Open Bottom Electric Induction Cold Crucible for Use in Electromagnetic Casting of Ingots
AssigneeConsarc Corporation
InventorGraham A. KEOUGH
Life of this patent
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Abstract
An open bottom electric induction cold crucible with a slotted wall extending below one or more induction coils surrounding the partial exterior height of the crucible is used in an electromagnetic casting process for the production of ingots. A bottom magnetic shield is provided around the outer perimeter of the crucible's slotted wall in the vicinity of the bottom opening and the bottom termination of the wall slots and the bottom connecting member.
Claims18
An open bottom electric induction cold crucible for electromagnetic casting, the open bottom electric induction cold crucible comprising:
- a crucible volume into which a charge can be fed for inductive heating and melting, and subsequent solidification within the crucible volume to form an ingot at the open bottom of the open bottom electric induction cold crucible, the crucible volume formed from an electrically conductive, water-cooled and slot-segmented wall, the electrically conductive, water-cooled and slot-segmented wall having a continuous, electrically conductive and non-slotted perimeter wall region at the open bottom of the open bottom electric induction cold crucible;
- and
- at least one induction coil surrounding a portion of the height of the crucible volume to inductively heat and melt the charge in the crucible volume when an alternating current flows through the at least one induction coil;
- the improvement comprising:
- a bottom electrically conductive magnetic shield disposed around the outer perimeter of the electrically conductive, water-cooled and slot-segmented wall in a crucible bottom region adjacent to the continuous, electrically conductive and non-slotted perimeter wall region.
A method of electromagnetic casting an ingot in an open bottom electric induction cold crucible, the method comprising the steps of:
- supplying a charge of pre-ingot material to a crucible volume formed from an electrically conductive, water-cooled and slot-segmented wall having a continuous, electrically conductive and non-slotted perimeter wall region at the open bottom of the open bottom electric induction cold crucible;
- generating exterior to the electrically conductive, water-cooled and slot-segmented wall at least one magnetic flux field around a portion of the height of the electrically conductive, water-cooled and slot-segmented wall, the at least one magnetic flux field penetrating into the crucible volume to inductively heat and melt the charge of pre-ingot material within the crucible volume to form a molten pre-ingot composition within the crucible volume;
- and
- at least partially solidifying the molten pre-ingot composition within the crucible volume to form the ingot at the open bottom of the open bottom electric induction cold crucible;
- the improvement comprising:
- suppressing the at least one magnetic flux field from penetration into the electrically conductive, water-cooled and slot-segmented wall adjacent to the continuous, electrically conductive and non-slotted perimeter wall region.
A method of electromagnetic casting a silicon ingot in an open bottom electric induction cold crucible, the method comprising the steps of:
- supplying a charge of silicon material to a crucible volume formed from an electrically conductive, water-cooled and slot-segmented wall having a continuous, electrically conductive and non-slotted perimeter wall region at the open bottom of the open bottom electric induction cold crucible;
- generating exterior to the electrically conductive, water-cooled and slot-segmented wall at least one magnetic flux field around a portion of the height of the electrically conductive, water-cooled and slot-segmented wall, the at least one magnetic flux field penetrating into the crucible volume to inductively heat and melt the charge of silicon material within the crucible volume to form a molten silicon composition within the crucible volume;
- and
- at least partially solidifying the molten silicon composition within the crucible volume to form the silicon ingot at the open bottom of the open bottom electric induction cold crucible;
- the improvement comprising:
- suppressing the at least one magnetic flux field from penetration into the electrically conductive, water-cooled and slot-segmented wall adjacent to the continuous, electrically conductive and non-slotted perimeter wall region.
Dependencies are inferred from the claim text.