Once you know the stress-strain relationship, several other engineering properties of a crystal are readily available too. In this video, you meet some of them:
The video mentions the experimental values for the elastic constants of fcc-Cu. Verify that the Born stability conditions are valid for this material. In case you meet problems, please report them in the forum underneath. If you can answer the questions raised by your fellow students, please do so.
Use DFT to calculate the elastic constants of nonmagnetic bcc-Fe (δ-Fe). Examine whether the Born stability conditions are fulfilled (the result might not be what you expect – feel free to speculate about how to reconcile this with the experimental existence of this crystal). If you meet issues or have questions, post them in the forum underneath.