US 12,434,295 B2
Arcuate seed casting method
Dilip M. Shah, Glastonbury, CT (US); Shiela R. Woodard, South Windsor, CT (US); Steven J. Bullied, Pomfret, CT (US); and Ryan C. Breneman, Newington, CT (US)
Assigned to RTX Corporation, Farmington, CT (US)
Filed by RTX Corporation, Farmington, CT (US)
Filed on Nov. 6, 2023, as Appl. No. 18/387,200.
Application 18/387,200 is a division of application No. 17/490,399, filed on Sep. 30, 2021, granted, now 11,806,780.
Application 17/490,399 is a division of application No. 17/062,035, filed on Oct. 2, 2020, granted, now 11,198,175, issued on Dec. 14, 2021.
Claims priority of provisional application 62/936,196, filed on Nov. 15, 2019.
Claims priority of provisional application 62/911,121, filed on Oct. 4, 2019.
Prior Publication US 2024/0075522 A1, Mar. 7, 2024
Int. Cl. B22D 27/04 (2006.01); B22D 21/02 (2006.01); C30B 11/14 (2006.01)
CPC B22D 27/045 (2013.01) [B22D 21/025 (2013.01); C30B 11/14 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A casting method comprising:
forming a seed, the seed having a first end and a second end, the forming including bending a seed precursor;
placing the seed second end in contact or spaced facing relation with a chill plate;
contacting the first end with molten material; and
cooling and solidifying the molten material so that a crystalline structure of the seed propagates into the solidifying material,
the forming further comprising creating a first region of reduced thickness relative to a thicker second region by removing material including at least one of:
rendering a portion of the seed precursor proximate the first end less prone to stress from the bending than a portion of the seed precursor proximate the second end;
relieving a stress in the seed proximate the first end relative to a stress in a portion of the seed proximate the second end; and
removing stressed material in the seed proximate the first end relative to stressed material in the seed proximate the second end,
wherein:
during the casting, a melt back region of the seed does not extend below the first region to the second region.
 
16. A casting method comprising:
forming a seed, the seed having a first end and a second end, the forming including bending a seed precursor;
placing the seed second end in contact or spaced facing relation with a chill plate;
contacting the first end with molten material; and
cooling and solidifying the molten material so that a crystalline structure of the seed propagates into the solidifying material,
the forming further comprising at least one of:
rendering a portion of the seed precursor proximate the first end less prone to stress from the bending than a portion of the seed precursor proximate the second end;
relieving a stress in the seed proximate the first end relative to a stress in a portion of the seed proximate the second end; and
removing stressed material in the seed proximate the first end relative to stressed material in the seed proximate the second end,
wherein:
the rendering, relieving, or removing forms the seed as a stepped seed, and
the casting is in a shell having a stepped seed cavity accommodating the stepped seed, a step of the seed cavity accommodating a step of the seed.
 
17. A casting method comprising:
forming a seed, the seed having a first end and a second end, the forming including bending a seed precursor;
placing the seed second end in contact or spaced facing relation with a chill plate;
contacting the first end with molten material; and
cooling and solidifying the molten material so that a crystalline structure of the seed propagates into the solidifying material,
the forming further comprising at least one of:
rendering a portion of the seed precursor proximate the first end less prone to stress from the bending than a portion of the seed precursor proximate the second end;
relieving a stress in the seed proximate the first end relative to a stress in the seed proximate the second end; and
removing stressed material in the seed proximate the first end relative to stressed material in the seed proximate the second end,
wherein during the casting, a melt back region of the seed is limited to at least one of and does not extend to a region below said at least one of:
the portion of the seed precursor proximate the first end;
a portion of the seed proximate the first end and subject to said relieving; and
a portion of the seed proximate the first end and subject to said removing material.