. 11/12, Seiten 635-646 beschrieben wird.

In order to increase the surface condition and wear resistance of these tools, it is therefore necessary to reinforce these materials at the level of the work surfaces by providing them with a metallic "skin" or "shell" such as, for example

• - in the publication FR 2 669 842 for resin concrete,
• - in the publication US 1,935,916 for hydraulic concrete,
• - or in the article entitled "A functional approach to the process development: the" composite "the and hydroforming" - Author: G.GALLINARO - Revue: ATA - Ingegneria Automotoristica, November-December 1997, Vol. 50, no 11/12, pages 635-646.

The metallic "skin" or "shell" then serves as a carrier for the hydraulic Concrete or resin and forms at least partially the "working surface" of the tool, the comes into contact with the sheet to be drawn.

The metal shell can be removed by drawing, by spraying metal particles, as in the publication FR 2 669 842 be prepared by electroplating, or by chemical vapor deposition or by other methods.

These Metal shell generally has a thickness of more than 1 mm.

The The invention relates to a drawing tool made of hydraulic concrete, the provided with a metallic skin.

• – Herstellen einer Metallschale mit einer sogenannten "Außenseite", die der vorbestimmten Form des Stulpblechs entspricht, und einer gegenüberliegenden, sogenannten "Innenseite",
• – Herstellen einer Form für das Ziehwerkzeug, indem die Schale als Boden oder Formelement verwendet wird, wobei die Innenseite ins Innere der Form weist, und ggf. unter Verwendung weiterer Formgebungselemente,
• – Gießen einer Herstellungs-Zusammensetzung des Betons in die Form, und Erstarren der Zusammensetzung,
• – Ausformen der erstarrten Zusammensetzung, wobei die möglichen weiteren Formgebungselemente entfernt werden, während die Schale, die durch Kleben mit dem erstarrten Beton verbunden ist, an Ort und Stelle gehalten wird.

In order to produce a hydraulic concrete drawing tool whose surface, intended to come into contact with the sheet metal cutout to be drawn, is at least partially covered by a metal shell, a method is known comprising the following steps:

• Producing a metal shell with a so-called "outside" which corresponds to the predetermined shape of the cuff plate, and an opposite, so-called "inside",
• - Making a mold for the drawing tool by using the shell as a bottom or molding element with the inside facing the inside of the mold, and possibly using further shaping elements,
• Casting a manufacturing composition of the concrete into the mold, and solidifying the composition,
• - Forming the solidified composition, wherein the possible further shaping elements are removed, while the shell, which is connected by gluing with the solidified concrete, held in place.

The Metal shell and the concrete have very different mechanical Properties; while a drawing cycle, especially at the end of the cycle, the interface between Shell and concrete very big Exposed to shearing stresses, especially in the areas which has a small radius of curvature exhibit; These heavy loads can locally break the connection between the concrete and the shell effect what the benefits of the tool limits.

To strengthen the connection between shell and concrete in the case of using resin concrete, pour according to the document FR 2 669 842 prior to pouring the resin concrete, an intermediate layer of a bonding resin that is compatible with the resin of the concrete (see page 4, lines 27 to 32).

In order to strengthen the connection between shell and concrete in the case of the use of hydraulic concrete, according to the publication US 1,935,916 provide the inside of the metal shell with mechanical means for anchoring the concrete (see page 2, lines 61 to 67); no adhesive composition is applied prior to pouring the concrete.

If gluing is a bonding technique well suited to the resin concrete is, but it is less suitable for hydraulic concrete, since the to water of hydraulic concrete on an adhesive layer the water of the Would prevent composition that a sufficiently strong bond at the interface of Adhesive and concrete is obtained.

It was actually found that the connection between an adhesive and a "fresh" or "wet" concrete in general had much less good shear strength performance as the bond between the same adhesive and an "old" concrete, i. a "hardened" and dry concrete: Example 1 below illustrates this performance degradation represents.

at Use of a hydraulic concrete so you can see from the use the adhesive technology.

In addition, the document describes US 1,935,916 mechanical anchoring means coupled directly to the metal shell (reference 16 in the figures); Such a type of connection between shell and concrete is therefore very expensive.

The Invention has the goal of the connection between shell and concrete a drawing tool made of hydraulic concrete to improve economically and to improve the performance of this tool.

• – Herstellung der Metallschale derart, dass sie eine sogenannte "Außenseite", die der vorbestimmten Form des Stulpblechs entspricht, und eine entgegengesetzte, sogenannte "Innenseite" aufweist,
• – Herstellung einer Form für das Ziehwerkzeug, indem die Schale als Formboden oder Formelement genommen wird, wobei die Innenseite zum Inneren der Form ausgerichtet ist,
• – Gießen einer Zuschlagstoffe enthaltenden Zusammensetzung in die Form zur Herstellung des Betons,
• – Erstarren der Zusammensetzung,

dadurch gekennzeichnet, dass vor dem Schritt des Gießens eine eine flüssige Klebstoffphase und eine feste Phase enthaltende Klebstoffzusammensetzung auf die Innenseite aufgebracht wird, die geeignet ist, um mechanische Mittel zur Verankerung im Beton zu bilden.For this purpose, the invention has a method for producing a drawing tool made of hydraulic concrete to the object, which is suitable for the production of Stulpblechen predetermined shape starting from sheet metal cutouts, tool whose surface, which is intended to get in touch with the sheet metal cutout to be pulled , at least partially covered by a metal shell, comprising the following steps:

• Manufacture of the metal shell in such a way that it has a so-called "outside" which corresponds to the predetermined shape of the faceplate and an opposite, so-called "inside",
• Making a mold for the drawing tool by taking the shell as a mold bottom or mold element with the inside aligned with the interior of the mold,
• Pouring an aggregate-containing composition into the mold for producing the concrete,
• - solidification of the composition,

characterized in that, prior to the step of casting, an adhesive composition containing a liquid adhesive phase and a solid phase is applied to the inside suitable for forming mechanical anchoring means in the concrete.

Of the Term "liquid adhesive phase" refers to a usual, in liquid Form applicable adhesive.

Of the Term "solid phase" refers to anchoring elements, which are homogeneously distributed in the adhesive composition.

With receives this manufacturing process to have an economic and very solid connection between the Metal shell and the concrete.

When Mechanical anchoring agents can be conventional mineral aggregates used, which is very economical; to the connection between shell and concrete still reinforce, it is preferably used Aggregates of the same type as those of the concrete composition; the granule size of the aggregates the adhesive composition is adjusted to allow the aggregates after applying partially from the liquid phase of the adhesive composition protrude.

Further advantageous features of the method according to the invention are in the dependent claims specified.

• – der Schritt der Herstellung der Schale enthält die folgenden Schritte:
• – Herstellen eines Abdrucks mit einer Oberfläche, die der vorbestimmten Form des Stulpblechs entspricht;
• – gegebenenfalls die Oberfläche des Abdrucks leitend machen;
• – Bedecken der Oberfläche oder ggf. der leitenden Oberfläche des Abdrucks durch galvanisches Beschichten mit einer Metallschicht, bis eine Metallschale gebildet ist, wobei die Innenseite der Schale dann der metallischen Schicht am Ende der galvanischen Beschichtung entspricht;
• – die Metallschicht ist auf der Basis von Nickel, und die galvanische Beschichtung erfolgt in einem Bad zur galvanischen Beschichtung auf der Basis von Nickelsulfamat;
• – die Metallschicht ist auf der Basis von Kupfer,
• – der Abdruck ist aus Polymermaterial und/oder die leitende Oberfläche des Abdrucks enthält Graphit.

When the shell is made by electroplating, the invention may also have one or more of the following features:

• The step of manufacturing the shell includes the following steps:
• - Producing an impression with a surface corresponding to the predetermined shape of the Stulpblechs;
• - optionally make the surface of the impression conductive;
• - Covering the surface or possibly the conductive surface of the impression by electroplating with a metal layer until a metal shell is formed, wherein the inside of the shell then corresponds to the metallic layer at the end of the galvanic coating;
• - The metal layer is based on nickel, and the galvanic coating takes place in a bath for galvanic coating based on nickel sulfamate;
• The metal layer is based on copper,
• - The impression is made of polymer material and / or the conductive surface of the impression contains graphite.

The Invention also has a drawing tool made of hydraulic concrete for Object whose surface, which is intended to be in contact with the sheet metal section to be drawn to arrive, at least partially connected with a concrete Metal shell is covered by the method of the invention can be obtained, characterized in that the shell with the concrete is connected by means of an adhesive layer, wherein Mechanical anchoring means partly in the concrete and partly inserted into the adhesive layer are.

Further advantageous features of the drawing tool according to the invention are in the dependent claims specified.

The The invention will be better understood with reference to the following Description in which the shell is made by galvanic coating this description being given as a non-limiting example to understand.

The The following examples serve to give more detail to this description to illustrate, still without restriction and in relation to:

1 which is a schematic diagram of shear tests of Example 1;

the 2 to 4 which correspond to various steps of the production of a drawing tool by the method according to the invention, as described in Example 2: 2 : Making the impression 3 : Making the shell 4 : Drawing tool according to the invention.

The Method for producing a drawing tool according to the invention thus contains mainly the following steps: production of the metal shell, production of a mold for the this metal shell integrating concrete, producing a concrete composition, Preparation and application of an adhesive composition for the compound of concrete and shell, casting of the concrete, solidification of the concrete and cross-linking of the adhesive, Forming the concrete.

• – Herstellen eines Abdrucks mit einer Oberfläche, die der vorbestimmten Form des Stulpblechs entspricht;
• – gegebenenfalls die Oberfläche des Abdrucks leitend machen;
• – Bedecken der leitenden Oberfläche durch galvanisches Beschichten mit einer Metallschicht, bis eine Metallschale gebildet ist, wobei die Innenseite der Schale dann der Stärke der metallischen Schicht am Ende der galvanischen Beschichtung entspricht.

To produce a metal shell by electroplating or electroforming, the document describes DE 40 21 384 a method comprising the following steps:

• - Producing an impression with a surface corresponding to the predetermined shape of the Stulpblechs;
• - optionally make the surface of the impression conductive;
• - Covering the conductive surface by electroplating with a metal layer until a metal shell is formed, wherein the inside of the shell then corresponds to the thickness of the metallic layer at the end of the galvanic coating.

you can make an impression, for example, by giving one Block from a soft material precedes and then machine machined to bring it exactly to the desired dimensions.

When Soft material can be a composite material with organic matrix Use, for example, starting from a thermosetting Resin is made of the fillers added become; if these fillers are conductive, one can obtain an electrically conductive composite material.

you can also imprint by molding on a "master model" of a resin, a resin concrete or a hydraulic concrete on a "gelcoat" or a any other, compatible with the requirements of electroforming Material obtained, these requirements in particular the temperature and the chemistry of the bath for plating and surface condition of the impression.

A The sides of the impression must therefore be the predetermined shape of the faceplate correspond; the condition of this surface requires those of surface the drawing tool and also the easy separation of impression and Shell, generally after casting the concrete; so it is especially important, its surface condition to consider, and surface treatments, such as polishing, can become useful for this purpose prove.

Around to guarantee the geometry of the electroformed component, and in particular, when the electrolyte coating in a bath with the ambient temperature is different temperature should for the Impression a material can be used, the coefficient of expansion coefficient near that of the shell's metal, or that coefficient should be at the original Dimensions of the impression taken into account become.

So it is usual, Copper shells in plating baths at ambient temperature to produce while Nickel shells made by galvanic coating at temperatures which are generally higher lie at about 55 ° C.

If the material used to make the impression is non-conductive is the side of the footprint should be made conductive, the Shape of the faceplate corresponds, so that when immersing this area in a Bath for electroplating a galvanizing current between this area and a counter electrode immersed in the bath can.

you can the surface For example, by applying a layer of a current-conducting paint or by chemical or physical application of a conductive Make material (for example silver or palladium) conductive; preferably contains the conductive material graphite.

If the strenght the applied layer with respect to the dimensional tolerances the tool is too big, must be in the surface before of the impression a draft over a Depth executed which corresponds to that of the lacquer layer; the surface quality of the applied Layer is as important as the impression, as above described.

Around the strenght limit this layer and get a conductive surface which reproduces the one of the impression in more detail, is preferably before a chemical or physical coating instead of a paint coating carried out.

Of the contains the following step a galvanic coating process that is adapted around the conductive surface to coat with a metal layer of a thickness capable of is to form the metal shell of the drawing tool.

When galvanic coating material, which is a shell of a pulling tool You can form nickel or copper or alloys of these Use metals such as nickel cobalt alloys.

The Strength the metal shell hangs from the shape of the faceplate, the mechanical properties the concrete of the tool and the metal of its shell, and the intended conditions of use of the tool; so to effect Example complex shapes of the faceplate, the low radii of curvature exhibit, heavy demands on the shell, and require one greater strength; the Strength, which should be awarded to the shell, by known per se Procedures are calculated, which are not described here in detail become; this strength is generally over 1 mm.

For the galvanic Coating so you dip the conductive surface in a bath for galvanic coating and lets a galvanizing current between this surface and a counter electrode immersed in the bath flow.

The Conditions of the galvanic coating, as well as the composition and the temperature of the bath, such as the current density and the plating charge, be in a conventional manner depending on the composition and the strength adapted to be applied metal layer; this applied Layer forms the metal shell of the drawing tool.

at Nickel shells are therefore preferably used baths, mainly nickel sulfamate and nickel chloride and boric acid contain; you can use these baths add organic additives, which are suitable for the mechanical properties of the metal shell to improve.

There the galvanic initial coating is intended to be the working surface of the Drawing tools are the coating conditions during this Phase especially important; especially in the case of low conductivity the conductive layer of the impression, and / or a homogeneous galvanic Good quality coating and to get from little roughness, it is appropriate during this Phase to apply a very low current density, much lower as 1 A / dm2; subsequently elevated the current density according to the Bath allowed performances and according to the limits the internal tensions allowed in the applied strength are.

The Nickel sulfamate-containing baths enable it to achieve high coating speeds, whereby the Production costs can be reduced.

For medium Current densities, generally below 10 A / dm2, can be as thick metallic Obtained nickel layers having a Vickers hardness between 150 and 250 HV, a elastic limit voltage between 250 and 660 MPa, a breaking limit voltage between 370 and 1050 MPa.

The Add of cobalt in the bath allows it, the hardness to increase the obtained metal; the increase the current density generally causes a reduction in hardness.

To the galvanic coating gives a metal shell, the with its so-called "outside" against the impression is present while the free area the shell forms the so-called "inside" of the shell, the strength the applied metal layer at the end of the galvanic coating equivalent.

In At this stage one can separate the shell from the impression; it will but prefers to perform this separation later.

outgoing of mold elements is then made a mold for the drawing tool, wherein the metal shell as a mold bottom or mold element with the "inside" to the interior of Form is used directionally; Other features are on the Outline of the shell arranged to form a shape that matches the dimensions adapted to the drawing tool to be produced; these other elements can be attached to the impression of the shell.

Then is in a conventional manner a composition of a hydraulic Concrete manufactured for the production of a drawing tool is suitable; It is about generally to so-called "BHP" compositions ("high performance concrete") or high performance concrete compositions, the except the usual Constituents of the concrete, i. a hydraulic binder and Aggregates, fumed silica and a superplasticizer included.

The Aggregates consist for example of sand and / or gravel.

For these "BHP" compositions are the proportion of mixing water and the solidification Schwin very low.

The full Solidification of these types of concrete can be achieved by storage at ambient temperature while be received for at least 28 days; It can also be accelerated Obtained by heat treatment become.

For this Receives compositions one after the full one Solidification of concrete types whose breaking limit stress exceeds 50 MPa under compressive stress and 7 MPa in tensile stress.

Preferably contains the concrete-making composition used reinforcing fibers; allow these metal fibers it to limit the propagation of cracks in the concrete, which makes it possible its compressive strength, especially under tensile load, and its fatigue strength to increase and to improve the performance of the drawing tool yet.

you then sets makes an adhesive composition and wears it on the inside of the as a mold bottom or form element serving metal shell.

you For example, this is done as it is in the experiments Nos. 4 to 6 or No. 13 to 15 of Example 1 is described; according to these inventive experiments is dispersed to prepare an adhesive composition in the one from a usual Adhesive for Gluing on concrete is suitable, existing liquid phase a solid phase that is adapted to mechanical means of anchoring to form in the concrete.

Preferably this adhesive is based on thermosetting polymers, for example of the type epoxy; these types of adhesives are generally two-component adhesives, the mixture of organic ingredients is about to be used he follows; Preferably, this adhesive is suitable for getting under to fully network the solidification conditions of the concrete.

The Use of adhesives based on thermoplastic polymers should be avoided as the cohesion between shell and concrete of the tool by heating of the drawing tool during could worsen the use with fast power stroke, what the performance of this tool has been severely impaired.

The mechanical anchoring means have at least one dimension, perpendicular to the surface the metal shell runs, after applying to this shell over the surface of the liquid phase the adhesive composition so that after pouring the Some concrete these anchoring agents in the adhesive layer and partly submerged in the concrete.

• – isolierte Elemente, wie die mineralischen Zuschlagstoffe oder die Metallnägel, die im Beispiel 1 angeführt sind;
• – ein "zweidimensionaler" Draht von der Art "Stacheldraht" oder ein "dreidimensionales" Gitter, mit in gleichmäßigem Abstand angeordneten Elementen, die quer zur allgemeinen Richtung des Drahts bzw. des Gitters verlaufen, von denen mindestens ein Ende in den Beton eingetaucht werden soll.

As mechanical anchoring means can be used:

• - isolated elements, such as the mineral aggregates or metal nails listed in Example 1;
• A "two-dimensional" barbed wire or a "three-dimensional" lattice, with evenly spaced elements running transversely to the general direction of the wire or lattice, at least one end of which is to be immersed in the concrete ,

The Use of aggregates has an economic advantage and an advantage in terms of anchoring in concrete, especially if these aggregates of the same kind as those of the concrete are.

Around Applying the adhesive composition generally begins with it, the inside of the metal shell with a uniform layer a usual one Adhesive in the liquid To coat condition, and then you wear the anchoring means by allowing them to penetrate into the adhesive layer in the liquid state; it It is very important that these anchors are partly in the Adhesive layer are immersed and that the other part from the free surface the adhesive layer protrudes to later submerged in the concrete to become; after the pouring of the concrete the anchoring agents in both the thickness of the adhesive layer as also be immersed in the concrete.

Preferably is the dimension of the anchoring means perpendicular to the surface of the Shell or to the surface the adhesive layer runs, greater than the strenght the applied adhesive layer.

at one uses isolated anchoring agents Means preferably by placing them evenly on and in the adhesive layer distributed.

Of the Advantage of using a wire or grid as anchoring means lies in the fact that the anchoring means of this wire or be worn on this network, were previously distributed regularly.

Then you can one to the process of casting of the concrete composition into the mold.

• – kann man in Abhängigkeit von der Art des verwendeten üblichen Klebstoffs den Klebstoff in an sich bekannter Weise teilweise vernetzen lassen;
• – kann man gegebenenfalls Verstärkungsarmierungen des Betons und Metalleinsätze vorsehen, die man dann in der Form anordnet.

Before pouring:

• - Can be partially crosslinked in a conventional manner, depending on the type of the usual adhesive used;
• - You can optionally provide reinforcing reinforcements of the concrete and metal inserts, which are then arranged in the form.

Then pouring The concrete composition in the form, shaking the concrete in the liquid state, to to degasify and condense it, then let this concrete in known and adapted to the concrete composition used Freeze way; Under the solidification conditions is the adhesive the adhesive composition completely crosslinked.

To the solidification, or at least after the onset of solidification, as soon as possible the adhesive of the adhesive composition is fully crosslinked is, one can form, by, if necessary, the other form elements removed, except the metal shell, which by gluing and anchoring firmly with the concrete connected is.

If The adhesive is suitable to under the solidification conditions of the concrete completely To network, it is not necessary to take a separate step Networking after casting of the concrete.

Of the Adhesive guaranteed then a chemical bond between the shell and the concrete while the mechanical anchoring means essentially a mechanical Ensure connection, since both in the layer of cross-linked adhesive and in the solidified concrete are submerged.

Of the Advantage of using aggregates as anchoring agents lies in the fact that the distances between the anchoring points are very small, especially if the average diameter of these aggregates is relatively low, i. between 1.5 and 3 times as big as the strenght the liquid Phase of the adhesive composition after application.

you can also aggregates not only of the same kind, but also of the same granule size as those use the concrete composition, which is more economical.

It is also appropriate, if not already done, the impression to separate from the metal shell, exposing the outer surface of the shell, the work surface of the drawing tool corresponds.

If is the impression of polymer material, and / or if on this Imprinted conductive layer based on graphite This separation is advantageously facilitated.

So receives a drawing tool made of hydraulic concrete, for the production from Stulpblechen a predetermined shape starting from sheet metal cutouts suitable tool, whose surface, with the to be pulled Sheet metal section should come into contact, at least partially by a metal shell is covered.

The Production of the tool can be achieved by a light machining, to, if necessary, to correct the dimensions of the tool, and / or by a Treatment of the work surface, to harden her, and / or to adjust their roughness and / or the lubricity to improve when pulling, to be completed.

One can on the metal shell of the tool the same surface treatments as those which are used in conventional cast-iron drawing tools; during heat treatments, care should be taken not to reach temperatures which could damage the cross-linked adhesive of the adhesive composition which ensures the connection between shell and concrete.

by virtue of The invention provides the drawing tool benefits that in comparison with the drawing tools of the same kind according to the state The technique is much improved because the connection between the shell and the concrete is very strong, especially against the Abscherbeanspruchungen; improving the strength of this compound in comparison with the prior art is in the following example 1 shown.

With Help the invention can At a reduced cost, drawing tools are manufactured for larger series of production of faceplates and / or for Stulpbleche can be used with more complex forms, the is called Shapes, the small radii of curvature exhibit.

The complete the following examples the description.

Example 1:

This Example aims to increase the effect of the solid added to the adhesive Anchoring means on the strength of the connection between the To represent shell of a drawing tool and the concrete which one in this bowl is pouring.

Around To calculate this effect, one measures the shear strength of Adhesive joints between a concrete block and a metal plate be installed in accordance with the Protocol, that defined in the following §1 is for several types of adhesive joints, defined in the following §2 are; the results are in §3 specified.

1. Measurement protocol of shearing resistance from between a concrete block and a metal plate attached adhesive joints:

The principle of measurement is in 1 shown.

1.1 Making the Assembly of a Block 1 made of concrete and a metal plate 2 , which with the help of a designated adhesive joint 3 be firmly connected with each other.

The metal plate 2 consists of a bare steel sheet with a thickness of 1.5 mm; the plate is degreased with the help of trichlorethylene.

After possibly mixing the various components of the adhesive, one of the sides of the plate becomes 2 coated with adhesive, the brushing mode being adapted to the type of adhesive used (see below).

Then If necessary, the inventive mechanical Anchoring means (see below) applied; the adhesive composition contains then the glue itself and the anchoring means.

The Making the assembly is then different, depending on whether it is an assembly on "old" or "wet" concrete.

1.1.1 Assembly on "old" concrete:

Starting from concrete composition # 1 (without fibers) described in Example 2 (Table III), a concrete block is formed 1 made with parallel sides; after being held in the preservation room for at least 28 days, the resulting block has a compressive strength of the order of 55 MPa.

To get the assembly, then the adhesive plate is provided 2 on one of the sides of the block 1 hung up.

After drying under conditions suitable for the adhesive used, the verbin 3 between the block 1 and the plate 2 then ensured by the adhesive composition.

1.1.2 Assembly on "wet" concrete:

On the adhesive side of the plate 2 , and after the start of the polymerization of the adhesive (1 to 2 hours, depending on the adhesive used), a block 1 formed from concrete starting from a concrete composition identical to that in paragraph 1.1.1 above.

To the shaking the composition in the liquid State leaves you bind the concrete in the mass and dry it under the same Conditions as described above under paragraph 1.1.1, i.e. one stops the assembly at least 28 days in the preservation room.

As in paragraph 1.1.1, the connection 3 between the block 1 and the plate 2 then ensured by the adhesive composition.

1.2 Measurement of Shear Strength:

Then, the measurement of shearing strength of the joint becomes 3 performed as follows: by the block 1 between an edition 4 under its bottom and another edition 5 is held on its top, one puts a vertical force F on the plate 2 on (see arrow in 1 ) and measures the breaking force F _{r of} the connection of the joint 3 ,

The joint 3 is then mainly claimed by a shearing force.

For a more accurate calculation of the shear strength of a joint 3 to obtain at least three assemblies using the same joint, and measure the breaking strength F _r1 , F _r2 , F _{r3 of} each assembly; the mean of the three measurements obtained gives a more accurate calculation of the shear strength of the joint 3 ,

The Choice of a steel sheet explained as follows: Breaking tests were carried out beforehand by were taken as a metal plate electroformed plates under The same conditions were electroformed as those of the Metal shell of the drawing tool according to the invention; it was then found that the breakage of the compound of the adhesive joint always at the interface between concrete and glue; So one derived from it, that carried out with the help of sheet steel plates measurements to the same Results would like those done on galvano-formed plates; in order to simplify the experiments, you then have the Most measurements were done on steel plates.

2. Type of tested Concrete-metal compounds:

2.1 Type of used Adhesives and custom application mode: There were three adhesives tested:

• - "Sikadur 31" ^® from SIKA: It is a two-component epoxy adhesive suitable for bonding metals and fresh concrete to old concrete; this adhesive can be considered as a resin mortar; This adhesive is applied using a spatula with triangular teeth with a height of 2 mm.
• - "Sikadur Impregnation" ^® from SIKA: liquid two-component epoxy adhesive, suitable for bonding fresh concrete to old concrete and for concreting joints; it is a pure resin that penetrates well into the concrete; this glue is applied with the brush.
• - "Mybond Epiphen" ^® 1800 "from LAMBIOTTE: two component liquid epoxy adhesive, a pure resin commonly used in the manufacture of laminated composites and resin concrete types, this adhesive is applied in a thickness of 1 to 2 mm Casting is applied to a mold whose bottom is the metal plate, and prior to application to the plate, allowed to crosslink for about 2 hours to obtain an adhesive with a higher viscosity but sufficient liquid to pour into the mold.

2.2 Production of "composite" joint joints on "wet" concrete:

• – Doppelte Klebstoffschicht: Klebstoff "Sikadur 31" + "Sikadur Imprégnation": Man trägt zunächst auf die Metallplatte eine Schicht "Sikadur 31" auf, lässt diesen Klebstoff während etwa 2 Stunden teilweise vernetzen, und trägt dann auf diese teilweise vernetzte Schicht eine Schicht "Sikadur Imprégnation" auf, der gut für das Kleben auf porösen Materialien geeignet ist.
• – Klebstoff "Sikadur 31" + "mineralische" Verbindung: Da die Polymerisierung des Klebstoffs in einem feuchten Milieu schwieriger ist, hat man sich zum Ziel gesetzt, die Verbindung durch mechanische Verbindungen von der gleichen Art wie der Beton zu vervollständigen; nach dem Auftragen der Klebstoffschicht auf die Metallplatte verteilt man Zuschlagstoffe auf dieser Schicht vor dem Beginn der Polymerisierung; der mittlere Durchmesser der Zuschlagstoffe ist beträchtlich größer als die Stärke der aufgetragenen Klebstoffschicht; der Bedeckungsgrad der verteilten Zuschlagstoffe wird so angepasst, dass der mittlere Abstand zwischen den Zuschlagstoffen von der gleichen Größenordnung wie die mittlere Größe der Zuschlagstoffe ist; man lässt die Zuschlagstoffe in die Klebstoffschicht eindringen.
• – Klebstoff "Sikadur 31" + "metallische" Verbindung: Da die Polymerisierung des Klebstoffs in einem feuchten Milieu schwieriger ist, hat man sich zum Ziel gesetzt, die Verbindung durch metallische Verbindungen vergleichbar mit den Betonarmierungen zu vervollständigen; nach dem Auftragen der Klebstoffschicht auf die Metallplatte und vor dem Beginn der Polymerisierung verteilt man Nägel mit einer Länge von etwa 40 mm auf dieser Schicht, indem man den Kopf dieser Nägel in der Klebstoffschicht versenkt, wobei die allgemeine Richtung dieser Nägel quer zur Oberfläche der Platte liegt; der Bedeckungsgrad der verteilten Nägel ist so angepasst, dass der minimale Abstand zwischen den Nägeln größer ist als der minimale Durchmesser des Betonkiesel.

Three types of composite joints were tested on "wet" concrete, with the latter two adhesive compositions of the invention:

• - Double adhesive layer: "Sikadur 31" adhesive + "Sikadur Imprégnation": first apply a layer of "Sikadur 31" to the metal plate, allow this adhesive to partially crosslink for about 2 hours, and then apply a layer to this partially cross-linked layer. " Sikadur Imprégnation ", which is well suited for bonding on porous materials.
• - Adhesive "Sikadur 31" + "mineral" compound: Since it is more difficult to polymerize the adhesive in a humid environment, the aim is to complete the joint with mechanical joints of the same type as the concrete; after the adhesive layer has been applied to the metal plate, aggregates are spread on this layer prior to the start of the polymerization; the average diameter of the aggregates is considerably greater than the thickness of the applied adhesive layer; the degree of coverage of the distributed aggregates is adjusted so that the mean distance between the aggregates is of the same order of magnitude as the average size of the aggregates; The additives are allowed to penetrate into the adhesive layer.
• Adhesive "Sikadur 31" + "metallic" compound: Since it is more difficult to polymerize the adhesive in a humid environment, the goal has been to complete the compound with metallic compounds comparable to the concrete reinforcements; after applying the adhesive layer to the metal plate and before starting the polymerization, nails of about 40 mm length are spread on this layer by burying the head of these nails in the adhesive layer, the general direction of these nails being transverse to the surface of the plate lies; the degree of coverage of the distributed nails is adjusted so that the minimum distance between the nails is greater than the minimum diameter of the concrete pebble.

3. Results of the measurements Shear strength of various concrete-metal joints:

The obtained results, as well as the type and location of the fracture the test are listed in Table I below.

Table I - Shear Strength of the Various Concrete-to-Metal Compounds

Of the Comparison of the results of Experiments Nos. 1, 2 and 3 with those Experiments Nos. 25, 26 and 27 clearly show that an applied to "fresh" or "wet" concrete Adhesive generally significantly lower in terms of performance has the shearing resistance as the same adhesive when he on "old", i. "hardened" and dry concrete is applied.

It is therefore an essential object of the invention, this deterioration to avoid or compensate for benefits.

The Achievements obtained with other adhesives on wet concrete (Experiments Nos. 16 to 18 and Nos. 22 to 24) may be slightly higher but still inadequate to the strong tensions between the concrete and to withstand the metal shell of a pulling tool.

It Another object of the invention is a concrete-metal joint to propose, which has a much higher shearing resistance.

So show the experiments of the invention Nos. 4 to 6 and Nos. 13 to 15 that the compound compounds of the invention much more shear resistant than the "glue" compounds of the prior art wet concrete (experiments Nos. 1 to 3 and Nos. 16 to 24); The invention refers to the use of an adhesive composition, the mechanical anchoring means such as aggregates (experiments Nos. 4 to 6) or metal nails (Experiments Nos. 13 to 15).

By the use of such a composite compound for producing a Concrete drawing tool equipped with a metal shell is, cohesion will be between shell and concrete, and consequently the performance of the tool, significantly improved.

One Advantage of the composite compound according to the invention lies in reliability the strength of this compound: the dispersion of the results of Trials performed on a composite connection is indeed essential less than that of the results of the tests carried out on one classical glued connection were performed (see Table I); This advantage thus improves the reliability of the inventively produced Drawing tools.

Example 2

The aim of this example is to produce a hydraulic concrete mold according to the invention with reference to FIGS 2 to 4 display.

1. Production of the impression 6 with reference to 2 ,

It a block of a soft material is pre-cut and then machined until it accurately and precisely the desired Dimensions corresponds, and such that one of the sides 7 of the predetermined Shape of the faceplate corresponds.

When soft material can be one of the following in the table II described polymer materials use.

Table II - Examples of Polymeric Materials for Impression.

• – Dehnungskoeffizient höher als der, aber relativ nahe demjenigen von Nickel (etwa 17.10^–6) im Temperaturbereich 20-100°C,
• – Dichte höher als 1 kg/dm3 zur Vereinfachung des Eintauchens in das Bad zur galvanischen Beschichtung, Temperatur des Glasübergangs wesentlich höher als die Nutztemperatur des Bads, gute Festigkeit gegenüber der chemischen Säurewirkung des Bads und des Aufdehnens im Wasser,
• – gute maschinelle Bearbeitbarkeit aufgrund der mechanischen Eigenschaften (Druckfestigkeit, Bruchdehnung, Härte),
• – ausgezeichneter Oberflächenzustand nach maschineller Bearbeitung, insbesondere in Bezug auf die Rauheit und die Porosität, wodurch die Trennung von Schale und Abdruck erleichtert wird.

The materials described in this Table II have the following properties:

• Elongation coefficient higher than but relatively close to that of nickel (about 17.10 ^-6 ) in the temperature range 20-100 ° C,
• Density higher than 1 kg / dm3 for ease of immersion in the plating bath, glass transition temperature much higher than the useful temperature of the bath, good resistance to the chemical acidity of the bath and expansion in the water,
• Good machinability due to mechanical properties (compressive strength, elongation at break, hardness),
• Excellent surface finish after machining, particularly in terms of roughness and porosity, facilitating separation of shell and impression.

After degreasing, the side 7 is made conductive by applying a very thin layer of a conductive conductive paint containing silver particles: the impression 6 is then on its surface 7 with a conductive coating 8th Mistake; the strength of the conductive coating 8th is about one micrometer.

you may also use a paint containing graphite particles, thereby the separation of shell and impression is facilitated.

2. Preparation of a shell 9 of nickel with a thickness of about 0.8 mm by electroplating with reference to 3 ,

By electroplating in a bath, the conductive coating becomes 8th So covered with a nickel layer, which is the metal shell 9 of the drawing tool will form.

Composition of the bath for galvanic coating: Boric acid H ₃ BO ₃ : 80 g / l - Nickel chloride, NiCl ₂ , 6 H ₂ O 5 to 10 g / l Nickel sulfamate Ni (NH ₂ SO ₃ ) ₂ 200 g / l to get | Ni2 + | = 40 g / l - Wetting agent <1% by weight

Conditions of galvanic coating:

• - Bath: 4.2 <pH <4.8 and temperature between 50 and 55 ° C,
• - current density: 0.1 A / dm2 at the beginning, progressive increase up to 5 A / dm2.

Mechanical characteristics of the obtained nickel: - Elasticity limit stress (at 0.2%): 485 MPa, - Modulus of elasticity 182.5 G Pa, - Breaking limit voltage 840 MPa, - Elongation at break: 8.3% Hardness on the outside (for coating 8): 210 HV - Hardness on the inside (mold bottom) 238 HV

It was also the value of the possible Residual stresses in the thickness the nickel layer evaluated by taking measurements on the same Conditions, but on a steel sheet applied layers were carried out.

On this substrate, and unlike the conductive coating 8th or to the surface of the impression 7 , nickel is considered to be strongly adhesive; after nickel has been applied, a strain gauge is adhered to the uncovered side of the sheet and, with the aid of this measuring strip, it measures the relaxation which occurs when successive layers of the nickel coating are removed by electroerosion.

By These measurements could be calculated that the tensile residual stresses between 90 and 150 MPa.

The low altitude allows the residual stresses it, the dangers of "detachment" of certain zones of the Peeling off the imprint while the galvanic coating or before pouring the concrete, what makes it possible the consideration the geometric tolerance values of the working surface of the tool even better to guarantee.

After the galvanic coating is thus obtained on the impression 6 a metal bowl 9 which has a so-called "outside" in contact with the conductive coating 8th and an opposite, so-called "inside" has.

Taking into account the in 3 described shell 9 no element must be added here to form the casting mold of the concrete.

3. Preparation of concrete composition:

• – hydraulisches Bindemittel von der Art Zement und Sand: Mörtel mit der Bezeichnung Clavex^® Lanko 701 der Firma LAFARGE; zur Formel dieses Mörtels gehören bereits Zusatzstoffe, welche das Schwinden eingrenzen, wie zum Beispiel pyrogene Kieselerde,
• – Kies mit einer Körnchengröße zwischen 3 und 8 mm,
• – Verstärkungsfasern: amorphe Gusseisenfasern in Form von elastischen, sehr dünnen Bändern mit Abmessungen von etwa 15 × 1 × 0,03 mm, mit der Bezeichnung Fibralex der Firma SEVA.
• – Verflüssiger oder superplastifizierender Wirkstoff: mit der Bezeichnung Sikament FF86 der Firma SIKA.
• – Anmachwasser.

Compositions are made with the following ingredients:

• - hydraulic cement of the type cement and sand: mortar with the name Clavex ^® Lanko 701 of the company LAFARGE; the formula of this mortar already includes additives that limit shrinkage, such as fumed silica,
• - gravel with a grain size between 3 and 8 mm,
• Reinforcing fibers: amorphous cast iron fibers in the form of elastic, very thin bands measuring approximately 15 × 1 × 0.03 mm, called Fibralex from SEVA.
• - Condenser or Superplastifizierender agent: with the name Sikament FF86 SIKA.
• - mixing water.

The Aggregates therefore consist of the sand of the mortar and made of gravel.

It Three types of compositions are prepared that are different the proportions of these ingredients differ, as in the table III is indicated.

Table III - Concrete compositions for the drawing tool.

• – in der Spalte "Fasern", das Volumen der Fasern in Bezug auf das Betonvolumen,
• – in der Spalte "Verflüssiger", das Volumen des Verflüssigers in Bezug auf das Zementvolumen.

In this Table III the proportions are given as volume-related mass (kg / m3), the numbers in brackets indicate:

• - in the column "fibers", the volume of the fibers in relation to the concrete volume,
• - in the column "condenser", the volume of the condenser in relation to the cement volume.

The relationship E / C refers to the water weight divided by the cement weight.

4. Production and application the adhesive composition on the inside of the metal shell 9th

In Example 1, two kinds of adhesive composition are used: the first corresponds to Run Nos. 4 to 6, and the second one corresponds to Run Nos. 13 to 15; the adhesive composition is prepared and applied to the metal plate 2 applied.

Either the first or the second adhesive composition on the metal shell is used here in the same way 9 still from the imprint 6 is held.

5. Casting and solidifying the concrete with reference to 4 in the case of using the first adhesive composition (mineral compounds).

Before casting, metallic inserts 10 and 11 positioned.

Then the concrete composition is poured into the mold from the shell 9 , supported by the imprint 6 is formed, and then the concrete is vibrated in the liquid state by means of a vibrating needle, which is suitable for this purpose.

Because the shell 9 the form corresponding to the shape of the tool to be made forms, there are no other form elements, and consequently there is no later step of molding.

Then you leave Cure the concrete under the following conditions: preservation while 28 days in a constant temperature environment (≈21 ° C) and constant Moisture level (about 95%) by the air exposed surfaces of the fresh concrete is protected from drying out.

It become test bars made of the same concrete under identical conditions to calculate the mechanical properties.

you notes that the shrinkage after 30 days for the three concrete compositions in the order of magnitude of 0.05 mm / m.

• – Druckfestigkeit σ_max.c : bei Probestäben mit einem Durchmesser von 110 mm und einer Länge von 220 mm;
• – Zugfestigkeit σ_max.t1 : durch Biegeversuche (von der "Dreipunkt"-Art) mit Zwangsverschiebung an Probestäben mit den Abmessungen: 70 × 70 × 280 mm;
• – Zugfestigkeit σ_max.t2 : durch Biegeversuche (von der "Dreipunkt"-Art) mit Zwangskraft an voreingeschnittenen Probestäben mit den Abmessungen: 47 × 70 × 280 mm; diese Versuche werden nach einem Jahr durchgeführt.
• – Druckelastizitätsmodul E_c und Biegeelastizitätsmodul E_f.

The mechanical properties are calculated as follows:

• - compressive strength σ _max.c : for test bars with a diameter of 110 mm and a length of 220 mm;
• Tensile strength σ _max.t1 : by bending tests (of the "three-point" type) with forced displacement on test bars with the dimensions: 70 × 70 × 280 mm;
• Tensile strength σ _max.t2 : by bending tests (of the "three-point" type) with constraining force on pre-cut test bars of dimensions: 47 × 70 × 280 mm; these attempts will be after one year carried out.
• - compressive elastic modulus E _c and bending elastic modulus E _f .

The The results obtained are shown in Table IV for each concrete composition listed (see §3 below).

Table IV - Mechanical properties of the concrete of Table III

These Table represents the reinforcing effect the introduced into the concrete composition fibers.

After casting and solidification, the impression becomes 6 from the metal bowl 9 removed, stuck with the solidified concrete part 12 is connected, and you get the drawing tool, as in 4 is shown.

4 shows the connection between the concrete part 12 and the shell 9 which is ensured by the adhesive composition which crosslinked adhesive 13 and aggregates 14 contains.

The combination of chemical bonding action by the adhesive 13 is ensured, and the mechanical connection effect caused by the aggregates 14 ensures a very strong cohesion of the shell 9 and the concrete part.

The inserts and the part of the surface of the tool, which is made of concrete, are machined to obtain the desired dimensions and centerings; the shell obtained by electroforming 9 does not require any special treatment before using the tool under a deep-drawing press.

you receives Such a very powerful drawing tool that is very wear-resistant is and makes it possible produce good quality cuff plates with fast work cycles.

A full Study about the friction when pulling, and in particular the effect of the nickel as surface material of the tool, has shown that one obtains friction conditions that are virtually the same as those you use with a tool surface material made of steel and with a tool surface material made of electroformed Receives nickel; on a steel sheet that's easy with a lubricating film for the short-term Protection against corrosion is covered, the coefficient of friction became estimated at about 0.22.

The obtained drawing tools were tested on an industrial press and were satisfactory under classical drawing conditions; the Tests have shown that using the same tool several hundred thousand Stulpbleche can be produced.

Claims (16)

Method for producing a drawing tool from hydraulic concrete ( 12 ), which is suitable for producing Stulpblechen predetermined shape starting from sheet metal cutouts, wherein the surface of the tool which is intended to come into contact with the sheet metal cutout to be drawn, at least partially from a metal shell ( 9 ), method comprising the following steps: - manufacture of the metal shell ( 9 ) in such a way that it has a so-called "outside" corresponding to the predetermined shape of the cuff plate and an opposite, so-called "inside", - producing a mold for the drawing tool by 9 ) is taken as a mold bottom or mold element, wherein the inside is aligned to the interior of the mold, - casting an aggregate-containing composition in the mold for producing the concrete, - solidification of the composition, characterized in that prior to the step of casting a liquid adhesive phase and a solid one Phase-containing adhesive composition is applied to the inside, which is suitable to mechanical anchoring means ( 14 ) in the concrete. Method according to claim 1, characterized in that that the solid phase of the adhesive composition of aggregates is formed. Method according to claim 2, characterized in that that the aggregates of the adhesive composition of the same Type are like those of the concrete composition. Method according to one of the preceding claims, characterized in that the dimension of the anchoring means ( 14 ) perpendicular to the surface of the shell ( 9 ) is greater than the strength of the liquid phase ( 13 ) of the applied adhesive composition. Method according to one of the preceding claims, characterized in that for applying the adhesive composition, first the liquid phase ( 13 ) of the adhesive composition and then the anchoring agents ( 14 ) can be applied by placing them partially in the liquid phase ( 13 ). Method according to claim 5, characterized in that the anchoring means ( 14 ) are applied so that they partially from the free surface of the liquid phase ( 13 ) protrude. Method according to one of the preceding claims, characterized in that the liquid phase ( 13 ) of the adhesive composition is thermosetting under the solidification conditions of the concrete composition. Method according to one of the preceding claims, characterized characterized in that the composition for the production of concrete reinforcing fibers contains. Manufacturing method according to one of the preceding claims, characterized in that the shell ( 9 ) is produced by electroplating. A method according to claim 9, characterized in that the manufacture of the shell comprises the following steps: - producing an impression ( 6 ) with a surface ( 7 ) corresponding to the predetermined shape of the cuff plate; - if necessary, the surface ( 7 ) of the impression ( 6 ) make conductive; - covering the surface ( 7 ) or possibly the conductive surface ( 8th ) by electroplating with a metal layer until a metal shell ( 9 ) is formed; the inside of the shell ( 9 ) then corresponds to the metallic layer at the end of the galvanic coating. Method according to one of claims 9 to 10, characterized that the metal layer is based on nickel, and that the galvanic coating in a bath for galvanic coating that's mainly done Contains nickel sulfamate. Method according to one of claims 9 to 10, characterized the metal layer is based on copper. Method according to one of claims 9 to 12, characterized in that the impression ( 6 ) is made of polymeric material. Drawing tool of hydraulic concrete, whose surface, which is intended to come into contact with the sheet metal cutout to be drawn, at least partially with one with the concrete ( 12 ) connected metal shell ( 9 ) obtained by the method according to any one of the preceding claims, characterized in that the shell ( 9 ) with the concrete ( 12 ) is connected by means of an adhesive layer, wherein mechanical anchoring means ( 14 ) partly in the concrete ( 12 ) and partially inserted in the adhesive layer. Tool according to claim 14, characterized in that the mechanical anchoring means ( 14 ) Are aggregates. Tool according to claim 15, characterized that the aggregates of the same kind as those of Concrete are.