Is it possible to represent a composite sandwich panel made of 2 carbon fiber plies (one on each side of the core) and nomex honeycomb (core) as a single MAT9OR material?

Frederic Auger
Frederic Auger New Altair Community Member
edited March 6 in Community Q&A

Hi,

 

I am a student in mechanical engineering and I want to run FEA on composite sandwich to analyze bending behaviour of certain parts.

As stated in the question, the sandwich construction is as follows:

1. Cross-ply carbon fiber lamina [0/90]

2. 4.8 mm Honeycomb Nomex

3. Cross-ply carbon fiber lamina [0/90]

Based on my preliminary research, honeycomb Nomex can be considered as an orthotropic material. 

Also, I know that cross-ply carbon fiber are orthotropic material

Therefore, I was wondering if it would be possible (and perhaps simpler) to consider the sandwich as a single 3D orthotropic material (MAT9OR)

or maybe 2D orthotropic material (MAT8) since the total thickness is very small (around 5 mm).

Furthermore, if I want to run FEA to check bending, is there any properties in the material Data card that I could potentially discard or does the software needs all the properties for such analysis?

Finally, if anyone knows good documentation on this subject, do not hesitate to send some references.

 

Thank you,

 

Frédéric Auger

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Answers

  • Adriano A. Koga
    Adriano A. Koga
    Altair Employee
    edited July 2023

    concerning material cards you would need 2, at least, one for the honeycomb core, and another to the reinforcement (Carbon fiber).

     

    You could build these and create a single PROPERTY (PCOMPP or PCOMPLS) and assign these materials to each ply accordingly.

     

  • Frederic Auger
    Frederic Auger New Altair Community Member
    edited July 2023

    Hi,

    thank you for the answer.

     

    I have another question:

    How can I model the bonded interface between the carbon fiber-reinforced plastic and the core material? 

    Do I need to define a new material card for that?

    The bonded interface is the same resin that we use to infuse the carbon fiber.

     

    Best regards,

    Frédéric Auger

  • Vladimir_Gantovnik
    Vladimir_Gantovnik Altair Community Member
    edited March 6

    Guys, do we have any example/tutorial with MAT9ORT core which also have MATX28/MATX68 cards referencing to TABLES1?

    Do we really need tables for all 6 directions (11,22,33,12,23,31)? In Nastran we can give only one TABL3D1 and left all other directions blank.

    Nastran:

    image

    HyperMesh:

    image