Structural sandwich plate members

Abstract

A structural sandwich plate member is provided with at least one interlayer to improve ballistics and/or blast resistance. The interlayer may be a solid or perforated metal plate, a metal mesh, hard ceramic or high tensile strength fabric. The interlayer may be corrugated.

1 . A structural sandwich plate member comprising: 
 first and second outer plates;    a core of plastics or polymer material bonded to said outer plates with sufficient strength to transfer shear forces therebetween; and    at least one interlayer within the core, said interlayer being generally parallel to the outer plates and having a higher tensile strength than the core material.    
   
   
       2 . A structural sandwich plate member according to  claim 1  wherein said interlayer comprises a metal, e.g. steel, stainless steel or aluminium, layer.  
   
   
       3 . A structural sandwich plate member according to  claim 2  wherein said interlayer has a thickness in the range of from 50% to 150% of the thickness of one of said outer plates.  
   
   
       4 . A structural sandwich plate member according to  claim 1  wherein said interlayer-comprises metal (e.g. steel, stainless steel or aluminium) mesh.  
   
   
       5 . A structural sandwich plate member according to  claim 4  wherein said metal mesh is formed of expanded metal.  
   
   
       6 . A structural sandwich plate member according to  claim 1  wherein said interlayer comprises a high tensile strength fabric.  
   
   
       7 . A structural sandwich plate member according to  claim 1  wherein said interlayer comprises a hard ceramic plate.  
   
   
       8 . A structural sandwich plate member according to  claim 1  wherein said interlayer is corrugated, or dimpled or wave-formed.  
   
   
       9 . A structural sandwich plate member according to  claim 1  comprising a plurality of interlayers.  
   
   
       10 . A structural sandwich plate member according to  claim 1  wherein said interlayer is perforated.  
   
   
       11 . A structural sandwich plate member according to  claim 1  wherein said interlayer does not extend over the whole area of said plate member.  
   
   
       12 . A structural sandwich plate member according to  claim 1  wherein said outer plates are made of metal.  
   
   
       13 . A structural sandwich plate member according to  claim 1  wherein said outer plates have a thickness greater than or equal to 3 mm  
   
   
       14 . A structural sandwich plate member according to any one of the  claim 1  wherein said core is made of a compact material.  
   
   
       15 . A structural sandwich plate member according to  claim 1  wherein said core has a thickness greater than or equal to 15 mm.  
   
   
       16 . A method of manufacturing a structural sandwich plate member comprising the steps of: 
 providing first and second outer plates in a spaced-apart relationship with at least one interlayer located therebetween and spaced from each of said outer metal plates;    injecting uncured plastics or polymer material to fill the space defined between said outerplates and either side of said interlayer; and    allowing said plastics or polymer material to cure to bond said outer plates together with sufficient strength to transfer shear forces therebetween;    wherein said interlayer has a higher tensile strength than the cured plastics or polymer material.    
   
   
       17 . A method according to  claim 16  wherein said step of injecting is carried out from both sides of the plate, either simultaneously or in two stages.  
   
   
       18 . A method according to  claim 16  comprising the additional step of coating or impregnating the interlayer with plastics or polymer material prior to insertion into the cavity between the outer metal plates.