TRANSITION-JOINTS FOR JOINING DISSIMILAR MATERIALS
An assembly includes a first structural member made from a first material, such as aluminum, and having a first and a second flange, a second structural member having a first and a second flange and made from a second material, such as magnesium, and a third and a fourth structural member made from the first material and each having a first and second flange for contacting with the flanges of the first and second structural members so as to lock the first and second members together.
The present invention relates to transition-joints for joining structural and mechanical parts made from dissimilar materials.
BACKGROUND OF THE INVENTIONTwo issues with joining dissimilar materials are material compatibility and applicability of the joining process. More particularly, there are issues involved with joining aluminum to magnesium, to steel or to composites with known joining processes, such as fusion welding (e.g., gas metal arc welding) and solid-state welding (e.g., friction stir welding). These include metallurgical incompatibility, which results in uncontrolled cracking in welds and/or formation of brittle intermetallics; drastic differences in electromotive potential, which may lead to galvanic corrosion in the presence of salts and/or moisture; and incompatibility in the coefficient of thermal expansion, which could cause formation of intense residual stresses at joints and lead to failure under certain loading conditions, such as stress corrosion.
SUMMARY OF THE INVENTIONThe invention covers a transition-joint that can be used to join different materials by conventional processes that are commonly used to join the individual materials to themselves, but which cannot always be joined to other materials. The new transition-joint affords more flexibility in the design of the transitions, so the individual materials (e.g., steel and aluminum) can be joined welded and/or bolted through slip-type joints that more readily accommodate variations in the dimensional tolerances of parts, are easier to control and can result in joints with superior mechanical properties (e.g., fatigue and strength). The new transition-joints also allow the option of fabrication of the joint away from the structures in which they will be used and the option of fabrication of the joint as party of subassemblies later to be incorporated, through welding or bolting, into a larger structure.
In one embodiment, the present invention provides an assembly comprising a first structural member made from a first material, said first structural member having a flange, a second structural member made from a second material, said second structural member having a flange, a third structural member made from the first material, said third structural member having at a first flange and a second flange, wherein the flange of the first structural member contacts the first flange of the third structural member and the flange of the second structural member contacts the second flange of the third structural member, so as to lock the first member and second member together; and wherein the first structural member and the third structural member are joined directly to one another.
In another embodiment, the present invention provides an assembly, comprising a first structural member made from a first material, said first structural member having a first flange and a second flange, a second structural member made from a second material, said second structural member having a first flange and a second flange, a third structural member made from the first material, said third structural member having at a first flange and a second flange, a fourth structural member made from the first material, said fourth structural member having at a first flange and a second flange; wherein the first flange of the first structural member contacts the first flange of the third structural member, the second flange of the first structural member contacts the first flange of the fourth structural member, the first flange of the second structural member contacts the second flange of the third structural member, and the second flange of the second structural member contacts the second flange of the fourth structural member, so as to lock the first member and second member together; and wherein the first structural member and the third structural member are joined directly to one another and the first structural member and the fourth structural member are joined directly to one another.
The structural members of these assemblies that are made of the same or similar materials may be joined directly to one another by any welding process known in the art, including fusion, buried arc, laser beam or gas metal buried welding. In a further embodiment, the assemblies can further comprise one or more adhesives joining at least two structural members to one another. The assemblies can also further comprise one or more fasteners, including bolts or rivets, joining at least two structural members to one another.
The invention further provides methods for assembling the transition-joints disclosed herein.
Further features and advantages of the invention will appear more clearly on a reading of the detailed description of the embodiments of the invention, which is given below by way of example only with reference to the accompanying drawings.
For a better understanding of the present invention, reference is made to the following detailed description of the embodiments considered in conjunction with the accompanying drawings, in which:
Referring to
Referring to
Another embodiment of the present invention is illustrated in
It should be understood that the embodiments described herein are merely exemplary and that a person skilled in the art may make many variations and modifications without departing from the spirit and scope of the invention. Accordingly, all such variations and modifications are intended to be included within the scope of the embodiments described herein as defined in the appended claims.
Claims
1. An assembly, comprising:
- a first structural member made from a first material, the first structural member having a first flange and a second flange;
- a second structural member made from a second material, the second structural member having a first flange and a second flange;
- a third structural member made from the first material, the third structural member having a first flange and a second flange;
- a fourth structural member made from the first material, the fourth structural member having a first flange and a second flange;
- wherein the first flange of the first structural member contacts the first flange of the third structural member, the second flange of the first structural member contacts the first flange of the fourth structural member, the first flange of the second structural member contacts the second flange of the third structural member, and the second flange of the second structural member contacts the second flange of the fourth structural member; and
- wherein the first structural member and the third structural member are joined directly to one another at a point of contact between the first structural member and the first flange of the third structural member, and the first structural member and the fourth structural member are joined directly to one another at a point of contact between the first structural member and the first flange of the fourth structural member, so as to lock the first structural member and second structural member together.
2. The assembly of claim 1, wherein the first structural member and the third structural member are joined directly to one another by welding at a point of contact between the first structural member and the first flange of the third structural member and the first structural member and the fourth structural member are joined directly to one another by welding at a point of contact between the first structural member and the first flange of the fourth structural member.
3. The assembly of claim 1, wherein the first structural member is a top locking plate or “T” extrusion.
4. The assembly of claim 1, wherein the second structural member has a “T” shape when viewed on cross-section.
5. The assembly of claim 2, wherein the point of contact between the first structural member and third structural member comprises a partial swivel type joint.
6. The assembly of claim 1 wherein the first and second structural members contact each other.
7. The assembly of claim 6, wherein the third and fourth structural members substantially conform to the outer contour of the first structural member and second structural member when the assembly is viewed on cross-section.
8. The assembly of claim 1, further comprising one or more sealants or adhesives joining at least two structural members to one another.
9. The assembly of claim 1, further comprising one or more fasteners joining at least two structural members to one another.
10. The assembly of claim 9, wherein the one or more fasteners comprise bolts or rivets.
11. A method comprising the steps of:
- providing a first structural member made from a first material, said first structural member having a first flange and a second flange;
- providing a second structural member made from a second material, said second structural member having a first flange and a second flange;
- providing a third structural member made from the first material, said third structural member having at a first flange and a second flange;
- providing a fourth structural member made from the first material, said fourth structural member having at a first flange and a second flange;
- contacting the first flange of the first structural member with the first flange of the third structural member, the second flange of the first structural member with the first flange of the fourth structural member, the first flange of the second structural member with the second flange of the third structural member, and the second flange of the second structural member with the second flange of the fourth structural member; and
- directly joining the first structural member and the third structural member to one another at a point of contact between the first structural member and the first flange of the third structural member; and
- directly joining the first structural member and the fourth structural member to one another at a point of contact between the first structural member and the first flange of the fourth structural member,
- thereby locking the first structural member and second structural member together.
Type: Application
Filed: Mar 10, 2010
Publication Date: Sep 15, 2011
Inventors: Israel Stol (Pittsburgh, PA), Miloslav Novak (Glenshaw, PA), Jerri McMichael (New Kensington, PA), John W. Cobes, JR. (Lower Burrell, PA), Eric Bogan (Cabot, PA)
Application Number: 12/721,376
International Classification: E04B 1/38 (20060101);