Yes, the aluminum honeycomb used for airplanes and that NASA uses for many applications never sees any stress or strain i'm sure. Nor do the aluminum honeycomb propulsion mechanisms for silent submarines. I wonder why nobody told them they shouldn't use those materials?
It is not the aluminum itself that gives strength in a honeycomb. If you don't understand the concept of honeycomb with thin aluminum layers on each side you can click the following link to learn about it.
http://tinyurl.com/kj7fxy
As far as pure aluminum, there are many grades. There are many applications where woofers see MUCH more stress and strain than in an SPL application and aluminum can work just fine. A large tapped horn or even a large horn loaded subwoofer can see extreme amounts of pressure that far surpass what is ever seen in the SPL world. Angles on the cone can greatly change how much stress a cone can take. FEA analysis will allow you to know whether your cone is strong enough before ever making one.
A bad example are the alum dish cones that TC used for awhile. Snoopdan has the video of tearing one up. They had several things going against them. The fact that they become almost flat in the middle, the material they were made from, the fact that they were stamped, and a few other things.
John