CN109663888B

CN109663888B - Method for mold seeding

Info

Publication number: CN109663888B
Application number: CN201811196550.XA
Authority: CN
Inventors: B·D·普泽斯拉夫斯基; D·G·科尼策尔
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 2017-10-16
Filing date: 2018-10-15
Publication date: 2021-07-30
Anticipated expiration: 2038-10-15
Also published as: CN109663888A

Abstract

The present invention provides a method for producing a cast component. The method includes attaching a ceramic mold to a seed crystal, the ceramic mold including a cavity defining a shape of the cast part, and a seed crystal interface having a shape complementary to the seed crystal such that the seed crystal is capable of supporting the ceramic mold in a casting furnace. The method further includes pouring liquid metal into the mold such that the seed portion contributes to controlled crystallization of the cast part.

Description

Method for mold seeding

Technical Field

The present invention relates generally to a method for mold seeding, and more particularly to a method for seeding a mold while preheating the mold for loading into a casting furnace. Accordingly, the present invention may be used in casting operations, such as the casting of superalloys used to fabricate turbine blades and stator vanes for jet aircraft engines or power generating turbine components.

Background

Gas turbine engines typically include at least one compressor to pressurize air to be channeled to the combustor. The engine may include at least one combustor wherein at least a portion of the introduced pressurized air is mixed with fuel and ignited. Hot gas from the compressor flows downstream through at least one turbine section. Each turbine section has rotating blades that rotate about an axis and are contained within an engine casing. The one or more turbine sections may power any of the compressor, fan, shaft, and/or may provide thrust through expansion through the nozzle.

Turbine blades and/or stator vanes in the turbine section must be able to withstand thermal stresses due to high temperatures and large temperature fluctuations and forces due to high rotational speeds experienced during normal operation of the turbine. As turbine pressure ratios and efficiencies increase, the thermal stresses to which the high and low pressure turbine sections are exposed also increase. Thus, in conjunction with manufacturing turbine components (e.g., turbine blades and stator vanes) from high temperature resistant materials, efficient cooling of turbine blades, stator vanes, and other components has become increasingly important and challenging. To combat thermal radiation and convection to the turbine section, several heat removal techniques have been used in the past; fluid cooling is typically used to extend the life of the turbine components. Further, small cooling holes are drilled through the blade at optimized angles to remove heat and provide a thermal barrier on the surface of each airfoil surface of the turbine blade and stator vane. Passages are also formed within the turbine and/or stator vanes to provide convective cooling of each airfoil surface.

The need to increase cooling efficiency within turbine engines has complicated internal cooling passages within turbine components. Conventional techniques for manufacturing engine parts and components involve investment casting or lost wax casting processes. One example of investment casting involves the manufacture of typical blades used in gas turbine engines. Turbine blades and/or stator vanes typically include a hollow airfoil having a radial trench extending along the span of the blade, the trench having at least one or more inlets for receiving pressurized cooling air during operation of the engine. Various cooling passages in the blade typically include serpentine grooves disposed in the middle of the airfoil between the leading and trailing edges. The airfoil typically includes an inlet extending through the blade for receiving pressurized cooling air, the inlet including localized features, such as short turbulator ribs or pins, for increasing heat transfer between the heated sidewall of the airfoil and the internal cooling air.

The manufacture of these turbine blades, typically from high strength superalloy metallic materials, may involve a number of steps as shown in fig. 1 through 4. As shown in FIG. 1, forming a cast part using a conventional investment casting process generally includes the steps of: machining a die 101 for the external wax structure and for the ceramic core; molding and firing the ceramic core 102; molding a wax pattern 103 having a ceramic core; wax component preparation 104; dipping the wax component in a ceramic slurry 105; drying the ceramic slurry to provide a shell 106; dewaxing 107 the shell; casting and leaching (feashing) 108; and drilling cooling holes 109.

In the above process, the precision ceramic core 200 is fabricated to conform to the desired serpentine cooling channel inside the turbine blade. A precision die or mold is also formed that defines the precision 3D exterior surface of the turbine blade, including its airfoil, platform, and integral dovetail. The ceramic core 200 is assembled inside two die halves that form a space or void therebetween that defines the resulting metal portion of the blade. A relatively rigid wax and/or plastic is injected into the assembled die to fill the void and surround the ceramic core 200 where the ceramic core 200 is encapsulated within the wax. The two die halves are separated and removed to expose and remove the rigid wax and/or plastic with the precise configuration of the desired blade 211 formed from the molded wax. A molded wax blade 211 with encapsulated ceramic core 200 is then attached to a wax tree structure 212. The wax tree structure 212 is formed from paraffin wax or any wax that is less rigid than the wax used to form the molded wax blades 211. The dimensional accuracy of the outer surface of the wax used to form the tree structure 212 is less important since the wax of the wax tree 212 will ultimately define the flow path of the molten metal into the ceramic mold. Thus, softer wax is generally used to form the individual paths of the wax tree 212 than is desired for a precision molded wax blade 211. Wax blades 211 require pins 205 to hold the core in place. The tree structure 212 may include a funnel portion 214 for adding molten metal to the mold. As shown in fig. 2 to 4, the tree structure 212 further includes a ceramic filter 213 for filtering molten metal during a casting operation.

After wax injection and wax passage 212 attachment, which forms a wax tree structure, the entire wax tree structure 212, ceramic filter 213 and wax turbine blade 211 are then coated with a ceramic material to form the

ceramic shells

206, 204 as shown in fig. 3. The wax is then melted and removed from the ceramic shell 206, leaving corresponding voids or

spaces

201, 207 between the ceramic shell 206 and the inner ceramic core 200. Further, once the wax tree structure 212 melts, the ceramic shell 204 defines a flow path in fluid communication with the voids or

spaces

201, 207. After the wax is removed, the ceramic core is held in place by pins 205. As shown in fig. 4, molten superalloy metal 208 is then poured into shell 206 through a flow path defined by a portion of ceramic shell 204. The molten superalloy may include any of the following: stainless steel,Aluminum, titanium, Inconel 625, Inconel 718, Inconel 188, cobalt chromium, nickel, and other metallic materials or any alloys; such as a nickel (Ni) superalloy and/or a Ni superalloy single crystal alloy. For example, the above alloys may include the following materials under the trade names: haynes

Haynes

Super Alloy Inconel 625^TM、

625、

625、

625、

6020. Inconel 188, and any other material having material properties that facilitate forming a component using the techniques mentioned above. The molten metal 208 fills the

voids

201, 207 and encapsulates the ceramic core 200 contained in the shell 206. The molten metal 208 is allowed to cool and solidify, and then the outer ceramic shell 206 and inner ceramic core 200 are removed as appropriate, leaving the desired metal turbine blade with internal cooling channels present therein. To provide a path for the removal of the ceramic core material by the leaching process, a ball chute (not shown) and a tip pin (not shown) may be provided. In general, after the leaching process, the ball chutes and tip pin holes in the turbine blades must then be brazed shut.

The cast turbine blade 208 is typically subjected to additional post-casting modifications, such as drilling appropriate rows of film cooling holes through the airfoil sidewall as necessary for providing an outlet for internally-introduced cooling air that then forms a protective cooling air film or layer (commonly referred to as film cooling) on the exterior surface of the airfoil during operation in the gas turbine engine. After the turbine blade is removed from the ceramic mold, the pins 205 holding the ceramic core 200 form passages that will later be brazed shut to provide the desired air path through the internal voids of the cast turbine blade. However, these post-casting modifications are limited and require more intricate internal geometries with the ever-increasing complexity of turbine engines and the recognized efficiency improvements provided by certain cooling circuits inside the turbine blades. While investment casting methods are capable of manufacturing these parts, manufacturing using these conventional manufacturing processes makes positional accuracy and intricate internal geometries more complex and thus significantly increases manufacturing time and expense. Accordingly, there is a need to provide an improved casting method for three-dimensional components having intricate internal voids and cooling circuits.

Additive manufacturing techniques and 3D printing allow molds to be manufactured without tool paths and/or molding limitations associated with subtractive manufacturing. For example, a method of using 3D printing to create a ceramic core-shell mold is described in U.S. patent No. 8,851,151, assigned to ross rice Corporation (Rolls-Royce Corporation). Methods for making the mold include powder bed ceramic processes such as disclosed in U.S. patent No. 5,387,380 assigned to Massachusetts Institute of Technology, and Selective Laser Activation (SLA) such as disclosed in U.S. patent No. 5,256,340 assigned to 3D Systems, Inc. The ceramic core-shell mold according to the' 151 patent is significantly limited by the print resolution capabilities of these processes. As shown in fig. 5, the core portion 301 and shell portion 302 of the integrated core-shell mold 300 are held together by a series of connecting structures 303 provided at the bottom edge of the mold 300. The cooling channels proposed in the' 151 patent include staggered vertical cavities joined by a stub body that is nearly the same length as its diameter. The superalloy turbine blades are then formed in a core-shell mold using known techniques disclosed in the' 151 patent and incorporated herein by reference. After casting the turbine blade in one of these core-shell molds, the mold is removed to reveal the cast superalloy turbine blade.

Fig. 6 illustrates a method of die seeding a mold described in the' 151 patent. The mold 605 has an internal cavity 606 for receiving molten metal. The die 605 has a vented end 607 for passage of gaseous material to and from the internal cavity 606 and a starter seed receiving inlet 609 for receiving and engaging a metal starter seed 608. A metal starting seed crystal 608 is positioned to receive molten metal on surface 608 a. A starting seed crystal assist heater 615 and a supplemental die heater 616 are located within the die 605. Insulation 610 is positioned between the lower surface 605a of the mold 605 and the heat transfer device 611 to minimize heat transfer from the casting mold 605. The heat transfer apparatus 611 includes a pair of

arms

613 and 614 that are movable to a position against and in contact with a surface 618 of the starting seed crystal 608. The abutting relationship of the heat transfer device 611 and the starting seed crystal 608 may be maintained until the

arms

613 and 614 are actively released from the starting seed crystal 608. The precision positioning member 612 contacts the bottom surface 608b of the starting seed crystal 608 to precisely position the vertical height of the melt surface 608a within the molten metal receiving cavity 606. A cooling medium passage 617 is formed in each of the pair of

arms

613 and 614 for passing a cooling medium therethrough. The molten metal within the cavity 605 transfers heat to the starting seed crystal 608, which in turn transfers heat to the cooled pair of

arms

613 and 614 via the surface 618. The cooling medium flowing through the passage 617 removes heat from the

arms

613 and 614. Thus, a temperature gradient is created across the starting seed crystal 608 to cause directional solidification of the molten metal within the cavity 606.

Disclosure of Invention

The following presents a simplified summary of one or more aspects of the disclosure in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.

The foregoing and/or other aspects of the present invention may be achieved by a method of producing a cast component. The method includes attaching a ceramic mold to a seed crystal, the ceramic mold including a cavity defining a shape of the cast part, and a seed crystal interface having a shape complementary to the seed crystal such that the seed crystal is capable of supporting the ceramic mold in a casting furnace. The method further includes pouring liquid metal into the mold such that the seed portion contributes to controlled crystallization of the cast part.

In one aspect, the seed crystal interface of the ceramic mold has a funnel shape, and the seed crystal has a conical shape.

On the other hand, the seed crystal may be attached to a base support in the casting furnace while the ceramic mold is attached to the seed crystal.

In yet another aspect, a ceramic mold may be attached to a seed crystal (seed crystal body), and an over coat (overcoat) of ceramic may be applied to at least a portion of the ceramic mold and the seed crystal to form a cast assembly, and the cast assembly may be secured within a casting furnace prior to pouring the liquid metal.

In another aspect, the casting assembly may be secured within the casting furnace by an attachment mechanism on the seed crystal.

On the other hand, the seed crystal may be a one-piece single crystal metal (one-piece single crystal metal) having an attachment mechanism for securing the seed crystal within the casting furnace.

In yet another aspect, a seed crystal interface of a casting mold includes alignment features corresponding to the alignment features of the seed crystal for controlling a crystallographic orientation of a cast component within the casting mold.

In yet another aspect, the ceramic mold includes channels that offset the seed crystal interface from the cavity of the ceramic mold.

The foregoing and/or other aspects of the present invention may be achieved by a ceramic mold for producing a cast component. In one aspect, a ceramic mold includes a cavity defining a shape of a cast component, a seed crystal interface having a shape complementary to a seed crystal such that the seed crystal is capable of supporting the ceramic mold in a casting furnace, and an alignment feature corresponding to the alignment feature of the seed crystal for controlling a crystallographic orientation of the cast component within the casting mold.

In one aspect, the seed crystal interface of the ceramic mold can have a funnel shape corresponding to the conical shape of the seed crystal

In another aspect, the ceramic mold includes channels that offset the seed crystal interface from the cavity of the ceramic mold.

The foregoing and/or other aspects of the present invention may be achieved by a cast assembly for producing a cast component. The casting assembly includes a ceramic mold including a cavity defining a seed crystal interface and a shape of the cast part; a seed crystal, a seed crystal interface having a shape complementary to the seed crystal; and at least one ceramic cladding coating covering at least a portion of the ceramic mold and the seed crystal to form a cast component.

In one aspect, the casting assembly may further include an attachment mechanism on the seed crystal for securing the seed crystal within the casting furnace.

In another aspect, the seed crystal is a single piece of single crystal metal having an attachment mechanism for securing the seed crystal within the casting furnace.

Other features and aspects may be apparent from the following detailed description, the accompanying drawings, and the claims.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate one or more example aspects of the present disclosure and, together with the detailed description, serve to explain the principles and implementations thereof.

FIG. 1 is a block diagram showing the steps of conventional investment casting;

FIG. 2 is a schematic diagram showing a conventional wax pattern attached to a wax tree structure for investment casting of turbine blades;

FIG. 3 is a schematic view showing the conventional ceramic mold of FIG. 2 after the wax has been removed;

FIG. 4 is a schematic view showing the conventional ceramic mold of FIG. 2 after pouring molten metal into the mold;

FIG. 5 is a schematic diagram showing a perspective view of a prior art integrated core-shell mold having a connection connecting the core and shell segments;

FIG. 6 is a schematic view of a prior art apparatus with a starting seed crystal in a casting mold;

FIGS. 7A and 7B are schematic diagrams illustrating a cross-sectional side view of a ceramic mold and a crystal growth structure according to an embodiment of the invention;

FIG. 8 is a block diagram illustrating a casting process according to an embodiment of the present invention; and

fig. 9A and 9B are schematic diagrams illustrating a cross-sectional side view of a ceramic mold and a crystal growth structure according to another embodiment of the present invention.

Detailed Description

The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts. It will be apparent, however, to one skilled in the art that these concepts may be practiced without these specific details. For example, the present invention provides a preferred method of manufacturing cast metal parts, and preferably those used in the manufacture of jet aircraft engines. In particular, the production of single crystal, nickel-base superalloy cast parts such as turbine blades, vanes and shroud components may be advantageously performed in accordance with the present invention. However, other cast metal parts can be prepared using the techniques of the present invention and integrated ceramic molds.

Typically, single crystal molds require seeding, but the usual methods result in additional steps or compromised seeding conditions. Single crystal molds are typically seeded in two ways. One conventional method is to place a metal seed crystal in a wax component and a shell around it so that the seed crystal is integrated into the mold. Another conventional approach is to incorporate a seed crystal into the cavity of the negative that is shaped as a seed crystal after the ceramic mold is fired. A first aspect of the invention relates to seeding the mold while preheating the mold and loading it into the casting furnace. By creating a seed crystal portion for the normal casting step (i.e., loading into the furnace), the present invention can reduce defects associated with typical methods, such as, for example, oxidation of the seed crystal during mold and seed crystal firing, or inclusion introduction by incorporation into the seed crystal prior to casting.

Fig. 7A is a schematic diagram illustrating a side view of a ceramic mold and a crystal growth structure according to an embodiment of the invention. As shown in fig. 7A, the core 700 may be connected to the shell 701 by a number of filaments 702. Core 700 and shell 701 form a core-shell mold 700/701 that defines a cavity 703 for investment casting a turbine blade. The bottom portion of core-shell mold 700/701 may be configured to have a funnel shape corresponding to ceramic cone 710. According to one aspect, core-shell mold 700/701 may be configured as a seed crystal interface to accommodate ceramic cone 710 such that core-shell mold 700/701 fits tightly onto ceramic cone 710. Core-shell mold 700/701 may be configured with an interface having alignment features that correspond to the alignment features of ceramic cone 710 such that the crystallographic orientation of the resulting cast component may be controlled with core-shell mold 700/701. When attached, ceramic cone 710 and core-shell mold 700/701 may form a cast assembly that will rest on support plate 718. The support plate 718 may be configured with a screw 716. The bottom portion of the ceramic cone 710 may be configured with an attachment mechanism 714 for receiving a screw 716 provided on a support plate 718. The top portion of the ceramic cone 710 may include a seed 712 for solidifying the liquid metal, which is discussed below.

Although the present invention describes the ceramic cone 710 and the seed crystal 712 as separate components, the present invention may not be limited thereto. In another exemplary embodiment, the ceramic cone and seed crystal may be configured as a single crystal metal growth to fit into a ceramic mold. The single crystal metal growth defines a seed crystal configured to match a seed crystal interface. The present disclosure also describes a bottom portion of core-shell mold 700/701 having a funnel shape corresponding to triangular-conical ceramic cone 710, but may not be so limited. The funnel shape of the bottom portion of core-shell mold 700/701 is separated from cavity 703 by channel 711. In this regard, the bottom portion of core-shell mold 700/701 is fluidly connected to cavity 703 by channel 711, channel 711 being configured to offset the bottom portion from cavity 703. In other exemplary embodiments, the configuration of the core-shell mold 700/701 and the bottom portion of the ceramic cone 710 may be various other shapes, such as pyramids, that correspond to each other and allow the bottom portion of the core-shell mold to conform and closely fit onto the ceramic cone.

Fig. 7B is an illustration of a preferred exemplary embodiment, where the support plate 718 is configured to hold a ceramic cone 710 having a core-shell mold 700/701 attached thereto. The top portion of core-shell mold 700/701 may be configured with a channel for pouring molten metal into internal cavity 703.

FIG. 8 is a block diagram illustrating a casting process according to an embodiment of the present invention. By using a Direct Light Printing (DLP) process or any other additive manufacturing method to form a ceramic core-shell mold, the manufacture of the part requires significantly fewer steps than typical investment casting. Fig. 8 shows the following steps: additive manufacturing is used to form ceramic molds and cores 801, prepare wax components 802, ceramic coating 803, dry slurry 804, de-wax and/or firing process 805, and cast and leach ceramic materials 806. It can be appreciated that the steps of ceramic coating 803 and drying slurry 804 can be repeated as shown in fig. 8. The above-described process of forming the mold may include forming the ceramic mold and the core using a DLP process such that the mold is formed as a core-shell structure and is formed of the first photopolymerizable ceramic material. Once the mold is formed, the mold may be combined with several molds and/or wax portions 802 may be added that will form a flow path for the molten material. The core-shell mold and any additional wax structures previously added may then be subjected to a dipping or coating process 803 to form a ceramic coating on the outer surface of the shell of the core-shell mold and on the outer surface of any wax structures added. The core-shell mold may then be subjected to a drying process to dry the slurry 804. As mentioned above, steps 803 and 804 may be repeated. The core-shell mold and outer ceramic shell may then be subjected to a dewaxing and/or firing process 805 to remove the wax and/or sinter the ceramic material forming the mold. It can be appreciated that

steps

802, 803, 804 and 805 may be omitted if the ceramic mold and core in step 801 are made into the final mold shape and are ready for pouring. The molten metal may then be poured into a mold. Once the metal solidifies, the core-shell mold and outer shell can be removed by draining the ceramic material and/or by mechanically removing the mold.

Fig. 9A and 9B are schematic diagrams illustrating a cross-sectional side view of a ceramic mold and a crystal growth structure according to another embodiment of the present invention. In fig. 9A, a first outer ceramic layer 904 may be formed at an outer boundary of the core/shell mold 900/901. For example, the first outer ceramic layer 904 may be formed by a process of dipping a core-shell mold into a ceramic slurry. According to one aspect, for example, the outer ceramic layer may be formed as a single layer by dipping the core-shell mold into a ceramic slurry, drying the slurry, and dipping the core-shell mold into the same ceramic slurry and/or a different type of slurry to form the outer shell on the core-shell mold. The ceramic layer may provide structural mass to the core-shell mold, act as a reinforcement for increasing the durability of the clad core-shell mold, and may improve the thermal properties of the mold. Refractory grains may be sifted onto the slurry coating between the layers. It should be noted that other forms of forming the ceramic coating may be used instead of or in conjunction with the impregnation process mentioned above. For example, ceramic and/or other materials may be sprayed onto the core-shell. For example, the slurries mentioned above may include colloidal silica and ceramic powders (e.g., Al2O3, SiO2, ZrSiO4, ZrO2, Y2O3, AIN, SiC). The above-mentioned grains may be applied between layers and may include 90 to 120 mesh ceramic sand (e.g., Al2O3, SiO2, ZrSiO4, ZrO2, Y2O3, AIN, SiC). Subsequent slurry layers may be applied and subsequent ceramic sand layers of 20 to 70 mesh and/or 10 to 30 mesh may be applied. Once the necessary outer layer is formed on the core-shell, the mold can be fired to sinter the material; thereafter, any of the above-described metals (e.g., superalloys) may be poured into the mold.

According to an exemplary embodiment as shown in fig. 9A and 9B, a second outer ceramic layer 920 may be formed at an outer boundary of the ceramic layer 904. In this regard, the core-shell mold 900/901, the ceramic cone 910 with the seed crystal 912 positioned on top thereof, the ceramic layer 904, and the second outer ceramic layer 920 may be provided as a single cast component to be placed on the support plate 918 and subsequently loaded into a casting furnace (not shown). The second outer ceramic layer 920 may be made of a material and configured to have similar thermal expansion properties as the ceramic cone 910. In this way, cracking or unwanted stresses from heat generated during casting can be avoided. In the case of using the second outer ceramic layer 920, the outer layer may increase the strength of the entire mold and/or modulate the thermal properties of the mold.

According to the exemplary embodiments described above, the seed crystal may be in fluid connection with the inner cavity of the ceramic mold and filled with a liquid metal. When liquid metal is poured into the inner cavity, crystals begin to grow in an upward direction at the seed crystal to produce a solidified cast object. Those skilled in the art will recognize that the seed growth structure according to the present exemplary embodiment is not generally considered to be a support for a ceramic mold that is substantially disposed on a cooled support plate. Once the liquid metal hardens, the ceramic core and shell may be leached out. Upon leaching, the resulting cast object may be a turbine blade.

In accordance with the embodiments described above, the present invention provides unique timing, including the insertion of seed crystals when loading molds into a casting furnace, which is generally impractical when using multi-piece molds. According to one aspect, exposure of the seed crystal to elevated temperatures may be minimized prior to casting, and seed crystal oxidation may be reduced and/or eliminated (e.g., unlike in conventional methods where the mold is fired while placed in wax or externally preheated while bonding). The present invention also facilitates loading into the mold at elevated firing temperatures because the seed crystals do not have to be bonded, thereby eliminating mold thermal cycling. For example, the mold may be loaded directly from the mold firing; likewise, the printed mold can also be loaded directly from the core firing.

This written description uses examples to disclose the invention, including the preferred embodiments, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims. Aspects from the various implementations described, as well as other known equivalents for each such aspect, can be mixed and matched by one of ordinary skill in this art to construct additional implementations and techniques in accordance with principles of this application.

Claims

1. A method of producing a cast component comprising:

attaching a ceramic mold to a seed crystal, the ceramic mold comprising a cavity defining a shape of the cast part and a seed crystal interface having a complementary shape to the seed crystal such that the seed crystal is capable of supporting a ceramic mold in a casting furnace; and

pouring liquid metal into the mold such that a seed portion contributes to controlled crystallization of the cast part,

wherein a seed crystal interface of the ceramic mold has alignment features corresponding to the alignment features of the seed crystal for controlling a crystallographic orientation of a cast component within the ceramic mold.

2. The method of claim 1, wherein a seed crystal interface of the ceramic mold has a funnel shape and the seed crystal has a conical shape.

3. The method of claim 1, wherein the seed crystal is attached to a base support in the casting furnace while the ceramic mold is attached to the seed crystal.

4. The method of claim 1, wherein the ceramic mold is attached to the seed crystal and a ceramic over-coating is applied to at least a portion of the ceramic mold and the seed crystal to form a cast assembly, and the cast assembly is secured within the casting furnace prior to pouring the liquid metal.

5. The method of claim 4, wherein the casting assembly is secured within the casting furnace by an attachment mechanism on the seed crystal.

6. The method of claim 1, wherein the seed crystal is a one-piece single crystal metal having an attachment mechanism for securing the seed crystal within the casting furnace.

7. The method of claim 1, wherein the ceramic mold comprises a channel configured to offset the seed crystal interface from a cavity of the ceramic mold.

8. A ceramic mold for producing a cast component, comprising:

a cavity defining the shape of the cast component;

a seed crystal interface having a complementary shape to a seed crystal such that the seed crystal is capable of supporting the ceramic mold in a casting furnace; and

an alignment feature corresponding to the alignment feature of the seed crystal for controlling a crystallographic orientation of a cast component within the ceramic mold,

9. The ceramic mold of claim 8, wherein a seed crystal interface of the ceramic mold has a funnel shape that corresponds to a conical shape of the seed crystal.

10. The ceramic mold of claim 8, wherein the ceramic mold comprises channels that offset the seed crystal interface from a cavity of the ceramic mold.

11. A casting assembly for producing a cast component, comprising:

a ceramic mold comprising a cavity defining a shape of the cast component, and a seed crystal interface;

a seed crystal, the seed crystal interface having a shape complementary to the seed crystal; and

at least one ceramic cladding coating covering at least a portion of the ceramic mold and the seed crystal to form the cast component,

12. The casting assembly of claim 11, further comprising an attachment mechanism for securing the seed crystal to the seed crystal within the casting furnace.

13. The casting assembly of claim 11, wherein the seed crystal is a single piece of single crystal metal having an attachment mechanism for securing the seed crystal within the casting furnace.