Manufacture of Lattice Truss Structures from Monolithic Materials

Abstract

Methods and systems to manufacture lattice-based sandwich structures from monolithic material eliminate the bonding process which is conventionally used to join lattice-based truss cores to facesheets to form sandwich structures. The bonded interface is a key mode of failure for sandwich structures which are subjected to shear or bending loads because the nodes transfer forces from the facesheets to the core members while the topology for a given core relative density dictates the load carrying capacity (assuming adequate node-bond strength exists). In one aspect, a core and related structures provide very low density, good crush resistance and high in-plane shear resistance. Another aspect of the truss structures may include sandwich panel cores and lattice truss topology that may be designed to efficiently support panel bending loads while maintaining an open topology that facilitates multifunctional applications.

1 . A monolithic lattice truss-based structure comprising:
 a plurality of truss unit portions comprising two facesheet portions and a plurality of rows of legs between and connecting said facesheet portions, wherein said truss unit portions have the same metallurgical and microstructural properties.   
     
     
         2 . The structure of  claim 1 , wherein the metallurgical and microstructural properties of said facesheet portions and said legs are the same. 
     
     
         3 . The structure of  claim 1 , wherein said truss unit portions have nodes, wherein said nodes have the same metallurgical and microstructural properties as said truss unit portions. 
     
     
         4 . The structure of  claim 2 , wherein said truss unit portions have nodes, wherein said nodes have the same metallurgical and microstructural properties as said truss unit portions and said facesheet portions. 
     
     
         5 . The structure of  claim 1 , wherein said truss unit portions do not include any bonding, adhesives, diffusion bonding, brazing, soldering, or resistance/electron/laser welding or coupling as joining mechanisms. 
     
     
         6 . The structure of  claim 1 , wherein said truss unit portions comprise at least one select material of any one of ceramic, polymer, metal, metal alloy, or composites thereof. 
     
     
         7 . The structure of  claim 1 , wherein said truss unit portions have a geometrical shape of any one of: tetrahedral, pyramidal, Kagome, cone, frustum, or combinations thereof. 
     
     
         8 . The structure of  claim 1 , wherein said truss unit portions comprise an array of truss unit portions. 
     
     
         9 . The structure of  claim 2 , wherein said truss unit portions and said facesheet portions comprise sandwich structures. 
     
     
         10 . The structure of  claim 1 , wherein said truss unit portions have varying relative density. 
     
     
         11 . The structure of  claim 9 , wherein said sandwich structures provide blast impact mitigation. 
     
     
         12 . The structure of  claim 9 , further comprising inserts and filler material disposed between said facesheet portions, wherein said sandwich structures provide projectile arresting capability. 
     
     
         13 . The structure of  claim 9 , wherein said sandwich structures are laterally in communication with one another. 
     
     
         14 . The structure of  claim 13 , wherein said communication comprises at least one of the following:
 bonding, adhesives, diffusion bonding, brazing, soldering, or resistance/electron/laser welding or coupling.