Electrical Conductivity

[Kabrera]

Hello everyone

I need to simulate a slotted waveguide antenna and I'm using CST MWS. My problem is that I have constructed the antenna with anozided aluminum and I don't know its electrical conductivity. In my version of CST MWS I can only find aluminium and that makes a 2 dB diference between simulation and real life :sad:
Can anyone tell me the electrical conductivity of the anozided aluminum, please? I've searched on the web and couldn't found it.

Thank you all

 

[JimB]

If you mean anodised aluminium, the surface layer is quite a good insulator, so the conductivity will be quite low.
The surface layer is usually thin, about 0.001" or less I guess.

JimB

 

[Kabrera]

Yes, my mistake, I meant anodised aluminium. But how can I simulate this material without the exact electrical conductivity?

 

[RadioRon]

Anodizing converts the surface of aluminum to aluminum oxide, also called Alumina. The volume resistivity of Aluminum Oxide is greater than 10^14th power, and so it is a good insulator. Perhaps it would be reasonable to model the structure as pure aluminum covered by an insulating dielectric. The dielectric constant of aluminum oxide is about 9.8. The depth of the insulating dielectric is variable depending on the anodizing process, but a good starting value might be .0006 inches.