We'd need to get a closer look at your model and how it's defined and what you're changing. Can you post the model?
I've attached the model to this message. The parts that I am interested in changing materials for are the 4 aluminium rods surrounding the central rod. To find the time taken to cool to ambient, I am probing the central rod in the transient study 2.
I have not had a chance to take a look at your model
can you make sure that it is a pack and go? it looks like just the sldasm
also what part/assy should we look at?
and what study? can you make sure both your transient sims are in the model?
i'd also suggest you start with a really simple block to make sure that your understanding of the concepts is solid (maybe a problem with known results) and also that the software is working. then you can move onto your model.
and to note, not having the assy fully defined won't make a difference. mates, sketches...etc don't matter in simulation. but you need to make sure there is a heat path through bonded components. (touching)