[Partially solved] Set a custom material solely to ONE node

Mods FEM
1

Hello,

I am exploring and editing manually the .inp file for performing different frequency analyses.

However, I have a problem when defining different materials.

How can I define more than one material set?

It is possible to define a material set SOLELY to ONE node?

best regards,
Ekaitz.

2

I think this is more a fem related issue than a material related issue. However don’t know why you need a singe node as another material…

The only way to archive this i thing would be add a point to the model and mark the model as one material and the other part(s) as their own material(s). I think this option would be great also for solo points. In this way can make the single node rigid and or make springs between the the point and the object(s).
For me that would be a great improvement!

3

Thank you Jee Bee. It is true, maybe is FEM related problem. (It is possible to remove the post to FEM?)
I want to see the differences of stiffness and mass very locally when performing a frequency analysis. This is the aim of changing the material of one single node.

Thank you for your solution but I am not sure… I guess that adding a new point should add not only the mass and stiffness in that point, but also the material of whole part… The characteristics of two materials should be added in that point.

4

(Moved to FEM)

5

Thank you.

6

No clue what you meant… here. can you explain?

7

Usually material properties are defined on elements, but in CalculiX there is a special element type for defining mass at node. Look to the manual on the element types and *MASS card
http://www.feacluster.com/CalculiX/ccx_2.13/doc/ccx/node68.html
http://www.feacluster.com/CalculiX/ccx_2.13/doc/ccx/node272.html
e.g.

** define mass element number 2000 at node number 4000 and put it to the element set EM
*ELEMENT, TYPE=MASS, ELSET=EM
2000, 4000

** assign mass properties (mass of 0.1 t if you work in mm and have density in t/mmˆ3) to all elements in the EM element set. 
*MASS, ELSET=EM
0.1
8

I agree that material properties are defined on elements. *MASS card can be a way to achieve what I am doing…

Thank you faldaL.