AUTOMATED METHOD TO DETERMINE COMPOSITE MATERIAL CONSTITUENT PROPERTIES

• US 20130218540A1
• Filed: 03/18/2013
• Published: 08/22/2013
• Est. Priority Date: 01/21/2010
• Status: Active Grant

• Current Assignee: Autodesk, Inc.
• Original Assignee: Firehole Technologies
• Inventors: Fertig, Ray, Nelson, Emmett, Robbins, Don
• Granted Patent: US 8,868,385 B2
• Time in Patent Office: Days
• US Class Current: 703/2
• CPC Class Codes: G06F 2113/24 Sheet material
• CPC Class Codes: G06F 2113/26 Composites
• CPC Class Codes: G06F 30/23 using finite element methods [FEM] or finite difference methods [FDM]

Abstract

A method of determining in situ composite material constituent properties is provided. In one example computer software is provided that automatically determines adjusted material properties or in situ properties of each constituent of a composite material. Methods shown ensure that a finite element model will consistently predict material behavior not just at one desired stress/strain state, but in all simulated states.

Claims

1. A machine-readable medium with instructions stored thereon, the instructions when executed operable to:

accept a set of user input composite material properties, including;

a composite modulus in a first direction;

a composite modulus in a second direction normal to the first direction;

a composite shear modulus in a plane that includes the first direction and the second direction;

a composite Poisson ratio in a plane that includes the first direction and the second direction;

accept a user input composite microstructure; and

automatically compute adjusted material properties of all constituents of the composite material, wherein a set of consistent fixed constituent property constraints are utilised to obtain the adjusted material property.

2. The machine-readable medium of claim 1, wherein the set of user input composite material properties includes at least one directional component of a thermal expansion coefficient.

3. The machine-readable medium of claim 1, wherein the set of user input composite material properties includes an additional composite modulus in a third direction normal to the first direction and the second direction.

4. The machine-readable medium of claim 3, wherein the set of user input composite material properties includes an additional composite shear modulus in a plane that includes the first direction and the third direction.

5. The machine-readable medium of claim 4, wherein the set of user input composite material properties includes an additional composite shear modulus in a plane that includes the second direction and the third direction.

6. The machine-readable medium of claim 3, wherein the set of user input composite material properties includes an additional composite Poisson ratio in a plane that includes the first direction and the third direction.

7. The machine-readable medium of claim 6, wherein the set of user input composite material properties includes an additional composite Poisson ratio in a plane that includes the second direction and the third direction.

8. The machine-readable medium of claim 2, wherein the set of user input composite material properties includes two directional components of a thermal expansion coefficient in directions that are normal to one another.

9. The machine-readable medium of claim 2, wherein the set of user input composite material properties includes thee directional components of a thermal expansion coefficient in directions that are normal to one another.

10. The machine-readable medium of claim 1, wherein accepting a user input composite microstructure includes accepting a carbon fiber/polymer matrix composite microstructure condition.

11. The machine-readable medium of claim 10, wherein accepting a user input composite microstructure includes accepting a woven carbon fiber/polymer matrix composite microstructure condition.

12. A method comprising:

entering a set of carbon fiber/polymer matrix composite material properties into a computer memory, including;

a composite modulus in a first direction;

a composite modulus in a second direction normal to the first direction;

a composite shear modulus in a plane that includes the first direction and the second direction;

a composite Poisson ratio in a plane that includes the first direction and the second direction;

entering a carbon fiber/polymer matrix composite microstructure into the computer;

processing the set of carbon fiber/polymer matrix composite material properties and the carbon fiber/polymer matrix composite microstructure to determine adjusted material properties of all constituents of the composite material, wherein a set of fixed constituent property constraints are utilised to obtain the adjusted material properties.

13. The method of claim 12, wherein entering the set of carbon fiber/polymer matrix composite material properties includes entering at least one directional component of a thermal expansion coefficient.

14. The method of claim 12, wherein entering the set of carbon fiber/polymer matrix composite material properties includes entering an additional composite modulus in a third direction normal to the first direction and the second direction.

15. The method of claim 14, wherein entering the set of carbon fiber/polymer matrix composite material properties includes entering an additional composite shear modulus in a plane that includes the first direction and the third direction.

16. The method of claim 15, wherein entering the set of carbon fiber/polymer matrix composite material properties includes entering an additional composite shear modulus in a plane that includes the second direction and the third direction.

17. The method of claim 14, wherein entering the set of carbon fiber/polymer matrix composite material properties includes entering an additional composite Poisson ratio in a plane that includes the first direction and the third direction.

18. The method of claim 17, wherein entering the set of carbon fiber/polymer matrix composite material properties includes entering an additional composite Poisson ratio in a plane that includes the second direction and the third direction.

19. The method of claim 13, wherein entering the set of carbon fiber/polymer matrix composite material properties includes entering two directional components of a thermal expansion coefficient in directions that are normal to one another.

20. The method of claim 13, wherein entering the set of carbon fiber/polymer matrix composite material properties includes entering thee directional components of a thermal expansion coefficient in directions that are normal to one another.