Metallurgical furnace

A device for liquid phase sintering of preforms, said preforms initially comprising powdered material cohesively held together by a fugitive binder, said device comprising:

• a pressure vessel defining an interior pressure chamber;
• a furnace contained within the said pressure chamber, said furnace comprising a top wall, a bottom wall and side and/or end walls which together form a substantially closed furnace chamber,
• each of said furnace walls comprising at least one layer of thermal insulation,
• said bottom wall being constructed of porous insulation to thereby enable a gas to escape,
• each of said furnace top, side and/or end walls comprising a vapor barrier,
• means for heating said furnace chamber and furnace walls above the vaporization temperature of the fugitive binder,
• means for condensating vaporized fugitive binder on the pressure vesel,
• means for selectively providing access to said furnace chamber,
• means for evacuating said pressure chamber to said furnace chamber.

A device for liquid phase sintering of preforms, said preforms initially comprising powdered material cohesively held together by a fugitive binder, said device comprising:

• a pressure vessel defining an interior pressure chamber;
• a furnace contained within said pressure chamber, said furnace comprising a top wall, a bottom wall and side and/or end walls which together form a substantially closed furnace chamber,
• each of said furnace walls comprising at least one layer of thermal insulation,
• each of said furnace top, side and/or end walls comprising a vapor barrier,
• means for heating said furnace chamber and furnace walls above the vaporization temperature of the fugitive binder,
• means for enabling a gas to escape through said bottom wall,
• means for condensating vaporized fugitive binder on the pressure vessel,
• means for selectively providing access to said furnace chamber,
• means for cooling said pressure vessel below the liquification temperature of the fugitive binder, and
• wherein said cooling means comprises a water cooled fluid system in contact with said pressure vessel.

A device for liquid phase sintering of preforms, said preforms initially comprising powdered material cohesively held together by a fugitive binder, said device comprising:

• a pressure vessel defining an interior pressure chamber;
• a furnace contained within said pressure chamber, said furnace comprising a top wall, a bottom wall and side and/or end walls which together form a substantially closed furnace chamber,
• each of said furnace walls comprising at least one layer of thermal insulation,
• each of said furnace top, and/or end walls comprising a vapor barrier,
• means for heating said furnace chamber and furnace walls above the vaporization temperature of the fugitive binder,
• means for enabling a gas to escape through said bottom wall,
• means for condensating vaporized fugitive binder on the pressure vessel,
• means for selectively providing access to said furnace chamber,
• means for introducing a wash gas directly into said furnace chamber,
• a pressure responsive valve having an inlet open to said pressure chamber and an outlet open exteriorly of said pressure vessel, and
• means for igniting gases exhausted from said valve outlet.

A device for liquid phase sintering of preforms, said preforms initially comprising powdered material cohesively held together by a fugitive binder, said device comprising:

• a pressure vessel defining an interior pressure chamber;
• a furnace contained within said pressure chamber, said furnace comprising a top wall, a bottom wall and side and/or end walls which together form a substantially closed furnace chamber, said top wall and each side and/or each wall having a predefined area,
• each of said furnace walls comprising at least one layer of thermal insulation,
• said furnace top wall and each of said furnace side and/or end walls comprising a vapor barrier which extends across the entire area of its respective top, side and/or end wall,
• means for heating said furnace chamber and furnace walls above the vaporization temperature of the fugitive binder,
• means for enabling a gas to escape from said furnace chamber,
• means for condensating vaporized fugitive binder on the pressure vessel,
• means for selectively providing access to said furnace chamber, and
• means for pressurizing said interior pressure chamber.