What is a solid but a, relatively speaking, very, very cold gas? Put two solids together with no intervening medium, and heat everything up, and you'll see som

What is a solid but a, relatively speaking, very, very cold gas? Put two solids together with no intervening medium, and heat everything up, and you'll see some mixin' and mingling. Often, the reason you don't see more of that sort of thing is because everything is immersed in an oxygen rich fluid with a tendency to create large, relatively reluctant to mix and mingle oxide coatings before anything fun can happen. Hence why another word for cold welding is vacuum welding. Materials, when you really look at em' are not as 'solid' and 'stable' as you may think. Hence why I have a mechanics of materials book I peruse from time to time.