relevant scalecm - mm mm - m m - nm tunable architectural feature 3-d spatial location of truss...
TRANSCRIPT
Relevant Scale cm - mm mm - mm mm - nm
Tunable Architectural Feature
3-D spatial location of truss elements
Orientation, aspect ratio, wall thickness
Composition, microstructure
E-Beam Processing Control
Overall 3-D geometry, node properties
Strut geometry and wall thickness
Grain structure, composition
Modeling approach Macro-scale finite element analysis
Micro-scale finite element analysis
Molecular Dynamics
Lattice-based unit cell
Hollow tube lattice member
Lattice-strut microstructure
Mechanical Properties of Test Sphere (Across Different Length Scales)
Plastic collapse (solid)
Plastic buckling (hollow)
Grain structure
Crystal structure
Properties of the StrutCritical Features
• Composition• Microstructure
• Grain size• Dislocation density/distribution
• Geometry/Topology
Grain size effect on strength
Dislocation effect on strength
ORNL Sphere (e-beam processed)
Pingle S M et al. Proc. R. Soc. A doi:10.1098/rspa.2010.0329
Compressive Response for Different Strut Geometries Loaded Axially
Mechanical behavior of struts depends on:
• Material properties – strength, modulus…
• Geometry – solid or tube will change buckling behavior
• Tube – wall thickness will control buckling
b
d
c
a
e
Pingle S M et al. Proc. R. Soc. A doi:10.1098/rspa.2010.0329
Compressive Response for Different Strut Geometries Loaded at an
Incline
Mechanical behavior of struts load on an incline:
• Buckling will depend on load path
• Mechanical properties of nodes where struts connect are critical
• Tube – wall thickness will control buckling
b
c
d
a
e
Pingle S M et al. Proc. R. Soc. A doi:10.1098/rspa.2010.0329
Compressive Strength vs. Density of Lattice Materials
Properties at the Lattice Scale
Lattice materials allow for more efficient structural loading under compression
Structural efficiency of hollow stainless steel trusses under compression
sY=180MPa
Pyramidal hollow lattice truss of single crystal SS
>4X