Patent Application
20130209163
The present invention refers to a method for joining components through mechanical adhesion without the use of inserts and without modifying the mechanical properties of the components to be joined. It also refers to a mechanical adhesion joint for joining components formed by this method, this joint being applied on the surface of the components without damaging or altering the mechanical properties and the structural characteristics of these components.
Different forms of joining or bonding two components or parts are known in the state of the art, namely: chemical bonding, electrostatics, interdiffusion, mechanical adhesion, collage, various encasements, by means of fixing elements, etc.
However, many of these require specific machining, holes or modifications in the structures or surfaces of the components and for certain cases this interference is not possible or desirable, especially in joining parts made of composite or thermoplastic materials whose mechanical structures undergo profound alterations when subjected to fusion, heating or reaction to certain chemical products.
In this sense, one solution found consists of positioning inserts between the parts to be bonded so that they anchor the parts. In the same way, there are situations in which the placement of these inserts is not possible or desirable by virtue of the construction material of the parts to be bonded, the precision of the joint which requires an intact surface or other design demands.
As an example we may cite document US 2009/0190997 which describes a joint for bonding a metallic part to a part made of composite material with reinforcement that is inserted between composite material laminates. In this joint, a metallic part is bonded to a composite part in an engagement region of varied size depending on the structural forces to which the parts will be subjected. Multiple attachment projections are disposed projecting from the metallic part inwardly of the composite part, these attachment projections are made of the same metallic material as the metallic part or another different metal, but always a metallic material. The distribution of the attachment projections is not uniform along the engagement region, the largest concentration being in the portions in which the tension between the composite material laminates is greater, generally near the ends of the engagement region. Accordingly, for joining parts made of composite material to metallic parts, this document from the state of the art teaches the insertion of metallic projections which are fastened on the metallic part and inserted into the composite part in order to anchor or join these two parts, the regions in which this bond will undergo greatest tension being privileged with a larger number of metallic projections. Therefore, it is necessary to study the tensions and forces to which these parts will be subjected before joining them. Nothing is taught in this document about the joining of two or more parts made of composite, with the presence of metallic parts or components. Additionally, it is necessary for the metallic projections to be formed on the metallic part so that anchorage occurs, that is, the metallic projections serve as metallic inserts for joining the parts.
Document US 2010/0068464 describes a method for preparing a metallic component to be bonded to another composite or thermoplastic material component, this method comprises the formation or insertion of projections into a bond region of the component such that these projections are inserted into the material of the other component to be bonded. This method can be applied for joining components of an aircraft. More specifically, this document describes the disposition of projections on a bonding area formed on a metallic insert. This insert is inserted into the part to be bonded and its projections penetrate the second part to be bonded. In another embodiment, the web of projects is done using laser sintering which melts the metallic powder bed of the surface of the component in the desired matrix forming line by line of the projections. These projections can also be done one by one using the laser sintering method and, moreover, can be done by laser sintering on the two sides of a metallic plate which will serve as bonding insert of the two components desired. Besides requiring much time to form the projections, the use of laser sintering significantly increases the costs of this method of joining parts or components.
Document WO 2004/028731 refers to a method to modify the structure of a workpiece. In this case, a workpiece, made of steel, receives electron beams so that the surface material melts and hardens again forming small projections on the surface of the workpiece. The size of these projections depends on the quantity of beams inserted into the same region of the workpiece and these projections, made of the very material of the surface of the part made of steel, act as anchorage or bonding element which is inserted into the layers of the composite material which will be bonded to this workpiece. Although it creates projections capable of safely bonding a part made of steel to another made of composite material, modifying the surface of the workpiece, that is, of the part made of steel is not always possible and desirable, since its mechanical properties are also modified.
Accordingly, the technologies and procedures already known in the state of the art mostly use metallic inserts in the parts to be bonded, which requires care in terms of the difference of thermal expansion/contraction during the use and oxidation, thus being limited to using parts with galvanic similarities.
There is also a technique known as “Co-bonding” in which a part, generally made of composite, is disposed on another part also made of composite and subjected to the curing process. By curing, the resin of one part bonds to the other part, whereby chemical bonding occurs. Controlling this chemical adhesion, however, is rather complex. There is oftentimes the need to add a light layer of a specific material (polyester with epoxy, for example) on the surface of one of the parts to render it slightly wrinkled (lightly texturized) and thereby improving the anchorage of the parts through this texturization. In this case, it may also be necessary to complement the bonding by inserting rivets to guarantee fastening.
The objective of the present invention is to provide a method for joining components through mechanical adhesion without the use of inserts and without modifying the mechanical properties of the components to be joined.
It is also an objective of this invention to provide a mechanical adhesion joint for joining components, this joint being applied on the surface of the components without damaging or altering the mechanical properties and structural characteristics of these components.
The object of the invention is a method for joining components through mechanical adhesion comprising the following stages:
a) curing a resin laminate on a surface of a first component imprinting a texture portion upon the resin laminate;
b) positioning an adhesive material laminate on the texture portion;
c) positioning a second component on the adhesive material laminate; and
d) curing the adhesive material laminate and penetration of the adhesive material laminate on the texture portion.
Another object of this invention is a mechanical adhesion joint for joining components, comprising an anchorage formed by a texture portion disposed on a first component and permeated by an adhesive material laminate contained in a second component, a texture portion comprising a locking profile.
The present invention will now be described in greater detail based on an example of execution represented in the drawings. The drawings show:
FIGS. 1A to 1F—illustrate the stages of the method for joining components through mechanical adhesion, which is the object of this invention;
FIGS. 2A to 2C—illustrate a first and second arrangements of the mechanical adhesion joint for joining components, which is the object of the present invention; and
FIGS. 3A and 3B—illustrate a third arrangement of the mechanical adhesion joint for joining components, which is the object of the present invention.
According to a preferred embodiment and as can be seen in
a) curing a resin laminate 1 on a surface 10 of a first component 11 imprinting a texture portion 30 upon the resin laminate 1;
b) positioning an adhesive material laminate 2 on the texture portion 30;
c) positioning a second component 12 on the adhesive material laminate 2; and
d) curing the adhesive material laminate 2 and penetration of the adhesive material laminate 2 into the texture portion 30.
As can be seen in
The resin laminate 1 will cover a certain portion of the surface 10 of this first component 11, in accordance with the desirably safe and satisfactory bonding of the components involved.
After the disposition of the resin laminate 1 surface 10 of this first component 11, a texturized mold 50 is positioned on this resin laminate 1. This texturized mold 50 comprises profiles 51 which will be imprinted upon the resin laminate 1.
Once the texturized mold 50 is positioned, the first curing stage is carried out using a vacuum bag 60 which encompasses the texturized mold 50 positioned on the resin laminate 1 and the first component 11 which received the resin laminate 1, as can be seen in
At the end of the first curing stage, the texturized mold 50 is withdrawn and the texture portion 30 is imprinted upon the resin laminate 1 based on the profiles 51 of the texturized mold 50, that is, the texture portion 30 imprinted upon the resin laminate 1 will present a locking profile 31 identical to the profile 51 of the texturized mold 50 used, as illustrated in
Next, as illustrated in
The adhesive material laminate 2 and the second component 12 not yet cured are disposed on the texture portion 30 on the first component 11, both already cured.
Thus, a second curing stage also occurs by way of the vacuum bag 60, this time encompassing the adhesive material laminate 2, the second component 12, not yet cured, the resin laminate 1 with the texture portion 30 and the first component 11 already cured, as illustrated in
At the end of the second curing stage,
The present invention also refers to a mechanical adhesion joint 20 for joining components, formed according to the method for joining components through mechanical adhesion described above.
As illustrated in
Accordingly, the joint 20 comprises an anchorage 40 which consists of the adhesive material laminate 2 disposed on the second component 12 permeated on the texture portion 30 disposed on the first component 11.
This anchorage 40 of the joint 20 is primarily responsible for bonding the first component 11 with the second component 12, although there is also the chemical gluing of the adhesive material laminate 2 on the resin laminate 1. The anchorage 40 of the joint 20 is primarily responsible for bonding the first component 11 with the second component 12 because, as illustrated in
This joint 20, formed according to the method described above, can be applied when the first component 11 and the second component 12 are made of composite material, when the first component 11 and the second component 12 are made of thermoplastic material and when the first component 11 and the second component 12 are made of polymer.
Additionally, the joint 20 may also be used if one of the components 11, 12 are made of composite material and the other component 11, 12 made of thermoplastic material, when one of the components 11, 12 is made of composite material and the other component 11, 12 is made of polymer material, when one of the components 11, 12 is made of thermoplastic material and the other component 11, 12 is made of polymer material and when one of the components 11, 12 is made of metallic material and the other component 11, 12 is made of composite material.
Accordingly, the method for joining components through mechanical adhesion and the mechanical adhesion joint for joining components that are the objects of this invention present a series of advantages over the methods and forms of joining parts already known in the state of the art, particularly the use of low-cost texturized molds, the fast and practical way to form the texture portion 30 on the first component 11, to increase the interface area for the chemical gluing which assists the mechanical anchorage 40, to resist traction and shearing forces and to define the geometries of the locking profiles 31 of the texture portion 30 in accordance with the need and request for loads to which the joint 20 will be subjected.
It should be emphasized that the joint 20 is fundamentally mechanical, but can be used in combination with other types of joints such as, for example, chemical bonding, by electrostatic attraction, interdiffusion, among others.
Having described an example of a preferred embodiment, it should be understood that the scope of the present invention encompasses other possible variations, being limited only by the content of the accompanying claims, potential equivalents being included therein.
| Number | Date | Country | Kind |
|---|---|---|---|
| PI 1105343-7 | Dec 2011 | BR | national |
