Comment by jordanb

Ok I looked this up because I found it very strange.

Inconel would not be a good choice for an automobile frame. Not only is it expensive and heavy it also can be pretty brittle. You want a frame that's strong but ductile so that it will absorb impact energy.

From what I've been able to find, Tesla uses inconel in some battery components. This makes sense because the thing inconel is really good at is staying strong even when very hot. This is why it's used in turbines and jet engines.

This thread points out that inconel is not unused in the automotive world, high-end ICE cars have used it for their exhaust systems. Another advantage of inconel in this application is that it's highly corrosion resistant:

https://teslamotorsclub.com/tmc/threads/inconel.50251/

So in summary: Tesla uses inconel where it makes sense to use it (to deal with high heat) and so do other automobile manufactures.