Usually, if a material requires an additional license it will be specified in the user manual. For example, *MAT_161-162:
I don't see *MAT_318 in the R13 nor the R14 user manual Vol II:
But, it is in our DEV user manual:
You can try with R14.
If it does not work, you will need a DEV solver. We cannot provide files via the Ansys Forum. If you need the DEV solver, please submit a service request (SR) on the Ansys customer portal:
Let me know how it goes.