Hearth and casting system

A hearth for use with a casting system, the hearth comprising:

• a cavity comprising:
• a first end portion;
• and
• a second end portion, wherein the cavity defines a cavity cross-sectional area that is continually reduced from the first end portion to the second end portion;
• an inlet at the first end portion, wherein the inlet defines an inlet capacity;
• and
• an outlet at the second end portion, wherein the outlet defines an outlet capacity.

A casting system comprising:

• an energy source;
• and
• a hearth including a sidewall and a skull of material integrally formed in the hearth, wherein the skull of material comprises:
• an inlet defining an inlet cross-sectional area, the inlet defined through the sidewall,
• an outlet defining an outlet cross-sectional area, the outlet defined through the sidewall, and
• a cavity between the inlet and the outlet, wherein the cavity defines a cavity cross-sectional area that is continually reduced from the inlet toward the outlet.

An apparatus for use with a casting system, the apparatus comprising:

• a hearth comprising a sidewall;
• and
• a skull of material integrally formed in the hearth, wherein the skull of material comprises:
• an inlet defining an inlet cross-sectional area, the inlet defined through the sidewall,
• an outlet defining an outlet cross-sectional area, the outlet defined through the sidewall, and
• a cavity between the inlet and the outlet, wherein the cavity defines a cavity cross-sectional area that is continually reduced from the inlet toward the outlet.