One of my collegues created an NX Open program in NX 8.5 to generate material properties coefficients from test data via curve fitting. That program no longer works in newer versions due to changes in XY graphing tools. However, the same individual created a python script to do most of what the NX Open program does. I've not tried it and am really ghost writing here. But here are instructions that I have on how to use the python script.
I previously sent this to a user in November of last year. He downloaded WinPython version 22.214.171.124Qt5 and it worked fine for him. Our services group was given the task of creating an NX Open program to replace the one from NX 8.5. I don't know if that's been done yet, but will post it here if it has been done.
Simulation Product Management
Simulation and Test Solutions
Siemens Industry Sector
Siemens Product Lifecycle Management Software Inc.