One question though, why doesn't Apple go with a carbon fiber or just high quality plastic for the thin and light category?
Everyone wants to get away of plastic...its not good for environment, in the EU now in 10 years they want to be this as law with almost 0 plastic anywhere it make sense...and , aluminium dissipate heat better than plastic...at least there were difference between my plastic macs and al one
But nevertheless...Apple will not go back to plastic...they would be called hypocrite when they say they CARE about environment ..we dont have charger in the iphone box, to make the box smaller...so
Carbon fibre on the other hand...it is the top of sturdy and lightness....F1 cars are count on it...but its also a lot more expensive than 6000/7000series aluminium
Raw - tensile strength, carbon fiber is stronger when is layed up in a composite structure, it is very strong in one direction and weak in another. That is why it is woven into fabric and layed up in different orientations and layers. The real beauty of carbon fiber is that it isn't very difficult to add more material where it is needed by varying the lay up
Also, titanium could be an option, but you need to go with Titanium 6AL-4V segment which is about 120,000 PSI to be a real thing for laptops to be up there with carbon fiber