Laminate including aluminum sheets

Abstract

A laminate structure and method of forming is provided. The laminate structure includes a first metal sheet having a first thickness, a second metal sheet having a second thickness, and an adhesive core having an adhesive thickness. The adhesive core is disposed between and bonded to the first and second metal sheets. The first and second metal sheets are made of an aluminum based material and the adhesive core is made of an adhesive material also described as a viscoelastic adhesive material. The laminate structure is configured such that a ratio of the sum of the first and second thickness to the adhesive thickness is greater than either to one (8:1). The laminate structure including the viscoelastic adhesive core is characterized by a composite loss factor at 1,000 Hertz which is continuously greater than 0.1 within a temperature range of 25 degrees Celsius to 50 degrees Celsius.

1 . A laminate structure comprising:
 a first metal sheet having a first thickness;   a second metal sheet having a second thickness;   wherein the first and second metal sheets are made of an aluminum based material;   an adhesive core having an adhesive core thickness;   wherein the adhesive core is disposed between and bonded to the first and second metal sheets;   wherein a ratio of the sum of the first and second thickness to the adhesive core thickness is greater than eight to one (8:1);   an intermediate layer disposed between the adhesive layer and a surface of one of the first and second metal sheets;   wherein the intermediate layer passivates the surface of the one of the first and second metal sheets; and   wherein the intermediate layer includes one of titanium, zirconium, and tri-chromium oxide.   
     
     
         2 . The laminate structure of  claim 1 , wherein the adhesive core is made of one of a phenolic modified rubber material, and a polyester based material; and
 wherein the laminate structure is characterized by a composite loss factor at 1,000 Hertz which is continuously greater than 0.1 within a temperature range of 25 degrees Celsius to 50 degrees Celsius.   
     
     
         3 . The laminate structure of  claim 1 , wherein:
 the first thickness is within a range of 0.4 mm to 2.0 mm;   the second thickness is within a range of 0.4 mm to 2.0 mm; and   the adhesive core thickness is within a range of 0.013 mm to 0.076 mm.   
     
     
         4 . The laminate structure of  claim 3 , wherein the laminate structure is characterized by one of an n value of 0.1 or greater and an r value of 0.8 or greater. 
     
     
         5 . The laminate structure of  claim 3 , wherein the laminate structure is characterized by one of an adhesive strength as measured by T-peel of at least 1.75 Newtons/millimeter (N/mm), and a lap shear strength of at least 2 mega-Pascal (MPa). 
     
     
         6 . The laminate structure of  claim 1 , further comprising:
 an auxiliary layer disposed between the intermediate layer and the adhesive core;   wherein the auxiliary layer is configured as a corrosion prevention layer.   
     
     
         7 . The laminate structure of  claim 1 , further comprising:
 an isolation layer bonded to one of the first and second metal sheets such that the isolation layer forms an exterior layer of the laminate structure.   
     
     
         8 . The laminate structure of  claim 1 , wherein the metal sheets are made from one of a 5xxx series aluminum alloy and a 6xxx series aluminum alloy. 
     
     
         9 . A laminate structure comprising:
 a first metal sheet;   a second metal sheet;   wherein the first and second metal sheets are made of an aluminum based material; and   an adhesive core disposed between and bonded to the first and second metal sheets;   wherein the adhesive core is made of one of a phenolic modified rubber material, and a polyester based material;   wherein the laminate structure is characterized by a composite loss factor at 1,000 Hertz which is continuously greater than 0.1 within a temperature range of 25 degrees Celsius to 50 degrees Celsius.   
     
     
         10 . The laminate structure of  claim 9 , wherein the laminate structure is characterized by a composite loss factor which is continuously greater than 0.1 within a temperature range of 15 degrees Celsius to 70 degrees Celsius. 
     
     
         11 . The laminate structure of  claim 9 , further comprising:
 the first metal sheet having a first thickness;   the second metal sheet having a second thickness; and   the adhesive core having an adhesive core thickness;   wherein a ratio of the sum of the first and second thickness to the adhesive core thickness is greater than eight to one (8:1).   
     
     
         12 . The laminate structure of  claim 9 , further comprising:
 the adhesive core including a plurality of filler particles;   wherein the filler particles are made of an electrically conductive material and are arranged in the adhesive core such that the plurality of filler particles define an electrically conductive path between the first and second metal sheets.   
     
     
         13 . The laminate structure of  claim 12 , wherein each of the adhesive core including the plurality of filler particles, the first metal sheet, and the second metal sheet exhibit substantially the same electrical conductivity. 
     
     
         14 . The laminate structure of  claim 12 , wherein electrically conductive material is an aluminum based material. 
     
     
         15 . The laminate structure of  claim 12 , wherein the plurality of filler particles are characterized by a particle size in a range of −400 mesh and +500 mesh. 
     
     
         16 . A method of making a laminate structure, the method comprising:
 providing a first metal sheet;   providing a second metal sheet;   wherein each of the first and second metal sheets are made of an aluminum based material and include an inwardly facing surface;   applying an intermediate layer to the inwardly facing surfaces of the first and second metal sheets at a consistent thickness and coextensive with the inwardly facing surface to passivate the inwardly facing surface;   applying an adhesive core material to the inwardly facing surface of the first metal sheet at a uniform thickness and coextensive with the inwardly facing surface, such that the intermediate layer is disposed between the adhesive core material and first metal sheet;   laminating the first metal sheet to the second metal sheet such that the core material is disposed between the first and second metal sheets to form the laminate structure;   wherein the steps of applying the intermediate layer, applying the adhesive core material, and laminating the first metal sheet to the second metal sheet are performed sequentially in a continuous operation.   
     
     
         17 . The method of  claim 16 , further comprising:
 applying a deoxidation cleaner to the inwardly facing surfaces of the first and second metal sheets immediately prior to applying the intermediate layer;   wherein the steps of applying the deoxidation cleaner, applying the intermediate layer, applying the adhesive core material, and laminating the first metal sheet to the second metal sheet are performed sequentially in a continuous operation.   
     
     
         18 . The method of  claim 16 , wherein the intermediate layer includes one of titanium, zirconium, and tri-chromium oxide. 
     
     
         19 . The method of  claim 16 , wherein the adhesive core material is made of one of a phenolic modified rubber material, and a polyester based material. 
     
     
         20 . The method of  claim 16 , further comprising:
 applying the adhesive core material to the inwardly facing surface of the second metal sheet at a uniform thickness and coextensive with the inwardly facing surface, such that the intermediate layer is disposed between the adhesive core material and second metal sheet.