RU2456116C2 - Method of forming cast moulds - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to metallurgy. Proposed method comprises forming metal female die, casing mould 10 therein from ceramic composition, heating mould 10, extruding mix 26 on surface 24 of mould cavity, and thermal treatment of mix 26. Extruded mix is composed of metal, ceramic or combination thereof. Mix 26 is extruded via nozzle 28 of mix application device 20. Said mould may be produced by slip casting, die casting or injection moulding, or combination thereof.

EFFECT: production of complex surface elements.

8 cl, 10 dwg

Description

FIELD OF THE INVENTION

The present invention relates to casting and, more specifically, to the manufacture of molds used in foundry.

BACKGROUND OF THE INVENTION

Casting processes are widely used in the formation of products. In general, casting processes can be represented as any process in which a fluid material is introduced into a mold, allowed to solidify in it, and then removed in solid form. Examples of casting processes include investment casting, slip casting, gel molding, sand casting, gypsum casting, injection molding, injection molding, grouting, powder molding (compaction), reactive molding, colloidal molding , cold isostatic pressing, hot isostatic pressing and so on. However, investment casting is especially actively used, since the lost wax core allows the formation of castings with higher accuracy than that achievable with other casting processes and is ensured by the efficient production of casting molds.

The investment casting process begins with the manufacture of an expendable wax model having the same geometric shape as the resulting casting. Typically, models are made of wax casting, which is injected into a metal mold during the injection of a wax composition. After receiving the wax model, it is assembled together with other wax components to form a feeder and gate system for supplying casting material. The entire wax unit is then immersed in a ceramic pulp, covered with sand plaster and allowed to dry. The immersion and plastering process is repeated until a coating of the desired thickness is obtained (i.e., about 6-10 mm (0.25-0.675 inches)). Immediately after the ceramic has dried, the entire assembly is placed in a steam autoclave to remove most of the wax. After processing in an autoclave, in the event that additional wax remains in the shell, it is fired in an oven (for example, at a temperature of about 400 ° C). After that, the imprint of the model and system of feeders and gates remains in the ceramic form. Then the mold is preheated to a certain temperature and filled with molten metal, which solidifies in it, forming a metal casting. After the casting has sufficiently hardened, the mold shell is repelled from the casting. Then the feeders and sprues are cut from the casting and finally the casting is subjected to final processing (for example, sandblasting, turning and the like).

In an alternative process, the ceramic mold can be formed into sections, such as half the mold, or even to a larger number of sections that can be assembled together to form a finished mold. This is preferred since the mold can be disassembled to remove castings from it, which allows the mold to be used many times.

Although investment casting allows you to obtain products of improved shape and allows you to mold foundry using the immersion process, investment casting processes, as well as other processes for forming ceramic molds, remain unsatisfactory when reproducing small surface elements. So, for example, lost wax cores having surface elements and / or structures, such as patterns, protrusions and / or patterns that contain complex parts and / or relatively small parts (for example, patterns containing lines whose height is less than or equal to about 0.010 inches), usually poorly reproduced (for example, reproduced unevenly and / or warped) after heat treatment of the form.

As a result, there is a need for methods of molding foundry molds that reproduce surface elements in detail.

SUMMARY OF THE INVENTION

Methods of molding foundry molds and methods of molding products are described.

In one embodiment, the method of forming a mold comprises casting a mold having a cavity surface, forming surface structures on the cavity surface, the surface structures comprising a mixture, and heat treating the mixture. In another embodiment, an article is described.

In another embodiment, the molding method comprises molding the matrix, molding inside the mold using a ceramic composition and a casting process selected from the group including investment casting, slip casting, gel molding, sand casting, casting using gypsum models, injection molding, injection molding, cement injection, powder molding (compaction), reactive molding, colloidal molding, cold isostatic pressing, hot isostatic pressing and combinations comprising at least one of the above processes, heating the mold, extruding the mixture onto the surface of the mold cavity to form surface structures on it, the mixture being extruded through the nozzle of the device, and subsequent heat treatment of the mixture.

In other embodiments, products are manufactured using the described mold forming methods.

The above and other features are illustrated by the following figures and a detailed description.

Brief Description of the Drawings

The figures show examples of implementation options, with the same parts indicated by the same digital positions.

Figure 1 shows, by way of illustration, an example of a first half of a matrix;

figure 2 shows an illustrative example of the second half of the matrix;

Fig. 3 shows, by way of illustration, an example of a first half of a matrix filled with a ceramic composition;

4 shows, by way of illustration, an example of a second half of a matrix filled with a ceramic composition;

Fig. 5 shows, by way of illustration, an example of a second half of a mold extracted from a first half of a matrix;

6 shows, by way of illustration, an example of a first half of a mold extracted from a second half of a matrix;

Fig. 7 shows, by way of illustration, an example of the first and second halves of a complete assembly;

Fig. 8 shows, by way of illustration, an example of a pen applying a mixture to the surface of a cavity of a second matrix, forming protrusions on it;

Fig. 9 shows, by way of illustration, an example of pouring molten metal into a vertical sprue of an assembled matrix to form a turbine blade;

10 shows, by way of illustration, an example of a cast turbine blade that comprises a network of troughs.

DETAILED DESCRIPTION OF THE INVENTION

A method for forming surface structures on molds is described, in which, after the mold is manufactured, ceramic and / or metallic materials are applied to the surface of the mold to form the necessary surface structures on it. Then the material can be subjected to heat treatment to harden and fasten it to the mold. This form can then be used for casting products, and surface structures made in the mold form structures with a "negative geometry" on the casting.

A method of forming surface structures on a ceramic mold provides for the manufacture of molds. The mold can be made using ceramic molding methods, such as investment casting, slip casting, gel molding, sand casting, gypsum casting, injection molding, injection molding, cement grout injection, powder molding (compaction), reactive molding, colloidal molding, isostatic pressing (for example, hot isostatic pressing or cold isostatic pressing), and so on, as well as combinations including at least one of the following methods. The mold is made in such a way that the inner surfaces of the mold are achievable in order to subsequently form surface structures on them. Therefore, the mold can be molded into sections (for example, half of the mold), which can be assembled together to form the finished mold and separated to extract the castings.

The materials used to make the mold may contain materials that can withstand the temperatures that arise when casting the desired castings, such as metal parts, in particular heat-resistant superalloys. Alumina, silica, and the like can be mentioned as examples of such materials.

One of the methods used for molding a mold involves the use of a casting process in which metal matrices are made for molding halves of a mold. The matrices are molded with an internal structure that reproduces the required outer surfaces of the molded part and contains the main shape outlines. For example, in FIG. 1 and 2 are shown as an example, the first half 2 of the matrix and the second half 4 of the matrix. The geometric shape of the first half 2 of the matrix and the second half of the 4 matrix will be used to form the ceramic mold, which should be used for casting the turbine blades. Dies can be made of metals, such as tool steels (for example, steel for casting molds P-20, which contains 0.28-0.40 wt.% Carbon, 0.60-1.00 wt.% Manganese, 0.20 -0.80 wt.% Silicon, 1.40-2.00 wt.% Chromium, 0.30-0.55 wt.% Molybdenum, 0.25 wt.% Copper, 0.03 wt.% Phosphorus and 0 , 03 wt.% Sulfur, according to the American Iron and Steel Institute (AISI)), impact-resistant steels (for example, S2 mold steel, which contains 0.40-0.55 wt.% Carbon, 0.30-0.50 wt.% manganese, 0.90-1.20 wt.% silicon, 0.30 wt.% nickel, 0.30-0.50 wt.% molybdenum, 0.50 wt.% vanadium, 0.25 wt. % copper, 0.03 wt.% phosphorus and 0 , 03 wt.% Sulfur, according to AISI) and so on. More broadly, it is possible to use any metals that can withstand the impact (i.e., will not melt or deform) of the temperatures at which the materials used for molding the mold will be processed, for example, usually at a temperature of about 700 ° C. Matrices can be made using metalworking processes (such as EDM, grinding and grinding), fast manufacturing methods (such as selective laser sintering and layering techniques) and so on, as well as combinations containing at least one of these processes .

After completion of the manufacture of the matrices, as shown in FIGS. 3 and 4, they are filled with ceramic composition 6. Additionally, ceramic composition 6 can be pressed inside the matrices using, for example, mechanical pressing techniques (for example, a punch), isostatic pressing, and so on. In one example, a set of matrices (for example, the first half of 2 matrices and the second half of 4 matrices) is filled with a ceramic composition and then subjected to isostatic pressing, in which the ceramic composition 6 is subjected to a pressure of about 15,000 psi. inch in a pressurized air chamber.

Ceramic composition 6 may use ceramic powders such as alumina, silica, zirconia, zirconium silicate (zircon), aluminum silicate (mullite), yttrium oxide, yttrium silicate, yttrium aluminate (garnit), yttrium aluminate (perovskite), rare earth oxides elements, rare earth silicates, rare earth aluminates and so on, as well as combinations containing at least one of the listed materials. The selection of a specific ceramic powder (s) will be based on the required shape properties, such as thermal conductivity, wear resistance, and so on. The average particle size of the powders used also depends on the desired specific properties, such as surface roughness. The average particle size is usually less than or equal to about 100 microns (microns), and more specifically, it is less than or equal to about 70 microns, and, more specifically, it is less than or equal to about 30 microns. Particle size affects the size of certain surface structures that can be displayed, and the resulting surface quality of the mold. For example, in certain embodiments, the powder used may contain particles with average sizes from about 0.001 microns to about 10 microns.

In addition to various powders, ceramic composition 6 may also contain a liquid medium (such as alcohol (s), water and / or oil (s)) to form a slip. A slip may be preferred if it is capable of flowing into shape parts having a complex geometric shape (e.g., undercuts, channels, and the like). It is also possible to introduce 6 additives into the ceramic composition. Examples of additives include reinforcing fibers (e.g., silica fibers), processing aids (such as mold release agents, e.g. paraffin wax), binders (e.g., polyoxymethylene, starch, cellulose, etc.), as well as combinations containing at least one of the listed materials. It is clear that the materials used for the mold (such as ceramic), the geometric shape of the mold (such as thickness) and other variable characteristics will affect the durability, cost, and performance of the mold. For example, in one embodiment, alcohol may be added to the silica powder to obtain a slip capable of flowing into the matrix with the desired intensity. Quartz fiber is also added to the ceramic composition 6 to increase the strength of the mold, and the thickness of the mold (for example, the walls of the mold, not shown) is set so that the cast material cools down at the right speed in order to obtain the desired microstructure in the casting. Examples of materials are also listed in US patent No. 4989664 (Roth), incorporated herein by reference.

After filling half of the matrix / half of the mold (i.e., half of the matrix, which contain half of the mold in the form of a ceramic composition 6) is subjected to heating. This allows the binder in the ceramic composition 6 to carry out adhesion, forming a loosely bonded mold. Half of the matrix / half of the mold can be heated in the furnace for a time sufficient to form a bond in the ceramic composition 6. In order to enable the conversion of the mold, the temperature at this stage of the process is lower than the sintering temperature. In some circumstances, depending on the additive (s) and / or liquid medium used, half of the matrix / half of the mold may be heated for an additional period of time to remove any moisture or volatile liquids. In such circumstances, the furnace used may be equipped with a drying device capable of drying the air inside the furnace during the process.

During heating, the ceramic composition 6 may to some extent shrink (for example, in volume). If the shrinkage is predicted, the matrices may be given excessive dimensions, so that the resulting shapes will shrink to the desired technical values. The predictability of shrinkage of the ceramic composition can be improved by controlling the composition (e.g., particle size, purity, etc.) and the properties of the ceramic shape (e.g., density). For example, ceramic particle size uniformity, ceramic purity, inclusion of additives, and other variable characteristics can improve predictability of shrinkage. In one embodiment, a hot isostatic pressing process can be used to extrude the ceramic composition 6 when it is heated. The use of such a process can also increase the density of ceramic powders, which helps to reduce shrinkage during sintering of the mold.

After heating the matrices for a predetermined period of time (for example, for about four hours at a temperature of 700 ° C in the case of a non-slip ceramic composition 6), the first half of mold 8 and the second half of mold 10 are cooled (actively and / or passively) and then removed of the halves of the matrix, as shown in Fig.5.

The first half of mold 8 and the second half of mold 10 (which are also referred to as half molds and molds) can be damaged when removed from the halves of the matrix, since the binder provides only a weak bond of the ceramic powder particles. However, with careful handling, the molds may be inspected and / or further modified, remaining in a non-sintered state. For example, as shown in FIG. 7, the first half 8 of the mold and the second half 10 of the mold are assembled together so that their mating can be evaluated, especially in areas along the dividing line 14 and cavity 16. If modification of the molds is required, it can be implemented by machining and / or using other modification methods. For example, in halves of the mold by drilling or turning, an outlet (vents) and a vertical sprue (gate) can be machined, which should facilitate the entry into the cavity 16 of the casting material. In addition, any unevenness on the dividing line 14 can be removed using the grinding operation, after which half of the mold can be provided with mounting parts and / or guides so that the molds are properly aligned during the casting process.

After inspection and possible changes, the forms can be sintered at a temperature sufficient to bond the ceramic powder (s). Typical temperatures that are commonly used for this are from about 1000 ° C to about 2200 ° C. The duration of the sintering process may vary depending on the ceramic composition 6, the mass and geometric shape of the forms, as well as other variables; however, it usually ranges from about 8 hours to about 30 hours. The sintering process may include various stages (for example, the steps of maintaining the temperature, gradually lowering the temperature, gradually cooling, and so on), which can provide a mold with the desired microstructure, reduce deformation, reduce shrinkage, and so on.

After sintering the halves of the mold, they are allowed to cool, after which they undergo some additional processing operations. Examples of such operations are inspection, coating processes (e.g., coatings designed to reduce roughness, wear-resistant coatings, etc.), machining processes (e.g., adding perfumes, adding vertical gates, removing unevenness, etc.), marking processes, fixing processes (for example, inside the bearing support of the form), modification processes (for example, adding guides and adding elements that hold the forms together) and so on. For example, in one embodiment, the cavity 16 (Fig. 7) is polished.

Polishing of the cavity 16 can be performed either by polishing the very inner surface of the cavity 16, for example, using an ultrasonic polishing device with diamond paste, and / or by applying to the desired surface of the coating, polishing the coating, heat treating the coating and re-polishing it. These processes can be repeated as many times as needed to obtain the desired quality of finish. For example, in one embodiment, a slip may be applied to the surface of cavity 16, which contains ceramic powder with particles whose average diameter is equal to or less than about 100 microns. After this, the pulp can be processed on the surface of the cavity (for example, polished) and the surface of the cavity can be sintered. Then the surface can be polished additionally and / or additional coatings can be applied, and the process can be repeated.

More specifically, the inner surface of the cavity 16 may be either ground or polished. Surfaces that have been grinded (for example, formed by grinding processes) typically have an average surface roughness (Ra) whose values are equal to or less than about 50 microinches (or 1.27 microns). Examples of polished surfaces can be represented using a Society for the Plastic Industry's surface finishing system, in particular SPI # 6 surface finish, which represents surfaces obtained using 320 grit sanding paper and having Ra ranging from about 38 to about 42 microinches (from 0.97 μm to 1.07 μm), or surface finish SPI # 4, representing surfaces obtained using sanding paper with a grain of 600 and having a Ra in the range of from about 2 to about mately 3 microinches (0.051 microns to 0.075 microns). Typical polished surfaces (eg, glossy or high gloss surfaces) typically have Ra values that are equal to or less than about 5 microinches (0.127 μm), such as SPI # 3 surface finish, representing surfaces obtained by polishing with No. 15 diamond wheel and having Ra in ranging from about 2 to about 3 microinches (0.051 microns to 0.075 microns), or surface finish SPI # 3, representing surfaces obtained by polishing with a No. 3 diamond wheel and having a Ra of about 1 microinches (0.0 25 μm).

Before or after sintering, molds can be modified in the form of surface structures using a suitable application process. Typical deposition processes include vacuum chemical vapor deposition, ion-plasma deposition, electron beam physical vapor deposition, and electrodeposition. A specific deposition process allows the ceramic material to be applied to the mold surface with the desired accuracy. One typical deposition process is the direct patterning process (Direkt Write, DW), which is also called the “pen type” or “by nozzle” application process. Typical processes for the direct formation of a pattern (e.g., pen, by means of a nozzle, laser, thermal spraying, etc.) are described in US patent application No. 11/170579 (Hardwick et al.) And in published US application No. 2005- 0013926 (Rutkowski et al.), Which are incorporated herein by reference.

On Fig shows that the pen 20 applies the mixture 26 to the surface 24 of the cavity of the second half of the mold 10, forming protrusions 22 on it. The mixture 26 flows through the pen 20 under pressure and exits through the nozzle 28. The applied pressure depends on the desired flow rate, and other variables, such as the inner diameter of the nozzle 28, the viscosity of the mixture 26, and so on. The dimensions of the nozzle 28 are usually from about 0.010 mm to about 1.0 mm, and are selected so as to obtain the desired extrudate diameter.

The pen 20 moves relative to the surface 24 of the cavity and can be carried along the surface 24 of the cavity to form surface structures on it. It is convenient that surface structures (for example, interlayers) can be applied automatically quickly and accurately to a complex surface 24 of the cavity. The movement of the pen 20 in combination with the regulation of the flow rate of the mixtures passing through the pen allows the pen 20 to form interlayers, drops, spots and combinations thereof. In addition, many passes of the pen 20 over the area can create layers of the mixture 26 and / or it is possible to use several feathers in order to accelerate the application process or simultaneously change many surfaces of the molds. Therefore, the pen 20 can form a large number of surface structures, and the term “surface structures” should be interpreted as any shape created by applying a mixture of 26 on the surface, such as patterns (eg, hatching or wavy patterns), drops, spots, interlayers, lines, shapes (e.g. circles, wavy lines, fish scales, honeycombs or polygons) and so on.

The control unit 30 is connected to the pen 20 via an operating connection. The control unit 30 can control the movement of the pen 20, the flow rate with which the mixture 26 is extruded from the pen 20, and other processes and / or operations performed by the device during operation. For example, the cavity surface 24 and the required surface structure (protrusions 22) can be designed and stored in a computer in the form of a CAD / CAM file, which the control unit 30 can access and execute in order to form the required surface structures on the cavity surface 24. Therefore, these methods can be implemented in the form of processes and devices performed by a computer or control unit for the practical implementation of these processes. These methods can also be implemented in the form of a computer program product containing instructions placed on tangible media such as floppy disks, CD-ROMs, hard disks or other storage media that can be read by a computer, moreover, when loading the code of a computer program and executing it computer or control unit, the computer becomes a device designed for the practical implementation of the method. The methods may also be embodied in the form of a code or signal of a computer program stored on a storage medium loaded and / or executed by a computer or control unit, or transmitted via any transmission medium, such as an electric wire or cable, fiber optics, or by electromagnetic radiation, and then, when the code of the computer program is loaded into the computer and executed by it, the computer becomes a device for the practical implementation of the method. When executed on a general-purpose microprocessor, code segments of a computer program configure the microprocessor to create special logic circuits.

The mixture 26, which is used in pen 20, may contain a slip with filling with solid material from about 50 to about 98 wt.% And liquid. The solid material may be metal (e.g. copper, gold, platinum, nickel, cobalt, titanium or iron), ceramics (e.g. alumina, zirconium dioxide, zirconium silicate (zircon), aluminum silicate (mullite), yttrium oxide, yttrium silicate, yttrium aluminate (garnit), yttrium aluminate (perovskite), rare earth oxides, rare earth silicates, rare earth aluminates, silica, silicon carbide and so on) and combinations containing at least one of these materials, for example, heavy-duty alloys based on e cobalt, nickel-titanium alloys and so on. The particular powder used will be selected based on its compatibility with the surface 24 of the cavity (i.e., the ability to create a bond with it), as well as other variables, such as the resulting mixture characteristics (for example, wear resistance or thermal conductivity).

The liquid used in the slip can be any liquid that can be mixed with solid materials and allows solid materials to flow into a form, in particular water, oils, alcohols, ethers, and so on.

Mixture 26 may contain additives such as surfactants, binders (e.g. ethyl silicate and colloidal silica), processing aids (e.g. hard paraffin), viscosity modifiers, blowing agents, and so on. In one embodiment, the mixture contains about 82 wt.% Alumina, about 8 wt.% Starch and about 10 wt.% Isopropyl alcohol.

Mixture 26 can be made in batches. For example, a 100 lb serving can be obtained by adding silica ceramic powder with an average particle size of about 10 microns to the tumbling drum. A starch binder and an alcohol carrier are added to the drum. The mixture 26 is then mixed using a rotating container, a speed mixer, a belt mixer or a shear mixer (for example, a roller machine).

After applying to the surface 24 of the cavity of the protrusions 22, the second half of the mold 10 is heated. During heating, the protrusions 22 (for example, bulges, lines, and so on) harden and weld to the surface 24 of the cavity. In addition, all liquids evaporate, as well as all volatile additives. The time and temperature that are used for sintering the composition will depend, among other variables, on the composition of the mixture 26, the size of the protrusions 22 and the heat source used. Typical examples of heat treatment techniques include focused energy sources (for example, using plasma, microwave radiation, a laser beam, an electron beam, and / or another local heat source). Alternatively, or in addition, the heat treatment may include heating the second half of mold 10 in an oven, provided that the sintering temperature of the mixture 26 is lower than the temperature at which the second half of mold 10 can be damaged.

Additionally, it is possible to use a masking process before the deposition process to mask those parts of the cavity surface 24 that will not contain surface structures. The particular masking used can be material that can adhere to the surface 24 of the cavity and which will be easy to remove from it. In one typical embodiment, an adhesive coated polymer sheet may be used.

After sintering of surface structures (for example, protrusions 22), they are cooled (actively and / or passively). In addition to this, the mold can then be further processed using various operations, such as those described above. In other words, surface structures can be formed on the surface (s) of the half (s) of the mold before and / or after further processing of the mold (e.g., polishing, coating, and other processes described above).

After sintering the molds, they can be assembled and used for casting. Materials that can be cast in them can contain any material (s) for products that melt at a temperature below that which can cause mold damage. In addition, it is desirable that the material flows at a rate at which the cavity of the mold 16 can fill up before solidification, or the mold can be preheated in order to delay solidification. In one typical embodiment shown in FIG. 9, the casting material 34 (e.g., a nickel-based heavy-duty alloy) is heated above its melting point and poured into an assembled vertical sprue 32 to form a turbine blade (e.g., in a cavity 16). In the cavity 16 there are protrusions 22 made during the application process, which will form a recess on the cast blade of the turbine. An example of a cast blade of a turbine 40 is shown in FIG. 10. The blade of the turbine 40 contains surface parts 42 (for example, pits) that were formed during casting on the protrusions 22 on the second half of the mold 10.

After the solidification of the material (s) of the product, the mold is taken apart and a casting is removed from it. At this time, any subsequent or secondary processing operations can be applied (for example, machining, polishing, coating, assembly, and so on).

In another embodiment, the sintering molds may be recycled. Examples of such operations are inspection, coating processes (e.g., coatings designed to reduce roughness, wear-resistant coatings, etc.), machining processes (e.g., adding perfumes, adding vertical gates, removing unevenness, and so on), marking processes, processes fixing (for example, inside the bearing support of the form), modification processes (for example, adding guides and adding elements that hold the forms together) and so on. For example, in one embodiment in a cavity, a thermal barrier coating may be applied to the cavity surface 24, and protrusions 22 are placed thereon to impart a uniform surface finish to the surface.

Surface structures can be made on any ceramic and / or metal matrices and / or molds used for casting, as well as cast parts. In one embodiment, a ceramic injection molding tool for polymers can be obtained when the investment mold of the desired part can be used in the investment casting process to form the ceramic mold. The mold may then be subjected to a deposition process to form detailed patterns on the surface of the mold, which will serve as a decoration on the resulting molds by injection molding. These surface structures may have dimensions equal to or less than about 2000 microns or, more specifically, less than about 1000 microns, or even more specifically, from about 5 microns to about 500 microns.

The processes described herein are particularly useful for forming surface structures on mold surfaces that will be used to form components of a gas turbine engine. While the formation of a turbine blade is discussed here in connection with the high operating temperatures of the turbine, many components used in it are manufactured using casting processes that can use the methods described here, for example, parts that are used at the stage of strong compression in a gas turbine engine, such as stationary aerodynamic surfaces (e.g. nozzles or guiding devices) and rotating aerodynamic surfaces (e.g. blades or vanes). Other components that are used in areas of the gas turbine engine outside the high compression stage include those for controlling the clearance of the bandage, which include flanges, shells and rings, as well as the lining of the combustion chamber and the caps of the combustion chamber. In addition, the application of the described methods is useful in the production of rocket components, such as launch engine cones, stabilizers, and so on. However, it is obvious that the methods described herein are not limited to these applications. Other applications include the automotive industry (e.g. fuel injectors, turbines and turbocharger impellers, fuel reformers, etc.), industrial applications (e.g. filling machine components), computers (e.g. storage drive or cooling components), and so on. as well as the production of plastic products.

The methods for forming surface structures on molds described herein relate to an unmet need for technology. The process allows the formation of a surface represented on the surface of the cavity of the mold, and surface structures may contain complex profiles, patterns, and the like. This method of manufacturing castings with surface structures is particularly useful in modeling castings. In particular, this allows casting manufacturers to start with the production of a standard die, which is used to mold the same number of sets of standard molds (i.e. molds without surface structures). Standard molds can then be modified using the method described herein for applying material to form different surface structures on them. After sintering the surface structures of the mold, they can be used to cast articles having surface parts formed by the surface structures of the mold. For example, it is possible to cast a series of turbine blades with varying surface structures in molds that are all obtained in one matrix. This makes it possible to accelerate research and development in the field of the influence of various surfaces while reducing costs and over a shortened period of time.

The technical and scientific terms used here have the same meaning as is commonly known to one skilled in the art to which the invention relates, unless otherwise specified. The terms “first,” “second,” and the like, as used herein, do not mean any order, quantity, or importance, but rather are used to distinguish one element from another. In addition, the terms given in the singular do not mean quantity limitations, but rather mean the presence of at least one of the mentioned objects, and the terms “front”, “back”, “lower” and / or “upper”, if Unless otherwise specified, they are used merely for convenience of description, and are not limited to any single position or spatial orientation. When reporting ranges, the endpoints of all ranges assigned to a single component or characteristic are inclusive and independently connected (for example, ranges of "up to about 25 wt.% Or, more specifically, from about 5 wt.% To about 20 wt.%" Include endpoints and all intermediate values of the ranges "from about 5 wt.% to about 20 wt.%," and so on). The definition of “approximately” used in connection with a quantity is inclusive of the declared quantity and has a value that is determined by the context (for example, includes the degree of error associated with measuring a certain quantity). As used herein, the plural of the term is intended to include both the singular and the plural of the term that it modifies, thus including one or more units according to this term (for example, dye (s) includes one or more dyes). In addition, the term “combination” as used herein includes averaged products, mixtures, reaction products, and the like. And finally, when using the term “for example,” the following meanings or terms are examples and are not restrictive.

Although the invention has been described with reference to typical embodiments, those skilled in the art will appreciate the ability to make various changes and equivalents of elements without departing from the scope of the invention. In addition, many changes are possible in order to adapt a particular situation or material to the provisions of the invention without departing from its essence. Therefore, it is assumed that the invention is not limited to the specific implementation option described as the best envisioned for the implementation of this invention, but that the invention will include all implementations that fall within the scope of the attached claims.

Claims (8)

1. A method of manufacturing a mold containing casting from a ceramic composition of the mold (8, 10) having a cavity surface (24), forming surface structures on the cavity surface (24), the surface structures comprising a mixture (26) consisting of metal, ceramic, or their combinations, and heat treatment of the mixture (26). 2. The method according to claim 1, in which the formation on the surface (24) of the cavity of surface structures is carried out by extrusion of the mixture (26) through the nozzle (28) of the device (20) for applying the mixture. 3. The method according to claim 2, in which the movement of the nozzle (28) and the flow rate of the extrudable mixture (26) through the nozzle (28) are controlled. 4. The method according to claim 1, in which the surface structure is selected from the group consisting of drawings, drops, smears, layers, lines, profiles and combinations, including at least one of these structures. 5. A method of manufacturing a mold comprising molding a metal matrix (2, 4), casting from a ceramic mold composition (8, 10) in said matrix (2, 4) using a casting process selected from the group including slip casting, casting under pressure, injection molding or combinations thereof, heating the mold (8, 10), extruding the mixture (26) consisting of metal, ceramics or their combinations onto the surface (24) of the mold cavity (8, 10) for molding surface structures on it moreover, the mixture (26) is extruded through the nozzle (28) of the mixture application device (20), and the term processing the mixture (26). 6. The method according to claim 5, in which the movement of the nozzle (28) and the flow rate of the extrudable mixture (26) through the nozzle (28) are controlled. 7. The method according to claim 5, in which the surface structure is selected from the group consisting of drawings, drops, smears, layers, lines, profiles and combinations, including at least one of these structures. 8. The method according to claim 7, including the manufacture of a ceramic mold designed to fill a metal mold with a mold cavity having surface structures to produce a metal cast having surface structures corresponding to surface structures on the inner surface of the mold cavity.

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