Edit: It appears to be the missing content from the "Engineering - Heat Treatment Analysis" demo

The pricing in their subscription plan also look quite generous. https://platform.stepfun.com/step-plan

I just wish they put a little bit of energy on making their service usable for non-chinese users. At the moment, their website assumes I speak chinese and when I manually click on "en", the website dynamically translates parts into english, I experience this as half baked solution.