Compound furnace

A compound debinding and sintering furnace with controlled contamination, comprising:

• an outer insulation at least partially enclosing a sealed housing;
• an inner insulation disposed within the sealed housing;
• an inner heater system including at least one inner heater and disposed within the sealed housing and configured to heat a work zone an outer heater system including at least one outer heater;
• at least one controller configured to operate the inner heater system and outer heater system, cooperatively with one another, to heat the work zone to a sintering temperature of at least 1250° C.;
• wherein the outer heater system is configured to heat the inner insulation layer from outside the sealed housing to a temperature at which contaminants outgassed from a part, heated to a debind temperature, are inhibited from condensing in the inner insulation layer;
• and
• a plate including:
• an inner seal,
• an outer seal,
• and a gas channel,
• wherein the outer seal is in gaseous communication with the gas channel disposed between the inner seal and the outer seal, and
• a feed configured to deliver a sweep gas to between the inner seal and the outer seal such that the sweep gas transits through the outer seal.

A compound debinding and sintering furnace with controlled contamination of debinding and sintering parts, comprising:

• an outer insulation layer;
• an inner insulation layer disposed within the outer insulation layer and having an internal hot face surrounding a work zone;
• a sealed housing surrounding the inner insulation layer and composed of a refractory material capable of withstanding a service temperature, the service temperature being greater than a debinding temperature that is less than 1000 C, and less than a sintering temperature that is greater than 1250 C;
• an outer heater system configured to heat at least a portion of the sealed housing and externally heat the inner insulation layer (i) in conjunction with an inner heater system, heat the work zone to the debinding temperature and (ii) inhibit condensation of a binder within and upon the inner insulation layer during a debinding process;
• wherein the inner heater system is configured to internally heat the inner insulation and contribute a majority of heating to heat the work zone to the sintering temperature during a sintering process;
• a housing door operable as an openable and closeable portion of the sealed housing;
• an outer door insulation that serves as a portion of the outer insulation layer and an inner door insulation that serves as a portion of the inner insulation layer, wherein the outer door insulation is disposed between the housing door and the inner door insulation;
• a high-temperature seal arrangement disposed between the outer door insulation and the inner door insulation and configured for providing gaseous isolation therebetween, and the high temperature seal arrangement includes an inner seal and an outer seal in gaseous communication with a gas channel disposed between the inner seal and outer seal;
• and
• a gas feed configured to deliver a sweep gas to the gas channel such that the sweep gas transits through the outer seal to inhibit ingress of gaseous contaminants from the outer seal to the inner seal.