High Pressure Furnace for Reacting Bi-2212 Superconductor

The stainless-steel furnace is a vertical pressure vessel that is cold wall designed and electrically powered.  The shell has a working pressure of 735 psi, with a 60” tall heater assembly that has six heating zones that are individually controlled.  It has enough power to maintain a temperature of 890C and controlled to within +/-1.5C.  The furnace operates in an environment of Argon and oxygen which is fed at a flow rate controlled through the bottom flange into the annulus space between the heaters and the outside of the Inconel tube. This causes a natural convective flow to occur. Also controlled are the temperature profile, ramp rate, gas mixture, flow rate, max. temperature needed for the exact duration, and cool down profile.  The furnace was designed to produce a homogeneous working zone of one meter or more. All electrical feedthroughs, control thermocouples, pressure transducer and gas inlet are in the base flange while the sample thermocouples and gas outlet are in the top flange which is lifted and lowered by a hydraulic ram.

Advantages:

• No leakage
• No gaps in insulation
• Much larger work zone
• No penetrations in the body tube
• No “make or break” electrical connections