Resins for making porous ceramic stereolithography and methods of using the same

Abstract

The present application provides a ceramic resin and a method for forming and using the same. The ceramic resin may include a cross-linkable precursor, a photoinitiator, ceramic particles, and pore-forming particles. The ceramic resin may be used to form a ceramic casting component, for example, by a method comprising the following steps: forming a ceramic resin layer; applying light to the ceramic resin so that the photoinitiator initiates polymerization of the cross-linkable precursor to form a cross-linked polymer matrix that shapes the ceramic particles and the pore-forming particles; then, heating the cross-linked polymer matrix to a first temperature to burn off the pore-forming particles.

Description

Technical Field

[0001] Embodiments of the present specification generally relate to methods of making components using disposable ceramic casting elements. More specifically, embodiments of the present specification relate to the manufacture and use of integral sacrificial cores for investment casting of complex articles, including gas turbine components such as blades, nozzles, and shrouds. Background Art

[0002] Investment casting or lost wax process is used to form complex three-dimensional parts of suitable materials such as metal. For example, investment casting can be used to form a turbine blade including an airfoil integrally joined at its root to a blade platform with a multi-lobed support dovetail integrally joined below the blade platform. The airfoil is hollow and includes one or more radial passages extending along its span, the radial passages starting inside the blade dovetail, the blade dovetail having one or more inlets for receiving pressurized cooling air during engine operation.

[0003] The airfoil may have various forms of complex cooling circuits therein for tailoring the cooling of different portions of the opposing pressure and suction sides of the airfoil between its leading and trailing edges and from the root at the platform to the radially outer tip.

[0004] In existing airfoil designs, complex cooling circuits may include dedicated channels inside the airfoil along the leading edge to provide impingement cooling inside it. Such turbine blades are typically made of high-strength superalloy metal materials in conventional casting processes. In a conventional investment casting or lost wax casting process, a precision ceramic core is first manufactured to conform to the complex cooling channels required within the turbine blade. A precision ceramic casting element or mold is also formed that defines the precise three-dimensional outer surface of the turbine blade, including its airfoil, platform, and integral dovetail.

[0005] The ceramic core is assembled within two mold halves, with the space or void between the mold halves defining the resulting metal portion of the blade. Wax is injected into the assembled mold to fill the void and surround the ceramic core enclosed therein. The two mold halves are separated and removed from the molding wax. The molding wax has the precise configuration of the desired blade and is then coated with ceramic material to form a surrounding ceramic shell.

[0006] The wax is melted and removed from the shell, leaving a corresponding void or space between the ceramic shell and the internal ceramic core. Molten metal is then poured into the shell to fill the void therein and again encapsulate the ceramic core contained in the shell. The molten metal is then cooled and hardened, and the outer shell and inner core are then removed appropriately, leaving the desired metal turbine blade in which the internal cooling channels are obtained.

[0007] The cast turbine blade may then undergo subsequent manufacturing processes, such as appropriately drilling rows of film cooling holes through the sidewall of the airfoil as needed to provide an outlet for the internally directed cooling air, which then forms a protective cooling air film or blanket on the outer surface of the airfoil during operation of the gas turbine engine.

[0008] Therefore, existing methods for manufacturing such complex components require a multi-step process involving the use of wax molds, wax injection and / or external ceramic shell coatings to form a casting mold for the final casting of the component. Therefore, there remains a need for a simplified method for manufacturing gas turbine components, particularly airfoils, having complex internal designs.

[0009] More recently, with the advent of additive manufacturing, ceramic mold cores can be formed by any one or more of a stereolithography (SLA) process, a direct metal laser sintering (DMLS) process, and a selective laser sintering (SLS) process. The SLA process is an additive manufacturing process that uses ultraviolet (UV) light (e.g., a UV laser) to cure a resin in a process that forms a portion of a layer at a time. SLA models are particularly accurate for fit and function studies where fine details are important, and can be used as a master mold for casting silicone and composite tools and a variety of other molding techniques.

[0010] When forming ceramic SLA parts using the SLA process, currently commercially available ceramic stereolithography materials result in completely or nearly completely dense parts without any controlled porosity. However, such dense parts are not particularly suitable for casting cores because the time required to leach the ceramic core material is too long without a certain degree of inherent porosity to facilitate the transport of the leachant into the core. Summary of the invention

[0011] Aspects and advantages will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.

[0012] Ceramic resins and methods of forming and using the same are generally provided. In one embodiment, the ceramic resin includes a cross-linkable precursor, a photoinitiator, ceramic particles, and pore-forming particles. The ceramic resin can be used to form a ceramic casting component. In one embodiment, the method may include: forming a ceramic resin layer; applying light to the ceramic resin so that the photoinitiator initiates polymerization of the cross-linkable precursor to form a cross-linked polymer matrix that sets the ceramic particles and the pore-forming particles; then, heating the cross-linked polymer matrix to a first temperature to burn out the pore-forming particles.

[0013] Technical Solution 1 A ceramic resin comprises: a cross-linkable precursor; a photoinitiator; ceramic particles; and pore-forming particles.

[0014] Technical Solution 2 is a ceramic resin according to Technical Solution 1, wherein the pore-forming particles account for about 0.1 volume percent to about 25 volume percent of the ceramic resin.

[0015] Technical Solution 3: A ceramic resin according to Technical Solution 1, wherein the pore-forming particles account for about 10 volume percent to about 25 volume percent of the ceramic resin.

[0016] Technical Solution 4 is a ceramic resin according to Technical Solution 1, wherein the pore-forming particles include a material that becomes gaseous within a temperature range of about 70°C to about 250°C.

[0017] Technical Solution 5 is a ceramic resin according to Technical Solution 4, wherein the organic material includes naphthalene, naphthalene-related compounds, epoxy resin, acrylic acid, cellulose, polyvinyl alcohol, aluminum acetylacetonate or a mixture thereof.

[0018] Technical Solution 6 A ceramic resin according to Technical Solution 1, wherein the pore-forming particles have an average diameter of about 1 μm to about 100 μm.

[0019] Technical Solution 7: According to the ceramic resin described in Technical Solution 1, the cross-linkable precursor includes an acrylic precursor, an epoxy resin precursor, cellulose, polyvinyl alcohol or a mixture thereof.

[0020] Technical Solution 8 is a ceramic resin according to Technical Solution 1, wherein the ceramic particles account for about 50 volume percent to about 90 volume percent of the ceramic resin.

[0021] Technical Solution 9 is a ceramic resin according to Technical Solution 1, wherein the cross-linkable precursor accounts for about 5 volume percent to about 75 volume percent of the ceramic resin.

[0022] Technical Solution 10 is a ceramic resin according to Technical Solution 1, wherein the photoinitiator accounts for approximately 0.1 volume percent to approximately 4 volume percent of the ceramic resin.

[0023] Technical Solution 11: A ceramic resin according to Technical Solution 1, wherein the photoinitiator cures the cross-linkable precursor when exposed to electromagnetic radiation to form a cross-linked polymer matrix having a burnout temperature of about 250°C to about 500°C.

[0024] Technical Solution 12 A method for forming a ceramic casting element, the method comprising: forming a ceramic resin layer, wherein the ceramic resin comprises a cross-linkable precursor, a photoinitiator, ceramic particles and pore-forming particles; applying light to the ceramic resin so that the photoinitiator initiates polymerization of the cross-linkable precursor to form a cross-linked polymer matrix that fixes the ceramic particles and the pore-forming particles; and then heating the cross-linked polymer matrix to a first temperature to burn out the pore-forming particles.

[0025] Technical Solution 13 is a method according to Technical Solution 12, wherein the first temperature is about 125°C to about 250°C, so that the pore-forming particles are vaporized to form voids in the cross-linked polymer matrix.

[0026] Technical Solution 14 is a method according to Technical Solution 12, wherein the pore-forming particles include organic materials.

[0027] Technical Solution 15 is a method according to Technical Solution 12, wherein, after heating the polymer matrix to the first temperature, the polymer matrix has a porosity corresponding to the volume of the pore-forming particles within the ceramic resin.

[0028] Technical Solution 16 According to the method described in Technical Solution 12, it also includes: after heating the polymer matrix to the first temperature, heating the polymer matrix to a second temperature to burn out the polymer matrix and leave a sintered ceramic core.

[0029] Technical Solution 17 is a method according to Technical Solution 16, wherein the second temperature is greater than the first temperature, and the second temperature is about 250°C to about 500°C.

[0030] Technical Solution 18 provides a method for investment casting a component, the method comprising: casting the component in a ceramic shell including the sintered ceramic core described in Technical Solution 16.

[0031] Technical Solution 19 is a method according to Technical Solution 18, wherein the component is cast by hardening the molten metal in the ceramic shell so that the ceramic core defines a void within the component.

[0032] Technical Solution 20 According to the method described in Technical Solution 18, it also includes: removing the ceramic shell and the sintered ceramic core from the component.

[0033] These and other features, aspects and advantages will become better understood with reference to the following description and appended claims.The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain certain principles of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] A full and complete disclosure of the invention, including the best mode thereof, as known to those skilled in the art, is set forth in the specification with reference to the accompanying drawings, in which:

[0035] Figure 1 is a cross-sectional view of an exemplary component manufactured by one embodiment of the method described herein; and

[0036] Figure 2 shows that it can be used to form Figure 1 A cross-sectional view of an exemplary cast element of an exemplary component.

[0037] Repeat use of reference characters in the present specification and drawings is intended to represent same or analogous features or elements of the invention. DETAILED DESCRIPTION

[0038] Reference will now be made in detail to embodiments of the present invention, one or more examples of which are shown in the accompanying drawings. Each example is provided by way of illustration of the present invention rather than limitation thereof. In fact, it will be apparent to those skilled in the art that many modifications and variations may be made in the present invention without departing from the scope or spirit of the present invention. For example, a feature shown or described as part of one embodiment may be used together with another embodiment to produce a further embodiment. Therefore, the present invention is intended to include such modifications and variations that fall within the scope of the appended claims and their equivalents. As used in this specification, the terms "first", "second" and "third" may be used interchangeably to distinguish one component from another component and are not intended to indicate the position or importance of each component.

[0039] The terms "upstream" and "downstream" refer to the relative directions of the fluid flow in the fluid channel. For example, "upstream" refers to the direction of fluid outflow, while "downstream" refers to the direction of fluid flow.

[0040] Although the embodiments of the present specification can generally describe the manufacture of turbine blades, those skilled in the art should understand that the description should not be limited thereto. The present embodiments are applicable to the manufacture of any component having a core, such as but not limited to turbine blades and parts thereof, turbine nozzles including blades and bands, and shrouds.

[0041] refer to Figure 1, a component 10 is manufactured according to the methods described in this specification. In a particular embodiment, the component 10 includes an outer wall 20 and at least one inner wall 30 disposed in a spaced relationship with the outer wall 20. Such a component is referred to as a "multi-wall component" in this specification. In these methods, a single-piece sacrificial ceramic casting element is provided. Conventional molds are typically configured for multiple uses and are typically a two-piece design, but the complex geometry of the cooling circuit used in the multi-wall component 10 makes it very difficult and often impossible to use a mold with two pieces, which requires additional time and effort in conventional methods to form and assemble multiple injection cores into a composite core. The single-piece sacrificial ceramic casting element includes at least one internal cavity. As used hereinafter, the singular term "cavity" will be used to refer to at least one cavity within the ceramic casting element, but it should be understood that the use of the singular term "cavity" also refers to the case where more than one cavity is contained within the ceramic casting element. The shape of the cavity corresponds to the shape required for the complex core for casting the component 10.

[0042] In accordance with certain embodiments, a single-piece sacrificial ceramic casting element is provided by using one or more additive layer manufacturing processes. This method typically uses a three-dimensional computer-aided drawing ("CAD") file of the product to guide an automated assembly process, wherein the CAD model file is digitally segmented into "slices" corresponding to the actual layers being generated and stacked, and these "slices" guide automated assembly equipment, such as a robotic arm. The nature of the additive layer process allows single-piece products with high internal complexity (e.g., closed internal chambers and tortuous internal passages) to be easily assembled in one continuous operation. Therefore, the additive layer manufacturing process is well suited for forming complex single-piece ceramic casting elements used in embodiments of the present invention, as such ceramic casting elements will typically be designed to have complex internal structures corresponding to the complex internal cooling circuits of the desired cast component.

[0043] Stereolithography (SLA) is an example of an additive layering process suitable for embodiments of the present invention. During SLA, a laser is scanned along a motion path described by a "sliced" CAD file. The laser directs highly focused radiation onto a curable material medium (usually a liquid resin) which hardens ("cures") when exposed to the laser, thereby producing a single accurately rendered cross-sectional layer of the product corresponding to the "slices" of the segmented CAD file. The process is repeated for all subsequent layers, with each layer bonded to the previous layer by the action of the hardened material medium. The finished product is a three-dimensional product with all dimensions rendered in the cured material according to the CAD file.

[0044] Other additive manufacturing processes are available in the art and are suitable for providing a single-piece sacrificial ceramic casting element in embodiments of the present invention, including but not limited to micro-pen deposition, in which a liquid medium is dispensed with high precision at the tip of a pen and then cured. Those skilled in the art will appreciate that a variety of curable material media can be applied, including liquid resins as described above and various forms of solid media, such as powders, wires, and sheets. Siloxane-based and organic-based resins are the most common examples of curable material media used in these methods, although in some methods, the medium includes at least one metal, usually mixed with some type of resin.

[0045] In addition, digital light processing (DLP) can be used to form casting elements. DLP differs from more traditional powder bed and SLA processes in that the photocuring of the polymer is projected onto a photocurable medium or resin as an image of the entire cross section. This usually occurs through a window at the bottom of the resin tank, which projects light onto a thin layer of resin between the window and the build surface, which rises as the process proceeds. Since the entire layer of cured polymer is prepared at the same time, the need to use a laser scan model is eliminated. In addition, polymerization occurs between the bottom window and the last cured layer of the object being built.

[0046] According to the method, a ceramic resin is used to prepare a ceramic casting element (e.g., a plurality of casting cores and / or casting cores / shells). Using its method for forming a ceramic core, the ceramic resin generally incorporates pore-forming particles in its matrix to produce a controlled porosity in the resulting casting element. In one embodiment, the ceramic resin includes a cross-linkable precursor, a photoinitiator, ceramic particles, and pore-forming particles. When exposed to UV light, the photoinitiator begins to polymerize with the cross-linkable precursor to form a solid material. The ceramic particles and pore-forming particles are captured in a solid polymer matrix. In subsequent heating, the pore-forming particles evaporate, leaving voids in the structure. Therefore, the porosity and density of the resulting solidified ceramic core can be controlled. Therefore, the ceramic resin provides a method for forming a ceramic casting element by stereolithography, reducing the entire process cycle time of investment casting.

[0047] A cross-linkable precursor is included in the ceramic resin to form a cross-linked polymer matrix when cured with a photoinitiator to hold the ceramic particles and the pore-forming particles therein. Any suitable cross-linkable precursor may be used in the cross-linkable precursor, including but not limited to an acrylic precursor or an epoxy precursor or a mixture thereof. For alumina-based ceramics, the cross-linkable precursor may include, for example, aluminum acetylacetonate. In most embodiments, the cross-linkable precursor comprises about 5 volume percent to about 75 volume percent of the ceramic resin.

[0048] The resulting crosslinked polymer matrix can have a burnout temperature sufficient for use as a cast component.For example, the crosslinked polymer matrix can have a burnout temperature of about 250°C to about 500°C.

[0049] As described above, the photoinitiator cures the crosslinkable precursor upon exposure to electromagnetic radiation. For example, the photoinitiator can be a UV photoinitiator that cures the crosslinkable precursor upon exposure to UV light (e.g., electromagnetic radiation having a wavelength of about 10 nm to about 400 nm), such exposure can be performed at any suitable temperature, but typically below 50° C. (e.g., at room temperature). The photoinitiator can include benzoin ether derivatives, benzyl ketals, hydroxyalkylphenols, acyclphosphine oxides, organometallic compounds, onium salts (e.g., triarylsulfonium hexafluorophosphates), or mixtures thereof. The photoinitiator comprises about 0.1 volume percent to about 4 volume percent of the ceramic resin.

[0050] The ceramic resin also includes ceramic particles. For example, the ceramic particles can be included in the ceramic resin in an amount of about 50 volume percent to about 90 volume percent (e.g., about 5 volume percent to about 75 volume percent of the ceramic resin). In certain embodiments, the ceramic particles have an average diameter of about 1 μm to about 100 μm. Suitable ceramics for the slurry include, but are not limited to, aluminum oxide, yttrium oxide, ceria, zirconium oxide, magnesium oxide, and calcium oxide.

[0051] Typically, the pore-forming particles are formed from a material that is non-reactive with the resin, insoluble in the resin, and solid at room temperature.

[0052] The pore-forming particles can also vaporize at low temperatures, leaving no residue that can contaminate the ceramic article, but can leave beneficial residues (e.g., dopants, stabilizers, etc.). For example, the pore-forming particles can be a solid material at room temperature that vaporizes / sublimates at a relatively low temperature to produce controlled porosity, such as within a range of about 70°C to about 250°C, such as about 125°C to about 250°C (e.g., about 150°C to about 225°C). For example, in one embodiment, the pore-forming particles include an organic material that becomes gaseous within a temperature range of about 125°C to about 250°C (e.g., about 150°C to about 225°C). The pore-forming particles can form about 0.1 volume percent % to about 25 volume percent % (e.g., about 10 volume percent % to about 25 volume percent %) of the ceramic resin.

[0053] In certain embodiments, the pore-forming particles include naphthalene and / or naphthalene-related compounds (e.g., substituted naphthalene derivatives and terpenes). Naphthalene and its related compounds can sublime at relatively low temperatures. The organic material can include epoxy or acrylic particles, which may have been polymerized so as to decompose with the binder polymer during the firing cycle. Other low thermal decomposition temperature polymers, such as cellulose and / or polyvinyl alcohol, may also be included in the organic material. Aluminum acetylacetonate can be used for alumina-based ceramics or mixtures thereof. In certain embodiments, the pore-forming particles have an average diameter of about 1 μm to about 100 μm.

[0054] After curing, the cross-linked polymer matrix can be heated to a first temperature to burn out the pore-forming particles from the cross-linked polymer matrix. For example, the cross-linked polymer matrix can be heated to a first temperature of about 125°C to about 250°C (e.g., about 150°C to about 225°C) to sublime and / or vaporize the pore-forming particles to create voids in the cross-linked polymer matrix. Thus, after the polymer matrix is ​​heated to the first temperature, the cross-linked polymer matrix has a porosity corresponding to the volume of the pore-forming particles within the ceramic resin. Thus, after the ceramic resin is cured and heated to remove the pore-forming particles to control the density of the resulting ceramic casting component.

[0055] After heating the cross-linked polymer matrix to a first temperature, the porous cross-linked polymer matrix can then be heated to a second temperature to burn off the polymer matrix, leaving behind ceramic particles. For example, the porous cross-linked polymer matrix can then be heated to a second temperature of about 250° C. to about 500° C. (e.g., about 275° C. to about 400° C.). If desired, the resulting ceramic cast element can be sintered by heating to a sintering temperature of about 500° C. or higher (e.g., by a sintering cycle) to ultimately form a cast element.

[0056] The resulting one-piece ceramic casting element is then suitable for investment casting multi-walled components 10. Due to the use of an additive manufacturing process in manufacturing the casting element itself, the complexity of the ceramic core can be much higher than that possible in a one-piece core made by conventional techniques. The core is typically fired at a second temperature greater than about 500° C. (e.g., about 700° C. to about 1000° C.) to provide the core with sufficient strength to withstand subsequent operations.

[0057] The ceramic core manufactured as described above can then be used as part of a core assembly to perform an investment casting process to form the component 10. Typically, cores and appropriate auxiliary materials known to those skilled in the art (e.g., locating pins and support pins, casting gates, pouring gates, etc.) are arranged in a mold that is appropriately shaped according to the design of the component to be cast. Wax is injected into the mold and hardened to form a wax model, and the wax model with embedded cores is repeatedly immersed in a ceramic slurry to form a ceramic shell mold around the wax model. After removing the wax, only the ceramic core arranged in and attached to the ceramic shell mold remains, thereby forming the above-mentioned core assembly. After the component is cast by hardening the molten metal in the core assembly, the ceramic mold is removed by chemical or mechanical means, and the core is "leached" out of the component by a chemical remover.

[0058] However, in other embodiments, the use of wax may be avoided when the casting element includes both a casting core and a casting shell, such as formed by an additive manufacturing process using the ceramic resin described above. Figure 2 A casting element 100 is shown including an outer shell 102 that defines an outer surface of the resulting cast component; a casting core element 104 that defines internal passages (e.g., cooling holes) within the resulting cast component; an inner shell 108 that defines an inner wall of the resulting cast component; and an inner casting element 110 that defines an inner cavity of the resulting cast component. As described above, each of these casting elements 102, 104, 108, 110 can be manufactured by additively manufacturing a ceramic resin, followed by curing (e.g., by light) to cross-link a precursor, heating to burn out pore-forming particles at a first temperature, and further heating to burn out the polymer material at a second temperature. The open area 106 corresponds to the cast component design, such as Figure 1 As shown, the component can then be cast and hardened within these open areas 106. The cast elements 102, 104, 108, 110 can then be removed by leaching by chemical or thermal methods.

[0059] The use of one-piece ceramic casting elements, particularly in embodiments employing SLA or other additive layer manufacturing processes, allows for repeatable production of high quality castings without the time consuming steps of forming multiple core components and joining them together to form a composite core prior to wax injection.

[0060] The above method is applicable to forming any investment casting product. In some embodiments, the manufactured component 10 is a component of a turbine assembly, such as a turbine blade or vane, including a multi-walled blade or vane. In a specific embodiment, the component 10 includes at least one internal air cooling channel 40. Because the additive manufacturing process used to form the ceramic casting element is easily adapted to the complexity of the internal channel geometry, it is easy to add additional features to the component at little additional cost. For example, in some embodiments, at least one cooling channel 40 of the component 10 includes a turbulator (not shown) to enhance heat transfer within the cooling channel 40.

[0061] The advantages provided by the method of the present invention are most apparent when such complex multi-walled components are manufactured using the method of the present invention, due to the time and cost savings of directly forming the ceramic core as described above. For example, one embodiment of the present invention is a method for manufacturing a component of a turbine assembly. The component is a multi-walled component, so it includes an outer wall and at least one inner wall disposed in a spaced relationship with the outer wall, and also includes a

[0062] The method includes: forming a ceramic resin into a casting element using a stereolithography process; curing the resin to form a cross-linked polymer matrix; heating the cross-linked polymer matrix to a first temperature to burn out pore-forming particles to form voids in the cross-linked polymer matrix; thereafter heating the cross-linked polymer matrix to a second temperature to burn out polymer material, leaving a ceramic core (e.g., substantially free of organic material); and performing an investment casting process using the ceramic casting element as part of a core assembly to form the component.

[0063] Other embodiments of the present invention include methods for making casting cores, and casting elements made by the method. In the method, a one-piece ceramic casting core is made using the additive layer manufacturing method described above. In a particular embodiment, the casting element is configured to form internal channels, such as air cooling channels, in the investment casting product. That is, the core is designed to correspond to the geometry of these channels so that when the investment casting process is performed, the ceramic core will be leached from the inner surface of the component, leaving the desired internal channel configuration. In some embodiments, the investment casting product for which the core is constructed is a component of a turbine component, such as a multi-wall component.

[0064] This written description uses exemplary embodiments to disclose the present invention, including the best mode, and also enables any person skilled in the art to practice the present invention, including making and using any device or system and performing any included method. The patentable scope of the present 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 appended claims if they have structural elements that do not differ from the literal language of the appended claims, or if they include equivalent structural elements that are not substantially different from the literal language of the appended claims.

Claims

1. A ceramic resin comprising: Crosslinkable precursors; Photoinitiator; Ceramic particles, wherein the ceramic particles account for 50 volume percent to 90 volume percent of the ceramic resin; and a pore-forming particle, wherein the photoinitiator is a UV photoinitiator configured to initiate polymerization of the UV photoinitiator and the cross-linkable precursor upon exposure to UV light at a temperature below 50° C. to form a cross-linked polymer matrix that shapes the ceramic particle and the pore-forming particle; wherein the pore-forming particles include a material that becomes gaseous within a temperature range of 70° C. to 250° C.; and Wherein, the material includes aluminum acetylacetonate.

2. The ceramic resin according to claim 1, wherein The pore-forming particles account for 0.1 volume % to 25 volume % of the ceramic resin.

3. The ceramic resin according to claim 1, wherein The pore-forming particles account for 10 volume % to 25 volume % of the ceramic resin.

4. The ceramic resin according to claim 1, wherein The material also includes naphthalene, naphthalene-related compounds, epoxy resins, acrylic acid, cellulose, polyvinyl alcohol or a mixture thereof.

5. The ceramic resin according to claim 1, wherein The pore-forming particles have an average diameter of 1 μm to 100 μm.

6. The ceramic resin according to claim 1, wherein The cross-linkable precursor includes an acrylic precursor, an epoxy resin precursor, cellulose, polyvinyl alcohol or a mixture thereof.

7. The ceramic resin according to claim 1, wherein The cross-linkable precursor accounts for 5 volume % to 75 volume % of the ceramic resin.

8. The ceramic resin according to claim 1, wherein The photoinitiator accounts for 0.1 volume % to 4 volume % of the ceramic resin.

9. The ceramic resin according to claim 1, wherein The photoinitiator cures the cross-linkable precursor upon exposure to electromagnetic radiation to form the cross-linked polymer matrix having a burn-off temperature of 250°C to 500°C.

10. A method of forming a ceramic cast component, the method comprising: forming a ceramic resin layer, wherein the ceramic resin comprises a cross-linkable precursor, a photoinitiator, ceramic particles, and pore-forming particles, wherein the ceramic particles account for 50 volume percent to 90 volume percent of the ceramic resin, and wherein the photoinitiator is a UV photoinitiator configured to initiate polymerization of the UV photoinitiator and the cross-linkable precursor upon exposure to UV light at a temperature below 50° C. to form a cross-linked polymer matrix that fixes the ceramic particles and the pore-forming particles; applying light to the ceramic resin so that the photoinitiator initiates polymerization of the cross-linkable precursor to form the cross-linked polymer matrix that shapes the ceramic particles and the pore-forming particles; then heating the cross-linked polymer matrix to a first temperature to burn out the pore-forming particles; wherein the first temperature is between 125°C and 250°C, so that the pore-forming particles are vaporized to form voids in the cross-linked polymer matrix; and Wherein, the pore-forming particles include aluminum acetylacetonate.

11. The method according to claim 10, wherein: After heating the cross-linked polymer matrix to the first temperature, the cross-linked polymer matrix has a porosity corresponding to the volume of the pore-forming particles within the ceramic resin.

12. The method according to claim 10, further comprising: After heating the cross-linked polymer matrix to the first temperature, the cross-linked polymer matrix is ​​heated to a second temperature to burn out the cross-linked polymer matrix, leaving a sintered ceramic core.

13. The method according to claim 12, wherein: The second temperature is greater than the first temperature, and the second temperature is 250°C to 500°C.

14. A method of investment casting a component, the method comprising: Making a sintered ceramic core according to the method of claim 12; as well as The component is cast in a ceramic housing including the sintered ceramic core.

15. The method according to claim 14, wherein: The component is cast by hardening molten metal in the ceramic shell such that the sintered ceramic core defines a void within the component.

16. The method according to claim 14, further comprising: The ceramic shell and the sintered ceramic core are removed from the component.

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