WO2020237865A1 - 一种有色金属及其合金电磁半连铸装置 - Google Patents

一种有色金属及其合金电磁半连铸装置 Download PDF

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Publication number
WO2020237865A1
WO2020237865A1 PCT/CN2019/102802 CN2019102802W WO2020237865A1 WO 2020237865 A1 WO2020237865 A1 WO 2020237865A1 CN 2019102802 W CN2019102802 W CN 2019102802W WO 2020237865 A1 WO2020237865 A1 WO 2020237865A1
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Prior art keywords
inner sleeve
mold
excitation coils
bodies
excitation
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PCT/CN2019/102802
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English (en)
French (fr)
Inventor
乐启炽
王航
贾永辉
胡成路
宁少晨
李小强
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东北大学
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/001—Continuous casting of metals, i.e. casting in indefinite lengths of specific alloys
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/04—Continuous casting of metals, i.e. casting in indefinite lengths into open-ended moulds
    • B22D11/0406—Moulds with special profile
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/10—Supplying or treating molten metal
    • B22D11/11—Treating the molten metal
    • B22D11/114—Treating the molten metal by using agitating or vibrating means
    • B22D11/115—Treating the molten metal by using agitating or vibrating means by using magnetic fields
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/14—Plants for continuous casting

Definitions

  • the invention belongs to the field of metal material preparation, and specifically relates to an electromagnetic semi-continuous casting device for non-ferrous metals and alloys thereof.
  • Semi-continuous casting is currently the main method for preparing metal ingots in industrial production; traditional direct water-cooled semi-continuous casting (traditional DC method) is to evenly introduce molten metal into the crystallizer, under the action of water cooling the crystallizer A solid solidified shell is formed, and then the starter head drives the solidified part to move down at a certain speed. When the solidified part leaves the mold, it will be affected by the secondary cooling water, and the solidified layer of the ingot is also It moves slowly to the center and completely solidifies and crystallizes.
  • traditional direct water-cooled semi-continuous casting traditional DC method
  • traditional DC method traditional DC method
  • the starter head drives the solidified part to move down at a certain speed.
  • the solidified part leaves the mold, it will be affected by the secondary cooling water, and the solidified layer of the ingot is also It moves slowly to the center and completely solidifies and crystallizes.
  • the ingot As the molten metal continuously flows into the mold, the ingot is continuously solidified and formed in the mold; this method increases labor productivity, improves working conditions, and increases The length of the ingot is increased, and the geometric loss of the cutting head and the tail is reduced; however, the ingots produced by traditional semi-continuous casting have the disadvantages of coarse grains, severe segregation, and poor surface quality of the ingots, which make the material loss rate greatly increase.
  • the basic principle of electromagnetic casting technology is to pass an alternating current into the excitation coil to generate an alternating magnetic field.
  • the alternating magnetic field acts on the molten metal through the inner sleeve of the mold, and induces current in the molten metal, induced current and alternating magnetic field
  • the electromagnetic force generated by the function plays the role of stirring the melt, uniforming the flow field, temperature field and solute field of the melt, thereby making the crystal grain of the ingot refined and improving the surface quality.
  • the permeability of the crystallizer should be good to ensure the electromagnetic pressure required for soft contact on the surface of the ingot; (2) The crystallizer should have a good cooling effect to ensure that the melt is crystallized A solidified shell of a certain thickness is formed in the vessel to avoid accidents such as pull-out; (3) The mold must have a certain strength, especially the yield strength, because the huge temperature gradient will produce great thermal stress, which is very easy Deformation and thermal stress cracks occur, causing damage to the mold.
  • the copper inner sleeve can basically meet the requirements of good cooling effect and strength, but due to the high shielding of copper to the magnetic field, the alternating magnetic field generated by the excitation coil will be larger when passing through the copper inner sleeve of the mold Loss, the electromagnetic utilization rate is greatly reduced, resulting in a poor stirring effect of the electromagnetic field on the melt; in order to improve the permeability of the mold, some scholars have successively developed a slotted electromagnetic continuous casting mold.
  • This kind of crystallizer cuts several gaps uniformly along the upper part of the crystallizer wall in a certain direction, so that the electromagnetic field can directly act on the melt through the gaps, thereby reducing the shielding effect of the crystallizer wall on the magnetic field.
  • slitting including equal slitting, non-equal slitting, full-body slitting, non-full-body slitting and oblique slitting.
  • Seamless crystallizer can be divided into two design forms, one is segmented seamless crystallizer, and the other is integral seamless crystallizer.
  • Chinese patent 201811273062.4 provides a two-stage copper alloy crystallizer with high permeability and soft contact. The upper part adopts high permeability copper alloy to increase the permeability, and the lower part adopts pure copper material. The thickness of the mould wall is 20mm-30mm.
  • connection between the lower part and the lower part is welded by pure copper TIG, but the mold has the difficulty of smooth connection between the two materials and the difference in thermal properties is likely to cause serious defects in the ingot; the integral seamless soft contact crystal
  • the mold is filled with high-resistivity powder between high-conductivity copper or copper alloy, and processed by hot isostatic pressing into a whole; this kind of mold has improved strength, but it still has not solved the problem. Magnetic problem.
  • the present invention provides an electromagnetic semi-continuous casting device for non-ferrous metals and their alloys, which adjusts the structure of the mold and reduces the thickness of the traditional copper inner sleeve, so that the magnetic field generated by the excitation coil acts more on the molten metal Medium and uniform distribution to achieve technical goals such as refining the ingot grains, eliminating surface defects, reducing the segregation of alloy components, and improving surface quality.
  • the non-ferrous metal and its alloy electromagnetic semi-continuous casting device of the present invention includes a mold and an excitation coil system;
  • the mold is composed of an upper cover plate, a mold shell, a copper inner sleeve and a mold water sealing plate, and the upper part of the mold shell is provided with Cooling water inlet, the bottom of the copper inner sleeve is provided with two cold water spray holes;
  • the excitation coil system is fixed in the cooling water tank between the mold shell and the copper inner sleeve, and consists of fixing bolts, coil pressing plates, coil support blocks and excitation coils ;
  • the outer side wall of the copper inner sleeve is provided with or without reinforcing ribs.
  • the reinforcing ribs and the copper inner sleeve are an integral structure, and the reinforcing ribs are composed of multiple circular ring bodies or It is composed of a row of arc-shaped bodies, or is composed of a plurality of circular ring bodies and a plurality of cylindrical bodies; the thickness of the side wall of the copper inner sleeve is 6-20mm; the excitation coil is divided into two groups, two Each group of excitation coils in the group of excitation coils is connected in series and connected to a power source.
  • the vertical cross section of the reinforcing rib is rectangular, trapezoidal on the side or semicircle on the side; when the vertical cross section is rectangular, the lateral thickness along the copper inner sleeve is 3-9mm and the height is 6-20mm; When the vertical section is a trapezoid placed sideways, the upper side of the trapezoid is 3-10mm long, the lower side is 6-20mm long, and the height is 3-9mm; when the vertical section is semicircular, the semicircular diameter is 6-20mm.
  • the vertical section of the inner space of the copper inner sleeve is an isosceles trapezoid or an inverted isosceles trapezoid
  • the inner wall of the copper inner sleeve is provided with a plating layer, and the plating layer is a chromium plating layer, a Ni-Fe plating layer, a Ni-Co alloy plating layer, a Ni-Fe-W-Co alloy plating layer or a Ni-P alloy plating layer.
  • the material of the mold shell is steel
  • the material of the upper cover plate and the mold water sealing plate is paramagnetic stainless steel
  • the paramagnetic stainless steel is 304 stainless steel, 321 stainless steel or 347 stainless steel.
  • the vertical distance between two adjacent circular ring bodies is 15-50mm; when the reinforcing rib is composed of multiple rows of arc-shaped bodies, the distance between two adjacent rows of arc-shaped bodies The vertical spacing is 15-50mm, and the horizontal spacing between two adjacent arc-shaped bodies in each row of arc-shaped bodies is 5-25mm; when the stiffener is formed into a grid by multiple toroids and multiple cylindrical bodies, two adjacent ones The vertical spacing of the ring body is 15-50mm.
  • the columnar body is divided into a long columnar body and a short columnar body. The two ends of the long columnar body are respectively connected with the uppermost ring body and the lowermost ring body, and the short columnar The two ends of the body are respectively connected with two adjacent ring bodies.
  • the second cold water nozzle has a circular cross-section with a diameter of 0.5 to 3.5 mm.
  • the individual excitation coils are arranged from top to bottom with the axis of the mold as the axis.
  • each coil in the two sets of excitation coils is arranged in the same direction, that is, the alternating current flowing into each coil has the same flow direction, ensuring that the magnetic field lines of the magnetic field generated by each coil are the same.
  • the electromagnetic semi-continuous casting method of non-ferrous metals and their alloys of the present invention adopts the above-mentioned device and performs the following steps:
  • the two sets of excitation coils are supplied with alternating current or pulse current through the power supply, so that each group of excitation coils generates a set of alternating electromagnetic signals or pulse electromagnetic signals, each forming a magnetic field; the two sets of excitation coils are connected
  • the phase difference of the alternating current or pulse current is 90°, and the resulting phase difference magnetic field acts on the molten metal in the mold;
  • the thickness of the side wall of the copper inner sleeve is 8-20 mm.
  • the thickness of the side wall of the copper inner sleeve when the diameter of the ingot is less than 150mm, the thickness of the side wall of the copper inner sleeve is at least 8mm, when the diameter of the ingot is between 150 and 300mm, the thickness of the side wall of the copper inner sleeve is at least 10mm, and when the ingot diameter is greater than At 300mm, the side wall thickness of the copper inner sleeve should be at least 12mm.
  • the hole diameter of the secondary cold water nozzle is 1 ⁇ 3.5mm; when the metal melt is aluminum, magnesium, aluminum alloy or magnesium alloy, the diameter of the secondary cold water nozzle hole is 0.5 ⁇ 3.5mm. 2.5mm.
  • the current intensity is 50-200A and the frequency is 10-30Hz; when the pulse current is applied, the duty ratio is 10-30%.
  • the device and method of the invention have strong applicability to round ingots or slabs.
  • the device and method of the present invention are also applicable to electromagnetic semi-continuous casting of steel.
  • the main technical principle of the present invention is: in view of the shortcoming of the small magnetic field generated by a single coil in the traditional electromagnetic continuous casting process, the excitation coil is divided into two groups and the phase difference current with a phase difference of 90° is passed through the adjustment coil.
  • the height and the axial distance between the coils can significantly increase the strength and action area of the magnetic field in the molten metal, and increase the electromagnetic utilization; for the traditional copper inner sleeve, the thickness of the inner sleeve is large, which makes the magnetic field loss in the inner sleeve larger
  • the disadvantage of reducing the effect and the magnetic field strength in the melt is to reduce the thickness of the inner sleeve, and apply different forms and distributions of reinforcing ribs for different casting alloys to increase the strength of the inner sleeve; the above method can be significantly increased Acting on the strength of the magnetic field and the area of action of the melt, it produces fine-grained, uniform ingots with good surface quality.
  • the present invention can achieve the following positive effects:
  • the thickness of the copper inner sleeve is smaller than that of the traditional inner sleeve, which significantly improves the permeability and the electromagnetic utilization rate. It has a positive effect on the semi-continuous casting of copper alloy, aluminum alloy, magnesium alloy, steel and other metals;
  • the excitation coil can adjust the turns ratio and aspect ratio of the coil, adjust the position of the excitation coil, and adjust the parameters of the phase current applied by the coil (current intensity I, frequency f) ,
  • the generated differential phase magnetic field can effectively improve the electromagnetic utilization rate and have a large permeability of the melt, which has a positive effect on the uniform distribution of the magnetic field in the metal melt;
  • the device has compact structure, high safety, simple assembly and easy maintenance.
  • Figure 1 is a schematic diagram of the cross-sectional structure of the non-ferrous metal and its alloy electromagnetic semi-continuous casting device in embodiment 1 of the present invention; in the figure, 1. the upper cover plate of the mold, 2. the mold shell, 3. the cooling water inlet, and 4. Bolt, 5. Coil pressing plate, 6. Coil support block, 7. Mould sealing plate, 8. Excitation coil, 9. Fastening bolt, 10. Sealing ring, 11. Copper inner sleeve, 12. Second cold water spray hole , 13, torus body, 14, arc-shaped body, 15, long columnar body, 16, short columnar body;
  • Figure 2 is a schematic diagram of the copper inner sleeve structure in the embodiment of the present invention.
  • the reinforcing rib is composed of multiple circular ring bodies;
  • the reinforcing rib is composed of multiple rows of arc-shaped bodies, each row of arc-shaped The body has a number of single arc-shaped bodies, and each row of arc-shaped bodies is staggered in the vertical direction;
  • the stiffener is composed of a plurality of circular ring bodies and a plurality of columnar bodies forming a grid shape, and the columnar body is a long columnar body;
  • the reinforcing rib is composed of a plurality of circular ring bodies and a plurality of columnar bodies, and the columnar body is a short columnar body;
  • Figure 3 is a schematic diagram of the cross-sectional structure of the reinforcing rib in the embodiment of the present invention; in the figure, (a) the vertical cross-section is rectangular; (b) the vertical cross-section is trapezoidal; (c) the vertical cross-section is semicircular;
  • Figure 4 is a schematic diagram of the arrangement of excitation coils in the embodiment of the present invention; among them: (a) is the arrangement of two groups of excitation coils in sequence; (b) is the arrangement of two groups of excitation coils alternately;
  • Figure 5 is a cloud diagram of the magnetic induction intensity distribution in the molten metal with different excitation coil length-to-width ratios in Example 1 of the present invention; in the figure, (a) the excitation coil length-to-width ratio is 4:1; (b) the excitation coil length-to-width ratio 2:1; (c) the aspect ratio of the excitation coil is 1:1; (d) the aspect ratio of the excitation coil is 1:2; (e) the aspect ratio of the excitation coil is 1:4;
  • Fig. 6 is the Lorentz force distribution cloud diagram during one cycle after the two sets of coils are applied with the same phase pulse current in the embodiment 1 of the present invention; in the figure, T is the period; (a) 0.2T, (b) 0.4T , (C) 0.6T, (d) 0.8T, (e) 1T;
  • Fig. 7 is the Lorentz force distribution cloud diagram during one cycle after the pulse currents with a phase difference of 90° are applied to the two sets of coils in Example 1 of the present invention; in the figure, T is the period; (a) 0.2T, (b ) 0.4T, (c) 0.6T, (d) 0.8T, (e) 1T;
  • d is the diameter of the second cold water injection hole
  • L is the distance between two adjacent second cold water injection holes
  • Figure 9 is a macroscopic structure diagram of a ⁇ 300mm pure copper ingot prepared in the comparative test of Example 3 of the present invention and traditional DC casting; in the figure, (a) traditional DC casting; (b) Example 3 of the present invention;
  • Figure 10 is a photograph of the appearance of a ⁇ 300mm pure copper ingot prepared in a comparative test of Example 3 of the present invention and traditional DC casting; in the figure, (a) traditional DC casting; (b) Example 3 of the present invention;
  • Figure 11 is a macroscopic structure diagram of the AZ31 magnesium alloy prepared in the comparative test of Example 2 of the present invention and traditional DC casting; in the figure, (a) traditional DC casting; (b) Example 2 of the present invention;
  • Example 12 is a graph showing the macrosegregation curve of major elements in the radius direction of the AZ31 magnesium alloy prepared in a comparative test between Example 2 of the present invention and conventional DC casting; in the figure, (a) conventional DC casting; (b) Example 2 of the present invention.
  • the copper inner sleeve used in the embodiment of the present invention is composed of an upper flange and a side wall, and the upper flange and the side wall are an integral structure.
  • the thickness of the side wall of the copper inner sleeve is 6-20 mm.
  • the vertical cross section of the reinforcing rib is rectangular, trapezoidal on the side or semicircle on the side; the structure is shown in Figure 3; when the vertical cross section is rectangular, the lateral thickness along the outer side of the copper inner sleeve 3 ⁇ 9mm, height 6 ⁇ 20mm; when the vertical section is a trapezoid placed on the side, the upper side of the trapezoid is 3-10mm long, the lower side is 6-20mm, and the height is 3-9mm; when the vertical section is semicircular, semicircular The diameter is 6-20mm.
  • the inner side wall of the copper inner sleeve is provided with a plating layer, and the plating layer is a chromium plating layer, a Ni-Fe plating layer, a Ni-Co alloy plating layer, a Ni-Fe-W-Co alloy plating layer or a Ni-P alloy plating layer.
  • the material of the mold shell is steel
  • the material of the upper cover plate and the mold water sealing plate is paramagnetic stainless steel
  • the paramagnetic stainless steel is 304 stainless steel, 321 stainless steel or 347 stainless steel.
  • the vertical distance between two adjacent circular ring bodies 13 is 15-50mm; when the reinforcing rib is composed of multiple rows of arc-shaped bodies 14, two adjacent The vertical spacing of the rows of arc-shaped bodies 14 is 15-50mm, and the horizontal spacing of two adjacent arc-shaped bodies 14 in each row of arc-shaped bodies 14 is 5-25mm; when the reinforcing rib is composed of multiple circular ring bodies 13 and multiple columnar bodies In the case of a grid, the vertical distance between two adjacent ring bodies is 15-50 mm.
  • the columnar body is divided into a long columnar body 15 and a short columnar body 16. The two ends of the long columnar body 15 are connected to the uppermost circle respectively.
  • the ring body is connected to the bottom ring body 13, and the two ends of the short columnar body 16 are respectively connected to two adjacent ring bodies 13; the structure is shown in FIG. 2.
  • the vertical section is an inverted isosceles trapezoid;
  • the vertical section is an isosceles trapezoid.
  • each coil in the two sets of excitation coils is arranged in the same direction, that is, the alternating current flowing into each coil flows in the same direction, which ensures that the magnetic field lines of the magnetic field generated by each coil are the same.
  • the excitation coils in each group of excitation coils exceeds 1, the excitation coils in each group are arranged up and down, as shown in Figure 4(a); or the individual excitation coils in each group of excitation coils alternate Arrangement, as shown in Figure 4(b).
  • the upper flange when the metal melt is copper or copper alloy, the upper flange has a thickness of 10-20 mm; when the metal melt is aluminum, magnesium, aluminum alloy or magnesium alloy, the upper flange has a thickness of 6-15 mm.
  • the copper inner sleeve is not provided with reinforcing ribs.
  • the magnet wire used in the excitation coil in the embodiment of the present invention is a commercially available double-layer polyimide-fluorine 46 composite film-coated rectangular copper wire.
  • the level of the lowest excitation coil monomer is higher than the height of the center of the liquid cavity of the molten metal in the mold.
  • the magnetic induction intensity inside the copper inner sleeve is 20-200 mT when the excitation coil generates a magnetic field.
  • the cross section of the second cold water nozzle hole is circular; when the metal melt is copper or copper alloy, the diameter of the second cold water nozzle hole is 1 ⁇ 3.5mm; when the metal melt is aluminum, magnesium, aluminum alloy or magnesium When alloying, the diameter of the second cold water nozzle hole is 0.5-2.5mm; when the metal melt is copper or copper alloy, the distance between two adjacent second cold water nozzle holes is 3 to 5 times the diameter of the second cold water nozzle hole; When the body is aluminum, magnesium, aluminum alloy or magnesium alloy, the distance between two adjacent secondary cooling water nozzle holes is 2 to 4 times the diameter of the secondary cooling water nozzle; the structure is shown in Figure 8.
  • the thickness of the side wall of the copper inner sleeve is 8-20 m.
  • the thickness of the side wall of the copper inner sleeve when the diameter of the ingot is less than 150mm, the thickness of the side wall of the copper inner sleeve is at least 8mm. When the diameter of the ingot is between 150 and 300mm, the thickness of the side wall of the copper inner sleeve is at least 10mm. When the diameter is greater than 300mm, the side wall thickness of the copper inner sleeve shall be at least 12mm.
  • the diameter of the second cold water nozzle hole is 1 ⁇ 3.5mm; when the metal melt is aluminum, magnesium, aluminum alloy or magnesium alloy, the diameter of the second cold water nozzle hole 0.5 ⁇ 2.5mm.
  • the current intensity is 50-200A and the frequency is 10-30Hz.
  • paramagnetic stainless steel is selected as the material of the upper cover plate and the sealing water plate, so that the phase difference magnetic field generated by the two sets of excitation coils can pass smoothly and the magnetic lines of force are not deformed.
  • the material of the mold shell is ordinary steel, so that the magnetic field It is not easy to pass through the mold shell, reducing the loss of the magnetic field in the outside world.
  • the thickness of the side wall of the copper inner sleeve is relatively thin, considering that there is a huge temperature gradient in the copper inner sleeve during the semi-continuous casting process, thermal deformation will occur.
  • the cross-sectional shape and different forms of reinforcing ribs strengthen the strength of the inner sleeve.
  • the current used is a phase difference current.
  • the phase difference currents are respectively fed into the two sets of excitation coils to generate a phase difference magnetic field to act on the metal melt; a set of excitation coils is fed with a current with an initial phase of 0° , The other set of coils is fed with a current with an initial phase of 90°; the axial distance between each excitation coil is adjusted by the height of the coil support block.
  • the non-ferrous metal and its alloy electromagnetic semi-continuous casting device includes a mold and an excitation coil system; the structure is shown in Figure 1.
  • the mold is composed of an upper cover plate 1, a mold shell 2, a copper inner sleeve 11, and a mold water sealing plate 7.
  • the upper part of the mold shell 2 is provided with a cooling water inlet 3, and the bottom of the copper inner sleeve 11 is provided with two cold water spray holes 12;
  • the vertical section of the inner space of the copper inner sleeve 11 is an inverted isosceles trapezoid
  • the upper part of the upper cover plate 1 of the crystallizer is fixed with the upper flange of the copper inner sleeve 11 by bolts, and is hermetically connected by a sealing ring 10;
  • the upper part of the mold shell 2 is fixedly connected with the upper cover plate 1 of the mold through the fastening bolt 9; the bottom of the mold shell 2 is fixedly connected with the mold water sealing plate 7 through the fastening bolt 9;
  • the mold water sealing plate 7 is ring-shaped, and is fixed with the mold shell 2 by fastening bolts 9 and is connected in a sealed manner by a sealing ring 10;
  • the excitation coil system is fixed in the cooling water tank between the mold shell 2 and the copper inner sleeve 11, and consists of a fixing bolt 4, a coil pressing plate 5, a coil support block 6 and an excitation coil 8;
  • the fixing bolt 4 is welded and fixed to the bottom of the mold shell 2; a number of coil pressing plates 5 are fixed on the fixing bolts 4; each excitation coil 8 and each coil support block 6 are arranged alternately up and down, and between two adjacent coil pressing plates 5 There is only one coil support block 6 between; the coil support block 6 and the excitation coil 8 are pressed and fixed by the fixing bolt 4, the coil pressing plate 5 and the bottom of the mold shell 2;
  • the outer side wall of the copper inner sleeve 11 is provided with reinforcing ribs 13.
  • the reinforcing ribs 13 and the side walls of the copper inner sleeve 11 are an integral structure.
  • the reinforcing ribs 13 are composed of multiple circular ring bodies, as shown in Figure 2(a). Show
  • the excitation coil 8 is divided into two groups, each of the two groups of excitation coils is connected in series, and each group is connected to a power source;
  • the results of the numerical simulation are shown in Figure 5; the simulation results show that changing the aspect ratio of the coil can effectively change the size and distribution of the magnetic induction intensity in the melt; the smaller the coil aspect ratio, the smaller the magnetic induction intensity in the melt Decrease, but the distribution area in the melt increases and the uniformity of the distribution is better;
  • the structure of the device is the same as that of Embodiment 1, the difference is: the axial distance between the two coils is 20-40mm, the vertical section of the inner space of the copper inner sleeve is an isosceles trapezoid, the diameter is 320mm, the thickness is 8mm, and no reinforcement is provided. Rib, the current flowing into the excitation coil is harmonic current;
  • the cooling water is first introduced into the cooling water tank, and the cooling water is sprayed from the second cooling water nozzle; the metal melt is introduced into the mold to make the level of the metal melt reach a predetermined height;
  • the metal melt is a non-ferrous metal or a non-ferrous metal alloy;
  • the two sets of excitation coils are fed with harmonic currents of different initial phases through the power supply, so that each set of excitation coils generates a set of electromagnetic signals, and each forms a harmonic magnetic field; the phase difference of the alternating currents through the two sets of excitation coils is 90 °, the formed difference-phase harmonic magnetic field acts on the molten metal in the mold;
  • the casting temperature is 720°C
  • the casting speed is 1.12mm/s
  • the cooling water volume is 10.5-12.5m 3 /h
  • the intensity of the phase current is 50-80A.
  • the frequency is 10 ⁇ 30Hz
  • the second cold water sprayed through the second cold water nozzle cools the ingot under the mold until the casting is completed;
  • the same magnesium alloy was prepared by traditional DC casting for comparative experiments; the macrostructure is shown in Figure 11, it can be seen from the figure that the columnar crystals of the traditional DC casting ingot are coarse, and the ingot grains obtained by the above method are fine and uniformly distributed; The comparison of the macro-segregation of the main elements in the ingot radius direction is shown in Figure 12. It can be seen from the figure that the macro-segregation of the ingot elements cast by the above method is smaller and more uniform than the traditional DC casting.
  • the structure of the device is the same as that of embodiment 1, the difference is:
  • the stiffener is composed of 5 rows of arc-shaped bodies, as shown in Figure 2(b);
  • Each group of excitation coils is composed of two excitation coils, the arrangement is shown in Figure 4(a); the axial distance of adjacent excitation coils is 30-50mm,
  • the vertical section of the inner space of the copper inner sleeve is an inverted isosceles trapezoid, with a side wall thickness of 10mm;
  • the casting temperature is 1180°C
  • the casting speed is 4m/h
  • the cooling water pressure is 34 ⁇ 38m 3 /h
  • there are two sets of excitation coils fixed in the mold the current intensity is 200A
  • the frequency is 20Hz
  • the duty cycle is 20%;
  • the macrostructure photo is shown in Figure 9; it can be seen from the figure that the columnar crystals of the ingots obtained by the method of this embodiment are smaller, and the small equiaxed crystal regions are significantly increased;
  • the appearance photo is shown in Fig. 10, which shows that the surface of the ingot obtained by traditional DC casting has obvious defects such as wrinkles, while the surface of the ingot obtained in this embodiment is smoother and has better surface quality.

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Abstract

一种有色金属及其合金电磁半连铸装置，包括结晶器和励磁线圈系统；结晶器铜制内套（11）的外侧壁上设有或不设有加强筋，当设有加强筋时，加强筋与铜制内套（11）为一体结构，加强筋由多个圆环体（13）组成，或者由多排弧形体（14）组成，或者由多个圆环体（13）和多个柱状体构成网格状；铜制内套（11）的侧壁厚度为6～20mm；励磁线圈系统中的励磁线圈（8）分为两组。

Description

一种有色金属及其合金电磁半连铸装置 技术领域
本发明属于金属材料制备领域，具体涉及一种有色金属及其合金电磁半连铸装置。
背景技术
半连续铸造是目前工业生产中制备金属铸锭的主要方法；传统直接水冷半连续铸造(传统DC法)是将熔化的金属熔体均匀地导入结晶器中，在通水冷却结晶器的作用下形成一层坚固的凝固壳，然后引锭头带动已经凝固的部分一起以一定的速度向下移动，当已凝固的部分脱离结晶器时会受到二次冷却水的作用，铸锭的凝固层也就缓慢的向中心移动，并完全凝固结晶，随着金属熔体不断地流入结晶器，铸锭也不断的在结晶器中凝固成型；这种方法提高了劳动生产率，改善了劳动条件，且增大了锭坯长度，减小了切头与切尾的几何损失；但传统的半连续铸造生产出的铸锭存在晶粒粗大、偏析严重、铸锭表面质量差等缺点，使材料的耗损率大大增加。
为了解决传统DC法存在的各种问题，国内外开发出了新型半连续铸造技术，其中主要有矮槽铸造、热顶铸造、气滑和气幕铸造、低液位半连续铸造与外场辅助铸造等，其中以在金属凝固过程中施加外场效果最为显著；目前施加的外场主要有电磁场与超声场，但是施加超声场这一方法由于超声在熔体中的衰减较大致使作用范围有限且超声杆直接作用于熔体导致污染等一系列问题导致无法大规模应用于工业生产；而电磁铸造技术具有非接触、无污染与细化凝固组织显著等一系列优点获得了业界的广泛认可。
电磁铸造技术的基本原理是向励磁线圈内通入交流电流产生交变磁场，交变磁场透过结晶器内套作用于金属熔体，在金属熔体中产生感应电流，感应电流与交变磁场作用产生电磁力起到搅拌熔体的作用，均匀熔体的流场、温度场与溶质场，从而使铸锭的晶粒细化、表面质量提高。但是该技术对结晶器有一定的要求：(1)结晶器的透磁率要好以保证铸锭表面软接触所需要的电磁压力；( 2)结晶器要具有良好的冷却效果以保证熔体在结晶器内形成一定厚度的凝固坯壳，避免发生拉漏等事故；(3)结晶器要具有一定的强度，尤其是屈服强度，因为在巨大的温度梯度下会产生极大的热应力，极易产生变形和热应力裂纹，造成结晶器的损坏。
目前对于铜制内套，可以基本满足冷却效果好与强度的要求，但由于铜对磁场的屏蔽性高，励磁线圈产生的交变磁场在穿过结晶器铜制内套时会有较大的损耗，使得电磁利用率大大降低，致使电磁场对熔体的搅拌效果较差；为了提高结晶器的透磁性，有学者陆续开发出了切缝式电磁连铸结晶器。这种结晶器是通过在结晶器壁上部沿一定方向均匀切割出数条缝隙，使电磁场能通过缝隙直接作用于熔体从而减小结晶器壁对磁场的屏蔽作用。切缝的形式多种多样，有均等切缝、非均等切缝、通体切缝、非通体切缝和倾斜切缝等。
中国专利CN200710190961、CN200920266196.3、CN02265157.8等表明，在结晶器内套上开设一定数目的切缝可使结晶器内的磁场强度增加，使结晶器的透磁性得到了极大的增加。但是由于切缝的存在，切缝式结晶器有着极大的缺陷：(1)熔体内的磁场分布变得更加复杂，切缝处与非切缝处的熔体所受的电磁力差异较大，这种差异容易使铸锭表面质量变差，影响铸锭的冶金质量；(2)切缝的存在破坏了结晶器的整体性，使结晶器的强度大大降低，为实际生产带来不稳定因素；(3)切缝使结晶器壁的每个金属片层相互独立，且在连铸过程中，结晶器会在高温的作用下产生热胀冷缩效应，切缝有被压缩或胀大的趋势，导致冷却水回路设计困难。
考虑到切缝式结晶器存在诸多缺点，许多研究者将目光投向了无缝式电磁铸造结晶器。无缝式结晶器可分为两种设计形式，一种是分段式无缝结晶器，一种是整体式无缝结晶器。中国专利201811273062.4提供了一种高透磁性软接触两段式铜合金结晶器，上部采用高透磁性铜合金以增加透磁性，下部采用纯铜材料，结晶器壁的厚度为20mm～30mm，上半部与下半部的连接处采用纯铜TIG焊接，但该结晶器存在两种材料连接处平滑衔接的困难且由于热物性的差异容易给铸锭带来严重缺陷；整体式无缝软接触结晶器是在高电导率的铜或铜质合金之间填充高电阻率的粉末，经热等静压烧结加工成一体；这种结晶器在强度上有 所提升，但仍没有解决大幅度提高透磁性的问题。
发明概述
技术问题
问题的解决方案
技术解决方案
针对目前电磁半连续铸造存在的各种问题，如结晶器内套存在切缝使强度降低、熔体中磁场分布复杂容易使表面质量变差、电磁场在熔体中的作用范围有限、磁场利用率较低等，本发明提供一种有色金属及其合金电磁半连铸装置，调整结晶器结构，减小传统铜制内套的厚度，使得励磁线圈所产生的磁场更多的作用于金属熔体中且均匀分布，实现细化铸锭晶粒，消除表面缺陷，减小合金成分的偏析，提升表面质量等技术目标。
本发明的有色金属及其合金电磁半连铸装置包括结晶器和励磁线圈系统；结晶器由上盖板、结晶器外壳、铜制内套和结晶器封水板组成，结晶器外壳上部设有冷却水入口，铜制内套底部设有二冷水喷孔；励磁线圈系统固定在结晶器外壳和铜制内套之间的冷却水槽内，由固定螺栓、线圈压板、线圈支撑块和励磁线圈组成；其中铜制内套的外侧壁上设有或不设有加强筋，当设有加强筋时，加强筋与铜制内套为一体结构，加强筋由多个圆环体组成，或者由多排弧形体组成，或者由多个圆环体和多个柱状体构成网格状；所述的铜制内套的侧壁厚度为6～20mm；所述的励磁线圈分为两组，两组励磁线圈中的每组励磁线圈串联，且各自与电源连接。
上述装置中，加强筋的垂直截面为矩形、侧放的梯形或侧放的半圆形；当垂直截面为矩形时，沿铜制内套向外的横向厚度3～9mm，高度6～20mm；当垂直截面为侧放的梯形时，梯形的上边长3～10mm，下边长6～20mm，高度3～9mm；当垂直截面为半圆形时，半圆形的直径6～20mm。
上述装置中，铜制内套的内部空间的垂直截面为等腰梯形或倒置的等腰梯形，等腰梯形的侧边或倒置的等腰梯形的侧边与轴线的夹角θ＝1°～8°。
上述装置中，铜制内套的内侧壁上设有镀层，镀层为铬镀层、Ni-Fe镀层、Ni-Co合金镀层、Ni-Fe-W-Co合金镀层或Ni-P合金镀层。
上述装置中，结晶器外壳的材质为钢，上盖板和结晶器封水板的材质为顺磁性不锈钢，顺磁性不锈钢选用304不锈钢、321不锈钢或347不锈钢。
上述装置中，当加强筋由多个圆环体组成时，相邻两个圆环体的垂直间距15～50mm；当加强筋由多排弧形体组成时，相邻两排弧形体的垂直间距15～50mm，每排弧形体中相邻两个弧形体的水平间距5～25mm；当加强筋由多个圆环体和多个柱状体构成网格状时，相邻两个圆环体的垂直间距15～50mm，所述的柱状体分为长柱状体和短柱状体，长柱状体的两端分别与最上方的圆环体和最下方的圆环体连接，短柱状体的两端分别与相邻的两个圆环体连接。
上述装置中，二冷水喷孔截面为圆形，孔径0.5～3.5mm。
上述装置中，两组励磁线圈中，两组励磁线圈的长宽比同时设为1∶N，或其中一组励磁线圈的长宽比为1∶N，则另一组励磁线圈的长宽比为N∶1，其中N＝1～5。
上述装置中，励磁线圈的匝数30～150，相邻两个励磁线圈的间距10～50mm；两组励磁线圈的匝数比为1∶N，其中N＝0.2～5；两组励磁线圈中的各个励磁线圈单体从上到下排列，且以结晶器轴线为轴。
上述装置中，两组励磁线圈中的每个线圈同向排布，即通入每个线圈中的交流电流的流向相同，保证每个线圈所产生的磁场的磁力线相同。
本发明的有色金属及其合金电磁半连铸方法是采用上述装置，按以下步骤进行：
(1)向冷却水槽内通入冷却水，冷却水从二冷水喷孔喷出；将金属熔体导入结晶器内，使金属熔体的液面达到预定高度；所述的金属熔体为有色金属或有色金属合金；
(2)通过电源对两组励磁线圈分别通入交变电流或脉冲电流，使每组励磁线圈各自产生一组交变电磁信号或脉冲电磁信号，各自形成一种磁场；两组励磁线圈通入的交变电流或脉冲电流的相位差为90°，形成的差相磁场作用于结晶器内的金属熔体；
(3)启动有色金属及其合金电磁半连铸装置，对金属熔体进行铸造，通过二冷水喷孔喷出的二冷水对结晶器下方的铸锭冷却，直至铸造完成。
上述方法中，当金属熔体为铜或铜合金时，铜制内套的侧壁厚度为8～20mm。
上述方法中，当铸锭直径小于150mm时，铜制内套的侧壁厚度至少8mm，当铸锭直径在150～300mm之间，铜制内套的侧壁厚度至少10mm，当铸锭直径大于300mm时，铜制内套的侧壁厚度至少12mm。
上述方法中，当金属熔体为铜或铜合金时，二冷水喷孔的孔径1～3.5mm；当金属熔体为铝、镁、铝合金或镁合金时，二冷水喷孔的孔径0.5～2.5mm。
上述方法中，对两组励磁线圈分别通入交变电流或脉冲电流时，电流强度50～200A，频率10～30Hz；其中当通入脉冲电流时，占空比10～30％。
本发明的装置及方法对于圆锭或扁锭均有很强的适用性。
本发明的装置及方法对于钢铁的电磁半连续铸造同样适用。
本发明的主要技术原理为：针对传统电磁连铸过程中单一线圈所产生的磁场作用区域小的缺点，将励磁线圈分为两组并通以相位差为90°的差相电流，通过调节线圈的高度及各线圈间的轴向距离，显著提高磁场在金属熔体中的强度与作用区域，提高电磁利用率；针对传统铜制内套厚度较大，使得磁场在内套中的损耗较大致使作用与熔体中的磁场强度减小的缺点，将内套的厚度减小，并针对不同的铸造合金施加不同形式及分布的加强筋以增加内套的强度；通过上述方式能够显著增大作用于熔体的磁场强度与作用区域，生产出细晶、均匀，表面质量好的铸锭。
发明的有益效果
有益效果
本发明通过以上技术特点，可以实现以下积极效果：
(1)铜制内套厚度较传统内套小，显著提高了透磁性，提高了电磁利用率，对于铜合金、铝合金、镁合金、钢铁等金属的半连铸造均可产生积极作用；
(2)对不同尺寸、规格与种类的铸造合金均有很强的适用性，且可根据合金种类的不同改变内套的厚度并施加以不同分布的加强筋以加强内套的强度；
(3)励磁线圈可根据不同铸造合金的特点，调节线圈的匝数比与长宽比，调节励磁线圈位置，且对线圈所施加的差相电流的参数(电流强度I，频率f)进行调整，所产生的差相磁场可有效的提高电磁利用率并对熔体有很大的渗透率 ，对于金属熔体中磁场的均匀分布具有积极效果；
(4)电磁力作用于金属熔体，不与熔体直接接触，不引入其他杂质且不污染金属熔体；
(5)装置结构紧凑，安全性高，装配简单且易于维护。
对附图的简要说明
附图说明
图1为本发明实施例1中的有色金属及其合金电磁半连铸装置剖面结构示意图；图中，1、结晶器上盖板，2、结晶器外壳，3、冷却水入口，4、固定螺栓，5、线圈压板，6、线圈支撑块，7、结晶器封水板，8、励磁线圈，9、紧固螺栓，10、密封圈，11、铜制内套，12、二冷水喷孔，13、圆环体，14、弧形体，15、长柱状体，16、短柱状体；
图2为本发明实施例中的铜制内套结构示意图；图中，(a)加强筋由多个圆环体组成；(b)加强筋由多个排弧形体组成，每排弧形体有若干单个弧形体，各排弧形体在垂直方向上交错排列；(c)加强筋由多个圆环体和多个柱状体构成网格状，柱状体为长柱状体；(d)加强筋由多个圆环体和多个柱状体构成网格状，柱状体为短柱状体；
图3为本发明实施例中的加强筋截面结构示意图；图中，(a)垂直截面为矩形；(b)垂直截面为梯形；(c)垂直截面为半圆形；
图4为本发明实施例中励磁线圈排布方式示意图；其中：(a)为两组励磁线圈按顺序排布；(b)为两组组励磁线圈交替排布；
图5为本发明实施例1中不同励磁线圈长宽比时金属熔体中的磁感应强度分布云图；图中，(a)励磁线圈长宽比为4∶1；(b)励磁线圈长宽比为2∶1；(c)励磁线圈长宽比为1∶1；(d)励磁线圈长宽比为1∶2；(e)励磁线圈长宽比为1∶4；
图6为本发明实施例1中两组线圈中通入相同相位的脉冲电流后一周期内的洛伦兹力分布云图；图中，T为周期；(a)0.2T，(b)0.4T，(c)0.6T，(d)0.8T，(e)1T；
图7为本发明实施例1中两组线圈中通入相位差为90°的脉冲电流后一周期内的洛伦兹力分布云图；图中，T为周期；(a)0.2T，(b)0.4T，(c)0.6T，(d )0.8T，(e)1T；
图8为本发明实施例中二冷水喷孔间距设置方式示意图；图中，d为二冷水喷孔直径，L为相邻两个二冷水喷孔间距；
图9为本发明实施例3中和传统DC铸造对比试验制备的Φ300mm纯铜铸锭的宏观组织图；图中，(a)传统DC铸造；(b)本发明实施例3；
图10为本发明实施例3中和传统DC铸造对比试验制备的Φ300mm纯铜铸锭的外观照片图；图中，(a)传统DC铸造；(b)本发明实施例3；
图11为本发明实施例2中和传统DC铸造对比试验制备的AZ31镁合金的宏观组织图；图中，(a)传统DC铸造；(b)本发明实施例2；
图12为本发明实施例2中和传统DC铸造对比试验制备的AZ31镁合金半径方向主元素宏观偏析曲线图；图中，(a)传统DC铸造；(b)本发明实施例2。
发明实施例
本发明的实施方式
本发明实施例中采用的铜制内套由上法兰和侧壁组成，上法兰与侧壁为一体式结构。
本发明实施例中铜制内套的侧壁厚度为6～20mm。
本发明实施例中，加强筋的垂直截面为矩形、侧放的梯形或侧放的半圆形；结构如图3所示；当垂直截面为矩形时，沿铜制内套向外的横向厚度3～9mm，高度6～20mm；当垂直截面为侧放的梯形时，梯形的上边长3～10mm，下边长6～20mm，高度3～9mm；当垂直截面为半圆形时，半圆形的直径6～20mm。
本发明实施例中，铜制内套的内侧壁上设有镀层，镀层为铬镀层、Ni-Fe镀层、Ni-Co合金镀层、Ni-Fe-W-Co合金镀层或Ni-P合金镀层。
本发明实施例中，结晶器外壳的材质为钢，上盖板和结晶器封水板的材质为顺磁性不锈钢，顺磁性不锈钢选用304不锈钢、321不锈钢或347不锈钢。
本发明实施例中，当加强筋由多个圆环体13组成时，相邻两个圆环体13的垂直间距15～50mm；当加强筋由多排弧形体14组成时，相邻两排弧形体14的垂直间距15～50mm，每排弧形体14中相邻两个弧形体14的水平间距5～25mm；当加强筋由多个圆环体13和多个柱状体构成网格状时，相邻两个圆环体的垂直间距15～50 mm，所述的柱状体分为长柱状体15和短柱状体16，长柱状体15的两端分别与最上方的圆环体和最下方的圆环体13连接，短柱状体16的两端分别与相邻的两个圆环体13连接；结构如图2所示。
本发明实施例中，铜制内套的内部空间的垂直截面为等腰梯形或倒置的等腰梯形，等腰梯形或倒置的等腰梯形的侧边与轴线的夹角θ＝1°～8°；当铸造合金为铜或铜合金时，垂直截面为倒置的等腰梯形；当铸造合金为铝、镁、铝合金或镁合金时，垂直截面为等腰梯形。
本发明实施例中的两组励磁线圈中，其中一组励磁线圈的长宽比为1∶N，则另一组励磁线圈的长宽比为N∶1，其中N＝1～5；励磁线圈的匝数30～150，相邻两个励磁线圈的间距10～50mm，两组励磁线圈的匝数比为1∶N，其中N＝0.2～5；两组励磁线圈中的各个励磁线圈单体从上到下排列，且以结晶器轴线为轴。
本发明实施例中，两组励磁线圈中的每个线圈同向排布，即通入每个线圈中的交流电流的流向相同，保证每个线圈所产生的磁场的磁力线相同。
本发明实施例中，当每组励磁线圈中的励磁线圈数量超过1个时，按每组励磁线圈上下排布，如图4(a)所示；或者每组励磁线圈中的单个励磁线圈交替排布，如图4(b)所示。
本发明实施例中，当金属熔体为铜或铜合金时，上法兰厚度10～20mm；当金属熔体为铝、镁、铝合金或镁合金时，上法兰厚度6～15mm。
本发明的有色金属及其合金电磁半连铸装置中，当制备的铸锭直径小于200mm时，铜制内套不设置加强筋。
本发明实施例中的励磁线圈采用的电磁线为市购的双层聚酰亚胺-氟46复合薄膜包扁铜线。
本发明实施例中，各励磁线圈单体中，最下方的励磁线圈单体的水平高度高于结晶器中金属熔体的液穴中心的高度。
本发明实施例中，结晶器内部没有金属熔体时，励磁线圈产生磁场时，铜制内套内部的磁感应强度20～200mT。
本发明实施例中，二冷水喷孔截面为圆形；当金属熔体为铜或铜合金时，二冷水喷孔的孔径1～3.5mm；当金属熔体为铝、镁、铝合金或镁合金时，二冷水喷孔 的孔径0.5～2.5mm；当金属熔体为铜或铜合金时，相邻两个二冷水喷孔的间距为二冷水喷孔直径的3～5倍；当金属熔体为铝、镁、铝合金或镁合金时，相邻两个二冷水喷孔的间距为二冷水喷孔直径的2～4倍；结构如图8所示。
本发明实施例中，当金属熔体为铜或铜合金时，铜制内套的侧壁厚度为8～20m m。
本发明实施例中，当铸锭直径小于150mm时，铜制内套的侧壁厚度至少8mm，当铸锭直径在150～300mm之间，铜制内套的侧壁厚度至少10mm，当铸锭直径大于300mm时，铜制内套的侧壁厚度至少12mm。
本发明实施例中，当金属熔体为铜或铜合金时，二冷水喷孔的孔径1～3.5mm；当金属熔体为铝、镁、铝合金或镁合金时，二冷水喷孔的孔径0.5～2.5mm。
本发明实施例中，对两组励磁线圈分别通入交流电流时，电流强度50～200A，频率10～30Hz。
本发明实施例中，上盖板与封水板的材质选用顺磁性不锈钢，以便两组励磁线圈产生的差相磁场能够顺利通过且磁力线不发生变形，结晶器外壳的材质为普通钢，让磁场从结晶器外壳中不易通过，减小磁场在外界的损失。
本发明实施例中，由于铜制内套侧壁厚度较薄，考虑到在半连续铸造过程中铜制内套存在巨大温度梯度会发生热变形等问题，故在铜制内套外表面施加不同截面形状与不同形式的加强筋以加强内套的强度。
本发明实施例中，所用的电流为差相电流，差相电流分别通入两组励磁线圈中，产生差相磁场作用于金属熔体；一组励磁线圈中通入初相位为0°的电流，另一组线圈中通入初相位为90°的电流；在各个励磁线圈之间的轴向间距通过线圈支撑块的高度来调节。
实施例1
有色金属及其合金电磁半连铸装置包括结晶器和励磁线圈系统；结构如图1所示，结晶器由上盖板1、结晶器外壳2、铜制内套11和结晶器封水板7组成，结晶器外壳2上部设有冷却水入口3，铜制内套11底部设有二冷水喷孔12；
铜制内套11的内部空间的垂直截面为倒置的等腰梯形；
结晶器上盖板1的上方通过螺栓与铜制内套11的上法兰固定，并通过密封圈10 密封连接；
结晶器外壳2上部通过紧固螺栓9与结晶器上盖板1固定连接；结晶器外壳2底部通过紧固螺栓9与结晶器封水板7固定连接；
结晶器封水板7为环形，通过紧固螺栓9与结晶器外壳2固定在一起，并通过密封圈10密封连接；
励磁线圈系统固定在结晶器外壳2和铜制内套11之间的冷却水槽内，由固定螺栓4、线圈压板5、线圈支撑块6和励磁线圈8组成；
固定螺栓4焊接固定在结晶器外壳2的底部；若干个线圈压板5固定在固定螺栓4上；每个励磁线圈8和每个线圈支撑块6上下交替排列，并且相邻两个线圈压板5之间只有一个线圈支撑块6；通过固定螺栓4、线圈压板5和结晶器外壳2底部将线圈支撑块6和励磁线圈8压紧固定；
铜制内套11的外侧壁上设有加强筋13，加强筋13与铜制内套11的侧壁为一体结构，加强筋13由多个圆环体组成，结构如图2(a)所示；
励磁线圈8分为两组，两组励磁线圈中的每组励磁线圈串联，且各自与电源连接；
采用上述装置，对不同线圈长宽比(4∶1，2∶1，1∶1，1∶2，1∶4)下的镁合金熔体中的磁场分布进行了数值模拟，结晶器水槽中固定的励磁线圈为两组，线圈匝数为40匝，每组各一个，两组线圈位于镁合金熔体高度的中心处且两组线圈之间的间距为10mm，上部的励磁线圈通入初相位为0°的脉冲电流，下部的线圈通入初相位为90°的脉冲电流，所通入脉冲电流的电磁参数设为电流强度I＝80A，频率f＝20Hz，占空比D＝20％；数值模拟的结果如图5所示；模拟结果表明，改变线圈的长宽比可以有效改变熔体中磁感应强度的大小及分布；线圈长宽比越小，熔体中磁感应强度的大小有所减小，但在熔体中的分布区域增加且分布的均匀性较好；
对两组线圈中分别通入相同相位的脉冲电流与相位差为90°的脉冲电流；两种情况下的金属熔体中的洛伦兹力分布进行数值模拟，一周期内洛伦兹力分布云图如图6与图7所示；两组线圈的线圈匝数分别为40匝，每组线圈各一个，线圈之间的轴向距离为30mm，相位差为90°时，上部的励磁线圈通入初相位为0°的脉 冲电流，下部的线圈通入初相位为90°的脉冲电流，所通入脉冲电流的电磁参数设为电流强度I＝80A，频率f＝20Hz，占空比D＝20％；模拟结果表明，通入单向的脉冲电流与差相的脉冲电流的情况下，熔体中的洛伦兹力大小没有太大变化，但在差相磁场的作用下，洛伦兹力最大值会在熔体中两组线圈中心平面位置交替变化，会使熔体中的流场、温度场及溶质场相对单向磁场作用下分布更加均匀，显著提高金属铸锭的冶金质量；故相同电磁参数下差相磁场相比单向磁场对于金属熔体的搅拌作用更好。
实施例2
装置结构同实施例1，不同点在于：两个线圈的轴向间距为20～40mm，铜制内套的内部空间的垂直截面为等腰梯形，且直径为320mm，厚度为8mm，不设置加强筋，励磁线圈中通入的电流为谐波电流；
采用上述装置对
Figure PCTCN2019102802-appb-000001
的AZ31镁合金进行结晶器连铸，先向冷却水槽内通入冷却水，冷却水从二冷水喷孔喷出；将金属熔体导入结晶器内，使金属熔体的液面达到预定高度；所述的金属熔体为有色金属或有色金属合金；
通过电源对两组励磁线圈分别通入不同初相位的谐波电流，使每组励磁线圈各自产生一组电磁信号，各自形成谐波磁场；两组励磁线圈通入的交流电流的相位差为90°，形成的差相谐波磁场作用于结晶器内的金属熔体；
启动有色金属及其合金电磁半连铸装置，进行铸造，铸造温度为720℃，铸造速度为1.12mm/s，冷却水量为10.5～12.5m 3/h，差相电流的强度为50～80A，频率10～30Hz，通过二冷水喷孔喷出的二冷水对结晶器下方的铸锭冷却，直至铸造完成；
采用传统DC铸造制备相同镁合金进行对比试验；宏观组织如图11所示，由图可见，传统DC铸造的铸锭柱状晶粗大，而上述方法所获得的铸锭晶粒细小且均匀分布；铸锭半径方向上主元素宏观偏析对比如图12所示，由图可见，上述方法所铸造出的铸锭元素宏观偏析较传统DC铸造更小，分布更均匀。
实施例3
装置结构同实施例1，不同点在于：
(1)加强筋由5排弧形体组成，如图2(b)所示；
(2)每组励磁线圈由两个励磁线圈组成，排布方式如图4(a)所示；相邻的励磁线圈的轴向距离为30～50mm，
(3)铜制内套的内部空间的垂直截面为倒置的等腰梯形，侧壁厚度10mm；
采用上述装置制备纯铜铸锭，
Figure PCTCN2019102802-appb-000002
铸造温度为1180℃，铸造速度为4m/h，冷却水压为34～38m 3/h，结晶器中固定的励磁线圈为两组，电流强度200A，频率20Hz，占空比20％；
采用传统DC铸造制备相同纯铜铸锭进行对比试验；宏观组织照片如图9所示；由图可见，本实施例的方法获得的铸锭柱状晶更小，细小的等轴晶区域明显增加；外观照片如图10所示，由图可见，采用传统DC铸造所获得的铸锭表面有明显的褶皱等缺陷，而本实施例所获得的铸锭的表面更光滑，表面质量更好。

Claims (6)

  1. 一种有色金属及其合金电磁半连铸装置，其特征在于包括结晶器和励磁线圈系统；结晶器由上盖板、结晶器外壳、铜制内套和结晶器封水板组成，结晶器外壳上部设有冷却水入口，铜制内套底部设有二冷水喷孔；励磁线圈系统固定在结晶器外壳和铜制内套之间的冷却水槽内，由固定螺栓、线圈压板、线圈支撑块和励磁线圈组成；其中铜制内套的外侧壁上设有或不设有加强筋，当设有加强筋时，加强筋与铜制内套为一体结构，加强筋由多个圆环体组成，或者由多排弧形体组成，或者由多个圆环体和多个柱状体构成网格状；所述的铜制内套的侧壁厚度为6～20mm；所述的励磁线圈分为两组，两组励磁线圈中的每组励磁线圈串联，且各自与电源连接。
  2. 根据权利要求1所述的一种有色金属及其合金电磁半连铸装置，其特征在于所述的加强筋的垂直截面为矩形、侧放的梯形或侧放的半圆形；当垂直截面为矩形时，沿铜制内套向外的横向厚度3～9mm，高度6～20mm；当垂直截面为侧放的梯形时，梯形的上边长3～10mm，下边长6～20mm，高度3～9mm；当垂直截面为半圆形时，半圆形的直径6～20mm。
  3. 根据权利要求1所述的一种有色金属及其合金电磁半连铸装置，其特征在于所述的铜制内套的内部空间的垂直截面为等腰梯形或倒置的等腰梯形，等腰梯形的侧边或倒置的等腰梯形的侧边与轴线的夹角θ＝1°～8°。
  4. 根据权利要求1所述的一种有色金属及其合金电磁半连铸装置，其特征在于当加强筋由多个圆环体组成时，相邻两个圆环体的垂直间距15～50mm；当加强筋由多排弧形体组成时，相邻两排弧形体的垂直间距15～50mm，每排弧形体中相邻两个弧形体的水平间距5～25mm；当加强筋由多个圆环体和多个柱状体构成网格状时，相邻两个圆环体的垂直间距15～50mm，所述的柱状体分为长柱状体 和短柱状体，长柱状体的两端分别与最上方的圆环体和最下方的圆环体连接，短柱状体的两端分别与相邻的两个圆环体连接。
  5. 根据权利要求1所述的一种有色金属及其合金电磁半连铸装置，其特征在于所述的两组励磁线圈中，两组励磁线圈的长宽比同时设为1∶N，或其中一组励磁线圈的长宽比为1∶N，则另一组励磁线圈的长宽比为N∶1，其中N＝1～5。
  6. 根据权利要求1所述的一种有色金属及其合金电磁半连铸装置，其特征在于所述的励磁线圈的匝数30～150，相邻两个励磁线圈的间距10～50mm；两组励磁线圈的匝数比为1∶N，其中N＝0.2～5；两组励磁线圈中的各个励磁线圈单体从上到下排列，且以结晶器轴线为轴。
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000176609A (ja) * 1998-12-18 2000-06-27 Daido Steel Co Ltd 連続鋳造に使用する鋳型
CN202192235U (zh) * 2011-08-17 2012-04-18 中国科学院金属研究所 镁合金低频脉冲磁场辅助半连续铸造结晶器
CN106925736A (zh) * 2017-04-01 2017-07-07 东北大学 一种半连续铸造液穴熔体的电磁处理装置及其工作方法
CN106944598A (zh) * 2017-04-01 2017-07-14 东北大学 一种电磁半连续铸造装置及其铸造方法
CN108465792A (zh) * 2018-03-29 2018-08-31 东北大学 一种差相位脉冲磁场电磁连铸方法
CN110125358A (zh) * 2019-05-29 2019-08-16 东北大学 一种有色金属及其合金电磁半连铸装置

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62227561A (ja) * 1986-03-27 1987-10-06 Kobe Steel Ltd 鋳型内縦かく拌用電磁かく拌装置
JPH11170016A (ja) * 1997-12-08 1999-06-29 Nippon Steel Corp 溶融金属の流動制御装置
CN201720405U (zh) * 2010-06-24 2011-01-26 中铝洛阳铜业有限公司 一种铸造铜及铜合金圆锭用结晶器
CN202291315U (zh) * 2011-10-26 2012-07-04 宝山钢铁股份有限公司 一种固定水缝式连铸结晶器
CN102554153A (zh) * 2012-01-06 2012-07-11 中冶连铸技术工程股份有限公司 分体式带导流水槽的水套及组装方法
CN108339963B (zh) * 2018-03-29 2019-07-30 东北大学 一种差相位行波磁场电磁铸造方法
CN108856681B (zh) * 2018-09-26 2020-12-18 东北大学 一种镁合金熔体处理方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2000176609A (ja) * 1998-12-18 2000-06-27 Daido Steel Co Ltd 連続鋳造に使用する鋳型
CN202192235U (zh) * 2011-08-17 2012-04-18 中国科学院金属研究所 镁合金低频脉冲磁场辅助半连续铸造结晶器
CN106925736A (zh) * 2017-04-01 2017-07-07 东北大学 一种半连续铸造液穴熔体的电磁处理装置及其工作方法
CN106944598A (zh) * 2017-04-01 2017-07-14 东北大学 一种电磁半连续铸造装置及其铸造方法
CN108465792A (zh) * 2018-03-29 2018-08-31 东北大学 一种差相位脉冲磁场电磁连铸方法
CN110125358A (zh) * 2019-05-29 2019-08-16 东北大学 一种有色金属及其合金电磁半连铸装置

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