bcgallacher - The melting temperature of steel is around 1400 degrees celcious. The only problem with steel in a jet engine would be the weight, tho this is not an issue if just keep it on my workbench
Aiming for a combustion tempereature of around 900 degrees, the bypass air from the front-fan will allow for some cooling on the exterior of the core also.
Lyman - Yes a web inside the core to house the bearings is one option i have looked into. But then again a web would cause alot of turbulence. So im trying to find a more streamlike design.
The goal with this project is just to get a self-sustaining HB Turbofan running. Any thrust it generates is a pure bonus.