AUTOMATED METHOD TO DETERMINE COMPOSITE MATERIAL CONSTITUENT PROPERTIES

• US 20110178786A1
• Filed: 01/21/2011
• Published: 07/21/2011
• Est. Priority Date: 01/21/2010
• Status: Active Grant

• Current Assignee: Autodesk, Inc.
• Original Assignee: Firehole Technologies
• Inventors: Fertig, Ray, Robbins, Don, Nelson, Emmett
• Granted Patent: US 8,401,829 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;

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 utilized to obtain the adjusted material property.

2. The machine-readable medium of claim 1, wherein the set of user input composite material properties includes directional components of elastic modulus, shear modulus and Poisson ratio.

3. 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.

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

5. A method comprising:

entering a set of composite material properties into a computer memory;

entering a composite microstructure condition into the computer memory; and

processing the set of composite material properties and the composite microstructure condition to determine adjusted material properties of all constituents of the composite material, wherein a set of consistent fixed constituent property constraints are utilized to obtain the adjusted material properties.

6. The method of claim 5, wherein entering a set of composite material properties into a computer memory includes entering two directional components of elastic modulus that are normal to each other;

entering one shear modulus in a plane defined by the two directional components; and

entering a Poisson ration in the plane defined by the two directional components.

7. The method of claim 6, wherein entering the composite microstructure includes entering a carbon fiber/polymer matrix composite microstructure condition.

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

accept a set of user input carbon fiber/polymer matrix composite material properties, consisting of;

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 carbon fiber/polymer matrix microstructure;

determine an adjusted material properties of one or more the carbon fiber constituents, wherein a set of consistent fixed constituent property constraints are utilized to obtain the adjusted material properties; and

determine adjusted properties of one or more polymer matrix constituents, wherein the set of consistent fixed constituent property constraints are utilized to obtain the adjusted polymer matrix properties.