阅读说明：本技术 大型高温合金机匣铸件快速充型浇冒系统及浇注方法 (Rapid mold filling pouring system and pouring method for large-scale high-temperature alloy casing casting ) 是由 康茂东 陈基东 郜亚洲 王俊 王国祥 李建中 高海燕 孙宝德 于 2021-10-14 设计创作，主要内容包括：本发明提供一种大型高温合金机匣铸件快速充型浇冒系统及浇注方法,包括：承接浇注液的浇口杯；直浇道,其进口与浇口杯的底部连通；陶瓷挡渣网,设置在直浇道和浇口杯之间；多个补缩模组,设置在机匣铸件上侧,用于对机匣铸件进行凝固过程补缩；横浇道,位于多个补缩模组之间,连通多个补缩模组。本发明上述浇冒系统和浇注方法,摒弃了传统上大型高温合金机匣铸件的上下双环形横浇道设计和底注式充型方式,减少了充填复杂浇冒系统的金属液,提供了工艺出品率的同时,还能够确保金属熔体快速充填机匣铸件整个型腔和减少热量损失,熔体前沿仅有一次交汇机会,能够大幅减少熔体多头交汇对冲产生的氧化膜缺陷,显著提高了铸件冶金质量。(The invention provides a rapid mold filling pouring system and a pouring method for a large-scale high-temperature alloy casing casting, which comprises the following steps: a pouring cup for receiving pouring liquid; the inlet of the sprue is communicated with the bottom of the sprue cup; the ceramic slag blocking net is arranged between the sprue and the sprue cup; the feeding modules are arranged on the upper side of the casing casting and are used for feeding the casing casting in the solidification process; and the cross gate is positioned among the feeding modules and communicated with the feeding modules. The casting system and the casting method of the invention abandon the upper and lower double annular cross gate design and the bottom pouring type filling mode of the traditional large-scale high-temperature alloy casing casting, reduce the metal liquid for filling the complex casting system, provide the process yield, ensure that the metal melt can quickly fill the whole cavity of the casing casting and reduce the heat loss, have only one intersection chance at the front edge of the melt, greatly reduce the oxide film defect generated by multi-head intersection hedging of the melt, and obviously improve the metallurgical quality of the casting.)

1. A large-scale superalloy casing casting rapid mold filling type pouring system is characterized by comprising:

a pouring cup for receiving pouring liquid;

the inlet of the sprue is communicated with the bottom of the sprue cup;

the ceramic slag blocking net is arranged between the sprue and the sprue cup;

the feeding modules are arranged on the upper side of the casing casting and are used for feeding the casing casting in a solidification process;

and the cross gate is positioned among the feeding modules and is communicated with the feeding modules.

2. The rapid filling runner system of large superalloy case casting of claim 1, wherein the sprue cup is an inverted frustoconical sprue cup, a lower circle of the inverted frustoconical sprue cup is the same as the sprue diameter, an upper circle of the inverted frustoconical sprue cup is 2-3 times the sprue diameter, and a height of the inverted frustoconical sprue cup is 1.5-3 times the lower circle diameter.

3. The large superalloy casing casting rapid-filling pouring system according to claim 1, wherein the sprue is one of the plurality of feeding modules, wherein the feeding module with the highest modulus is selected as the sprue.

4. The rapid filling and running system for large-scale superalloy casing castings according to claim 3, wherein a modulus of a single feeding module is 1.5-2 times a modulus of a corresponding portion of the casing casting.

5. The rapid filling and running system for large-sized superalloy casing castings according to claim 1, wherein the feeding module is disposed on an upper side of a thick-walled flange of the casing casting, the thin-walled flange of the casing casting is disposed on a bottom side, and the thick-walled flange is disposed on an upper side.

6. The large superalloy casing casting fast-fill runner system of any of claims 1 to 5, further comprising a wedge structure, wherein the feeding module is connected to the casing casting by the wedge structure.

7. The large superalloy casing casting rapid-filling pouring system according to claim 6, wherein the wedge structure comprises a wedge piece arranged at a lower end of the feeding module, and a socket piece arranged on the casing casting and matched with the wedge piece, wherein the wedge piece is inserted into the socket piece to achieve communication between the feeding module and the casing casting.

8. A pouring method using the rapid filling and running system for large superalloy casing castings according to any of claims 1 to 7, comprising:

assembling a rigging system that employs a large superalloy case casting rapid fill rigging system of any of claims 1-7;

preparing a large-scale high-temperature alloy casing casting shell, roasting and preheating the shell, smelting high-temperature alloy and adopting the pouring system for pouring and molding;

and after casting molding and cooling, cutting the casting system to obtain the large-scale high-temperature alloy casing casting.

9. The method of claim 8, wherein the casting is performed by a technique that controls the effective mass of the critical casting, wherein:

thermodynamic software is adopted to calculate the liquidus temperature and the shrinkage coefficient of the high-temperature alloy, the pouring temperature of the high-temperature alloy is liquidus temperature + (200-: (casting volume + dense feeding module volume + cross gate volume + sprue volume) x the high-temperature alloy density at room temperature, and the actual pouring amount in the pouring process is the critical pouring effective mass +/-1 kg.

10. The method of pouring for a large superalloy casing casting rapid fill system as claimed in claim 8, wherein the casting is shaped wherein: the heating magnesium powder is added in the feeding module to prolong the solidification time and enhance the feeding effect of the feeding module on the casing casting.

Technical Field

The invention relates to the field of high-temperature alloy precision casting, in particular to a rapid mold filling pouring system and a pouring method for a large-scale high-temperature alloy casing casting.

Background

The large-scale casing component is one of main bearing structures of an aeroengine, and can be classified into a titanium alloy casing and a high-temperature alloy casing according to the temperature bearing capacity and the service load requirement. In engineering, a titanium alloy casing is usually formed by centrifugal casting precision, the design of a casting system is relatively simple, and the macro segregation of elements is very easy to occur in high-temperature alloy under the action of centrifugal force, so that the forming mode mainly adopts gravity precision casting. Through the literature search of the prior art, the following findings are found: the Chinese invention patent with the application number of 202010703005.6 relates to a bottom pouring type pouring system and a pouring method for a large-scale high-temperature alloy casing casting, and provides the bottom pouring type pouring system and the pouring method for the large-scale high-temperature alloy casing casting, wherein the system comprises a sprue cup, a sprue and a pouring mechanism communicated with the sprue, and the pouring mechanism is connected with an outer ring and an inner ring of the casting; the method comprises the steps of guiding the casting liquid to the casting feeding mechanism through the drainage device, respectively carrying out mold filling and feeding on the casting from the upper end and the bottom end of the casting through the casting feeding mechanism so as to transfer the stress of the inner ring and the outer ring of the casting, and simultaneously carrying out mold filling and feeding on the outer wall of the casting from top to bottom through the casting feeding mechanism so as to complete the casting of the high-temperature alloy casing casting. The bottom pouring type pouring system provided by the invention better solves the problem of turbulence in the pouring process of a large casting, and can be applied to precise forming of a part of low-grade high-temperature alloy materials. However, the gating system design increases the flow before melt filling, and the distributed ingate design is also not beneficial to melt rapid filling. Therefore, it is difficult to apply the method to precision molding of high-temperature alloys having a large interval between crystallization temperatures.

Through retrieval, the optimization design and application verification of a power turbine casing investment casting system are reported in the 417 pages 414-and-fro 417 of the No. 4 volume 39 of special casting and non-ferrous alloy in 2019 of Houzhengqian et al, an inner filling type and half-wrapping type pouring system is designed, and the problem of macroscopic shrinkage cavity and shrinkage porosity of casing castings is solved. However, the design of the cast-up system has a plurality of metal liquid flows which are opposite to each other, so that the defect of oxide film is easily generated, the fatigue performance of the casing casting is reduced, and when the cast-up system is applied to the development of the casing casting of a high-performance aircraft engine, the design of the cast-up system needs to be further optimized to improve the long-term service reliability.

Disclosure of Invention

Aiming at the defects of the design and the pouring method of the pouring system of the existing large-scale high-temperature alloy casing casting, the invention aims to provide a rapid filling type pouring system and a rapid filling type pouring method of the large-scale high-temperature alloy casing casting.

According to one aspect of the invention, a large superalloy casing casting rapid-filling type pouring system is provided, comprising:

a pouring cup for receiving pouring liquid;

the inlet of the sprue is communicated with the bottom of the sprue cup;

the ceramic slag blocking net is arranged between the sprue and the sprue cup;

the feeding modules are arranged on the upper side of the casing casting and are used for feeding the casing casting in a solidification process;

and the cross gate is positioned among the feeding modules and is communicated with the feeding modules.

Preferably, the pouring cup is an inverted circular truncated cone type pouring cup, the diameter of the lower circle of the inverted circular truncated cone type pouring cup is the same as that of the sprue, the diameter of the upper circle of the inverted circular truncated cone type pouring cup is 2-3 times that of the sprue, and the height of the inverted circular truncated cone type pouring cup is 1.5-3 times that of the lower circle of the inverted circular truncated cone type pouring cup.

Preferably, the sprue may be one of a plurality of feeding modules, and in particular, one of the dense feeding modules with the largest modulus is selected as the sprue. The feeding modules are vertically arranged according to the shape of the casing casting to form a dense feeding module. The modulus of a single feeding module is 1.5-2 times of the modulus of the corresponding part of the casing casting.

Preferably, the pouring system further comprises a wedge structure, and the feeding module is connected with the casing casting through the wedge structure.

Preferably, the feeding module is arranged on the upper side of a thick-wall flange of the casing casting, the thin-wall flange of the casing casting is placed on the bottom side, and the thick-wall flange is placed on the upper side.

According to another aspect of the invention, a pouring method adopting the rapid filling type pouring system for the large-scale high-temperature alloy casing casting is also provided, and comprises the following steps:

assembling a pouring system, wherein the pouring system adopts the rapid filling type pouring system for the large-scale high-temperature alloy casing casting;

preparing a large-scale high-temperature alloy casing casting shell, roasting and preheating the shell, smelting high-temperature alloy and adopting the pouring system for pouring and molding;

and after casting molding and cooling, cutting the casting system to obtain the large-scale high-temperature alloy casing casting.

Preferably, the casting molding adopts a technology for controlling the effective mass of the critical casting, wherein:

thermodynamic software is adopted to calculate the liquidus temperature and the shrinkage coefficient of the high-temperature alloy, the pouring temperature of the high-temperature alloy is liquidus temperature + (200-: (casting volume + dense feeding module volume + cross gate volume + sprue volume) x the high-temperature alloy density at room temperature, and the actual pouring amount in the pouring process is the critical pouring effective mass +/-1 kg.

Preferably, the cast molding, wherein: the heating magnesium powder is added in the feeding module to prolong the solidification time and enhance the feeding effect of the feeding module on the casing casting.

In the invention, in the casting molding, if the casting quality is less than the critical effective casting quality, the casting is not sufficiently fed, and the casting has the defects of shrinkage cavity and shrinkage porosity; more than the critical effective pouring quality, a large amount of molten metal exists in a cross gate at the later stage of solidification, and inward tension is formed during solidification shrinkage, so that the casing is deformed non-uniformly, and the dimensional accuracy is reduced. The present invention provides a technique for controlling the effective quality of a critical pour that can advantageously overcome the above-mentioned problems.

Compared with the prior art, the invention has the following beneficial effects:

the pouring system and the pouring method of the invention abandon the upper and lower double annular cross gate design and the bottom pouring type filling mode of the traditional large high-temperature alloy casing casting, reduce the metal liquid for filling the complex pouring system, provide the process yield, ensure that the metal melt can quickly fill the whole cavity of the casing casting and reduce the heat loss, have only one intersection chance at the front edge of the melt, greatly reduce the oxide film defect generated by multi-head intersection hedging of the melt, obviously improve the metallurgical quality of the casting, have obvious economic benefits, and have the advantages that the design of the existing large high-temperature alloy casing casting pouring system cannot be compared with the design.

The casting system and the casting method can provide support for developing high-grade high-temperature alloy large-scale casing castings with large crystallization temperature intervals and high casting temperatures, and provide a solution for a casting engineer to develop the design of the casting system of the large-scale casing castings.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:

FIG. 1 is a schematic diagram of a system architecture for a rigging according to an embodiment of the present invention;

FIG. 2 is a cross-sectional view of a rigging system according to an embodiment of the present invention;

in the figure: a large high-temperature alloy casing casting 1; a thin-walled flange 2; a thick-walled flange 3; a feeding module 4; a wedge-shaped structure 5; a cross gate 6; a sprue 7; an inverted circular truncated cone-shaped pouring cup 8; a ceramic slag trap net 9.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that variations and modifications can be made by persons skilled in the art without departing from the spirit of the invention. All falling within the scope of the present invention.

FIG. 1 is a schematic diagram of a system architecture for a rigging according to an embodiment of the present invention; FIG. 2 is a cross-sectional view of a rigging system in accordance with an embodiment of the present invention.

As shown in fig. 1 and 2, the present embodiment provides a rapid-filling type pouring system for large-scale superalloy casing castings, which includes: the casting device comprises a pouring cup 8, a cross runner 6, a sprue 7, a ceramic slag blocking net 9 and a plurality of feeding modules 4, wherein the pouring cup 8 is used for receiving pouring liquid; the inlet of the sprue 7 is communicated with the bottom of the pouring cup 8; the ceramic slag blocking net 9 is arranged between the sprue 7 and the pouring cup 8; the feeding modules 4 are arranged on the upper side of the casing casting 1 and are used for feeding the casing casting 1 in the solidification process; the runner 6 is located between the feeding modules 4 and communicates the feeding modules 4.

The pouring system in the embodiment abandons the upper and lower double-ring cross gate design and the bottom pouring type filling mode of the traditional large-scale high-temperature alloy casing casting, and reduces the metal liquid filled in the complex pouring system.

In some embodiments, when the pouring system design of the large-scale high-temperature alloy casing casting 1 is carried out, the thin-wall flange 2 of the casing casting is placed on the bottom side, and the thick-wall flange 3 is placed on the upper side. And feeding modules 4 are densely arranged on the upper side of the thick-wall flange 3 to feed the casing casting 1 in the solidification process, and the modulus of each feeding module 4 is 1.5-2 times that of the corresponding part of the casing casting 1.

Referring to fig. 1, in some embodiments, the feeding modules 4 are connected by a cross-runner 6, and the cross-runner 6 is cylindrical and has a diameter 0.5 times that of the dense feeding modules. Further, one of the dense feeding modules with the largest modulus is preferably selected as the sprue 7 based on the modulus calculation of each part of the casing casting 1.

Referring to fig. 2, in some embodiments, the inverted circular truncated cone type pouring cup 8 is connected to the sprue 7, the lower circle of the inverted circular truncated cone type pouring cup 8 has the same diameter as the sprue 7, the diameter of the upper circle is 2-3 times of the diameter of the sprue 7, and the height of the inverted circular truncated cone type pouring cup 8 is 1.5-3 times of the diameter of the lower circle. A ceramic slag blocking net 9 is arranged between the sprue 7 and the inverted round platform type sprue cup 8, and has the functions of removing slag and stabilizing metal fluid.

In some embodiments, the dense feeding modules 4 are connected to the casing casting 1 through a wedge structure 5, as shown in fig. 2, the wedge structure 5 includes a wedge member disposed at a lower end of each feeding module 4, and a socket member disposed on the casing casting 1 and corresponding to each wedge member, and the wedge member is inserted into the socket member to communicate the feeding modules 4 with the casing casting 1.

In the embodiment of the invention, the design idea of the pouring system is eliminated, the upper and lower double-ring cross runners of the traditional casing casting are designed, the process yield is improved, the metal melt can be ensured to quickly fill the whole cavity of the casing casting, the heat loss is reduced, only one melt intersection opportunity is provided, the oxide film defect caused by multi-head intersection hedging of the melt can be greatly reduced, and the metallurgical quality of the casting is obviously improved.

According to the pouring system, wax molds of a pressing casing casting 1, a feeding module 4, a cross gate 6, a wedge-shaped structure 5, a straight gate 7 and an inverted circular truncated cone type pouring cup 8 are designed, and the pouring system is assembled according to the design. Thermodynamic software is adopted to calculate the liquidus temperature and the shrinkage coefficient of the high-temperature alloy, the casting temperature of the high-temperature alloy is the liquidus temperature plus 200-300 ℃, the total amount of the cast high-temperature alloy is the critical effective mass, and the specific amount is as follows: the casting volume, the volume of the dense feeding module, the volume of the cross gate, the volume of the straight gate and the density of the high-temperature alloy at room temperature are multiplied, and the actual pouring amount in the pouring process is the critical effective pouring mass +/-1 kg. The dense feeding module 4 is internally added with heating magnesium powder to prolong the solidification time of the dense feeding module and enhance the feeding effect of the dense feeding module on casing castings. The technical advantage of controlling the critical effective pouring quality is that the critical effective pouring quality is less than the critical effective pouring quality, so that the feeding of the casting is insufficient, and the defects of shrinkage cavity and shrinkage porosity appear in the casting; more than the critical effective pouring quality, a large amount of molten metal exists in a cross gate at the later stage of solidification, and inward tension is formed during solidification shrinkage, so that the casing is deformed non-uniformly, and the dimensional accuracy is reduced. After casting molding and cooling, the casting system is cut, and then the large-scale high-temperature alloy casing casting with high dimensional precision and excellent internal quality can be obtained.

To better illustrate the above described embodiments of the invention, the following description is made in conjunction with specific alloys and casing components:

example 1: the large-scale high-temperature alloy casing component of a certain aeroengine has the diameter of 970mm, the height of 200mm and the minimum wall thickness of 5 mm. According to the service requirement, the K447A high-temperature alloy is selected, because the content of the K447A high-temperature alloy gamma' is 64.31%, the welding repair performance is extremely poor, the high-temperature alloy cannot be formed by additive manufacturing, and only can be integrally and precisely formed at one time by a precise casting technology. Firstly, a large-sized casing casting wax mold is developed by an MPI wax pressing machine, the casting wax mold is flatly placed on a marble workbench, a thin-wall flange of the casing casting is placed on the bottom side, and a thick-wall flange is placed on the upper side, so that a sequential solidification mode from bottom to top is formed in the solidification process. 19 feeding modules are densely arranged on the upper side of the thick-wall flange, wherein the diameter of 17 feeding modules is 38mm, the diameter of 2 feeding modules is 23mm, and the casing casting is fully fed in the solidification process. The dense feeding module is connected with the casing casting through a wedge-shaped structure, and the dense feeding module is connected with the casing casting through a cross gate with the diameter of 15 mm. Based on the modulus calculation of each part of the casing casting, the diameter of the selected sprue is 50mm, the sprue is connected with an inverted circular truncated cone type sprue cup, the diameter of the upper circular truncated cone is 120mm, and the height of the circular truncated cone is 60 mm.

After the pouring system is assembled according to the design, the concrete pouring method is to adopt the traditional silica sol slurry-cementing sand-spraying method to prepare the large-scale thin-wall high-temperature alloy hollow casing casting shell, roast the shell for 24 hours, preheat the shell to 1000 ℃, smelt K447A high-temperature alloy and perform pouring molding. After calculating the liquidus temperature of the high-temperature alloy as a shrinkage coefficient by adopting JMatPro thermodynamic software, determining the pouring temperature of the K447A high-temperature alloy of 1530 ℃ and calculating the critical effective weight of 220 Kg. And after the casting molding is cooled for 24 hours, a casting system is cut, the internal quality is found to be good, and the dimensional accuracy of the large-scale high-temperature alloy casing casting is evaluated to reach the CT5 grade through three-coordinate measurement and is superior to the technical index requirement.

Example 2:

the large-scale high-temperature alloy casing component of a certain aeroengine has the diameter of 1050mm, the height of 220mm and the minimum wall thickness of 3 mm. According to the service requirement, the selected material IC10 high-temperature alloy has large brittleness because the content of gamma' of the IC10 high-temperature alloy is 69.44%, and the traditional repair welding method can not repair welding and shape correction and can only be integrally and precisely formed at one time by a precise casting technology.

Firstly, a large-sized casing casting wax mold is developed by an MPI wax pressing machine, the casting wax mold is flatly placed on a marble workbench, a thin-wall flange of the casing casting is placed on the bottom side, and a thick-wall flange is placed on the upper side, so that a sequential solidification mode from bottom to top is formed in the solidification process. The thick wall flange upside is intensive arranges 23 feeding modules, and feeding module diameter is 42mm, realizes carrying out the full feeding of solidification process to the quick-witted casket foundry goods. The dense feeding module is connected with the casing casting through a wedge-shaped structure, and the dense feeding module is connected with the casing casting through a cross gate with the diameter of 20 mm. Based on the modulus calculation of each part of the casing casting, the diameter of the selected sprue is 60mm, the sprue is connected with an inverted circular truncated cone type sprue cup, the diameter of the upper circular truncated cone is 150mm, and the height of the circular truncated cone is 90 mm.

After the pouring system is assembled according to the design, the concrete pouring method is to adopt the traditional silica sol slurry-cementing sand-spraying method to prepare the large-scale thin-wall high-temperature alloy hollow casing casting shell, roast the shell for 24 hours and preheat to 1000 ℃, smelt the IC10 high-temperature alloy and perform pouring molding. After calculating the liquidus temperature of the high-temperature alloy as a shrinkage coefficient by adopting JMatPro thermodynamic software, determining the pouring temperature of the IC10 high-temperature alloy to be 1550 ℃, and calculating the critical effective weight to be 310 Kg. After the casting molding is cooled for 24 hours, a casting system is cut, the internal quality is found to be good, the dimensional accuracy of the large-scale high-temperature alloy casing casting is evaluated to reach the CT5 level through three-coordinate measurement, the technical index requirement is met, and the invention is verified to be suitable for developing high-grade high-temperature alloy precision castings which are difficult to repair weld and modify.

The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes and modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The above-described preferred features may be used in any combination without conflict with each other.