CN115213346A - Preparation method of high-strength crystal selector of single crystal blade - Google Patents

Preparation method of high-strength crystal selector of single crystal blade Download PDF

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Publication number
CN115213346A
CN115213346A CN202110409370.0A CN202110409370A CN115213346A CN 115213346 A CN115213346 A CN 115213346A CN 202110409370 A CN202110409370 A CN 202110409370A CN 115213346 A CN115213346 A CN 115213346A
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China
Prior art keywords
crystal
crystal selector
selector
inner cavity
single crystal
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CN202110409370.0A
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Chinese (zh)
Inventor
孟杰
王猛
张朝威
邹明科
王新广
李金国
周亦胄
孙晓峰
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Institute of Metal Research of CAS
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Institute of Metal Research of CAS
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Priority to CN202110409370.0A priority Critical patent/CN115213346A/en
Publication of CN115213346A publication Critical patent/CN115213346A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C1/00—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C9/00—Moulds or cores; Moulding processes
    • B22C9/02—Sand moulds or like moulds for shaped castings
    • B22C9/04—Use of lost patterns
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C9/00—Moulds or cores; Moulding processes
    • B22C9/10—Cores; Manufacture or installation of cores
    • B22C9/105—Salt cores
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C9/00—Moulds or cores; Moulding processes
    • B22C9/22—Moulds for peculiarly-shaped castings
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/10—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on aluminium oxide
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
    • C04B35/14—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on silica
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C04B35/622—Forming processes; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3205—Alkaline earth oxides or oxide forming salts thereof, e.g. beryllium oxide
    • C04B2235/3206—Magnesium oxides or oxide-forming salts thereof
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3217—Aluminum oxide or oxide forming salts thereof, e.g. bauxite, alpha-alumina
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3224—Rare earth oxide or oxide forming salts thereof, e.g. scandium oxide
    • C04B2235/3225—Yttrium oxide or oxide-forming salts thereof
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/34—Non-metal oxides, non-metal mixed oxides, or salts thereof that form the non-metal oxides upon heating, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3418—Silicon oxide, silicic acids, or oxide forming salts thereof, e.g. silica sol, fused silica, silica fume, cristobalite, quartz or flint
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
    • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
    • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
    • C04B2235/34—Non-metal oxides, non-metal mixed oxides, or salts thereof that form the non-metal oxides upon heating, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
    • C04B2235/3427—Silicates other than clay, e.g. water glass

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Crystals, And After-Treatments Of Crystals (AREA)

Abstract

The invention relates to the technical field of investment precision casting, in particular to a preparation method of a high-strength crystal selector of a single crystal blade. The method comprises the following specific steps: designing an inner cavity die and an outer shape die of the crystal selector, and processing the inner cavity die and the outer shape die for the crystal selector according to the design structure; pressing an inner cavity blank of the crystal selector by using an inner cavity die and a water-soluble core material, putting the inner cavity blank into an outer die, and pressing a main body structure of the crystal selector by using a ceramic material by using the outer die; and then dissolving the intermediate inner cavity water-soluble core blank with water to obtain a wet blank of the crystal selector, and roasting and strengthening the wet blank to obtain the crystal selector for investment casting of the single crystal blade. The invention can avoid the problem that the wax mould is fragile, improve the rate of finished products of shell making, and effectively avoid the problem of steel leakage caused by the weakness of a crystal selector in the directional solidification process.

Description

Preparation method of high-strength crystal selector of single crystal blade
Technical Field
The invention relates to the technical field of investment precision casting, in particular to a preparation method of a high-strength crystal selector of a single crystal blade.
Background
With the continuous development of the technology of aero-engines and gas turbines, the performance requirements of the blade are gradually improved, and the single crystal high temperature alloy blade becomes the first choice of a hot end part of the engine. The single crystal high temperature alloy blade is manufactured by investment casting, and is most different from an isometric crystal blade in that a single crystal structure is obtained through a crystal selector, and the single crystal blade is obtained in a directional solidification mode on the basis of the single crystal structure. The quality of the fabrication of the seed selector directly determines the orientation control and quality of the single crystal blade.
At present, most of crystal selectors are manufactured by pressing wax materials into wax molds and directly connecting the wax molds with blade wax molds. Therefore, it is desirable to produce a stronger seed selector.
Disclosure of Invention
The invention aims to provide a preparation method of a high-strength crystal selector of a single crystal blade.
The technical scheme of the invention is as follows:
a preparation method of a high-strength crystal selector of a single crystal blade comprises the following specific steps:
(1) Designing an inner cavity die and an outer shape die of the crystal selector, and processing the inner cavity die and the outer shape die for the crystal selector according to a designed structure;
(2) Pressing an inner cavity blank of the crystal selector by adopting a water-soluble core material through an inner cavity die of the crystal selector;
(3) Placing the inner cavity blank into an outer mold of the crystal selector, and pressing a main body structure of the crystal selector by using a ceramic material through the outer mold;
(4) Removing the inner cavity blank by water solution to obtain a wet blank of the crystal selector;
(5) And roasting and strengthening the wet blank of the crystal selector to obtain the crystal selector for the investment casting of the single crystal blade.
According to the preparation method of the high-strength crystal selector with the single crystal blades, the diameter of the spiral section of the crystal selector is 1-10 mm, and the pitch of the spiral section is 1-10 mm.
According to the preparation method of the high-strength crystal selector for the single crystal blade, a water-soluble core material adopts a urea core material or a gypsum core material.
According to the preparation method of the high-strength crystal selector for the single crystal blade, the ceramic material is a silicon-based ceramic material or an aluminum-based ceramic material.
The preparation method of the high-strength single crystal blade crystal selector comprises the following steps of 65-75% of quartz glass powder, 8-10% of fused corundum powder, 15-25% of zirconium silicate powder and 0.5-1.5% of additives in percentage by weight, wherein the additives are magnesium oxide or yttrium oxide.
The preparation method of the high-strength single crystal blade crystal selector comprises the following steps of 68-72% of aluminum-based ceramic material, 26-30% of quartz glass powder and 1-3% of additive by weight, wherein the additive is magnesium oxide or yttrium oxide.
The preparation method of the high-strength crystal selector for the single crystal blade has the advantages that the sintering temperature is 1200-1600 ℃, and the heat preservation time is 2-10 hours.
The design idea of the invention is as follows:
the crystal selector is complex in structure, the water-soluble core material and the ceramic material are adopted to prepare the crystal selector, the water-soluble core material is removed to obtain a high-strength crystal selector blank, and the high-strength ceramic crystal selector is obtained by high-temperature sintering and low-temperature strengthening of ceramic. Because the whole crystal selector is made of ceramic materials, the size of the crystal selector can be optimized, the strength of the crystal selector can be greatly improved, and the problem of scrapping caused by low strength of the wax crystal selector is solved.
The invention has the following advantages and beneficial effects:
1. the invention is suitable for preparing the single crystal high temperature alloy blade casting.
2. The invention is easy to operate and control and is suitable for batch production.
3. The method can avoid the problem that the wax mold is fragile, improve the yield of the single crystal blade shell manufacturing, and effectively avoid the problem of steel leakage caused by the weakness of a crystal selector in the directional solidification process.
4. The crystal orientation qualified rate of the single crystal blade casting prepared by the invention is equivalent to that of the blades prepared by other methods.
Detailed Description
The present invention will be described in further detail by way of examples.
Example 1
In this embodiment, a crystal selector mold is designed, the diameter of the spiral section of the crystal selector is 1.2mm, and the pitch of the spiral section is 3mm. The method comprises the following steps of firstly pressing an inner cavity blank of the crystal selector by using a urea core material through an inner cavity die, then placing the inner cavity blank into an outer shape die, pressing a main structure of the crystal selector by using a silicon-based ceramic material (according to weight percentage, the silicon-based ceramic material comprises 70% of quartz glass powder, 9% of fused corundum powder, 20% of zirconium silicate powder and 1% of additive, and the additive is magnesium oxide), then placing the main structure of the crystal selector into water at room temperature for 20min, and then removing the urea core material to obtain a wet blank of the crystal selector. And then placing the formed wet blank of the crystal selector in a roasting furnace, heating the wet blank to 1200 ℃ along with the furnace, preserving heat for 5 hours, cooling along with the furnace, and infiltrating and strengthening by using silica sol to obtain the crystal selector.
The crystal selector is prepared by the process, 10 single crystal blades are prepared after the crystal selector is combined with the blades, the shells of the 10 single crystal blades are intact, no steel leakage exists in the casting process, all the 10 single crystal blades axially grow to be in the orientation of <001>, and the deviation angle is not greater than 15 degrees.
Example 2
In this embodiment, a die of a crystal selector is designed, the diameter of the spiral section of the crystal selector is 3mm, and the pitch of the spiral section is 8mm. The method comprises the steps of firstly pressing an inner cavity blank of the crystal selector by using a urea core material through an inner cavity die, then placing the inner cavity blank into an outer shape die, pressing a main structure of the crystal selector by using a silicon-based ceramic material (the silicon-based ceramic material comprises 70% of quartz glass powder, 9% of fused corundum powder, 20% of zirconium silicate powder, 1% of additive and magnesium oxide in percentage by weight), then placing the main structure of the crystal selector into water at room temperature for 20min, and then removing the urea core material to obtain a wet blank of the crystal selector. And then placing the formed wet blank of the crystal selector in a roasting furnace, heating the wet blank to 1400 ℃ along with the furnace, preserving heat for 4 hours, cooling along with the furnace, and infiltrating and strengthening by using silica sol to obtain the crystal selector.
The crystal selector is prepared by the process, 10 single crystal blades are prepared after the crystal selector is combined with the blades, the shells of the 10 single crystal blades are intact, no steel leakage exists in the casting process, all the 10 single crystal blades axially grow to be in the orientation of <001>, and the deviation angle is not greater than 15 degrees.
Example 3
In this embodiment, a crystal selector mold is designed, the diameter of the spiral section of the crystal selector is 6mm, and the pitch of the spiral section is 15mm. Firstly, pressing an inner cavity blank of a crystal selector by using a gypsum core material through an inner cavity die, then placing the inner cavity blank into an outer shape die, pressing a main body structure of the crystal selector by using an aluminum-based ceramic material (the aluminum-based ceramic material comprises 70% of alumina powder, 28% of quartz glass powder and 2% of additive in percentage by weight, and the additive is yttrium oxide), then placing the main body structure of the crystal selector into water at room temperature for 10min, and removing the gypsum core material to obtain a wet blank of the crystal selector. And then placing the formed wet blank of the crystal selector in a roasting furnace, heating the wet blank to 1600 ℃ along with the furnace, preserving the heat for 10 hours, cooling along with the furnace, and infiltrating and strengthening by using silica sol to obtain the crystal selector.
The crystal selector is prepared by the process, 10 single crystal blades are prepared after the crystal selector is combined with the blades, the shells of the 10 single crystal blades are intact, no steel leakage exists in the casting process, all the 10 single crystal blades axially grow to be in the orientation of <001>, and the deviation angle is not greater than 15 degrees.
The embodiment result shows that the preparation method of the crystal selector is mainly used for preparing the single crystal blade by the crystal selection method, can also be used for preparing the single crystal blade by the seed crystal method, and is suitable for batch production. Due to the adoption of the high-strength crystal selector, the integrity of the shell is ensured in the shell preparation process, the single crystal orientation control effect is better, and the qualification rate of the blade can be obviously improved.

Claims (7)

1. A preparation method of a high-strength crystal selector of a single crystal blade is characterized by comprising the following specific steps:
(1) Designing an inner cavity die and an outer shape die of the crystal selector, and processing the inner cavity die and the outer shape die for the crystal selector according to the design structure;
(2) Pressing an inner cavity blank of the crystal selector by using a water-soluble core material through an inner cavity die of the crystal selector;
(3) Putting the inner cavity blank into an outer mold of the crystal selector, and pressing a main body structure of the crystal selector by using a ceramic material by using the outer mold;
(4) Removing the inner cavity blank by using water solution to obtain a wet blank of the crystal selector;
(5) And roasting and strengthening the wet blank of the crystal selector to obtain the crystal selector for the investment casting of the single crystal blade.
2. The method for preparing a high-strength crystal selector of single crystal blades according to claim 1, wherein the diameter of the spiral section of the crystal selector is 1-10 mm, and the pitch of the spiral section is 1-10 mm.
3. The method for preparing the high-strength crystal selector of the single crystal blade as claimed in claim 1, wherein the water-soluble core material is urea core material or gypsum core material.
4. A method for preparing a high-strength crystal selector of single crystal blades as claimed in claim 1, wherein the ceramic material is silicon-based ceramic material or aluminum-based ceramic material.
5. The method for preparing the high-strength single crystal blade crystal selector according to claim 4, wherein the silicon-based ceramic material comprises, by weight, 65-75% of quartz glass powder, 8-10% of fused corundum powder, 15-25% of zirconium silicate powder and 0.5-1.5% of an additive, wherein the additive is magnesium oxide or yttrium oxide.
6. The method for preparing the high-strength crystal selector of the single crystal blade as claimed in claim 4, wherein the aluminum-based ceramic material comprises 68-72% of alumina powder, 26-30% of quartz glass powder and 1-3% of additive by weight, and the additive is magnesium oxide or yttrium oxide.
7. The method for preparing a high-strength crystal selector of a single crystal blade according to claim 1, wherein the firing temperature is 1200-1600 ℃ and the temperature is kept for 2-10 hours.
CN202110409370.0A 2021-04-16 2021-04-16 Preparation method of high-strength crystal selector of single crystal blade Pending CN115213346A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110409370.0A CN115213346A (en) 2021-04-16 2021-04-16 Preparation method of high-strength crystal selector of single crystal blade

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110409370.0A CN115213346A (en) 2021-04-16 2021-04-16 Preparation method of high-strength crystal selector of single crystal blade

Publications (1)

Publication Number Publication Date
CN115213346A true CN115213346A (en) 2022-10-21

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Family Applications (1)

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Country Status (1)

Country Link
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