WO2010000209A1

WO2010000209A1 - Method and apparatus for production of semi-solidified alloy slurry by electromagnetic stirring in annulus of tank

Info

Publication number: WO2010000209A1
Application number: PCT/CN2009/072611
Authority: WO
Inventors: 徐骏; 张志峰; 白月龙; 石力开
Original assignee: 北京有色金属研究总院
Priority date: 2008-07-04
Filing date: 2009-07-03
Publication date: 2010-01-07

Abstract

An apparatus for production of semi-solidified alloy slurry by electromagnetic stirring in annulus of a tank, mainly includes an electromagnetic stirrer(1), a heat preserving system(2), an outer cooled body for controlling cooling of slurry(3), a production crucible for preparation of slurry(6), a standing crucible for holding molten alloy(11) and a crucible for melting(12). An inner cooled body for controlling cooling of slurry(14) is arranged in the central portion of the production crucible (6), thereby forming annulus between the outer wall of the inner cooled body(14) and the inner wall of the production crucible(6). A method for production of semi-solidified alloy slurry by electromagnetic stirring in annulus of a tank is characterized in that, pouring molten alloy with a temperature of 5~200℃ higher than liquidus temperature into the annulus between the outer wall of the inner cooled body(14) and the inner wall of the production crucible(6), and molten alloy is strongly agitated by the electromagnetic stirrer(1), at the same time the cooling medium passed into the outer cooled body(3) and the inner cooled body(14) ensures slurry(7) an more uniform temperature field, thus semi-solidified compositions with fine and even crystal grains are prepared.

Description

Device and method for preparing semi-solid alloy slurry by circumferential seam electromagnetic stirring

The invention belongs to the technical field of semi-solid metal processing and relates to a device and a method for preparing a semi-solid alloy rheological slurry or blank. In particular, an apparatus and method are provided for preparing a large gauge semi-solid alloy rheological slurry or blank.

Background technique

Since the invention of semi-solid metal forming technology by the American Institute of Technology's Flemings in the 1970s, semi-solid metal paste preparation and forming technology has attracted widespread attention from all over the world as a new type of technology. Investing a large amount of manpower, material resources and financial resources to carry out related research and development of this technology. At present, many methods for preparing metal paste have been invented. At present, the main reports are: electromagnetic stirring method; mechanical stirring method; double helix Stirring method, single spiral stirring method; low superheat casting and weak electromagnetic stirring method; bubble method, low superheat inclined plate casting method, melt mixing method and the like. Similarly, many semi-solid alloy forming technologies have been developed, the main ones are: traditional mechanical agitating flow forming technology; double helix mechanical agitating flow forming technology; near liquid-liquid casting type flow forming technology Low superheat inclined plate casting flow forming technology; low superheat casting and weak electromagnetic stirring flow forming technology; low superheat casting and weak mechanical stirring flow forming technology. In the semi-solid slurry pulping method and the stream forming method of the above invention, the electromagnetic stirring slurry preparation technology has the advantages of not polluting the alloy, the alloy slurry is pure, the control parameters are easy to adjust, and the rheological slurry can be continuously produced or continuously. The advantages of ingot casting, etc., have been put into commercial production and have obtained a wide range of applications. It has become the main preparation method for producing semi-solid metal and alloy pastes at present, but due to the existence of electromagnetic induction skin effect, the internal solution of the slurry The electromagnetic stirring force is obviously different. The surface of the slurry is subjected to a large stirring force and the inside is small, resulting in uneven distribution of the prepared semi-solid slurry, and the surface temperature of the slurry is low and the internal temperature is high. These factors lead to uneven distribution of the semi-solid slurry prepared, the surface layer is relatively small granular or rose-like, and the interior tends to be coarser rose crystals or dendrites, and the slurry or blank structure is poor. This has affected the further expansion of the scope of application of this technology or the improvement of competitiveness. Therefore, the semi-solid pulping industry generally regards the skin effect of electromagnetic induction as an unfavorable factor and tries to avoid it. In the pulping production, the method of reducing the electromagnetic stirring frequency and increasing the skin depth of the electromagnetic field is often used to overcome The adverse effect of the skin effect on the texture of the slurry attempts to obtain a more ideal semi-solid slurry structure. However, this will result in a large pulping equipment, high investment costs, and high slurry preparation costs.

In a method and apparatus for preparing semi-solid metal and alloy slurries or billets by electromagnetic stirring, U.S. Patent No. 4,344,837 and U.S. Patent No. 4,229,210 disclose various methods of preparing electromagnetic stirring of semi-solid metal and alloy slurries and billets. The principle is to break the primary dendrites by strong electromagnetic stirring, and inhibit the growth of primary crystal grains into dendritic crystals, thereby preparing semi-solid metal and alloy slurry of spherical or granular primary crystal grains. In the electromagnetic stirring method and apparatus disclosed in the above patent, the problem of cooling inside the slurry is not mentioned, and the internal cooling mechanism is not mentioned. However, when the semi-solid slurry is prepared by the electromagnetic stirring method disclosed in the above patent, the distribution of the temperature field of the slurry is not uniform, the outer layer of the slurry dissipates quickly, and the inner heat dissipation of the slurry is slow, resulting in the primary crystal grains in space and time. There is a significant difference in the upper generation, the primary crystal grains of the outer layer of the slurry are precipitated first, and the primary crystal grains inside the slurry are precipitated, which will eventually lead to unevenness of the slurry structure, for large size and large size slurry or The billet is even more so. Moreover, due to the skin effect of the electromagnetically induced magnetic field, the magnetic field strength decreases exponentially from the outer edge to the center of the slurry, resulting in a strong agitation of the outer layer of the slurry, and a weak agitation at the center of the slurry. Therefore, in the slurry or blank structure obtained by this method, the microstructure distribution is very uneven, the outer layer is fine, the inner layer is coarse, and the microstructure is different, and the primary crystal grains of the outer layer are spherical or granular, and the center It is dendritic or rose-like, so the size of the semi-solid slurry or blank prepared by the above method is also limited, and it is difficult to prepare high-quality large-size and large-sized semi-solid metal and alloy pastes or blanks. Solid metal or alloy bars, generally not exceeding 150 in diameter, so how to overcome the above shortcomings of electromagnetic stirring, to prepare uniform and fine semi-solid metal and alloy slurry or blank, especially to prepare large-size and large-size semi-solid Metal and alloy pastes or billets will be of great significance and practical value.

Chinese Patent 200420112702.0 also proposes a device and a method for continuously preparing a semi-solid metal slurry by a composite electromagnetic stirring method. The main structure and principle of the device are: electromagnetic stirring is applied in the tundish to uniformly cool the liquid of the tundish overheated. At the liquidus temperature, strong electromagnetic stirring is applied outside the draft tube, and the metal liquid flow can be sufficiently rapidly cooled, so that the number of nucleation is greatly increased, and the solidified structure is remarkably refined. The preparation of the semi-solid metal slurry by the above-mentioned equipment and method can solve the problem that in the prior art, the liquidity of the pouring metal liquid is close to the liquidus temperature due to the simple static insulation, and the liquidity of the metal liquid is too low. The technical problem of variation can also avoid the problem of uneven cooling and uneven solidification structure due to the large size of the crucible prepared in the prior art and the uneven stirring of the metal liquid. In this apparatus, a composite electromagnetic stirring technique is employed, and the internal cooling mechanism of the slurry is not mentioned. However, when the device is used to prepare a semi-solid metal slurry, a strong composite electromagnetic stirring technique is used to facilitate the flow of the semi-solid alloy slurry, but the unevenness of the slurry temperature field and the unevenness of the slurry structure. Still obvious, it can only produce semi-solid metal paste or blank with small size, can not produce large-size semi-solid alloy slurry or blank, and the electromagnetic stirring equipment of the equipment adopts frequency conversion device, and the purchase cost is high. The structure is complex, which also limits the promotion and application of the device.

In short, in the apparatus and method for preparing semi-solid metal and alloy slurry or blank by electromagnetic stirring method adopted at home and abroad, even if various measures such as low-frequency stirring are employed, due to the skin effect and the inherent heat dissipation characteristics of the slurry, The temperature field distribution and the distribution of the slurry still have large non-uniformity, and it is difficult to produce high-quality semi-solid slurry or blank, which limits the further development and application of the technology. Therefore, how to overcome these problems has become the current expansion. Electromagnetic stirring technology is the key to the application range of semi-solid metal paste.

Summary of the invention

In contrast to the foregoing patents and the electromagnetic stirring methods currently employed, in an attempt to avoid the skin effect, an object of the present invention is to provide a device and method for preparing a semi-solid metal rheological slurry or blank by annular seam electromagnetic stirring, the device and method The skin effect of electromagnetic stirring is fully utilized, and the semi-solid slurry obtained by the device and method has uniform microstructure, small size and good shape, and is favorable for producing qualified high-quality semi-solid metal or alloy blank or slurry.

In order to achieve the above object, the present invention adopts the following technical solutions:

An apparatus for preparing a semi-solid metal rheological slurry or billet, the apparatus comprising a preparation crucible, wherein an outer cooling controller, an insulation system, and a magnetic stirrer are disposed in order from the inside to the outside of the preparation crucible; The top of the crucible is provided with a stationary crucible which is connected to the preparation crucible through a heat insulating cover on the preparation crucible through a draft tube at the bottom thereof, and a melting crucible is disposed on the upper portion of the stationary crucible; and is provided at the bottom of the preparation crucible a draft tube, the draft tube for preparing the bottom of the crucible and the bottom tube of the melting crucible each having a valve; wherein: the middle portion of the preparation crucible is provided with an internal cooling controller, and The outer wall of the internal cooling controller forms an annular gap with the inner side wall of the preparation crucible.

The device for preparing a semi-solid metal rheological slurry or blank of the invention fully utilizes the skin effect of electromagnetic stirring, and the main principle thereof is: According to the principle of electromagnetic induction, the magnetic field strength decreases from the surface of the slurry to the inward exponential curve, the closer On the surface of the slurry, the greater the magnetic induction, the closer to the inside of the slurry, the smaller the magnetic induction, and the magnetic induction is small at the part larger than the skin depth, that is, in order to make the slurry to have a strong stirring force, the inside of the slurry The magnetic induction intensity of the region should be sufficiently large. For this purpose, all of the semi-solid alloy melt can be placed in a region from the surface of the slurry to the inner width not exceeding the skin depth, that is, the agitation region is a narrow slit. The slurry is formed by a "film" which can be appropriately adjusted in thickness, and the width of the slit is at most the skin depth. Of course, in order to achieve strong stirring strength, the width of the slit can be adjusted and narrowed, and the smaller the gap, penetrates into the interior of the slurry. The stronger the magnetic induction, the more vigorous the stirring, the more uniform the agitation, and then the semi-solid alloy slurry obtained by stirring. Rheological survive shaping, or made into billets touch performance.

According to the principle, the present invention provides an internal cooling controller that can be passed through a cooling medium in the preparation of the crucible, and the semi-solid alloy melt can be obtained by adjusting the annular gap formed between the outer wall of the internal cooling controller and the inner side wall of the preparation crucible. Strong agitation is carried out in the gap under the action of electromagnetic stirring force, and the cooling medium introduced in the internal cooling controller and the external cooling controller can make the heat dissipation of the slurry more uniform and the temperature field distribution is more uniform. Got The distribution of the resulting slurry is also more desirable.

By adopting the device of the invention, the shortcomings of the current electromagnetic stirring device adopting the frequency conversion system are large and complicated, and the investment cost is high, and the electromagnetic stirring can be performed in the production as long as the power frequency is used, without using the low frequency stirring, nor The need for a frequency conversion system is of great practical significance and practical value for reducing the investment cost of the enterprise and reducing the production cost of the semi-solid components, and expanding the application range of the semi-solid.

The draft tube of the apparatus for preparing a semi-solid rheological slurry or blank of the present invention can be connected to a die casting machine, an extruder, a continuous casting machine, a forging machine, and subjected to rheological die casting, rheological extrusion casting, rheological continuous casting, For rheological forging, the connection is as follows:

The structure of the draft tube connecting die casting machine of the apparatus for preparing a semi-solid rheological slurry or blank of the present invention is as follows: the draft tube for preparing the bottom of the crucible is connected to the injection chamber of the die casting machine, on one side of the shot chamber A punch is arranged inside, and the other side of the injection chamber is connected to a die-casting fixed mold and a die-casting movable mold.

The structure of the draft tube connecting extruder of the apparatus for preparing a semi-solid rheological slurry or blank of the present invention is as follows: the draft tube for preparing the bottom of the crucible is connected to the extrusion barrel of the extruder, and one of the extrusion tubes The extrusion rod is arranged in the side, and the other side of the extrusion barrel is connected to the extrusion mold right type and the extrusion mold left type.

The structure of the draft tube connecting continuous casting machine for preparing the semi-solid rheological slurry or blank of the present invention is as follows: the draft tube for preparing the bottom of the crucible is connected to the tundish of the continuous casting machine, and the tundish is connected to the crystallizer, A plurality of cooling water nozzles are uniformly distributed around the outlet of the crystallizer, and a lowering device outside the outlet of the crystallizer has a traction mechanism.

The structure of the draft tube connection forging machine of the apparatus for producing a semi-solid rheological slurry or blank of the present invention is as follows: The draft tube for preparing the bottom of the crucible is connected to the forged mold cavity in the forging mold.

In the apparatus for preparing a semi-solid metal rheological slurry or blank of the present invention, the internal cooling controller is a cooling passage through which a cooling medium is passed, and the cooling passage is composed of a central tube and an outer sleeve thereof, the central tube The upper port is the cooling medium input port, the lower port of the center pipe is in communication with the outer casing, and the center pipe constitutes a cooling medium input passage; the upper port of the outer casing is a cooling medium output port, and the outer casing constitutes a cooling medium output passage.

In the apparatus for preparing a semi-solid metal rheological slurry or blank of the present invention, the shape of the cooling medium input passage along the radial direction, that is, the cross section of the central tube is circular, elliptical, square or trapezoidal; The shape of the cooling medium input passage, that is, the center tube, in the axial direction is a straight tube shape or a curved tube shape.

In the apparatus for preparing a semi-solid metal rheological slurry or blank of the present invention, the appearance of the cooling medium output passage along the radial direction, that is, the outer cross section of the outer sleeve is circular, elliptical, square or The shape of the cooling medium output passage, that is, the outer sleeve along the axial direction, is a straight tube shape, a serpentine tube shape, a spiral tube shape, a wave tube shape or other curved tube shape; or the inner wall of the outer sleeve is along The shape in the axial direction is a straight pipe wall shape The shape of the outer wall in the axial direction is spiral or wavy. Considering that the outer sleeve is formed into a serpentine tube shape, a spiral tube shape, a wave tube shape or other curved tube shape, the situation is complicated and the manufacturing process is difficult; from the viewpoint of ease of manufacture, it is preferable to make the inner wall of the outer sleeve along the shaft. The shape in the direction of the direction is a straight pipe wall shape, and the outer wall thereof is formed in a spiral shape or a wave shape in the axial direction.

In the apparatus for preparing a semi-solid metal rheological slurry or blank of the present invention, the cooling medium input passage is made of austenitic stainless steel, titanium, molybdenum, cobalt, chromium, nickel, copper or the like. Non-metallic materials such as graphite, ceramics, corundum; The output channels of the cooling medium are austenitic stainless steel, non-magnetic metal materials such as titanium, molybdenum, cobalt, chromium, nickel, copper, or non-metallic materials such as graphite, ceramics, and corundum. It is stated here that the material of the cooling medium input channel and the cooling medium output channel must be non-magnetic metal or non-metal material, mainly to prevent it from affecting the electromagnetic field.

In the apparatus for producing a semi-solid metal rheological slurry or blank of the present invention, the inner passage of the cooling medium input passage, that is, the inner tube is 2 to 1000 mm, and the inner diameter of the cooling medium output passage, that is, the outer sleeve, is 5 to 1000 mm.

In the apparatus for producing a semi-solid metal rheological slurry or blank of the present invention, the cross-sectional shape of the crucible is round, elliptical or square; and the longitudinal cross-sectional shape of the crucible is square or broad and narrow.

In the apparatus for producing a semi-solid metal rheological slurry or blank of the present invention, an outer wall of the internal cooling controller, that is, an outer wall of the cooling medium output passage and an inner side wall of the preparation crucible, form an annular gap, and the cross-sectional shape of the annular slit It is circular, elliptical or square; the width of the annular slit shown by the longitudinal section of the annular slit is equal to the width of the upper part and the lower part, or the width of the upper width and the lower part having a gradient; the width of the annular gap is 0. 5~300mm In the apparatus for preparing a semi-solid metal rheological slurry or blank of the present invention, the outer wall of the cooling medium output passage has a spiral shape in the axial direction, and has a pitch of 5 to 100 mm and a high thread. It is 2~100mm.

In the apparatus for preparing a semi-solid metal rheological slurry or blank of the present invention, the outer wall of the cooling medium output passage has a wave shape along the axial direction, and has a wave pitch of 5 to 100 mm and a corrugation height of 2 ~100mm.

In the apparatus for producing a semi-solid metal rheological slurry or blank of the present invention, the cooling medium introduced into the cooling passage is air, nitrogen, argon, tap water or other cooling liquid, and the temperature of the cooling medium is room temperature.

001MP a When the cooling medium in the internal cooling controller is a liquid, the inlet pressure is 0. 001MP _a , the inlet pressure is 0. 001MP _a . -1 2MP _a;. in the case where the case where the cooling medium to the external cooling gas controller, which inlet pressure of 0. 001MPa-0 5MPa, cooled when the cooling medium of the external controller is liquid, imports The pressure is 0. 001MPa-l. 2MPao

A method for preparing a slurry or a blank of a semi-solid metal or alloy using the apparatus of the present invention, pouring a liquid metal or alloy liquid higher than a liquidus temperature of 5 to 200 ° C into a crucible inner wall and an internal cooling controller Between outer walls In the annular gap, and open the electromagnetic stirrer to stir the liquid metal or alloy liquid in the annular gap, prepare the semi-solid slurry, and simultaneously pass the room temperature to the external cooling controller and the internal cooling controller respectively. The cooling medium has a cooling rate of l~150 ° C / min, so that the prepared semi-solid slurry temperature field is more uniform, thereby obtaining a fine and uniform semi-solid slurry structure, and controlling the temperature of the semi-solid slurry below Its liquidus temperature is higher than its solidus temperature.

The temperature range of the semi-solid slurry is the temperature interval between the solidus and liquidus of the metal or alloy melt, that is, the temperature of the semi-solid slurry is lower than the liquidus temperature and higher than the solidus temperature. The determination of the temperature of the semi-solid slurry is determined according to the complexity of the formed part and the specific conditions during the operation. If the part is complicated, the temperature of the semi-solid slurry required is higher for filling. The parts are simple and the required semi-solid slurry can be cooler. Therefore, the temperature of the semi-solid slurry is determined according to the complexity of the part and the specific conditions during the operation. For different alloys of different parts, the temperature of the semi-solid slurry is different.

In the method of the present invention, the flow rate of the cooling medium introduced into the internal cooling controller and the external cooling controller is a flow rate of the cooling medium of 0 to 200 liters / min, and ≠0.

In the method of the present invention, the electromagnetic stirrer uses an induction alternating current rotating electromagnetic stirrer, and the frequency is 5 to 100 Hz.

In the method of the present invention, during the preparation of the semi-solid slurry, the temperature difference between the inside and the outside of the semi-solid slurry is controlled within ± 3 ° C, and the temperature difference between the inside and the outside of the semi-solid slurry is a semi-solid slurry on the outer wall of the internal cooling controller. The difference between the temperature of the feed and the temperature of the semi-solid slurry in the inner side wall of the crucible.

In the method of the present invention, the prepared semi-solid slurry is a semi-solid aluminum-based alloy slurry, a semi-solid magnesium-based alloy slurry, a semi-solid zinc-based alloy slurry, a semi-solid copper-based alloy slurry, and a semi-solid nickel. Any of a base alloy slurry, a semi-solid cobalt-based alloy slurry, and a semi-solid iron-based alloy slurry; or a semi-solid aluminum-based composite slurry, a semi-solid magnesium-based composite slurry, and a semi-solid zinc-based composite Any one of a material slurry, a semi-solid copper-based composite slurry, a semi-solid nickel-based composite slurry, a semi-solid cobalt-based composite slurry, and a semi-solid iron-based composite slurry.

In the method of the present invention, the semi-solid slurry is completely solidified in the preparation crucible to obtain a semi-solid aluminum alloy billet, a semi-solid magnesium alloy billet, a semi-solid zinc alloy billet, a semi-solid copper alloy billet, and a semi-solid nickel. a billet of any one of an alloy billet, a semi-solid cobalt alloy billet and a semi-solid iron-based alloy billet; or a billet of a semi-solid aluminum-based composite material, a blank of a semi-solid magnesium-based composite material, a blank of a semi-solid zinc-based composite material, a blank of a semi-solid copper-based composite material, a blank of a semi-solid nickel-based composite material, a blank of a semi-solid cobalt-based composite material, and a blank of a semi-solid iron-based composite material, the above-mentioned blank material can be used as a semi-solid thixotropic Formed raw blank.

In the method of the present invention, in the preparation of the semi-solid slurry, the inner side wall and the internal cooling control are prepared A protective gas is formed in the annular gap formed between the outer walls of the vessel to prevent or reduce oxidation of the metal or alloy, which is argon, nitrogen or helium.

In the method of the present invention, the materials for preparing the crucible, the internal cooling controller and the external cooling controller are all non-metallic or non-magnetic metals.

In order to overcome the adverse effects of the electromagnetic induction skin effect, the present invention provides an internal cooling controller that can be passed through the cooling medium in the preparation crucible, and an annular gap is formed between the outer wall of the internal cooling controller and the inner side wall of the preparation crucible. The solid alloy melt is strongly stirred in the gap under the action of electromagnetic stirring force, and the cooling medium introduced in the internal cooling controller can make the heat dissipation of the slurry more uniform and the temperature field distribution is more uniform. The slurry distribution is also more ideal.

For this purpose, a certain degree of superheated liquid metal and alloy can be poured into the annular space, and the metal and alloy melt are strongly stirred under the action of electromagnetic stirring force. At the same time, the temperature field of the slurry is more uniform under the co-cooling action of the internal cooling controller and the preparation crucible, so that the agitating force field and temperature field of the slurry will be more uniform, thereby obtaining a high quality semi-solid slurry, and then The semi-solid slurry is directly transferred to a die casting machine or a forging machine or an extruder to form; or the obtained semi-solid slurry is completely solidified into a billet, and then the billet is reheated to a semi-solid section, and then the billet is transferred to a die casting machine or Forging machine and extruder forming. The preparation process is simple, the operation is convenient, the semi-solid structure is excellent in morphology and the preparation cost is low, and is very suitable for preparation of semi-solid metal and alloy slurry or blank.

The specific preparation process of the present invention is as follows:

1. A metal and alloy melt having a certain degree of superheat. The temperature of the melt is controlled at a temperature of 5 to 200 ° C above the liquid phase temperature, and the melt is poured between the inner wall of the crucible and the outer wall of the internal cooling controller. Inside the annular gap.

2. The shape of the preparation crucible is cylindrical, the shape of the internal cooling controller is a hollow bottom sealed straight tubular shape, and the shape of the external cooling controller is a spiral tube. The preparation 坩埚, internal cooling controller and external cooling controller are made of non-metallic or non-magnetic metal. The annular gap formed between the inner wall of the preparation crucible and the outer wall of the inner cooling tube is 3 to 200 mm.

3. The electromagnetic stirrer uses an induction AC rotating electromagnetic stirrer with a frequency of 5~100Hz.

4. Preparation 外部 Externally set external cooling controller. The external cooling controller and internal cooling controller are supplied with cooling medium at room temperature, nitrogen, argon or room temperature cold water at a flow rate of 0~200 liters/min and ≠0.

5. After casting, the metal and alloy slurry are strongly stirred in the annular gap, and the slurry temperature is gradually lowered under the cooling effect of the internal cooling controller and the external cooling controller, and the flow rate of the cooling medium is adjusted to make the slurry The cooling rate is l~150 °C/min, and ≠0. The temperature field of the semi-solid metal or alloy slurry is made uniform, and the temperature difference between the inside and the outside of the semi-solid slurry is controlled to not exceed ± 3 °C. 6. During the preparation process, the shielding gas may be introduced to avoid or reduce the oxidation of metals and alloys. The shielding gas may be a shielding gas such as argon gas, nitrogen gas or helium gas.

7. After the slurry temperature reaches the predetermined temperature, the slurry is immediately transferred to a die casting machine or a forging machine, an extruder to form, or the slurry is completely solidified in the preparation crucible to obtain a special semi-solid metal and An alloy blank that can be used as a semi-solid thixoforming original blank.

The advantages of the present invention over the prior art are:

1. Make full use of the skin effect of electromagnetic induction. Compared to the conventional electromagnetic stirring method, the invention avoids the adverse effects of the electromagnetic induction skin effect, and the slurry is subjected to a more uniform stirring force and temperature field. The invention concentrates all the slurry in the narrow inner region of the gap for agitation, the slurry is more vigorously stirred, the strength is greater, the agitation of the slurry is more uniform, and the internal and external stirring of the slurry is overcome by the conventional electromagnetic stirring. Uneven, uneven organization and other issues. In addition, by setting the internal cooling controller and the external cooling controller, the temperature field of the semi-solid alloy melt is uniform, and the obtained semi-solid slurry is uniform, small, and well-formed, and the radial size of the internal cooling controller can be freely selected. In this way, the distance between the internal cooling controller and the inner wall of the preparation crucible (ie, the thickness of the slurry) can be freely adjusted, which is advantageous for obtaining a larger shear rate of the slurry and obtaining a fine and uniform structure.

2. It can produce large-size semi-solid alloy slurry or blank. The invention provides an internal and external cooling controller, which can not only obtain strong electromagnetic stirring of the slurry, but also obtain uniform stirring force inside the slurry, obtain uniform slurry structure, and balance the temperature field of the semi-solid alloy melt, and promote The alloy melt nucleates in a large amount, inhibits the formation or growth of dendrites, and finally forms a semi-solid structure. At the same time, the internal cooling controller will a certain agitating effect on the agitated alloy melt, which will promote the breaking and dissociation of the primary crystal grains. Through the above measures, a fine and uniform semi-solid structure can be obtained both inside and outside of the alloy melt, which is favorable for producing a qualified high-quality semi-solid alloy billet or slurry.

3. Semi-solid alloy slurry is pure. Since the electromagnetic stirrer is used as the stirring source, the stirring force generated by the stirring magnetic field acts on the alloy melt to avoid contamination of the alloy melt.

4. Prevent the semi-solid alloy melt from entraining gas. The alloy melt in the preparation of the crucible is in a relatively closed state, which prevents the entrainment of the semi-solid alloy melt, and the static standing argon provided can also effectively prevent the external gas from being caught in the alloy melt prepared in the crucible, and further provided The internal cooling controller can effectively prevent the movement of the electromagnetic stirring magnetic field from causing vortex in the alloy melt, and the surface of the alloy melt is gentle and prevents the gas from being blown.

5. The self-cleaning property of the melt is good. By setting the cooling medium output pipe of the internal cooling controller to a spiral shape, under the action of electromagnetic stirring force, the alloy melt is gradually collected to the bottom of the crucible, which can effectively avoid the alloy melt. In the internal cooling of the outer wall of the controller and the preparation of the inner wall of the crucible, reducing the amount of cleaning work, improving the utilization of the alloy and the life of the preparation of the internal cooling controller. 6. The equipment is simple and compact, with simple installation, simple process, convenient operation, low investment cost, strong practicability and wide application range. Compared with other semi-solid forming methods and conventional electromagnetic stirring methods currently used, the device is small in size, simple in equipment, and low in investment cost. The enterprise can perform electromagnetic stirring in the production process by using a power frequency without using low-frequency stirring. There is also no need for a frequency conversion system, which overcomes the shortcomings of the current electromagnetic stirring device using a variable frequency system, such as large structure and high complexity, and high investment cost, which can significantly reduce the preparation cost of semi-solid alloy slurry or blank, and ultimately reduce the production cost of semi-solid castings. Reinforce the competitiveness of semi-solid castings and expand the application range of semi-solid castings. The invention is suitable for the preparation of semi-solid pastes or blanks of aluminum-based alloys and composites thereof, and also for magnesium-based alloys, copper-based alloys, zinc. Preparation of semi-solid slurries or blanks of base alloys, iron-based alloys and other non-ferrous metal alloys and composites thereof. DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic view of a device for preparing a semi-solid metal rheological slurry or blank.

Fig. 2 is a schematic view showing the structure of an internal cooling controller in which the outer wall of the cooling medium output passage has a linear shape in the axial direction.

Fig. 3 is a schematic view showing the structure of an internal cooling controller in which the outer wall of the cooling medium output passage is wavy in the axial direction.

Fig. 4 is a schematic view showing the structure of an internal cooling controller in which the outer wall of the cooling medium output passage has a spiral shape in the axial direction.

Figure 5 is a schematic view of a device for preparing a semi-solid metal rheological slurry or blank equipped with a die casting machine.

Figure 6 is a schematic view of an apparatus for preparing a semi-solid metal rheological slurry or blank equipped with an extruder.

Figure 7 is a schematic view of a device for preparing a semi-solid metal rheological slurry or blank equipped with a continuous casting machine.

Figure 8 is a schematic view of a device for preparing a semi-solid metal rheological slurry or blank equipped with a forging machine.

Figure 9 is a quenched structure of the side of the semi-solid A357 aluminum alloy slurry prepared by the present invention, and the light-colored region is a spherical primary "-A/, and the dark region is a solidified eutectic liquid.

Figure 10 is a quenched structure of the middle portion of a semi-solid Α357 aluminum alloy slurry prepared by the present invention. The light-colored region is a spherical primary "-A/, and the dark region is a solidified eutectic liquid.

Figure 11 is a quenched structure of a semi-solid Α357 aluminum alloy slurry center prepared by the present invention, wherein the light-colored region is a spherical primary - Α/, and the dark region is a solidified eutectic liquid.

detailed description

1 is a schematic view of a device for preparing a semi-solid metal rheological slurry or blank. As shown in FIG. 1, the device includes a preparation crucible 6, and an external cooling controller 3 is disposed in the outer periphery of the preparation crucible 6 from the inside to the outside. , insulation system 2 a magnetic stirrer 1; a static raft 11 is disposed on the upper portion of the preparation crucible 6, and the stationary crucible 11 is passed through a heat-guiding cover 8 on the preparation crucible 6 through a guide tube 9 at the bottom thereof to communicate with the preparation crucible 6 The upper portion of the crucible 11 is provided with a melting crucible 12; and at the bottom of the preparation crucible 6, a draft tube 5 is provided, and the draft tube 5 for preparing the bottom of the crucible 6 and the draft tube 9 for the bottom portion of the crucible 12 are formed. Each has a valve 4, 10; the middle portion of the preparation crucible is provided with an internal cooling controller 14, the internal cooling controller 14 is a cooling passage through which a cooling medium is passed, and the cooling passage is composed of a central tube and an outer sleeve thereof. The upper port of the central pipe is a cooling medium input port, the lower port of the center pipe is connected to the outer casing, the central pipe constitutes a cooling medium input passage; the upper port of the outer casing is a cooling medium output port, and the internal cooling controller 14 can be cooled inside. medium. The external cooling controller 3 is a spiral tube having a plurality of uniformly distributed small holes which are placed inside the external thermal insulation system 2 for preparing the crucible 4 and at a certain distance from the outer wall of the preparation crucible, and the external cooling controller 3 is also inside. The cooling medium can be supplied. The crucible 6 is a cylindrical container which is placed inside the thermal insulation system to form a closed cavity. The internal cooling controller 14 is placed in the center of the preparation crucible 6. An annular gap is formed between the outer side wall of the inner cooling controller 14 and the inner side wall of the preparation crucible 6. The electromagnetic stirrer 1 is placed outside the thermal insulation system 2. And a thermocouple 13 is provided in the preparation crucible 6.

2 to 4, FIG. 2 to FIG. 4 are schematic diagrams showing the structure of the internal cooling controller 14. The internal cooling controller 14 is composed of a cooling passage and a cooling medium. The cooling passage is composed of a cooling medium input passage 14-1 and a cooling medium. The output channel 14-2 is composed. The cooling medium input channel 14-1 is a central tube with a hollow bottom opening, and the upper end of the central tube is a cooling medium input port, and the central tube can be circular, elliptical, square, or trapezoidal in the radial direction (cross section). Or other various shapes, the shape of the center tube in the axial direction is a straight tube shape or a curved tube shape, wherein the curved tube shape is a serpentine tube shape. The cooling medium output passage 14-2 is a hollow bottom sealed outer sleeve which is sleeved outside the center tube, and the center tube communicates with the outer sleeve through the bottom opening, and the upper opening of the outer sleeve is a cooling medium outlet. The bottom and the side wall of the outer sleeve may be integrally formed or sealed by welding and other methods, and the outer shape of the cooling medium output passage 14-2 in the radial direction (cross section), that is, the outer shape of the cross section of the outer sleeve may be a circle Shape, ellipse, square, trapezoid or other various shapes, the cooling medium output channel, that is, the shape of the outer sleeve along the axial direction is a straight tube shape, a serpentine tube shape, a spiral tube shape, a wave tube shape or other curved tube shape Or the inner wall of the outer sleeve is shaped like a straight tube wall in the axial direction and the outer wall has a spiral or wave shape along the axial direction. In FIG. 2, the shape of the outer sleeve along the axial direction is a straight tube shape; in FIG. 3, the inner wall of the outer sleeve has a straight tube wall shape along the axial direction and the outer wall along the axial direction. The shape of the outer sleeve is wavy; in Fig. 4, the inner wall of the outer sleeve has a straight tube wall shape in the axial direction and the outer wall has a spiral shape in the axial direction.

The material of the cooling medium input passage 14-1 may be a non-magnetic metal material such as steel, copper, titanium, tungsten, molybdenum aluminum or zinc or a non-metal material such as graphite or ceramic. The cooling medium output channel 14-2 can be made of non-metallic materials such as graphite or ceramic. Material. The cooling medium input channel 14-1 is placed in the cooling medium output channel 14-2 to form a cooling medium cooling channel, and the cooling medium input channel 14-1 and the cooling medium output channel 14-2 may be connected by bolting, welding or other methods. One. The cooling medium may be air, nitrogen, argon or the like, or the temperature of the cooling medium is room temperature. The inner diameter of the cooling medium input channel 14-1 is 2 200. The inner diameter of the cooling medium output channel 14-2 is 5 300. For the shape of the wave-shaped cooling medium output pipe, the pitch 1^ is 5 100!11 ₁ 11 ! ! for? ~^^!!!!!!, as shown in Figure 3; For a cooling medium output pipe with a spiral shape, the pitch L' is 5 100 and the thread height h' is 2 100 mm, as shown in Figure 4.

The main function of the external cooling controller 3 is to pass a cooling medium into the cooling pipe to cool the alloy melt to the required temperature. It is mainly composed of a cooling pipe and a cooling medium. The cooling pipe is a hollow cooling pipe, and the cooling pipe section The shape may be circular, elliptical, square, trapezoidal or other shape, and the shape of the cooling tube along the axial direction is a straight tube shape, a serpentine tube shape, a spiral tube shape, a wave tube shape or other curved tube shape; The shape of the inner wall of the cooling pipe in the axial direction is a straight pipe wall shape and the shape of the outer wall thereof in the axial direction is a spiral shape or a wave shape. The material of the cooling channel may be a metal-based material such as steel, copper, aluminum, zinc or magnesium or a non-metallic material such as ceramic. The cooling medium may be a gas such as air, nitrogen or argon, and the temperature of the cooling medium is room temperature. The external cooling controller 11 is placed inside the insulation system, around the preparation 坩埚 and at a distance from the preparation 10 (10 mm 300 mm).

As shown in Fig. 1, the main function of the valve 4 and the valve 10 is to control the flow of the alloy melt, the valve 4 controls the flow of the semi-solid alloy melt 7 to the flow tube 5, and the valve 10 controls the alloy melt in the stationary crucible 11. To the flow of the preparation crucible 6, the valve 4 and the valve 10 can be controlled manually or mechanically.

As shown in Fig. 1, the main function of the draft tube 5 and the draft tube 9 is to introduce an alloy melt or a semi-solid alloy slurry, and the upper portion of the draft tube 5 is connected to the preparation crucible 6; the upper portion of the draft tube 9 is static The lower portion is connected to the semi-solid alloy melt 7 in the preparation crucible 6, and the outside of the draft tubes 5 and 9 is wound around the heater to control the temperature of the draft tube.

The main function of preparing crucible 6 is to hold the alloy melt. The cross-sectional shape of the crucible can be round, square or elliptical. The material of the crucible can be graphite, copper or other non-magnetic metal or non-metal.

The main function of the electromagnetic stirrer 1 is to generate a strong electromagnetic force to agitate the alloy melt, so that the alloy melt is strongly stirred. The electromagnetic stirrer can be a rotating electromagnetic stirrer, a traveling wave electromagnetic stirrer, a composite electromagnetic stirrer and Other forms of electromagnetic stirrers.

FIG. 5 is a schematic diagram of a semi-solid metal and alloy slurry rheology die-casting equipment, which is obtained by directly placing or fixing a semi-solid rheological slurry preparation device as shown in FIG. 1 above a die casting machine. . The die casting machine is composed of a die-casting fixed mold 15, a die-casting movable mold 16, a shot chamber 17, and a punch 19. The draft tube 5 is placed above the shot chamber 17 for convenience The rheological slurry flows into the shot chamber 17.

Figure 6 is a schematic diagram of a semi-solid metal and alloy slurry rheological extrusion equipment, which is formed by directly placing or fixing a semi-solid rheological slurry preparation device as shown in Fig. 1 above the extruder. Equipment. The extruder consists of an extrusion die right type 20, an extrusion die left type 21, a squeeze barrel 22, and a squeeze bar 23. The draft tube 5 is placed above the extrusion barrel 22 to facilitate the flow of the rheological slurry into the extrusion barrel 22.

Figure 7 is a schematic diagram of a semi-solid metal and alloy slurry continuous casting equipment, which is a device in which a semi-solid rheological slurry preparation device as shown in Fig. 1 is directly placed or fixed on top of a continuous casting machine. . The continuous casting equipment consists of a tundish 24, a crystallizer 25, a cooling water nozzle 26 and a traction mechanism 27. The draft tube 5 is placed above the tundish 24 to facilitate the flow of the rheological slurry into the tundish 24,

FIG. 8 is a schematic diagram of a semi-solid metal and alloy slurry rheological forging equipment, which is obtained by directly placing or fixing a semi-solid rheological slurry preparation device as shown in FIG. 1 above a forging machine. . The forging equipment consists of a forging die 30 and a forging die cavity 29 therein, wherein a draft tube 5 is placed over the forging die cavity 29 to facilitate flow of the rheological slurry into the forging die cavity 29.

The main embodiment of the apparatus for preparing a semi-solid metal rheological slurry or blank of the present invention is:

Referring to Figures 1, 2, and 5, this is a process flow and apparatus provided in accordance with the above technical features. The superheated ZL101A aluminum alloy melt is melted by melting 坩埚12, and the enthalpy 12 is an electromagnetic induction heating furnace. The heat preservation performance is good, and the ZL101A alloy melt can ensure high temperature control precision, and the temperature control precision is ±10°C. The stationary crucible 11 is a crucible having excellent heat preservation performance, and the lower end opening is connected to the draft tube 9, and the bottom of the crucible 11 is opened and a valve 10 is provided to control the flow of the molten alloy in the stationary crucible to the preparation crucible 6. The static enthalpy 11 can provide a sufficient amount of alloy liquid for preparing 坩埚6, and the static enthalpy 11 can ensure that the temperature of the alloy melt is 5 to 200 V above the liquidus, and the temperature control precision is ±10. The upper part of the draft tube 9 is connected to the stationary crucible 11, and the lower opening is opened into the alloy melt in the preparation crucible 6. The outside of the draft tube 9 is wound with an electric resistance heater which heats the temperature of the draft tube to 400. °C, the preparation crucible 6 is placed inside the thermal insulation system 2, and the inner diameter of the crucible 6 is prepared to be 8O X 16Omm, and the crucible cover 8 having excellent heat insulation performance is prepared on the upper part of the crucible, and the cooling medium output pipe 14-2 of the internal cooling controller 14 is prepared. Using the structure shown in Figure 2, the outer diameter is 06Omm, the material is graphite, and the preheating temperature is 300 °C. The outer wall of the cooling medium output pipe 14-2 of the internal cooling controller 14 is spaced from the inner side wall of the preparation crucible 11 by a distance of 10 mm. The bottom of the internal cooling controller cooling medium output pipe 14-2 is 40 mm from the inner wall of the bottom of the preparation crucible. The cooling medium input pipe 14-1 of the internal cooling controller 14 has an outer diameter of 025, a pipe thickness of 3 mm, a material of stainless steel, and a temperature of room temperature. The thermal insulation system 2 is a nearly closed cylindrical structure that is hollow and has a top connected to the lid 8. It is surrounded by a good insulation material. This insulation system ensures the slow cooling of the alloy melt in the preparation of the crucible. The cooling rate is 1~150. °C/min, the external cooling controller 3 surrounds the outside of the preparation crucible 6 and is 20 mm away from the outer wall of the preparation crucible. A small ventilation hole is formed in the wall of the cooling duct of the external cooling controller 3, and the diameter of the small hole is 4 mm, and the external cooling controller is adjusted. The cooling medium flow rate of 3 can make the outer wall of the preparation crucible cool at a temperature of l~150 ° C / min, and the cooling medium is room temperature air. The die casting machine is composed of a die-casting type mold 15, a die-casting type mold 16, a shot chamber 17, and an injection punch 19. The draft tube 5 is connected to the lower port of the preparation crucible 6, and a valve 4 is arranged at the lower end of the crucible 6 to control the flow of the semi-solid alloy melt to the shot chamber. A certain amount of 670 ° C ZL101A alloy liquid is poured into the stationary crucible 11 , covered with a lid 8 , allowed to stand for 10 to 20 s, the valve 10 is opened, and the superheated ZL101A alloy liquid flows into the draft tube 9 to prepare the crucible. In the middle 6, when the amount of alloy melt to be inflow reaches about 2/3 of the volume of the prepared crucible 6, the valve 10 is closed, the electromagnetic stirrer 1 is turned on, the nominal power of the electromagnetic stirrer is set to 1300 W, and the internal and external cooling controllers are controlled. The flow rate of the cooling medium in 14, 3 is such that the cooling rate of the melt is 5 ° C / min, and the temperature indicated by the thermocouple 13 is 580 to 600 ° C, and the semi-solid ZL101A aluminum alloy slurry can be obtained. The electromagnetic stirrer 1 and the internal and external cooling controllers 14, 3 are closed, the valve 4 is opened, and the semi-solid ZL101A aluminum alloy slurry 7 flows into the injection chamber 17 through the draft tube 5, and the temperature of the draft tube 5 is controlled at 500°. C, the preheating temperature of the injection chamber 17 and the injection punch 19, the die-casting mold 15 and the die-casting mold 16 are 250 ° C, and the valve 4 is to be opened for about 5 seconds, and the semi-solid slurry 7 is completely discharged, and the valve is closed. 4. At the same time, the die casting machine punch 19 presses the semi-solid slurry 7 into the die-casting cavity. Press forming for about 4~8s, then take out the die casting, complete the rheological die casting of a semi-solid ZL101A aluminum alloy slurry, open the valve 10 at the same time of rheological die casting, and flow the superheated ZL101A alloy liquid into the preparation crucible 6, and enter the next time. Rheological die casting.

Referring to Figures 1, 2, and 6, this is a process flow and apparatus provided in accordance with the above technical features. The superheated ZL101A aluminum alloy melt is melted by melting 坩埚12, and the enthalpy 12 is an electromagnetic induction heating furnace. The heat preservation performance is good, and the ZL101A alloy melt can ensure high temperature control precision, and the temperature control precision is ±10°C. The stationary crucible 11 is a crucible having excellent heat preservation performance, and the lower end opening is connected to the draft tube 9, and the bottom of the crucible 11 is opened and a valve 10 is provided to control the flow of the molten alloy in the stationary crucible to the preparation crucible 6. The static enthalpy 11 can provide a sufficient amount of alloy liquid for preparing 坩埚6, and the static enthalpy 11 can ensure that the temperature of the alloy melt is 5 to 200 V above the liquidus, and the temperature control precision is ±10. The upper part of the draft tube 9 is connected to the stationary crucible 11, and the lower opening is opened into the alloy melt in the preparation crucible 6. The outside of the draft tube 9 is wound with an electric resistance heater which heats the temperature of the draft tube to 400. °C, the preparation crucible 6 is placed inside the thermal insulation system 2, and the inner diameter of the crucible 6 is prepared to be 8O X 16Omm, and the crucible cover 8 having excellent heat insulation performance is prepared. The cooling medium output pipe 14-2 of the internal cooling controller 14 has a structure as shown in Fig. 2, an outer diameter of 06Omm, a material of graphite, and a preheating temperature of 300 °C. The outer wall of the internal cooling controller cooling medium output pipe 14-2 is 10 mm away from the inner side wall of the preparation crucible. The bottom of the internal cooling controller cooling medium output pipe 14-2 is 40 mm from the inner wall of the preparation crucible bottom. Cooling medium input tube for internal cooling controller Lane 14-1 has an outer diameter of 025 and a pipe thickness of 3 mm. The material is stainless steel and the temperature is room temperature. The thermal insulation system 2 is a nearly closed cylindrical structure that is hollow and has a top connected to the lid 8. It is surrounded by a good thermal insulation material. This insulation system ensures that the alloy melt in the preparation crucible is slowly cooled at a cooling rate of l~150 °C/min. The external cooling controller 3 surrounds the outside of the preparation crucible 6 and is spaced apart. The outer wall of the crucible is prepared to be 20 mm, and a small air hole is formed in the cooling duct wall of the external cooling controller 3, and the diameter of the small hole is 4 mm. The cooling medium flow rate of the external cooling controller 3 can be adjusted to make the outer wall cooling speed of the preparation crucible l~150 °C/ Min, the cooling medium is room temperature air. The extruder consists of an extrusion die right type 20, an extrusion die left type 21, a squeeze barrel 22, and a squeeze bar 23. The draft tube 5 is connected to the lower port of the preparation crucible 6, and a valve 4 is arranged at the lower end of the crucible 6 to control the flow of the semi-solid alloy melt to the shot chamber. A certain amount of 670 ° C ZL101A alloy liquid is poured into the stationary crucible 11 , covered with a lid 8 , allowed to stand for 10 to 20 s, the valve 10 is opened, and the superheated ZL101A alloy liquid flows into the draft tube 9 to prepare the crucible. In the middle 6, when the amount of alloy melt to be inflow reaches about 2/3 of the volume of the prepared crucible 6, the valve 10 is closed, the electromagnetic stirrer 1 is turned on, the nominal power of the electromagnetic stirrer is set to 1300 W, and the internal and external cooling controllers are controlled. The flow rate of the cooling medium in the middle 14 and 3 is such that the cooling rate of the melt is 5 ° C /min, and the temperature indicated by the thermocouple 13 is 580 to 600 ° C, and the semi-solid ZL101A aluminum alloy slurry can be obtained. The electromagnetic stirrer 1 and the internal and external cooling controllers 14, 3 are closed, the valve 4 is opened, and the semi-solid ZL101A aluminum alloy slurry 7 is introduced into the extrusion cylinder 22 through the draft tube 5, and the temperature of the draft tube 5 is controlled at 500°. C, the extrusion mold right type 20, the extrusion mold left type 21, the extrusion barrel 22 and the extrusion rod 23 are preheated at a temperature of 250 ° C, and the valve 4 to be opened is closed for about 5 seconds after the semi-solid slurry is completely discharged. Valve 4, while the extrusion rod 23 presses the semi-solid slurry 7 into the extrusion mold right type 20 and the extrusion mold left The cavity between 21, press forming for about 4~8s, then take out the extrusion to complete the rheological extrusion casting of a semi-solid ZL101A aluminum alloy slurry, and open the valve 10 while rheologically pressing, which will overheat The ZL101A alloy liquid flows into the preparation crucible 6 and enters the next rheological extrusion casting.

Referring to Figures 1, 4, and 7, this is a process flow and apparatus provided in accordance with the above technical features. The superheated ZL101A aluminum alloy melt is melted by melting 坩埚12, and the enthalpy 12 is an electromagnetic induction heating furnace. The heat preservation performance is good, and the ZL101A alloy melt can ensure high temperature control precision, and the temperature control precision is ±10°C. The stationary crucible 11 is a crucible with excellent heat preservation performance, and the lower end opening is connected with the draft tube 9, and the bottom of the crucible 11 is open and a valve 10 is provided to control the flow of the alloy melt in the stationary crucible to the preparation crucible 6. The static enthalpy 11 can provide a sufficient amount of alloy liquid for preparing the crucible 6, and the static enthalpy 11 can ensure that the temperature of the alloy melt is 5 to 200 ° C above the liquidus, and the temperature control precision is ±10. The upper part of the draft tube 9 is connected to the stationary crucible 11, and the lower opening is opened into the alloy melt in the preparation crucible 6. The outside of the draft tube 9 is wound around a resistance heater which heats the temperature of the draft tube to 400. °C, the preparation crucible 6 is placed inside the thermal insulation system 2, and the top cover 8 is provided with excellent heat insulation performance, the inner diameter of the preparation crucible 6 is 08O X 480 mm, and the cooling medium output pipe 14_2 of the internal cooling controller 14 adopts a spiral mechanism. , as shown in Figure 4, the material For graphite, the preheating temperature is 300 ° C, the pitch is high L' is 10 mm, the thread height h' is 5 mm, and the distance between the outer wall of the thread and the inner side wall of the preparation is 10 mm. The distance between the bottom of the internal cooling controller cooling medium output pipe 14-2 and the inner wall of the preparation crucible is 40. The outer diameter of the cooling medium input pipe 14-1 of the internal cooling controller is 025, the pipe thickness is 3, the material is stainless steel, and the temperature is Room temperature. The thermal insulation system 2 is a nearly closed cylindrical structure that is hollow and has a top connected to the lid 8. It is surrounded by a good insulation material. This insulation system ensures that the alloy melt in the preparation crucible is slowly cooled at a cooling rate of l-150 ° C / min. The external cooling controller 3 surrounds the outside of the preparation crucible 6 and is spaced apart. Preparing the outer wall of the crucible 20, the ventilation duct wall of the external cooling controller 3 is provided with a ventilation hole, the diameter of the small hole is 4, and the cooling medium flow rate of the external cooling controller 3 is adjusted to make the outer wall cooling rate of the preparation crucible is l-150 ° C / min, The cooling medium is room temperature air. The continuous casting equipment consists of a tundish 24, a crystallizer 25, a cooling water nozzle 26 and a traction mechanism 27. The draft tube 5 is placed above the tundish 24, the diameter of the draft tube 5 is 072 mm, the inner dimension of the tundish is 240 X 120 X 80 mm, and the draft tube 5 is connected to the lower port of the preparation crucible 6 to prepare the lower mouth of the crucible 6 A valve 4 is provided to control the flow of the semi-solid alloy melt to the injection chamber. The ZL101A alloy liquid at 670 ° C is poured into the stationary crucible 11 , covered with a lid 8 , left to stand for 10 20 s, and the valve 10 is opened, so that the superheated ZL101A alloy liquid flows into the guide tube 9 to prepare the crucible 6 and internal cooling. The controller cools the gap between the threads of the medium output pipe 14-2, simultaneously opens the electromagnetic stirrer 1, sets the nominal power of the electromagnetic stirrer to 1300W, and controls the flow rate of the cooling medium in the internal and external cooling controllers. The cooling rate of the melt is 5 ° C / min, so that the alloy melt will be subjected to strong electromagnetic stirring while flowing in the gap. When the temperature of the alloy slurry indicated by the thermocouple 13 is lowered to 60 CTC, the semi-solid can be obtained. ZL101A aluminum alloy slurry 7 These aluminum alloy slurry 7 flows into the tundish 24 through the draft tube 5, and then is continuously cast into a semi-solid metal under the action of the crystallizer 25 of the continuous casting machine, the cooling water nozzle 26, and the traction mechanism 27. And alloy blank 28. Through the above-described repeated operations, the semi-solid billets 28 are continuously obtained, and these billets can be used as a semi-solid billet for thixoforming.

Referring to Figures 1, 2, and 8, this is a process flow and apparatus provided in accordance with the above technical features. The superheated ZL101A aluminum alloy melt is melted by melting 坩埚12, and the enthalpy 12 is an electromagnetic induction heating furnace. The heat preservation performance is good, and the ZL101A alloy melt can ensure high temperature control precision, and the temperature control precision is ±10°C. The stationary crucible 11 is a crucible with excellent heat preservation performance, and the lower end opening is connected with the draft tube 9, and the bottom of the crucible 11 is open and a valve 10 is provided to control the flow of the alloy melt in the stationary crucible to the preparation crucible 6. The static enthalpy 11 can provide a sufficient amount of alloy liquid for the preparation of 坩埚6, which ensures that the temperature of the alloy melt is 5 200 V above the liquidus, and the temperature control accuracy is ±10. The upper part of the draft tube 9 is connected to the stationary crucible 11, and the lower opening is opened into the alloy melt in the preparation crucible 6. The outside of the draft tube 9 is wound with an electric resistance heater which heats the temperature of the draft tube to 400. °C Preparation crucible 6 is placed inside the thermal insulation system 2, and the inner diameter of the crucible 6 is prepared to be 8O X 16Omm, and the crucible cover 8 having excellent heat insulation performance is prepared. The cooling medium output pipe 14-2 of the internal cooling controller 14 is as shown in the figure The structure shown in 2 has an outer diameter of 06Omm, is made of graphite, and has a preheating temperature of 300 °C. The outer wall of the internal cooling controller cooling medium output pipe 14-2 is 10 mm away from the inner side wall of the preparation crucible. The bottom of the internal cooling controller cooling medium output pipe 14-2 is 40 mm from the inner wall of the bottom of the preparation crucible. The cooling medium input pipe 14-1 of the internal cooling controller has an outer diameter of 025, a pipe thickness of 3 mm, a material of stainless steel, and a temperature of room temperature. The thermal insulation system 2 is a nearly closed cylindrical structure that is hollow and has a top connected to the lid 8. It is surrounded by a good thermal insulation material. This insulation system ensures that the alloy melt in the preparation crucible is slowly cooled at a cooling rate of 150 ° C / min. The external cooling controller 3 is wound around the outside of the preparation crucible 6 and is prepared. 20mm outer wall of the crucible, a small ventilation hole is formed in the cooling duct wall of the external cooling controller 3, the diameter of the small hole is 4mm, and the cooling medium flow rate of the external cooling controller 3 can be adjusted to make the outer wall cooling rate of the outer wall of the preparation crucible 150°C/min. The cooling medium is room temperature air. The placement of the draft tube 5 above the forging die facilitates smooth flow of the slurry into the cavity 29 of the forging die 30. The upper end of the draft tube 5 is connected to the lower port of the preparation crucible 6, and a valve 4 is arranged at the lower end of the preparation crucible 6, and the flow of the semi-solid alloy melt to the forging model chamber 29 is controlled. A certain amount of ZL101A alloy liquid of 670 ° C is poured into the stationary crucible 11 , covered with a lid 8 , left to stand for 10 20 s, the valve 10 is opened, and the superheated ZL101A alloy liquid flows into the preparation crucible along the draft tube 9 . 6. When the amount of alloy melt to be flowed reaches about 2/3 of the volume of the prepared crucible 6, close the valve 10, turn on the electromagnetic stirrer 1, set the nominal power of the electromagnetic stirrer to 1300W, and control the internal and external cooling controllers. The flow rate of the cooling medium in 14 3 is such that the cooling rate of the melt is 5 ° C / min, and the temperature indicated by the thermocouple 13 is 590 ° C, and the semi-solid ZL101A aluminum alloy slurry can be obtained. At this time, the electromagnetic stirrer is turned off. 1 and internal and external cooling controller 3 14, open the valve 4, the semi-solid ZL101A aluminum alloy slurry 7 flows into the forging model cavity 29 through the draft tube 5, the temperature of the draft tube 5 is controlled at 500 ° C, forging the model cavity The preheating temperature of 29 is 250 ° C, and after the valve 4 is opened for about 5 s, the semi-solid slurry 7 is completely discharged, the valve 4 is closed, and the mold of the forging machine is started to form a semi-solid metal and an alloy slurry, and pressure forming is performed. About 4 8s, then take out the forged piece, Into a semi-solid alloy slurry rheology ZL101A forging, forging rheology while opening the valve 10, the liquid flows into the superheated alloy prepared ZL101A crucible 6, rheology forging into the next time.

The apparatus for carrying out the invention is suitable for preparation and molding of semi-solid slurry of aluminum-based alloy, and is also suitable for magnesium-based alloy, zinc-based alloy, copper-based alloy, nickel-based alloy, cobalt-based alloy and iron-based alloy and Preparation and shaping of semi-solid slurries of composite materials.

The main embodiment of the method for producing a semi-solid metal rheological slurry or blank of the present invention is:

As shown in Fig. 1, the melt of the A357 aluminum alloy was melted by melting the crucible 12, and the liquidus temperature of the A357 aluminum alloy was 613. C. The melt temperature was controlled at 650 °C. The crucible 6 is prepared as a cylindrical stainless steel vessel, the internal cooling controller 14 is made of high-purity graphite, the outer diameter of the internal cooling controller is 40 mm, and the inner wall diameter of the crucible 6 is 80. Thus, the inner side wall of the crucible 6 and the internal cooling controller are prepared. The annular gap formed between the outer walls of 14 has a size of 20 mm. Will prepare 坩 After the 埚6 and the internal cooling controller 14 are preheated to 200 ° C in the holding furnace and quickly taken out, the valve 10 is opened, and the superheated A357 aluminum alloy melt flows along the draft tube 9 into the ring formed in the crucible. Strong agitation in the gap, the input power of the stirrer is 1200W, and the stirring frequency is 50Hz. The cooling medium input to the internal cooling controller 14 and the external cooling controller 3 is room temperature air, the flow rate is 30 liters/min, and the temperature difference between the inside and the outside of the slurry can be controlled at ± 3 °C. When the slurry temperature is cooled to 600 ° C, a semi-solid A357 aluminum alloy slurry having a solid phase fraction of about 0.35 is obtained, and the slurry structure is as shown in FIG. 9, FIG. 10 and FIG. Figure 9 is a quenched structure of the side of the semi-solid A357 aluminum alloy slurry prepared by the present invention, wherein the light-colored region is spherical nascent - Α /, the dark region is a solidified eutectic liquid; Figure 10 is a semi-solid prepared by the present invention; Quenched structure in the middle of Α357 aluminum alloy slurry, the light-colored area is spherical and the dark area is solidified eutectic liquid; Figure 11 is the quenched structure of the semi-solid Α357 aluminum alloy slurry center prepared by the present invention, light-colored area It is a globular nascent Α/, and the dark area is a solidified eutectic liquid. At this time, the slurry can be directly transferred to a die casting machine or a forging machine and an extruder to form. Or it is completely solidified in the preparation crucible as a raw material for thixoforming. Industrial application

The apparatus and method of the present invention are suitable for preparation of aluminum-based alloys and composite semi-solid pastes or blanks thereof, and also for magnesium-based alloys, copper-based alloys, zinc-based alloys, iron-based alloys and other non-ferrous metal alloys and Preparation of composite semi-solid slurry or blank.

Claims

Rights request

1. A device for preparing a semi-solid metal rheological slurry or blank by a ring-slit electromagnetic stirring, the device comprising a preparation crucible, an external cooling controller, an insulation system, and an external cooling system are arranged in the outer periphery of the preparation crucible a magnetic stirrer; a static raft is disposed on the upper portion of the preparation raft, and the static raft passes through the heat-guiding cover on the preparation raft through the bottom of the guide raft to communicate with the preparation raft, and the enthalpy is disposed on the upper portion of the stationary raft; a draft tube is disposed at the bottom of the preparation crucible, and the diversion tube at the bottom of the preparation crucible and the diversion tube at the bottom of the crucible have a valve; wherein: the middle portion of the preparation crucible is There is an internal cooling controller, and the outer wall of the internal cooling controller forms an annular gap with the inner side wall of the preparation crucible.

2. The apparatus for preparing a semi-solid metal rheological slurry or blank according to the annular seam electromagnetic stirring according to claim 1, wherein: the draft tube for preparing the bottom of the crucible is connected to the injection chamber of the die casting machine, A punch is disposed in one side of the shot chamber, and the other side of the shot chamber is connected to a die-casting fixed mold and a die-casting movable mold.

3. The apparatus for preparing a semi-solid metal rheological slurry or blank according to the annular seam electromagnetic stirring according to claim 1, wherein: the draft tube for preparing the bottom of the crucible is connected to the extrusion tube of the extruder, A squeeze rod is disposed in one side of the extrusion barrel, and the other side of the extrusion barrel is connected to the extrusion mold right type and the extrusion mold left type.

4. The apparatus for preparing a semi-solid metal rheological slurry or blank according to the annular seam electromagnetic stirring according to claim 1, wherein: the draft tube for preparing the bottom of the crucible is connected to the tundish of the continuous casting machine, in the middle The package is connected to the crystallizer, and a plurality of cooling water nozzles are arranged around the outlet of the crystallizer, and a lowering device outside the outlet of the crystallizer has a traction mechanism.

5. The apparatus for preparing a semi-solid metal rheological slurry or blank according to the annular seam electromagnetic stirring according to claim 1, wherein: the draft tube for preparing the bottom of the crucible is connected to the forged mold cavity in the forging die.

6. Apparatus for preparing a semi-solid metal rheological slurry or blank by circumferential seam electromagnetic stirring according to any one of claims 1 to 5, wherein: said internal cooling controller is internally connected thereto The cooling passage of the cooling medium is composed of a central tube and an outer sleeve thereof. The upper end of the central tube is a cooling medium input port, the lower end of the central tube is connected to the outer sleeve, and the central tube constitutes a cooling medium input passage; The upper port is the cooling medium output port, and the outer casing constitutes a cooling medium output channel.

7. The apparatus for preparing a semi-solid metal rheological slurry or blank by the circumferential seam electromagnetic stirring according to claim 1, wherein the preparation of the crucible has a circular, elliptical or square cross-sectional shape.

8. The apparatus for preparing a semi-solid metal rheological slurry or blank according to the annular seam electromagnetic stirring according to claim 6, wherein: the shape of the cooling medium input passage along the radial direction is the transverse direction of the center tube. The cross section is circular, elliptical, square or trapezoidal; the cooling medium input passage, that is, the central tube has a straight tubular shape along the axial direction. Shape or curved tube shape.

9. The apparatus for preparing a semi-solid metal rheological slurry or blank according to the circumferential seam electromagnetic stirring according to claim 8, wherein the shape of the cooling medium output passage along the radial direction is an outer sleeve. The shape of the cross section is circular, elliptical, square or trapezoidal; the cooling medium output passage, that is, the shape of the outer sleeve along the axial direction is a straight tube shape, a serpentine shape, a spiral tube shape, a wave tube shape or Other curved tube shapes; or the inner wall of the outer sleeve is shaped like a straight tube wall in the axial direction and the outer wall has a spiral or wave shape along the axial direction.

10. The apparatus for preparing a semi-solid metal rheological slurry or blank according to the invention, wherein: the material of the cooling medium input channel is austenitic stainless steel, titanium, molybdenum, Non-magnetic metal materials such as cobalt, chromium, nickel or copper, or non-metallic materials such as graphite, ceramic or corundum; the output channels of the cooling medium are non-magnetic such as austenitic stainless steel, titanium, molybdenum, cobalt, chromium, nickel or copper. a metal material, or a non-metallic material such as graphite, ceramic or corundum; the material for preparing the crucible is austenitic stainless steel, non-magnetic metal material such as titanium, molybdenum, cobalt, chromium, nickel or copper, or graphite, ceramic or corundum Non-metallic materials.

11. The apparatus for preparing a semi-solid metal rheological slurry or billet according to claim 6, wherein: the inner passage of the cooling medium input passage is an inner diameter of 2 1000. That is, the outer diameter of the outer casing is 5 1000

12. Apparatus for preparing a semi-solid metal rheological slurry or blank by circumferential seam electromagnetic stirring according to claim 6 or claim 7, wherein: the outer wall of the internal cooling controller is the outer wall of the cooling medium output passage and the preparation of the crucible 5 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300 300

13. Apparatus for producing a semi-solid metal rheological slurry or blank by circumferential-stitch electromagnetic stirring according to claim 6, wherein: the outer wall of said cooling medium output passage has a spiral shape along the axial direction. , the pitch is 5 100mm, the thread height is 2 100mm

14. Apparatus for producing a semi-solid metal rheological slurry or blank by circumferential-stitch electromagnetic stirring according to claim 6, wherein: the outer wall of said cooling medium output passage has a wave shape along the axial direction. , its pitch is

5 100mm, corrugated height is 2 100mm

15. The apparatus for preparing a semi-solid metal rheological slurry or blank according to the annular seam electromagnetic stirring according to claim 6, wherein: the cooling medium passing through the cooling passage is air, nitrogen, argon, tap water or the like. The liquid is cooled and the temperature of the cooling medium is room temperature.

16. A method of preparing a slurry or blank of a semi-solid metal or alloy using the apparatus of claim 1. The invention is characterized in that: using the device of claim 1, a liquid metal or alloy liquid higher than the liquidus temperature of 5 to 200 ° C is poured into the annular gap formed between the inner wall of the crucible and the outer wall of the inner cooling controller. Medium, and the electromagnetic stirrer is turned on to stir the liquid metal or the alloy liquid in the annular gap to prepare the semi-solid slurry, and simultaneously to the external cooling controller and the internal cooling controller to pass the room temperature temperature cooling medium, The cooling rate is 1~150 °C/min, which makes the temperature field of the preparation of the semi-solid slurry more uniform, thereby obtaining a fine and uniform semi-solid slurry structure, and controlling the temperature of the semi-solid slurry below its liquidus The temperature is higher than the temperature of its solidus line.

17. The method according to claim 16, wherein: the flow rate of the cooling medium introduced in the internal cooling controller and the external cooling control is 0 to 200 liters / min, and ≠0.

18. The method of claim 16 wherein: said electromagnetic stirrer employs an inductive AC rotary electromagnetic stirrer at a frequency of 5 to 100 Hz.

19. The method according to claim 16, wherein: during the preparation of the semi-solid slurry, the temperature difference between the inside and the outside of the semi-solid slurry is controlled within ± 3 ° C, and the temperature difference between the inside and the outside of the semi-solid slurry is internal. The difference between the temperature of the semi-solid slurry of the outer wall of the cooling controller and the temperature of the semi-solid slurry at the inner side wall of the crucible.

20. The method according to claim 16, wherein: the semi-solid slurry prepared is a semi-solid aluminum-based alloy slurry, a semi-solid magnesium-based alloy slurry, a semi-solid zinc-based alloy slurry, and a semi-solid copper. Any of a base alloy slurry, a semi-solid nickel-based alloy slurry, a semi-solid cobalt-based alloy slurry, and a semi-solid iron-based alloy slurry; or a semi-solid aluminum-based composite slurry, a semi-solid magnesium-based composite material Slurry, semi-solid zinc-based composite slurry, semi-solid copper-based composite slurry, semi-solid nickel-based composite slurry, semi-solid cobalt-based composite slurry, and semi-solid iron-based composite slurry One.

21. The method according to claim 20, wherein: the semi-solid slurry is completely solidified in the preparation crucible to obtain a semi-solid aluminum alloy billet, a semi-solid magnesium alloy billet, a semi-solid zinc alloy billet, and a half. Any one of a solid copper alloy billet, a semi-solid nickel alloy billet, a semi-solid cobalt alloy billet and a semi-solid iron-based alloy billet; or a semi-solid aluminum matrix composite billet, a semi-solid magnesium matrix composite billet, a half a blank of a solid zinc-based composite material, a blank of a semi-solid copper-based composite material, a blank of a semi-solid nickel-based composite material, a blank of a semi-solid cobalt-based composite material, and a blank of a semi-solid iron-based composite material, The above blank can be used as a semi-solid thixoforming original blank.

22. The method according to claim 16, wherein: during the preparation of the semi-solid slurry, an annular gap formed between the inner wall of the crucible and the outer wall of the inner cooling controller is introduced to avoid or reduce the metal or alloy. An oxidizing shielding gas which is argon, nitrogen or helium.