阅读说明：本技术 一种去除高温合金粉末中非金属夹杂的装置及其方法 (Device and method for removing non-metal impurities in high-temperature alloy powder ) 是由 宋嘉明 罗成 瞿宗宏 陈富璐 吴纪 张妍莉 赖运金 梁书锦 于 2021-09-08 设计创作，主要内容包括：本发明公开了一种去除高温合金粉末中非金属夹杂的装置及其方法,包括静电分离室,其下粉口处设有送粉单元,静电分离室上端分别开设有与真空系统连接的抽气口和与惰性气体系统连接的充气口,内部设静电分离机构,用于分离含有非金属夹杂的粉末,并将分离后的非金属夹杂存储于废粉收集罐中、金属粉末存储于合格粉收集罐中；还设计了基于上述装置的方法。本发明通过结构优化,避免了常规静电分离过程中的离心力作用,使得电场的库仑力以及挡板的镜面吸力更好的作用在非金属夹杂上,粉末仅在重力作用下发生滚动,使得非金属夹杂,尤其是粘连金属粉末的异常非金属夹杂能够更好的粘附在挡板上而被毛刷清理至废粉区。(The invention discloses a device and a method for removing non-metallic impurities in high-temperature alloy powder, and the device comprises an electrostatic separation chamber, wherein a powder feeding unit is arranged at the lower powder opening of the electrostatic separation chamber, the upper end of the electrostatic separation chamber is respectively provided with an air suction opening connected with a vacuum system and an air charging opening connected with an inert gas system, and an electrostatic separation mechanism is arranged inside the electrostatic separation chamber and is used for separating powder containing the non-metallic impurities, storing the separated non-metallic impurities in a waste powder collection tank, and storing metal powder in a qualified powder collection tank; a method based on the device is also designed. According to the invention, through structural optimization, the centrifugal force action in the conventional electrostatic separation process is avoided, so that the coulomb force of an electric field and the mirror surface suction force of the baffle plate can better act on the non-metal impurities, and the powder rolls only under the action of gravity, so that the non-metal impurities, especially the abnormal non-metal impurities adhered with the metal powder, can be better adhered to the baffle plate and are cleaned to a waste powder area by the brush.)

1. A device for removing non-metal inclusions in high-temperature alloy powder comprises an electrostatic separation chamber (2), a powder feeding unit (1) is connected with a powder outlet at the top of the electrostatic separation chamber (2), it is characterized in that the upper end of the electrostatic separation chamber (2) is respectively provided with an air suction port (21) and an air charging port (22), the extraction opening (21) is connected with a vacuum system, the inflation opening (22) is connected with an inert gas system, the electrostatic separation chamber (2) is internally provided with an electrostatic separation mechanism (23), a waste powder collecting tank (24) and a qualified powder collecting tank (25) are arranged below the electrostatic separation chamber (2), the electrostatic separation mechanism (23) is used for separating powder containing non-metal impurities, the separated non-metal impurities are stored in a waste powder collecting tank (24), and the separated metal powder is stored in a qualified powder collecting tank (25);

the electrostatic separation mechanism (23) comprises a corona electrode array (231), a baffle (232) and a brush (233), the baffle (232) is located below the corona electrode array (231), one end of the baffle (232) is fixedly connected with a rotating shaft (234), and the other end of the baffle (232) is located at the upper position and the lower position of a horizontal plane where the axis of the rotating shaft (234) is located and is respectively provided with an upper limiting block (235) and a lower limiting block (236); send whitewashed unit (1) and corona electrode array (231) to open when baffle (232) rotates last stopper (235), rotate and close when stopper (236) down in baffle (232), when baffle (232) rotate last stopper (235), the lowest of baffle (232) is located the top of qualified powder collection tank (25) or the top of a set of baffle down, when baffle (232) rotate to stopper (236) down, the lowest of baffle (232) is located the top of useless powder collection tank (24), and fall to useless powder collection tank (24) through the adsorbed non-metallic brush on brush (233) with baffle (232).

2. The device for removing the non-metallic inclusions in the high-temperature alloy powder is characterized in that the electrostatic separation mechanism (23) further comprises a guide rail (237), the guide rail (237) is arranged above the lower limit block (236) of the baffle plate (232) in parallel, the brush (233) is movably arranged on the guide rail (237) through a slide block, and the slide block is driven by a moving motor to enable the brush (233) to reciprocate on the guide rail (237);

the brush (233) is provided on a brush roller, and the brush roller is driven by a rotating motor to rotate the brush (233) along with the brush roller.

3. The apparatus for removing non-metallic inclusions from a superalloy powder as in claim 1, wherein the corona electrode array (231) consists essentially of 4 to 5 high voltage electrodes arranged in parallel.

4. The device for removing the non-metal impurities in the high-temperature alloy powder is characterized in that a plurality of grooves are formed in one end, far away from the rotating shaft (234), of the baffle plate (232) at intervals in the vertical direction, each groove is in clearance fit with the upper limiting block (235), and the upper limiting block (235) is inserted into the grooves with different heights to adjust the included angle (alpha) between the baffle plate (232) and the horizontal plane.

5. An apparatus for removing non-metallic inclusions from superalloy powder as in claim 1, wherein the angle (α) between the baffle (232) and the horizontal plane is in the range of 30 ° to 60 °.

6. An apparatus for removing non-metallic inclusions from a superalloy powder as claimed in claim 1, wherein the electrostatic separation mechanism (23) is provided in two or more groups for gradually removing non-metallic inclusions from the superalloy powder.

7. An apparatus for removing non-metallic inclusions from a superalloy powder as in claim 1, wherein the baffle (232) is a non-magnetic stainless steel plate with a surface finish of Ra0.6.

8. The apparatus of claim 2, further comprising a control system, wherein the control system comprises a PLC, a human-machine interface connected to the PLC, a vacuum system control switch, an inert gas system control switch, a corona electrode array control switch, a spindle controller, and a brush controller;

the human-computer interface is used for setting relevant parameters in the control system.

9. A method for removing non-metallic inclusions in high-temperature alloy powder is characterized by comprising the following steps based on the device of any one of claims 1 to 8:

step one, after the powder feeding unit is connected with the powder discharging port of the electrostatic separation chamber, the vacuum system and the inert gas system are opened, and the electrostatic separation chamber is vacuumized to be less than 5 multiplied by 10^-3Pa, filling argon gas to 1.1-1.5 bar, and closing;

secondly, the baffle rotates to the upper limiting block, the corona electrode array is started to be high in voltage of 20-50 kV, and the angle of the baffle is adjusted to be 30-60 degrees;

step three, starting a powder feeding unit, feeding powder in batches, feeding powder for 10-20 min each time, finishing discharging metal powder after contacting with a baffle, overcoming rolling friction force generated by suction force of the baffle under the action of gravity to roll downwards in an accelerated manner, finally falling onto the next group of baffles, and removing non-metal impurities or directly falling into a qualified powder collecting tank again;

step four, closing the powder feeding unit and the corona electrode array voltage, starting a rotating motor and a moving motor after a rotating shaft drives a baffle to rotate to a lower limiting block, enabling a brush to move along a guide rail above the baffle at a moving speed of 10-20 mm/s and a rotating speed of 20r/min, and brushing the non-metal impurities adsorbed on the baffle down to a waste powder collecting tank;

and step five, repeating the step two, the step three and the step four until all the high-temperature alloy powder is subjected to electrostatic separation.

Technical Field

The invention belongs to the technical field of metal powder preparation, and particularly relates to a device and a method for removing non-metal impurities in high-temperature alloy powder.

Background

The nickel-based high-temperature alloy is mainly used for manufacturing hot end parts of engines such as turbine discs and the like, the thrust-weight ratio, the gas temperature before a turbine and the pressure increasing ratio of a gas compressor are continuously improved along with the improvement of the performance of the engines, the single-stage load is continuously increased, the stress level of parts is higher and higher, and the nickel-based high-temperature alloy has more rigorous requirements on the high-temperature strength, the fatigue performance, the durability and the like of materials. In the nickel-based high-temperature alloy, the gamma 'phase is directly related to the use temperature and the performance of the high-temperature alloy, the high-temperature strength of the alloy can be improved by increasing the content of the gamma' phase, the content of the gamma 'phase is gradually increased along with the continuous increase of the temperature of the fuel gas in front of a turbine disc, but the segregation of the alloy is aggravated by the increase of the gamma' phase, and the service life of a large-size ingot is seriously shortened.

The development of a powder metallurgy process, particularly the aging hot isostatic pressing technology, provides a new idea for the production of a large-size turbine disc, the component segregation of alloy powder prepared by two-phase flow atomization or centrifugal atomization can be controlled in a micron order, and then the densification is performed by using the hot isostatic pressing technology, so that the problem of the component segregation of the large-size turbine disc is effectively solved, and meanwhile, due to the non-directional stress in the hot isostatic pressing production process, the formed part has no difference in various properties, high-direction, radial and circumferential properties, so that the hot isostatic pressing technology becomes the only technology for preparing high-quality parts, particularly high-quality parts for aeroengines.

Although powder metallurgy high temperature alloys have incomparable performance advantages, since the birth of the powder metallurgy high temperature alloys, the original grain boundary, the heat induced hole and the non-metal inclusion defect in the alloys become important reasons for hindering the further development of the powder metallurgy high temperature alloys. The existing powder superalloy produced is very compact, the content of pores is very low, the original particle boundaries and heat-induced cavities are effectively solved, although many technical means are adopted, non-metallic inclusions in the powder superalloy cannot be completely avoided, so that the powder superalloy is a brittle material sensitive to gaps, and the performance of the powder superalloy is easily influenced by the inclusions.

The inclusions in the powder superalloy mainly come from two aspects, namely, the powder superalloy preparation process, such as alloy smelting and milling process, because some non-metallic inclusions (mainly SiO) are inevitably mixed in an induction melting crucible, a pouring gate, a milling nozzle, tool residues for cleaning and the like₂、Al₂O₃) On the other hand, the introduction of the powder is due to impure master alloy raw materials, poor deoxidation or improper powder handling. Meanwhile, the non-metal inclusions exist in the powder mainly in a granular form, but most of the non-metal inclusions are adhered with the powder granules to form abnormal non-metal inclusions due to the melting and resolidifying processes in the powder preparation process. The particulate nonmetallic inclusions can be reduced by 80-90% through conventional electrostatic separation, but the removal efficiency of abnormal nonmetallic inclusions adhered to metal powder is only 40-50% through a conventional method. The existence of the inclusions reduces the mechanical property of the powder superalloy, and particularly has more remarkable influence on the fatigue property and the crack propagation resistance of the material.

At present, the most effective method for removing abnormal nonmetallic inclusions in powder superalloy powder is an electrostatic separation method, and the stress condition of powder particles in the conventional electrostatic separation process is shown in figure 1. The roller rotates at a certain angular speed, and when powder particles flow through the surface of the roller, the powder particles are influenced by the centrifugal force of the roller, coulomb force given by a high-voltage electric field, adsorption force on the surface of the roller, gravity and rolling friction force. The metal particles are discharged quickly, so that the discharge is completed when the metal particles contact the surface of the roller, and when the roller rotates to a certain angle, the metal particles fly out when the centrifugal force is greater than the resultant force of gravity and the mirror surface adsorption force of the roller, and fall into qualified powder. Because the discharge of the non-metal inclusion is slow, a large amount of residual charges still exist after the non-metal inclusion contacts the roller, and when the non-metal inclusion rotates along with the roller, the resultant force of coulomb force, gravity and roller mirror surface adsorption force given by an electric field is larger than centrifugal force. So that the nonmetal impurities cling to the surface of the roller and are brushed by the brush to fall into a waste powder area. However, the actual electrostatic separation process has the following two disadvantages:

firstly, when the non-metallic roller that flows through of graininess mix with, thereby can directly throw away the roller and get into good powder district because the centrifugal force of instantaneous application is great, the roller surface of flowing through is being mixed with in the unusual non-metal of adhesion metal powder, when the roller is contacted to the metal powder face, because metal powder accomplishes discharging, and the non-metal of the super adhesion of proportion of metal powder far is mixed with to can throw away by centrifugal force and get into qualified powder.

Secondly, when the non-metal inclusion surface contacts the roller, although the non-metal inclusion is acted by coulomb force because of slow discharge, because the proportion of the metal powder is larger, the rotating speed of the roller is faster, when the roller rotates to a certain angle, the centrifugal force throws away the electrostatic separation effect of the abnormal non-metal inclusion adhered with the metal powder, which can separate the non-metal inclusion from the roller and enter the powder-well area. Therefore, how to remove the abnormal nonmetallic inclusion in the powder superalloy powder more effectively is the key to the breakthrough development of powder metallurgy.

In view of the above, the present inventors have made experience and practice in related industries for many years, and have proposed a device and a method for removing non-metallic inclusions in superalloy powder, so as to overcome the drawbacks of the prior art.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a device and a method for removing non-metallic inclusions in high-temperature alloy powder.

The purpose of the invention is solved by the following technical scheme:

a device for removing non-metal impurities in high-temperature alloy powder comprises an electrostatic separation chamber, wherein a powder feeding unit is connected to a powder outlet at the top of the electrostatic separation chamber, an air suction port and an air inflation port are respectively formed in the upper end of the electrostatic separation chamber, the air suction port is connected with a vacuum system, the air inflation port is connected with an inert gas system, an electrostatic separation mechanism is arranged inside the electrostatic separation chamber, a waste powder collection tank and a qualified powder collection tank are arranged below the electrostatic separation chamber, the electrostatic separation mechanism is used for separating powder containing non-metal impurities and storing the separated non-metal impurities in the waste powder collection tank, and the separated metal powder is stored in the qualified powder collection tank;

the electrostatic separation mechanism comprises a corona electrode array, a baffle and a brush, wherein the baffle is positioned below the corona electrode array, one end of the baffle is fixedly connected with the rotating shaft, and the other end of the baffle is positioned at the upper position and the lower position of a horizontal plane where the axis of the rotating shaft is positioned and is respectively provided with an upper limiting block and a lower limiting block; send whitewashed unit and corona electrode array to open when the baffle rotates supreme stopper, rotate at the baffle and close when the stopper is down closed, when the baffle rotates supreme stopper, the lowest of baffle is located the top of qualified powder collecting tank or the top of a set of baffle down, and when the baffle rotated to the stopper down, the lowest of baffle was located the top of useless powder collecting tank to through the brush with absorbent nonmetal inclusion brush on the baffle fall to useless powder collecting tank.

The electrostatic separation mechanism further comprises a guide rail, the guide rail is arranged above the lower limiting block on the baffle in parallel, the hairbrush is movably arranged on the guide rail through a sliding block, and the sliding block is driven by a moving motor to enable the hairbrush to reciprocate on the guide rail;

the brush is arranged on a brush roller, and the brush roller is driven by a rotating motor to rotate along with the brush roller.

Furthermore, the corona electrode array mainly comprises 4-5 high-voltage electrodes which are arranged in parallel.

Further, the baffle is kept away from the one end of pivot, is provided with a plurality of recesses along vertical direction interval, every the recess all with last spacing piece clearance fit, insert the recess of different heights through last spacing piece for the size of adjustment baffle and horizontal plane contained angle alpha.

Further, the included angle alpha between the baffle and the horizontal plane ranges from 30 degrees to 60 degrees.

Further, the electrostatic separation mechanism is arranged into two or more groups and is used for gradually removing the non-metal impurities in the high-temperature alloy powder.

Furthermore, the baffle is a non-magnetic stainless steel plate, and the surface smoothness is Ra0.6.

Furthermore, the device also comprises a control system, wherein the control system comprises a PLC, a human-computer interface connected with the PLC, a vacuum system control switch, an inert gas system control switch, a corona electrode array control switch, a rotating shaft controller and a brush controller;

the human-computer interface is used for setting relevant parameters in the control system.

The method for removing the non-metal inclusions in the high-temperature alloy powder is based on the device and specifically comprises the following steps:

step one, after the powder feeding unit is connected with the powder discharging port of the electrostatic separation chamber, the vacuum system and the inert gas system are opened, and the electrostatic separation chamber is vacuumized to be less than 5 multiplied by 10^-3Pa, filling argon gas to 1.1-1.5 bar, and closing;

secondly, the baffle rotates to the upper limiting block, the corona electrode array is started to be high in voltage of 20-50 kV, and the angle of the baffle is adjusted to be 30-60 degrees;

step three, starting a powder feeding unit, feeding powder in batches, feeding powder for 10-20 min each time, finishing discharging metal powder after contacting with a baffle, overcoming rolling friction force generated by suction force of the baffle under the action of gravity to roll downwards in an accelerated manner, finally falling onto the next group of baffles, and removing non-metal impurities or directly falling into a qualified powder collecting tank again;

step four, closing the powder feeding unit and the corona electrode array voltage, starting a rotating motor and a moving motor after a rotating shaft drives a baffle to rotate to a lower limiting block, enabling a brush to move along a guide rail above the baffle at a moving speed of 10-20 mm/s and a rotating speed of 20r/min, and brushing the non-metal impurities adsorbed on the baffle down to a waste powder collecting tank;

and step five, repeating the step two, the step three and the step four until all the high-temperature alloy powder is subjected to electrostatic separation.

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

1. the invention relates to a device and a method for removing non-metallic impurities in high-temperature alloy powder, which are different from the prior electrostatic separation technology, and adopt non-roller rotation, the metal powder particles are not dragged by centrifugal force, the powder moves more fully in an electric field under the clamping of a parallel corona electrode array, so that the powder particles carry charges, and the non-metallic impurities are removed on an inclined baffle plate by utilizing the electrical property difference between metal and non-metal; on the other hand, no roller rotates, and even if a certain electrode discharges, the electrostatic separation of other powder is not influenced, and the effect of removing non-metallic inclusions due to the fact that the roller stops rotating due to discharging is not influenced. The method can improve the efficiency of removing the granular non-metallic inclusions in the electrostatic separation process, effectively reduce the content of abnormal non-metallic inclusions adhered to metal particles, prepare high-quality (purity) high-temperature alloy powder, and is favorable for improving the fatigue and crack expansion resistance of subsequent hot isostatic pressing molded parts and reducing the notch sensitivity of the alloy.

2. The invention relates to a device and a method for removing nonmetallic inclusions in high-temperature alloy powder.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention.

In order to more clearly illustrate the embodiments or technical solutions in the prior art of the present invention, the drawings used in the description of the embodiments or prior art will be briefly described below, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.

FIG. 1 is a graph of a force analysis of powder particles during prior art electrostatic separation;

FIG. 2 is a schematic structural view of an apparatus for removing non-metallic inclusions from superalloy powder according to the present invention;

FIG. 3 is a graphical representation of non-metallic inclusions adhered to metal particles to be removed in accordance with the present invention;

FIG. 4 is a graph of the force analysis of the powder particles during the electrostatic separation process of the present invention;

FIG. 5 is a flow chart of the method for removing non-metallic inclusions in superalloy powder according to the present invention;

FIG. 6 is a graph showing the morphology of the untreated powder of example 1 of the present invention;

FIG. 7 is a powder morphology distribution diagram in a waste powder collection tank after electrostatic separation in example 1 of the present invention;

FIG. 8 is a powder morphology distribution diagram in a qualified powder collection tank after electrostatic separation in example 1 of the present invention.

Wherein: 1 is a powder feeding unit; 2 is an electrostatic separation chamber; 21 is an air extraction opening; 22 is an inflation inlet; 23 is an electrostatic separation mechanism; 24 is a waste powder collecting tank; 25 is a qualified powder collecting tank; 231 is a corona electrode array; 232 is a baffle plate; 233 is a brush; 234 is a rotating shaft; 235 is an upper limit block; 236 is a lower limit block; 237 is a guide rail; alpha is the included angle between the baffle plate and the horizontal plane when the baffle plate rotates to the upper limit block.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatus consistent with certain aspects of the invention, as detailed in the appended claims.

In order to make those skilled in the art better understand the technical solution of the present invention, the following detailed description of the present invention is provided with reference to the accompanying drawings and examples.

Referring to fig. 2 to 4, the invention provides a device for removing non-metal impurities from high-temperature alloy powder, which comprises an electrostatic separation chamber 2, wherein a powder feeding unit 1 is connected to a powder outlet at the top of the electrostatic separation chamber 2, the powder feeding unit 1 is composed of a powder feeding pipe and a powder storage device, an air suction port 21 and an air charging port 22 are respectively formed in the upper end of the electrostatic separation chamber 2, the air suction port 21 is connected with a vacuum system, and the air charging port 22 is connected with an inert gas system and used for providing a vacuum and inert gas environment for a cavity of the electrostatic separation chamber 2, so that secondary pollution of powder particles is avoided.

The electrostatic separation chamber 2 is internally provided with an electrostatic separation mechanism 23, a waste powder collecting tank 24 and a qualified powder collecting tank 25 are arranged below the electrostatic separation chamber 2, the electrostatic separation mechanism 23 is used for separating powder containing non-metal impurities and storing the separated non-metal impurities in the waste powder collecting tank 24, and the separated metal powder is stored in the qualified powder collecting tank 25.

Specifically, the electrostatic separation mechanism 23 includes a corona electrode array 231, a baffle 232, and a brush 233; the baffle 232 is positioned below the corona electrode array 231, one end of the baffle 232 is fixedly connected with the rotating shaft 234, the rotating shaft 234 is installed on a gear and controls the rotating angle through a stepping motor, and the other end of the baffle 232 is positioned at the upper and lower positions of the horizontal plane where the axis of the rotating shaft 234 is positioned and is respectively provided with an upper limiting block 235 and a lower limiting block 236; send whitewashed unit 1 and corona electrode array 231 to open when baffle 232 rotates supreme stopper 235, rotate at baffle 232 and close when stopper 236 down, when baffle 232 rotates supreme stopper 235, the lowest of baffle 232 is located the top of qualified powder collection tank 25 or the top of a set of baffle down, when baffle 232 rotates stopper 236 down, the lowest of baffle 232 is located the top of useless powder collection tank 24 to through brush 233 with the adsorbed nonmetal inclusion brush fall to useless powder collection tank 24 on baffle 232.

The baffle 232 in the invention should be made of non-magnetic material and the surface should be smooth, preferably non-magnetic stainless steel plate, and the surface finish is Ra0.6 to prevent qualified metal powder from being adsorbed on the surface.

The electrostatic separation mechanism 23 further comprises a guide rail 237, the guide rail 237 is arranged above the lower limit block 236 of the baffle 232 in parallel, the hairbrush 233 is movably arranged on the guide rail 237 through a sliding block, and the sliding block is driven by a moving motor to enable the hairbrush 233 to reciprocate on the guide rail 237; the fur brush 233 is provided on a fur brush roller, and the fur brush roller is driven by a rotating motor to rotate the fur brush 233 along with the fur brush roller. That is, when the baffle 232 stays at the lower limit block 236, the brush 233 moves down and rotates along the upper surface of the baffle 232 to gradually remove the non-metallic impurities adsorbed on the upper surface of the baffle to the waste powder collecting tank 24, the guide rail 237 in the present invention is a telescopic structure (prior art, not described), that is, when the baffle 232 rotates around the rotating shaft 234, as shown in the attached drawings, the guide rail 237 is retracted and is located at the right side position with the brush 233 to prevent interference with the baffle. In addition, other structures can be adopted as long as the brush 233 can remove the non-metal particles adsorbed on the surface of the baffle 232 and the rotation of the baffle 232 is not hindered.

Preferably, the corona electrode array 231 of the invention mainly comprises 4-5 high voltage electrodes arranged in parallel.

According to the invention, one end of the baffle 232, which is far away from the rotating shaft 234, is provided with a plurality of grooves at intervals in the vertical direction, each groove is in clearance fit with the upper limiting block 235, the upper limiting block 235 is inserted into the grooves with different heights for adjusting the size of an included angle alpha between the baffle 232 and the horizontal plane, preferably, the included angle alpha between the baffle 232 and the horizontal plane is generally set to be 30-60 degrees, so that the formed inclination can ensure that the metal powder can smoothly roll into the qualified powder collecting tank 25 and simultaneously ensure that the non-metal impurities are adsorbed on the surface of the baffle 232.

Specifically, when the device of the present invention is used, the stress condition of the non-metal inclusions is as shown in fig. 4, when the powder particles flow through the baffle 232, under the action of the electric field coulomb force, the baffle adsorption force and the gravity, the metal powder completes discharge after contacting the baffle 232, overcomes the rolling friction force generated by the baffle adsorption force under the action of the gravity to move downwards in an accelerated manner, and finally falls onto the next group of baffles under the action of the gravity to remove the non-metal inclusions again or directly falls into the qualified powder collection tank 25; the nonmetal impurities are discharged slowly, the friction force generated is far larger than the gravity component and is captured by the baffle 232 under the action of the coulomb force of the electric field and the adsorption force of the baffle, and then the nonmetal impurities are brushed into the waste powder collecting tank 24 (waste powder area) under the action of the brush 233, particularly, when the abnormal nonmetal impurities (shown in fig. 3) generated by the adhesion of the metal powder fall, the nonmetal impurities adhered to the surface of the metal continuously receive the coulomb force under the continuous action of the electric field array, so that the friction with the baffle 232 is increased, the powder particles continuously perform deceleration movement, finally stay on the baffle 232 and are brushed by the brush 233 to the waste powder area, and the abnormal nonmetal impurities adhered to the metal powder are effectively removed.

In order to remove the non-metal impurities in the powder as much as possible and improve the purity of the powder, the device provides two means, one means is to repeatedly remove the metal powder with non-metal impurities by the device, namely to remove the powder stored in the qualified powder collecting tank 25 again; alternatively, as shown in fig. 2 of this embodiment, the electrostatic separating mechanism 23 is provided in two or more groups for gradually removing the non-metallic inclusions from the superalloy powder.

The device also comprises a control system, wherein the control system comprises a PLC, a human-computer interface connected with the PLC, a vacuum system control switch, an inert gas system control switch, a corona electrode array control switch, a rotating shaft controller and a brush controller; the human-computer interface is used for setting relevant parameters in the control system and automatically operates through the PLC, and control accuracy and working efficiency are improved.

As shown in fig. 5, the present invention is based on the above-mentioned apparatus (using two sets of electrostatic separation mechanisms 23), and further provides a method for removing non-metallic inclusions from high-temperature alloy powder, and in order to verify the effect of the method for removing non-metallic inclusions, the following specific embodiments are described as follows:

example 1:

step one, after the powder feeding unit 1 is connected with the powder discharging port of the electrostatic separation chamber 2, 5 kg (each kg contains 48 nonmetal impurities) of the powder before electrostatic separation shown in figure 6 is placed in the powder feeding unit 1, the electrostatic separation chamber 2 is sealed, and the powder feeding unit 1 is startedThe vacuum system vacuumizes the electrostatic separation chamber 2 from the pumping hole 21, and the vacuum degree in the electrostatic separation chamber 2 is less than 5 multiplied by 10^-3Pa closes the vacuum system, then starts the inert gas system to inject inert protective gas (argon or helium, preferably argon) into the electrostatic separation chamber 2 from the gas filling port 22, and closes the inert gas system when the pressure in the electrostatic separation chamber 2 reaches 1.1 bar.

And step two, the rotating shaft 234 is driven by the stepping motor to rotate clockwise, so that the baffle 232 is driven to rotate to the upper limit block 235, then the corona electrode array 231 is started to be high-voltage to 20kV, and the included angle alpha between the baffle 232 and the horizontal plane is adjusted to be 30 degrees.

And step three, opening the powder feeding unit 1, feeding powder in batches for 20min each time, finishing discharging metal powder after contacting the baffle 232, overcoming the rolling friction force generated by the suction force of the baffle under the action of gravity to roll downwards in an accelerated manner, and finally falling onto the next group of baffles to remove non-metal impurities again or directly falling into the qualified powder collecting tank 25.

And step four, closing the voltage of the powder feeding unit 1 and the voltage of the corona electrode array 231, reversely driving by the stepping motor, enabling the rotating shaft 234 to rotate anticlockwise so as to drive the baffle 232 to rotate to the lower limiting block 236, and then starting the rotating motor and the moving motor, enabling the brush to move along the guide rail 237 above the baffle at the moving speed of 10mm/s and the rotating speed of 20r/min, and brushing the non-metal impurities adsorbed on the baffle 232 down to the waste powder collecting tank 24.

And step five, repeating the step two, the step three and the step four until all the high-temperature alloy powder is subjected to electrostatic separation.

After the above steps are completed, the waste powder collecting tank 24 and the qualified powder collecting tank 25 are observed and confirmed, and the results show that as shown in fig. 7 and fig. 8, respectively, it can be seen from fig. 7 that the powder of the waste powder collecting tank after electrostatic separation contains a large amount of non-metallic impurities, and from fig. 8 that almost most of the qualified powder collecting tank after electrostatic separation is metal powder, and only 15 non-metallic impurities are present, that is, the non-metallic impurity removal rate reaches 93.75%, and this is only based on the effect of one-time removal of the above device.

Example 2:

firstly, connecting a powder feeding unit 1 with a powder feeding port of an electrostatic separation chamber 2, then placing 5 kg (each kg contains 50 non-metal impurities) of powder into the powder feeding unit 1, sealing the electrostatic separation chamber 2, starting a vacuum system to vacuumize the electrostatic separation chamber 2 from an air suction port 21, wherein the vacuum degree in the electrostatic separation chamber 2 is less than 5 multiplied by 10^-3Pa closes the vacuum system, then starts the inert gas system to fill argon gas into the electrostatic separation chamber 2 from the gas filling port 22, and closes the inert gas system when the pressure in the electrostatic separation chamber 2 reaches 1.3 bar.

And step two, the rotating shaft 234 is driven by the stepping motor to rotate clockwise, so that the baffle 232 is driven to rotate to the upper limit block 235, then the corona electrode array 231 is started to be high-voltage to 35kV, and the included angle alpha between the baffle 232 and the horizontal plane is adjusted to be 45 degrees.

And step three, opening the powder feeding unit 1, feeding powder in batches for 15min each time, finishing discharging metal powder after contacting the baffle 232, overcoming the rolling friction force generated by the suction force of the baffle under the action of gravity to roll downwards at an accelerated speed, and finally falling onto the next group of baffles to remove non-metal impurities again or directly falling into the qualified powder collecting tank 25.

And step four, closing the voltage of the powder feeding unit 1 and the voltage of the corona electrode array 231, reversely driving by the stepping motor, enabling the rotating shaft 234 to rotate anticlockwise so as to drive the baffle 232 to rotate to the lower limiting block 236, and then starting the rotating motor and the moving motor, enabling the brush to move along the guide rail 237 above the baffle at the moving speed of 15mm/s and the rotating speed of 20r/min, and brushing the non-metal impurities adsorbed on the baffle 232 down to the waste powder collecting tank 24.

And step five, repeating the step two, the step three and the step four until all the high-temperature alloy powder is subjected to electrostatic separation.

After the treatment of the steps is completed, only 11 non-metallic impurities exist in the qualified powder collecting tank through observation and statistics, namely the non-metallic impurity removal rate reaches 95.6%.

Example 3:

firstly, connecting a powder feeding unit 1 with a powder feeding port of an electrostatic separation chamber 2, then placing 5 kg (each kg contains 47 non-metal impurities) of powder into the powder feeding unit 1, sealing the electrostatic separation chamber 2, starting a vacuum system to vacuumize the electrostatic separation chamber 2 from an air suction port 21, wherein the vacuum degree in the electrostatic separation chamber 2 is less than 5 multiplied by 10^-3Pa, the vacuum system is closed, then the inert gas system is started to charge argon gas into the electrostatic separation chamber 2 from the gas charging port 22, and the inert gas system is closed when the pressure in the electrostatic separation chamber 2 reaches 1.5 bar.

And step two, the rotating shaft 234 is driven by the stepping motor to rotate clockwise, so that the baffle 232 is driven to rotate to the upper limit block 235, then the corona electrode array 231 is started to be high-voltage to 50kV, and the included angle alpha between the baffle 232 and the horizontal plane is adjusted to be 60 degrees.

And step three, opening the powder feeding unit 1, feeding powder in batches for 10min each time, finishing discharging metal powder after contacting the baffle 232, overcoming the rolling friction force generated by the suction force of the baffle under the action of gravity to roll downwards at an accelerated speed, and finally falling onto the next group of baffles to remove non-metal impurities again or directly falling into the qualified powder collecting tank 25.

And step four, closing the voltage of the powder feeding unit 1 and the voltage of the corona electrode array 231, reversely driving by the stepping motor, enabling the rotating shaft 234 to rotate anticlockwise so as to drive the baffle 232 to rotate to the lower limiting block 236, and then starting the rotating motor and the moving motor, enabling the brush to move along the guide rail 237 above the baffle at the moving speed of 20mm/s and the rotating speed of 20r/min, and brushing the non-metal impurities adsorbed on the baffle 232 down to the waste powder collecting tank 24.

And step five, repeating the step two, the step three and the step four until all the high-temperature alloy powder is subjected to electrostatic separation.

After the treatment of the steps is completed, only 10 non-metallic impurities exist in the qualified powder collecting tank through observation and statistics, namely the non-metallic impurity removal rate reaches 95.74%.

The specific embodiment shows that the invention not only can improve the efficiency of removing the granular non-metallic inclusions in the electrostatic separation process, but also can effectively reduce the content of abnormal non-metallic inclusions adhered to the metal particles; in addition, compared with the conventional electrostatic separation powder, the high-temperature alloy powder treated by the method is applied to prepare the turbine disc, and under the same heat treatment condition, the mechanical properties of the turbine disc prepared by the method are outstanding, particularly, the fatigue and crack expansion resistance of a workpiece are excellent, and the notch sensitivity of the alloy is reduced.

The foregoing are merely exemplary embodiments of the present invention, which enable those skilled in the art to understand or practice the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention.

It is to be understood that the present invention is not limited to what has been described above, and that various modifications and changes may be made without departing from the scope thereof. The scope of the invention is limited only by the appended claims.