阅读说明：本技术 一种航空发动机用空心叶片陶瓷型芯矿化剂的制备方法 (Preparation method of hollow blade ceramic core mineralizer for aircraft engine ) 是由 李超 杜应流 叶峰 冯仕歌 于 2020-12-21 设计创作，主要内容包括：本发明公开了一种航空发动机用空心叶片陶瓷型芯矿化剂的制备方法,先将锆英粉高温煅烧4-7h,冷却后机械破碎,在湿法球磨机中与圆锆球一起进行加水球磨,取出悬浮液静置沉淀后排出上层水,把沉淀的锆石粉置于烤箱内烘烤去除水分,搅拌均匀置于密闭容器保存,本发明将矿化剂粉料锆英粉经过了高温煅烧,有效降低参杂的氧化物杂质,让粉料的状态更加稳定；矿化剂锆英粉煅烧后经过湿法球磨机重新进行破碎球磨,获得与陶瓷型芯基体材料粒度相匹配的矿化剂粉料,球磨后矿化剂粒度能很好的和陶芯基体材料相互结合；明显的改善了陶瓷型芯烧结后裂纹现象,同时提高陶瓷型芯的强度和高温抗蠕变性能。(The invention discloses a preparation method of a hollow blade ceramic core mineralizer for an aircraft engine, which comprises the steps of calcining zircon powder at high temperature for 4-7 hours, cooling, mechanically crushing, carrying out water adding and ball milling together with round zircon balls in a wet ball mill, taking out suspension, standing, precipitating, discharging upper water, placing precipitated zircon powder in an oven for baking to remove water, uniformly stirring, and placing in a closed container for storage, wherein the mineralizer powder zircon powder is subjected to high-temperature calcination, so that doped oxide impurities are effectively reduced, and the state of the powder is more stable; after the mineralizer zircon powder is calcined, crushing and ball-milling are carried out again through a wet ball mill to obtain mineralizer powder matched with the granularity of the ceramic core base material, and the mineralizer powder after ball-milling can be well combined with the ceramic core base material; obviously improves the cracking phenomenon of the ceramic core after sintering, and simultaneously improves the strength and the high-temperature creep resistance of the ceramic core.)

1. A preparation method of a hollow blade ceramic core mineralizer for an aircraft engine is characterized by comprising the following steps: the method comprises the following steps:

step one, calcining zircon powder: calcining the ceramic core with mineralizer zircon powder at high temperature for 4-7h, taking out, cooling, and mechanically crushing into small pieces, wherein the size of each small piece of the crushed zircon powder is not more than 20cm³；

Step two, preparation before processing: preparing a wet ball mill, zirconium balls with the diameter of 8-12mm, zirconium balls with the diameter of 3-6mm, an electronic scale, a sealing box, distilled water and calcined and crushed zircon powder;

step three, ball milling: putting zirconium balls, calcined and crushed zircon powder and distilled water into a wet ball mill in sequence according to a proportion of 30% of zircon balls with the diameter of 8-12mm, 40% of zircon balls with the diameter of 3-6mm, 30% of calcined and crushed zircon powder and distilled water, starting the wet ball mill to stir and ball-mill, cooling by adopting circulating cooling water at the same time, discharging zircon powder mineralizing agent suspension, and then standing and precipitating;

step four, suspension treatment: placing the zircon powder mineralizing agent suspension in a standing barrel, standing for 48-72 hours, discharging upper-layer liquid water after precipitation and powder-liquid separation appear at the bottom of the standing barrel, and then shoveling zircon powder material at the bottom of the standing barrel into an enamel tray and immediately feeding the enamel tray into an oven for baking;

step five, storage: and after the moisture in the zircon powder is baked and discharged, powering off the oven, cooling the zircon powder to room temperature along with the oven, uniformly stirring the zircon powder, and storing the zircon powder in a sealing box for later use.

2. The method for preparing the ceramic core mineralizer for the hollow blade of the aircraft engine according to claim 1, wherein the method comprises the following steps: the calcination temperature in the first step is 1540-1580 ℃.

3. The method for preparing the ceramic core mineralizer for the hollow blade of the aircraft engine according to claim 1, wherein the method comprises the following steps: the wet ball mill comprises a frame, the side face of the frame is connected with a ball milling barrel through a side support, an upper cover is installed on the upper end face of the ball milling barrel, a stepless speed change motor is installed on the frame and connected with a stirring shaft through a coupler, the stirring shaft movably penetrates through the upper cover to be arranged in the ball milling barrel, stirring blades are installed on the stirring shaft, a discharge valve is arranged on the lower end face of the ball milling barrel, and a power switch is installed on the side face of the frame.

4. The method for preparing the ceramic core mineralizer for the hollow blades of the aircraft engine according to claim 3, wherein the method comprises the following steps: and the side surfaces of the upper end and the lower end of the ball milling barrel are respectively provided with a cooling water outlet and a cooling water inlet.

5. The method for preparing the ceramic core mineralizer for the hollow blades of the aircraft engine according to claim 3, wherein the method comprises the following steps: the inner wall of the ball milling barrel and the outer wall of the stirring paddle are both coated with polyurethane rubber, and the upper cover is made of polyurethane rubber.

6. The method for preparing the ceramic core mineralizer for the hollow blade of the aircraft engine according to claim 1, wherein the method comprises the following steps: and in the third step, zircon balls with the diameter of 8-12mm, zircon balls with the diameter of 3-6mm, calcined and crushed zircon powder and distilled water are sequentially added into a wet ball mill, and the zircon powder is submerged by the addition of the distilled water.

7. The method for preparing the ceramic core mineralizer for the hollow blade of the aircraft engine according to claim 1, wherein the method comprises the following steps: in the fourth step, the baking temperature is 150-.

Technical Field

The invention relates to the technical field of ceramic core manufacturing and production, in particular to a preparation method of a hollow blade ceramic core mineralizer for an aeroengine.

Background

With the increasing performance of aircraft engines, turbine blades located at key positions are mostly of hollow structures in order to be able to withstand higher temperatures and more severe use environments, the ceramic core is an essential link for forming the complex cavity of the hollow blade, so that the ceramic core not only meets the requirement of precise dimensional precision of the inner cavity of the hollow blade, meanwhile, when the investment casting is used, the investment casting needs to bear high pressure and impact dewaxing of high-speed wax liquid, the investment casting needs to bear mechanical impact and thermal impact of molten metal when hot water and steam are used for pouring under the action of high temperature for a long time during the roasting of a cooking shell, the addition of a proper amount of mineralizer can reduce the sintering temperature of the core, reduce the sintering time, simultaneously maintain or improve the comprehensive performance of the ceramic core, and the added mineralizer interacts with the base material to promote the crystal lattice activation and further generate a solid solution; or the mineralizer is converted into liquid phase at the sintering temperature to bond the base material; or prevent the substrate material from polycrystalline conversion, which is beneficial to sintering. The zircon powder is one of common mineralizers, and has the advantages that the melting point of the zircon powder is as high as 2500 ℃, the zircon powder has an inhibiting effect on viscous flow of quartz glass under a high-temperature condition, in addition, the Zr4+ does not influence the devitrification process of the quartz glass, a large amount of cristobalite crystals can be formed on the core in the early stage of the injection burning stage to be offset with creep deformation of the quartz glass, and the high-temperature deformation resistance of the ceramic core is further improved.

The traditional mineralizer material is not calcined at high temperature, some impurity elements exist in the mineralizer, the state is unstable, the sintering process of the ceramic core is influenced, the mineralizer cannot react with a base material sufficiently to generate a stable solid solution, meanwhile, the granularity of the mineralizer which is not processed cannot be matched with the base material well, the mutual adhesion with the base material at the sintering temperature of the ceramic core is also influenced, and finally, the defects of crack, low strength and poor high-temperature deformation resistance after the ceramic core is sintered are caused.

Disclosure of Invention

The invention mainly aims to provide a preparation method of a hollow blade ceramic core mineralizer for an aeroengine, which can effectively solve the problems in the background technology.

In order to achieve the purpose, the invention adopts the technical scheme that: a preparation method of a hollow blade ceramic core mineralizer for an aircraft engine comprises the following steps:

step one, calcining zircon powder: calcining the ceramic core with mineralizer zircon powder at high temperature for 4-7h, taking out, cooling, and mechanically crushing into small pieces, wherein the size of each small piece of the crushed zircon powder is not more than 20cm³；

Step two, preparation before processing: preparing a wet ball mill, zirconium balls with the diameter of 8-12mm, zirconium balls with the diameter of 3-6mm, an electronic scale, a sealing box, distilled water and calcined and crushed zircon powder;

step three, ball milling: putting zirconium balls, calcined and crushed zircon powder and distilled water into a wet ball mill in sequence according to a proportion of 30% of zircon balls with the diameter of 8-12mm, 40% of zircon balls with the diameter of 3-6mm, 30% of calcined and crushed zircon powder and distilled water, starting the wet ball mill to stir and ball-mill, cooling by adopting circulating cooling water at the same time, discharging zircon powder mineralizing agent suspension, and then standing and precipitating;

step four, suspension treatment: placing the zircon powder mineralizing agent suspension in a standing barrel, standing for 48-72 hours, discharging upper-layer liquid water after precipitation and powder-liquid separation appear at the bottom of the standing barrel, and then shoveling zircon powder material at the bottom of the standing barrel into an enamel tray and immediately feeding the enamel tray into an oven for baking;

step five, storage: and after the moisture in the zircon powder is baked and discharged, powering off the oven, cooling the zircon powder to room temperature along with the oven, uniformly stirring the zircon powder, and storing the zircon powder in a sealing box for later use.

Preferably, the calcination temperature in the first step is 1540-1580 ℃.

Preferably, the wet ball mill comprises a frame, the side of the frame is connected with a ball milling barrel through a side support, an upper cover is installed on the upper end face of the ball milling barrel, a stepless speed change motor is installed on the frame, the stepless speed change motor is connected with a stirring shaft through a coupler, the stirring shaft movably penetrates through the upper cover to be arranged in the ball milling barrel, stirring blades are installed on the stirring shaft, a discharge valve is arranged on the lower end face of the ball milling barrel, and a power switch is installed on the side face of the frame.

Preferably, the side surfaces of the upper end and the lower end of the ball milling barrel are respectively provided with a cooling water outlet and a cooling water inlet.

Preferably, the inner wall of the ball milling barrel and the outer wall of the stirring paddle are both coated with polyurethane rubber, and the upper cover is made of polyurethane rubber.

Preferably, in the third step, zircon balls with the diameter of 8-12mm, zircon balls with the diameter of 3-6mm, calcined and crushed zircon powder and distilled water are sequentially added into a wet ball mill, and the zircon powder is submerged by the addition of the distilled water.

Preferably, the baking temperature in the fourth step is 150-.

Compared with the prior art, the invention has the following beneficial effects: according to the invention, the mineralizer powder zircon powder is subjected to high-temperature calcination, the calcination temperature and the calcination time are controllable, and oxide impurities such as Fe2O3 and the like doped in the zircon powder are effectively reduced, so that the state of the powder is more stable; the mineralizer zircon powder is calcined and then crushed and ball-milled again by a wet ball mill, the ball milling medium, time and temperature are all controllable, mineralizer powder matched with the granularity of the ceramic core base material is obtained, and the mineralizer powder after ball milling can be well combined with the ceramic core base material; obviously improves the crack phenomenon of the ceramic core after sintering and also improves the strength and the high-temperature creep resistance of the ceramic core.

Drawings

Fig. 1 is a schematic structural diagram of a wet ball mill according to the present invention.

In the figure: 1. a continuously variable transmission motor; 2. a coupling; 3. a stirring shaft; 4. an upper cover; 5. a ball milling barrel; 6. a cooling water outlet; 7. a stirring paddle; 8. a cooling water inlet; 9. a discharge valve; 10. a power switch; 11. a frame; 12. side brackets.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.

A preparation method of a hollow blade ceramic core mineralizer for an aircraft engine comprises the following steps:

step one, calcining zircon powder: calcining the ceramic core with mineralizer zircon powder at 1540-1580 ℃ for 4-7h at 1540-1580 ℃, taking out, cooling, and mechanically crushing into small pieces, wherein the size of each small piece of the crushed zircon powder is not more than 20cm³；

Step two, preparation before processing: preparing a wet ball mill, zirconium balls with the diameter of 8-12mm, zirconium balls with the diameter of 3-6mm, an electronic scale, a sealing box, distilled water and calcined and crushed zircon powder;

step three, ball milling: putting zirconium balls, calcined and crushed zircon powder and distilled water into a wet ball mill in proportion, wherein the proportion is 30% of zircon balls with the diameter of 8-12mm, 40% of zircon balls with the diameter of 3-6mm, 30% of calcined and crushed zircon powder and distilled water, weighing accurate mass by using an electronic scale, and adding the zircon balls with the diameter of 8-12mm, 3-6mm, the calcined and crushed zircon powder and the distilled water into the wet ball mill in sequence, wherein the adding amount of the distilled water submerges the zircon powder, starting the wet ball mill to stir and ball-mill, cooling by adopting circulating cooling water, preventing the barrel from overheating in the stirring and ball-milling process, stirring and ball-milling for 50-60min, discharging zircon powder mineralizing agent suspension, standing and precipitating;

step four, suspension treatment: placing the zircon powder mineralizing agent suspension in a standing barrel, standing for 48-72 hours, discharging upper-layer liquid water after precipitation and powder-liquid separation appear at the bottom of the standing barrel, shoveling zircon powder material at the bottom of the standing barrel into an enamel tray, immediately sending the zircon powder material into an oven for baking at the baking temperature of 150-;

step five, storage: after moisture in the zircon powder is baked and discharged, the zircon powder is uniformly stirred and placed in a sealing box for storage after the zircon powder is cooled to room temperature along with the baking oven after the baking oven is powered off, and in order to be well combined with the ceramic core base material, the zircon powder is cooled and then sieved to obtain a mineralizer, namely the zircon powder with the granularity of 360-mesh and 450-mesh.

In the embodiment, as shown in fig. 1, the wet ball mill includes a frame 11, the side surface of the frame 11 is connected to the ball mill barrel 5 through a side bracket 12, the upper end surface of the ball milling barrel 5 is provided with an upper cover 4, the stander 11 is provided with a stepless speed change motor 1, the stepless speed change motor 1 is connected with a stirring shaft 3 through a coupler 2, the stirring shaft 3 movably penetrates through an upper cover 4 and is arranged in a ball milling barrel 5, a stirring blade 7 is arranged on the stirring shaft 3, a discharge valve 9 is arranged on the lower end surface of the ball milling barrel 5, a power switch 10 is arranged on the side surface of the frame 11, the side surfaces of the upper end and the lower end of the ball milling barrel 5 are respectively provided with a cooling water outlet 6 and a cooling water inlet 8, the ball milling device is used for adding water to prevent overheating in the ball milling barrel 5 in the process of stirring and ball milling, the inner wall of the ball milling barrel 5 and the outer wall of the stirring paddle blade 7 are both coated with polyurethane rubber, and the upper cover 4 is made of polyurethane rubber.

While certain exemplary embodiments of the present invention have been described above by way of illustration only, it will be apparent to those of ordinary skill in the art that the described embodiments may be modified in various different ways without departing from the spirit and scope of the invention. Accordingly, the drawings and description are illustrative in nature and should not be construed as limiting the scope of the invention.