Microlattice damping material and method for repeatable energy absorption
Described is a micro-lattice damping material and a method for repeatable energy absorption. The micro-lattice damping material is a cellular material formed of a three-dimensional interconnected network of hollow tubes. This material is operable to provide high damping, specifically acoustic, vibration or shock damping, by utilizing the energy absorption mechanism of hollow tube buckling, which is rendered repeatable by the micro-lattice architecture.
1. A damping material, comprising:
a micro-lattice formed of a three-dimensional interconnected network of hollow tubes;
wherein the hollow tubes are formed of a material having a relatively density in a range of 0.00001 to 0.0005 in relation to the theoretical density of the material and have a wall thickness and a diameter, such that a wall thickness to diameter ratio is on the order of ε y , wherein ε y denotes a yield strain material property of the material forming the hollow tubes; and
wherein the damping ability is provided by elastic buckling of the hollow tubes and/or nodes where the tubes intersect upon receiving a load, whereby upon removal of that load, the micro-lattice substantially recovers its original shape.
2. The damping material as set forth in claim 1 , wherein the hollow tubes are formed of a material selected from a group consisting of metal, ceramic, and a polymer.
3. The damping material as set forth in claim 1 , further comprising a constraining layer attached to the micro-lattice, with the micro-lattice being attached with an object to be dampened.
4. The damping material as set forth in claim 1 , wherein the micro-lattice includes a damping coefficient (tan δ) that is greater than 0.05.
5. The damping material as set forth in claim 1 , wherein the micro-lattice has a density smaller than 0.1 g/cm 3 .
6. The damping material as set forth in claim 1 , further comprising two materials, with the micro-lattice being partially compressed between the two materials such that the micro-lattice is pre-loaded with strain.
7. The damping material as set forth in claim 6 , wherein the micro-lattice is preloaded to strains between 3% and 50%.
8. The damping material as set forth in claim 1 , wherein the micro-lattice has a density of 10 mg/cm 3 or less.
9. The damping material as set forth in claim 1 , wherein the micro-lattice operable for damping at temperatures greater than 300 degrees Celsius, lower than negative 100 degrees Celsius, or over temperature range exceeding 200 degrees Celsius.
10. The damping material as set forth in claim 1 , wherein the micro-lattice is attached to one or more face sheets.
11. The damping material as set forth in claim 1 ,
wherein the diameter is between 10 and 1000 microns; and
wherein the wall thickness is between 0.01 and 2 microns.