If my education serves, every metal has a specific temperature-deformation constant, denoted alpha. This is linear within the elastic range, which on the cold end of things is pretty far. You will not shatter something unless you drop it's temperature from 350 to -100 in a second or something. If it is an even controlled drop it will only shatter if it is very very cold, and stressed. On the hot end of things linear deformation ends when the material becomes maleable, closer to it's melting point. Kevint I think you are thinking of pressure as in lots of pressure. A pressure fit doesn't involve much deformation or stress, it relies on friction. Have you every tried to stick something the "perfect" size into a hole? It will go but its pain in the ass to get in and out. Same concept, but with a little added squeeze. Plus once the fit is formed their are cohesive/stiction forces as well (recall from lapping a hone...).

HOWEVER, JoeD and Bruce you guys has burst my bubble. The softer mediums won't hold up as well. Though I'm going to disagree on aluminum. I have done A LOT of press fits into aluminum, including a catapult swing arm (press fit steel rod into steel bearings, then the steel bearings into aluminum mounts- which was subjected to MASSIVE forces... think a 250psi pneumatic rod as the driving force on a second class lever, operating nearly normal to the pivot, which was press fit, and the pivot had a cross sectional area of .25pi(~.8) in^2) and that held up for around.... I think it was 500 shots before the lever arm (steel) began to crack and had to be replaced, at which point we created new fittings because the old ones were too hard to get apart...)

I'm wondering if the material was very dense and work hardened before hand to relieve stress if it would work...

I'm thinking I should try this on my solid scale (glass or mineral) idea...