Multifunctional nano-skin articles and methods

• US 8,479,880 B2
• Filed: 09/15/2010
• Issued: 07/09/2013
• Est. Priority Date: 09/15/2010
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Mathur, Gopal P.
• Primary Examiner(s): San Martin, Edgardo
• Application Number:
  US12/882,600
• Publication Number:
  US 20120064285A1
• Time in Patent Office: 1,028 Days
• Field of Search: 181/296, 181/290, 181/292, 181/294, 181/288, 181/207, 181/208, 181/210, 181/284, 244/119, 244/1.N, 244/117.R, 244/123.13, 244/121
• US Class Current: 181/296
• CPC Class Codes: B32B 2264/108 Carbon, e.g. graphite particles
• CPC Class Codes: B32B 2307/10 having particular acoustical properties
• CPC Class Codes: B32B 2307/102 Insulating
• CPC Class Codes: B32B 2307/56 Damping, energy absorption
• CPC Class Codes: B32B 25/04 comprising rubber as the main or only constituent of a layer, which is next to another layer of the same or of a different material next to a layer of a particular substance B32B9/043; next to a bituminous or tarry layer B32B11/044; next to a water setting substance layer B32B13/042; next to a metal layer B32B15/06; next to a glass layer B32B17/063; next to a layer formed of natural mineral fibres or particles B32B19/043; next to a wood layer B32B21/045; next to a cellulosic plastic layer B32B23/046
• CPC Class Codes: B32B 25/14 comprising synthetic rubber copolymers B32B25/18 and B32B25/20 take precedence
• CPC Class Codes: B32B 25/20 comprising silicone rubber
• CPC Class Codes: B32B 2605/18 Aircraft blades, propellers B32B2603/00
• CPC Class Codes: B32B 27/06 as the main or only constituent of a layer, which is next to another layer of the same or of a different material next to a layer of a particular substance B32B9/045; next to a bituminous or tarry layer B32B11/046; next to a water setting substance layer B32B13/12; next to a metal layer B32B15/08; next to a glass layer B32B17/10; next to a layer formed of natural mineral fibres or particles B32B19/045; next to a wood layer B32B21/08; next to a cellulosic plastic layer B32B23/08; next to a natural or synthetic rubber layer B32B25/08
• CPC Class Codes: B32B 27/20 using fillers, pigments, thixotroping agents
• CPC Class Codes: B32B 3/12 characterised by a layer of regularly- arranged cells, e.g. a honeycomb structure
• CPC Class Codes: B32B 3/28 characterised by a layer comprising a deformed thin sheet , i.e. the layer having its entire thickness deformed out of the plane, e.g. corrugated, crumpled B32B29/08 takes precedence
• CPC Class Codes: B64C 1/12 Construction or attachment of skin panels
• CPC Class Codes: B64C 2001/0072 from composite materials
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C09D 5/24 Electrically-conducting paints conductive materials H01B1/00
• CPC Class Codes: C09D 7/61 inorganic
• CPC Class Codes: C09D 7/70 characterised by shape, e.g. fibres, flakes or microspheres
• CPC Class Codes: Y02T 50/40 Weight reduction
• CPC Class Codes: Y10T 428/24149 Honeycomb-like
• CPC Class Codes: Y10T 428/24994 : Fiber embedded in or on the surface of a polymeric matrix

Abstract

Methods for vibration and acoustic abatement. The methods comprise providing a substrate with a composite layer deposited thereon, the substrate receiving a vibration energy sufficient to provide at least one bending wave therein, and converting at least a portion of the vibration energy sufficient to cause the at least one bending wave to at least one shear wave in at least a portion of the composite layer. The composite layer comprises an elastomeric polymer matrix comprising carbon nano tubes dispersed or distributed therein. Articles with the composite layer comprising carbon nano tubes disposed thereon are also disclosed and described.

Claims

1. A method comprising:

providing a substrate comprising a composite layer, the substrate being formed to provide at least one bending wave therein in response to receiving a vibration energy sufficient to cause the at least one bending wave in the substrate; and

converting at least a portion of the vibration energy sufficient to cause the at least one bending wave to at least one shear wave in a portion of the composite layer;

wherein the composite layer comprises an elastomeric polymer matrix comprising carbon nano tubes dispersed or distributed therein in an amount capable of converting at least a portion of the bending wave of the substrate to the at least one shear wave of the composite layer.

2. The method of claim 1, further comprising attenuating acoustic radiation from the substrate.

3. The method of claim 1, wherein the composite layer further provides viscoelastic dissipation of vibration energy.

4. The method of claim 1, wherein the composite layer further provides electrical and/or thermal conductivity.

5. The method of claim 1, wherein the carbon nano tubes are preferentially oriented in the composite layer.

6. The method of claim 1, wherein the composite layer comprises a honey-combed structure sandwiched between opposing face sheets, the elastomeric polymer matrix adjacent one of the face sheets, and the substrate adjacent the corresponding opposing face sheet.

7. The method of claim 1, wherein the at least one bending wave is a result of energy from supersonic velocity and at least a portion of the at least one shear wave is of subsonic velocity.

8. A method of attenuating acoustic vibration energy in an aerospace vehicle, the method comprising:

providing a fuselage comprising a composite layer deposited thereon, the fuselage being formed to provide at least one bending wave therein in response to receiving a vibration energy sufficient to cause the at least one bending wave in the fuselage; and

converting at least a portion of the vibration energy sufficient to cause the at least one bending wave to at least one shear wave in a portion of the composite layer;

wherein the composite layer comprises an elastomeric polymer matrix comprising an amount of carbon nano tubes sufficient to convert the at the least one bending wave from the fuselage into the at least one shear wave in the composite.

9. The method of claim 8, wherein the composite layer further provides viscoelastic dissipation of vibration energy in the composite layer.

10. The method of claim 8, wherein the composite layer further provides electrical and/or thermal conductivity to the composite layer.

11. The method of claim 8, wherein the carbon nano tubes are preferentially oriented in the elastomeric polymer matrix.

12. The method of claim 8, wherein the composite the composite layer comprises a honey-combed structure sandwiched between opposing face sheets, the elastomeric polymer matrix adjacent one of the face sheets, and the fuselage adjacent the corresponding opposing face sheet.

13. The method of claim 8, wherein the at least one bending wave is of supersonic velocity and at least some of the at least one shear wave is of subsonic velocity.

14. An article comprising:

a composite layer comprising;

a substrate;

a first layer disposed on a surface of the substrate, the first layer comprising an elastomeric polymer or elastomeric pre-polymer and a predetermined amount of carbon nano tubes dispersed or distributed therein, the composite comprising an amount of the carbon nano tubes sufficient to receive vibration energy causing at least one bending wave in the substrate and to convert the vibration energy sufficient to cause the at least one bending wave to at least one shear wave in a portion of the composite.

15. The article of claim 14, further comprising a honey-combed structure sandwiched between opposing face sheets, the elastomeric polymer matrix adjacent one of the face sheets, and the substrate adjacent the corresponding opposing face sheet.

16. The article of claim 14, wherein the elastomeric polymer or elastomeric pre-polymer is at least one of a polysilicone, a fluorocarbon elastomer, a polyurethane, a blend of thermoplastic and thermoset rubber, a styrene-butadiene polymer, an ionomer, and a thermoset rubber.

17. The article of claim 16, wherein the amount of carbon nano tubes is about 3 wt % to about 5 wt %.

18. The article of claim 16, wherein the carbon nano tubes are preferentially oriented relative to the surface of the substrate.

19. The article of claim 14, wherein the substrate forms at least a part of an aerospace vehicle.