Rotating cooling roller

Abstract

The present invention discloses a rotating cooling roller, a vacuum quenching device and a method for preparing an amorphous strip, which belongs to the field of rapid solidification technology and solves the problem of insufficient cooling strength of the existing cooling roller. The rotating cooling roller includes a rotating shaft, a flange, a cooling jacket, a core barrel and a rolling bearing; the cooling jacket is a cylinder without end faces and hollow inside, and the two ends of the cooling jacket are respectively connected to a flange, and the other ends of the two flanges are respectively connected to the rotating shaft; the rotating shaft is hollow inside for the cooling medium to flow through; the two flanges and the cooling jacket form a spindle-shaped internal space, and the core barrel is arranged in the spindle-shaped internal space, and a gap is left between the flange and the cooling jacket respectively, so that the cooling medium from the rotating shaft can flow through; the shape of the core barrel corresponds to the spindle-shaped internal space, and its two ends are respectively connected to the rotating shaft, and rolling bearings are arranged at the connection.

Description

Technical Field

[0001] The invention relates to the technical field of rapid solidification, and in particular to a rotary cooling roller, vacuum rapid quenching equipment and a method for preparing an amorphous strip. Background Art

[0002] Vacuum rapid quenching technology (vacuum single roller spinning) is the main technical means for batch preparation of amorphous alloy foil strips (thickness 10-50μm). Due to the special state of vacuum, the alloy melt can only rely on heat conduction with the cooling roller to solidify into amorphous foil strips. In order to achieve a cooling speed of 10 4 ~10 9 K / s, which requires the cooling roller to provide sufficient cooling intensity.

[0003] The internal water channel design of the cooling roller is the main means to improve the cooling intensity. The applicant has made relevant elaborations in the patent (ZL201621099453.5) and has achieved certain results in actual use, but the cooling intensity needs to be further improved. Summary of the invention

[0004] In view of the above situation, the present invention aims to provide a rotating cooling roller, a vacuum quenching equipment and a method for preparing an amorphous strip, so as to solve at least one of the problems of insufficient cooling strength of the existing cooling roller and the resulting low yield of amorphous strip and difficulty in completely amorphizing the prepared strip.

[0005] The purpose of the present invention is mainly achieved through the following technical solutions:

[0006] In a first aspect, the present invention provides a rotating cooling roller, the rotating cooling roller comprising a rotating shaft, a flange, a cooling jacket, a core barrel and a rolling bearing;

[0007] The cooling jacket is a hollow cylinder without end faces, and the two ends of the cooling jacket are respectively connected to a flange, and the other ends of the two flanges are respectively connected to the rotating shaft; the rotating shaft is hollow inside to allow the cooling medium to flow through;

[0008] The two flanges and the cooling jacket form a spindle-shaped internal space, the core barrel is arranged in the spindle-shaped internal space, and a gap is left between the flanges and the cooling jacket respectively, so that the cooling medium from the rotating shaft can flow through;

[0009] The outer shape of the core barrel corresponds to the spindle-shaped internal space, and both ends of the core barrel are respectively connected to the rotating shaft, and rolling bearings are provided at the connection points.

[0010] Optionally, the flange has a conical structure.

[0011] Optionally, the end of the flange with a larger diameter is connected to the cooling jacket, and the end of the flange with a smaller diameter is connected to the rotating shaft.

[0012] Optionally, a guide groove is provided on the inner wall of the flange.

[0013] Optionally, the gap between the core barrel and the cooling jacket is 5 to 10 mm on one side.

[0014] Optionally, the cooling jacket is made of a material with high thermal conductivity.

[0015] Optionally, the inner wall of the cooling jacket is provided with single-path or multi-path spiral grooves.

[0016] Optionally, the cross-section of the spiral groove is semi-elliptical, semi-circular, triangular, rectangular or trapezoidal.

[0017] Optionally, the interior of the rotating shaft is hollow to allow cooling medium to flow through; the rotating shaft includes two sections, one section is used for the inflow of cooling medium, and the other section is used for the outflow of cooling medium; each section of the rotating shaft is connected to the end of the flange with a smaller diameter.

[0018] Optionally, each rotating shaft section has an open end and a closed end.

[0019] Optionally, a through hole communicating with the outside is provided on the side wall of each section of the rotating shaft, and the through hole is provided in the gap between the flange and the core barrel to enable the cooling medium to flow in or out of the rotating shaft and the internal flow path.

[0020] Optionally, there are multiple through holes, and the multiple through holes are evenly arranged along the circumference of the rotating shaft.

[0021] Optionally, a locking member is further included, and the locking member is arranged at the connection between the core barrel and the rotating shaft to fix the core barrel and the rotating shaft.

[0022] Optionally, the locking member includes a buckle.

[0023] Optionally, the core barrel has a hollow structure.

[0024] In a second aspect, the present invention further provides a vacuum quenching device, which includes a quenching vacuum chamber, in which the above-mentioned rotating cooling roller is arranged.

[0025] In a third aspect, the present invention further provides a method for preparing an amorphous strip, which is prepared by using the above-mentioned vacuum rapid quenching equipment, comprising the following steps:

[0026] Step 1: Load the brazing master alloy into the melting crucible of the vacuum quenching equipment, evacuate the vacuum, and then fill the vacuum quenching equipment with inert gas;

[0027] Step 2: Start the melting furnace to melt the brazing master alloy until the brazing master alloy is completely melted;

[0028] Step 3: Transfer the melted brazing master alloy to a tundish and let it stand;

[0029] Step 4: Start the rotating cooling roller, pressurize the tundish and spray the belt, and maintain the pressure difference between the tundish and the chamber.

[0030] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0031] a) The flange of the present invention has a conical structure, which forms a spindle-shaped internal space after being connected to a cooling jacket without end faces and having a hollow interior. The core barrel is a spindle-shaped sealed cavity structure, which corresponds to the spindle-shaped internal space formed by the flange and the cooling roller, and has a gap between the flange and the cooling jacket, respectively, so as to construct an internal flow path of a spindle-shaped streamlined structure. The streamlined structural design is conducive to overcoming the centrifugal force, and can reduce the influence of the centrifugal force of the high-speed rotation of the cooling roller on the poor internal flow of the cooling medium, especially the cooling medium in the annular waterway between the cooling jacket and the core barrel, thereby facilitating the rapid distribution of the cooling medium through the inlet, and the rapid collection of the cooling medium through the internal flow path to the outlet to flow out, ensuring that the cooling medium can pass quickly. On the one hand, it can take away more heat in a short time, achieving the purpose of efficient heat exchange, thereby improving the cooling intensity; on the other hand, it can increase the cooling uniformity and increase the yield rate of amorphous strip to more than 80% (the yield rate of amorphous strip in the prior art is about 50%).

[0032] b) The present invention connects a rolling bearing at the connecting end of the core barrel and the rotating shaft, so that the core barrel can be in a follow-up state when the rotating shaft and the cooling sleeve rotate, which is equivalent to applying a shear force perpendicular to the direction of the centrifugal force to the internal cooling medium, with the purpose of offsetting a part of the centrifugal force, increasing the axial movement efficiency of the cooling medium, and improving the cooling intensity of the rotating cooling roller.

[0033] c) The present invention fixes the core barrel to the rotating shaft by setting a locking member, so that the core barrel is in a rotating state, that is, the core barrel rotates with the rotating shaft. The cooling intensity of the core barrel in the following state and the rotating state is different (see Table 1), thereby achieving the adjustment of the cooling intensity and expanding the application range of the rotating cooling roller of the present invention.

[0034] d) The present invention can achieve rapid distribution of the cooling medium by arranging the guide groove on the inner wall of the flange, thereby ensuring that the cooling medium can pass quickly and take away more heat in a short time, achieving the purpose of efficient heat exchange, thereby further improving the cooling intensity.

[0035] e) The present invention provides single-channel or multi-channel spiral grooves on the inner wall of the cooling jacket, and increases the cooling capacity of the system by controlling the flow direction of the cooling medium to be opposite to the rotation direction of the cooling roller, thereby improving the cooling intensity.

[0036] f) The cooling roller of the present invention has great promotion and practical value. It is applied to vacuum quenching equipment and can prepare alloy system amorphous foil strips that are urgently needed in the aerospace field and do not have strong amorphous forming ability. After being widely promoted and applied, it will produce good economic and social benefits.

[0037] g) The rotating cooling roller in the vacuum quenching equipment of the present invention constructs an internal flow path with a spindle-shaped streamline structure, which is conducive to overcoming the centrifugal force and can reduce the influence of the centrifugal force of the high-speed rotation of the cooling roller on the poor internal flow of the cooling medium, especially the cooling medium in the annular water path between the cooling jacket and the core barrel, thereby facilitating the rapid distribution of the cooling medium through the inlet and the rapid collection of the cooling medium to the outlet through the internal flow path, thereby ensuring that the cooling medium can pass through quickly. On the one hand, more heat can be taken away in a short time, achieving the purpose of efficient heat exchange, thereby improving the cooling intensity; on the other hand, it can increase the cooling uniformity and increase the yield rate of amorphous strip to more than 80% (the yield rate of amorphous strip in the prior art is about 50%).

[0038] h) The method for preparing the amorphous strip of the present invention adopts a vacuum quenching device with high cooling intensity and good cooling uniformity, which can increase the yield of the amorphous strip to more than 80% (the yield of the amorphous strip in the prior art is about 50%).

[0039] Other features and advantages of the present invention will be described in the following description, and part of them will become obvious from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the contents particularly pointed out in the written description and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The accompanying drawings are only used for the purpose of illustrating specific embodiments and are not to be considered as limiting the present invention. In the entire drawings, the same reference symbols represent the same components;

[0041] Figure 1 This is a schematic diagram of the structure of the rotating cooling roller of the present invention;

[0042] Figure 2-1 This is a flow field velocity cloud diagram (longitudinal section) of the rotating cooling roller core barrel of the present invention;

[0043] Figure 2-2 This is a flow field velocity cloud diagram (longitudinal section) of the rotating cooling roller core barrel of the present invention;

[0044] Figure 3-1It is a flow field velocity vector diagram (longitudinal section) of the rotating cooling roller core barrel of the present invention;

[0045] Figure 3-2 It is the velocity vector diagram of the flow field of the rotating cooling roller core barrel of the present invention (longitudinal section);

[0046] Figure 4 The strip prepared in Example 9 of the present invention;

[0047] Figure 5 The strip prepared in Example 6 of the present invention;

[0048] Figure 6 It is a schematic diagram of the structure of the vacuum rapid quenching equipment of the present invention;

[0049] Figure 7 Strip material prepared for the rotating cooling roller (with core drum following) of the present invention;

[0050] Figure 8 The tensile specimen fracture diagram is a tensile strength test diagram of a brazed joint after the amorphous strip of the present invention is used as a brazing filler metal.

[0051] Reference numerals:

[0052] 1-rotating shaft; 2-flange; 3-cooling copper sleeve; 4-core barrel; 5-rotating dynamic seal; 6-rolling bearing; D-spiral groove width; h-spiral groove height; 7-melting furnace vacuum chamber; 8-smelting device; 9-quick quenching vacuum chamber; 10-vacuum silo; 11-online instant grinding device; 12-rotating cooling roller; 13-turntable tundish system; 14-strip guide cooling roller; 15-strip anti-stacking track. DETAILED DESCRIPTION

[0053] Preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the present invention and are used to explain the principles of the present invention together with the embodiments of the present invention.

[0054] In a first aspect, the present invention provides a rotating cooling roller. Figure 1 As shown, the rotating cooling roller includes a rotating shaft 1, a flange 2, a cooling jacket 3, a core barrel 4, a rotating dynamic seal 5 and a rolling bearing 6.

[0055] The flange 2, the core barrel 4 and the cooling jacket 3 form an internal flow path through which the cooling medium flows. Figure 1 The arrow in the middle indicates the flow direction of the cooling medium.

[0056] The cooling jacket 3 is a hollow cylinder without end faces. The two ends of the cooling jacket are respectively connected to a flange 2, and the other ends of the two flanges 2 are respectively connected to the rotating shaft 1. The two flanges 2 and the cooling jacket 3 form a spindle-shaped internal space. The core barrel 4 is arranged in the internal space formed by the flange 2 and the cooling jacket 3, and a gap is left between the flange 2 and the cooling jacket 3 for the cooling medium to flow through. Specifically, as Figure 1 As shown, the longitudinal section of the structure formed by the flange 2 and the cooling jacket 3 is similar to a hexagon.

[0057] The flange 2 has a conical structure, and the conical angle is 40°-70°, for example, 40°, 50°, 60°, 70°. The inner wall of the flange 2 is provided with a guide groove, which enables the cooling medium (for example, water) to be quickly distributed after entering the cooling roller.

[0058] Specifically, the end of the flange 2 with a larger diameter is connected to the cooling jacket 3 , and the end of the flange 2 with a smaller diameter is connected to the rotating shaft 1 .

[0059] The core barrel 4 has a spindle-shaped sealed cavity structure, and its outer shape corresponds to the spindle-shaped internal space. Both ends of the core barrel 4 are respectively connected to the rotating shaft 1. A rolling bearing 6 is fixedly connected to the connection between the core barrel 4 and the rotating shaft 1, which can keep the core barrel 4 in a follow-up state (water flow) when the rotating shaft 1 and the cooling jacket 3 rotate.

[0060] The flange 2, the core barrel 4 and the cooling jacket 3 form an internal flow path with a spindle-shaped streamlined structure. The streamlined structural design is conducive to overcoming the centrifugal force, and can reduce the influence of the centrifugal force of the high-speed rotation of the cooling roller on the cooling medium, especially the cooling medium in the annular water path between the cooling jacket and the core barrel, thereby facilitating the rapid distribution of the cooling medium through the inlet and the rapid collection of the cooling medium through the internal flow path to the outlet, thereby improving the cooling intensity.

[0061] In a preferred embodiment, the longitudinal section of the core barrel 4 is similar to a hexagon.

[0062] In another embodiment, the rotary cooling roller further includes a locking member (e.g., a buckle), which is disposed at the connection between the core barrel 4 and the rotating shaft 1 to fix the core barrel 4 to the rotating shaft 1, and the core barrel 4 is in a rotating state, that is, the core barrel 4 rotates with the rotating shaft 1. The present invention can realize the switching between the core barrel 4 in the following state and the rotating state by arranging the locking member, and the cooling intensity of the core barrel 4 in the following state and the rotating state is different (see Table 1), thereby realizing the adjustment of the cooling intensity and expanding the application range of the rotary cooling roller of the present invention.

[0063] Specifically, the interior of the rotating shaft 1 is hollow for the cooling medium to flow through. The rotating shaft 1 includes two sections, one for the inflow of the cooling medium and the other for the outflow of the cooling medium. Each section of the rotating shaft is connected to the end with a smaller diameter of the flange 2. The rotating shaft 1 is open at one end and closed at the other end. A through hole connected to the outside is provided on the side wall of each section of the rotating shaft. The through hole is provided at the gap left between the flange 2 and the core barrel 4 to enable the cooling medium to flow in or out of the rotating shaft and the internal flow path, that is, to enable the cooling medium in the rotating shaft 1 to flow into the internal flow path or to enable the cooling medium in the internal flow path to flow into the rotating shaft 1, so that the cooling medium is collected at the outlet and flows out after flowing through the internal flow path.

[0064] Specifically, there are multiple through holes, and the multiple through holes are evenly distributed along the circumference of the rotating shaft 1 .

[0065] In a preferred embodiment, a rotary dynamic seal 5 is further provided at the connection between the core barrel and the rotating shaft to prevent the cooling medium in the internal flow path from flowing into the cavity of the core barrel 4 .

[0066] It should be noted that, compared with a solid structure, the core barrel 4 designed as a hollow structure is beneficial to reducing the weight of the cooling roller, saving raw materials and reducing costs.

[0067] The inner wall of the cooling jacket 3 is provided with a single or multiple spiral grooves to form a spiral water channel. Preferably, it is a multiple spiral groove, for example, 3-5 mutually parallel spiral grooves. When in use, the present invention increases the cooling capacity of the system by controlling the flow direction of the cooling medium to be opposite to the rotation direction of the cooling roller.

[0068] Specifically, the pitch S of the spiral groove is 50-100mm. The cross section of the spiral groove is semi-elliptical, semi-circular, triangular, rectangular or trapezoidal. When the cross section of the spiral groove is semi-elliptical or rectangular, the ratio of width to height is 2-3.5. The present invention can reduce the relatively static area (dead zone) between the cooling medium and the inner surface of the cooling roller formed by high-speed rotation when the cooling medium flows in the spiral waterway by arranging the spiral groove on the inner wall of the cooling sleeve 3; and the existence of the dead zone causes the cooling medium water to contact and vaporize on the inner surface of the cooling roller to form an air film, which hinders heat transfer and is prone to danger in severe cases (excessive steam pressure). The present invention can improve the cooling intensity on the one hand and improve production safety on the other hand by arranging the spiral groove on the inner wall of the cooling sleeve 3.

[0069] The cooling jacket 3 is made of copper, copper alloy or other materials with high thermal conductivity. The gap between the cooling jacket 3 and the core barrel 4 is 5-10 mm on one side, for example, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm. The gap between the flange 2 and the core barrel 4 is 30-40 mm on one side, for example, 30 mm, 32 mm, 35 mm, 37 mm, 39 mm, 40 mm.

[0070] In a second aspect, the present invention provides a vacuum quenching device, such as Figure 6 As shown, it includes a melting furnace vacuum chamber 7, a rapid quenching vacuum chamber 9, and a vacuum silo 10 which are arranged in sequence; the melting furnace vacuum chamber 7, the rapid quenching vacuum chamber 9 and the vacuum silo are independent closed structures, and can be connected to the atmospheric environment without affecting each other and perform corresponding operations respectively.

[0071] A smelting device 8 is provided in the vacuum chamber 7 of the melting furnace, and a smelting crucible for placing the master alloy is provided in the smelting device 8 .

[0072] The above-mentioned rotating cooling roller 12, turntable type tundish system 13, strip guide cooling roller 14 and strip anti-stacking track 15 are arranged in sequence in the rapid quenching vacuum chamber 9.

[0073] In a specific embodiment, the smelting device 8 is a medium frequency melting furnace. The capacity of the medium frequency melting furnace is 10-300 kg, preferably 50-150 kg.

[0074] The turntable tundish system 13 is provided with 3-5 rotatable independent tundishes, each of which can be driven by a horizontal disc to rotate and / or stop along the circumference of the disc. The rotating cooling roller 12 is provided below the tundish, and a nozzle is provided below each tundish to spray cooling medium onto the rotating cooling roller 12. Exemplarily, the capacity of the tundish is 25-100 kg.

[0075] In a preferred embodiment, the vacuum quenching equipment also includes an online instant grinding device 11, which is arranged toward the working surface of the rotating cooling roller 12 and can trim and polish the surface of the rotating cooling roller 12 when the smelting device 8 is feeding and melting.

[0076] The strip guide cooling roller 14 is a two-roller adjustable slit structure, which is arranged at the exit end of the strip leaving the rotating cooling roller 12, controls the flight state of the strip after leaving the roller, guides the strip through the slit into the strip anti-stacking track 15, and performs secondary cooling on the strip.

[0077] In a third aspect, the present invention further provides a method for preparing an amorphous strip, which is prepared by using the above-mentioned vacuum rapid quenching equipment, comprising the following steps:

[0078] Step 1: Load an appropriate amount of solder master alloy into the melting crucible of the vacuum quenching equipment, evacuate the vacuum quenching equipment, and then fill the vacuum quenching equipment with inert gas;

[0079] Step 2: Start the medium frequency induction melting furnace to melt the brazing master alloy until the brazing master alloy is completely melted;

[0080] Step 3: Transfer the melted brazing master alloy to the tundish, keep the tundish in a sealed state, and let it stand;

[0081] Step 4: Start the rotating cooling roller, pressurize the tundish and spray the belt, and maintain a certain pressure difference between the tundish and the rapid quenching vacuum chamber;

[0082] Step 5: Observe the spraying condition of the strip through the window of the vacuum quenching equipment, and adjust the roller speed according to the strip condition until the vacuum quenching process is completed.

[0083] Preferably, in step 1, the vacuum degree is ≤4×10 -2 Pa, for example, 1×10 -2 Pa, 2×10 -2 Pa, 3×10 -2 Pa, 4×10 -2 Pa.

[0084] Preferably, in step 1, the pressure in the vacuum quenching equipment after filling with inert gas is 20-30 kPa, for example, 20 kPa, 22 kPa, 24 kPa, 25 kPa, 27 kPa, 28 kPa, 30 kPa.

[0085] Preferably, in step 2, the melting temperature is 1000-1400°C, for example, 1000°C, 1050°C, 1100°C, 1150°C, 1200°C, 1250°C, 1300°C, 1350°C, 1400°C, preferably 1100-1300°C.

[0086] Preferably, in step 3, the standing time is 2-10 minutes, for example, 2 minutes, 3 minutes, 4 minutes, 5 minutes, 7 minutes, 8 minutes, 9 minutes, 10 minutes.

[0087] Preferably, in step 4, the spray belt pressure is 40-60 kPa, for example, 40 kPa, 45 kPa, 50 kPa, 55 kPa, 60 kPa.

[0088] Preferably, in step 4, the pressure in the tundish is 20-30 kPa greater than the pressure in the rapid quenching vacuum chamber, for example, 20 kPa, 22 kPa, 25 kPa, 27 kPa, 30 kPa.

[0089] Preferably, in step 5, the roller speed is 15-40 m / s, for example 15 m / s, 20 m / s, 25 m / s, 30 m / s, 35 m / s, 40 m / s.

[0090] Specifically, the composition of the amorphous strip may be TiZrCuNiNb.

[0091] Preferably, the composition of the amorphous strip includes, by mass percentage: Zr, 5%-30%, Cu, 10%-15%, Ni, 10%-15%, Nb, 0.5%-3.5%, rare earth elements, 0.1%-0.3%; the remainder is Ti and inevitable trace impurities.

[0092] Preferably, the rare earth element of the present invention is one or more of La, Ce and Y.

[0093] The following is a detailed description of the effects and dosage of the components in the present invention:

[0094] Zr: The addition of Zr can improve the fluidity of the solder and the wettability during the brazing process, thereby facilitating the formation of a uniform brazing joint. Therefore, the present invention limits the Zr content to 5%-30%.

[0095] Cu: The Cu element in the solder lowers the melting point and increases fluidity, which helps the solder to better fill the joint gap and is also beneficial to the diffusion of the element and the phase change. Therefore, the present invention limits the Cu content to 10% to 15%.

[0096] Ni: The addition of Ni element can further improve the corrosion resistance and mechanical properties of the solder, and enhance the durability and service life of the brazing joint. Therefore, the present invention limits the Ni content to 10% to 15%.

[0097] Nb: The addition of an appropriate amount of Nb element can effectively improve the mechanical properties and corrosion resistance of the amorphous alloy, while excessive Nb element may lead to a decrease in performance. Therefore, the present invention limits the Nb content to 0.5% to 3.5%.

[0098] Rare earth elements: Rare earth elements can be internally oxidized to form high melting point compounds, reduce the oxygen content of the matrix, and improve the high temperature oxidation resistance and mechanical properties of the alloy. In the present invention, the rare earth elements enhance the mechanical properties of the titanium alloy in the form of solid solution and intermetallic compounds. Therefore, the present invention limits the rare earth element content to 0.1% to 0.3%.

[0099] Ti: Ti element is the remainder, and its content is >50%.

[0100] The amorphous strip of the present invention is used as a brazing material for welding components made of TA15 titanium alloy at a temperature of 920°C and a vacuum degree of 1×10 -2 Pa and keep warm for 10 minutes. The tensile strength test of the brazed joint showed that the tensile strength of the brazed joint was 930-950 MPa, the elongation after fracture was 11%-15%, and the typical structure of the brazed joint was lamellar structure, which accounted for 75%-90%.

[0101] For the fracture diagram of the tensile specimen, see Figure 8 ,Depend on Figure 8 It can be seen that when the brazing material strip is used for brazing, the corresponding brazing joints are all broken at the substrate after being stretched at room temperature, indicating that the brazing performance is stronger than that of the substrate.

[0102] The microstructure of the amorphous strip (solder) of the present invention includes: Cu and Ni elements diffuse rapidly into the matrix at the brazing interface, Ti element diffuses rapidly into the brazing material, and a diffusion layer is first formed near the matrix on both sides, and gradually widens with the increase of the brazing temperature and the holding time, and then β-Ti nucleates and grows in the liquid brazing material, at which time the remaining liquid phase mainly contains Ti, Zr, Cu, and Ni elements, and solidifies to form a (Ti, Zr) 2 (Cu, Ni) phase. As the temperature decreases, the high-temperature β-Ti gradually undergoes eutectoid decomposition, generating α-Ti distributed in a lamellar form, and the addition of rare earth elements and Nb elements is conducive to the precipitation of lamellar α-Ti, reducing the volume content of the brittle (Ti, Zr) 2 (Cu, Ni) phase, thereby increasing the toughness of the joint.

[0103] The design concept of the amorphous strip (solder) composition of the present invention is as follows: the present invention adds rare earth elements to the titanium-based alloy, forms high-melting-point compounds through internal oxidation of the rare earth elements, reduces the oxygen content of the matrix, and improves the high-temperature oxidation resistance and mechanical properties of the alloy. Rare earth elements enhance the mechanical properties of titanium alloys in the form of solid solution and intermetallic compounds, while improving the strength of the brazed joint (the tensile strength of the brazed joint is 930-950 MPa) and toughness, while reducing the brittleness of the brazed joint (the elongation after fracture is 11%-15%, which is much higher than the elongation after fracture of the prior art <5%), broadening the scope of use of titanium and its alloys, so that they can be used in occasions with high requirements for joint performance.

[0104] Compared with the prior art, the preparation method of the present invention has the following technical effects:

[0105] a) In the method for preparing the amorphous ribbon of the present invention, the yield of the amorphous ribbon is increased to more than 80% by strictly controlling the process parameters.

[0106] b) The method for preparing the amorphous strip of the present invention adopts a vacuum quenching device with high cooling intensity and good cooling uniformity, which can increase the yield of the amorphous strip to more than 80% (the yield of the amorphous strip in the prior art is about 50%).

[0107] Example 1 (spindle-shaped cooling roller, core barrel following motion)

[0108] This embodiment uses a rotating cooling roller with a shaft diameter of 100mm, a cooling sleeve made of copper, an outer diameter of 380mm, an outer diameter of a core barrel of 304mm, and four parallel spiral grooves on the inner wall of the copper sleeve. The aspect ratio D / h of the spiral grooves is 2.5, and the pitch S is 80mm.

[0109] Example 2 (spindle-shaped cooling roller, core barrel rotation)

[0110] This embodiment is basically the same as the embodiment 1, except that it further includes a locking member (clip) for fixing the core barrel 4 to the rotating shaft 1 so that the core barrel is in a rotating state.

[0111] Comparative Example 1 (Right-angle cooling roller, rotating core barrel)

[0112] Compared with Example 1, the structure of the rotating cooling roller is the structure involved in the patent with patent number ZL201621099453.5.

[0113] Under the same simulation conditions, the velocity field and temperature field of the rotating cooling roller during cooling of Example 1, Example 2 and Comparative Example 1 were analyzed by finite element simulation. The results are as follows: Figure 2-1 , Figure 2-2 , Figure 3-1 and Figure 3-2 The simulation data are shown in Table 1.

[0114]

[0115] It can be seen from the data in Table 1 that the water outlet speed of the spindle-shaped cooling roller (Example 1 and Example 2) of the present invention is significantly greater than the water outlet speed of the right-angle cooling roller (Comparative Example 1). After the cooling medium passes through the spindle-shaped copper roller, the outlet speed is faster, indicating that the cooling medium can take away more heat in a short time, so that the water outlet temperature of the spindle-shaped cooling roller (Example 1 and Example 2) is significantly higher than the water outlet temperature of the right-angle cooling roller (Comparative Example 1), proving that the cooling intensity of the spindle-shaped cooling roller is significantly greater than the cooling intensity of the right-angle cooling roller.

[0116] Furthermore, by comparing the data of Example 1 and Example 2 in Table 1, it is found that, compared with the core barrel rotation (Example 2), the core barrel follower (Example 1) has a faster water outlet speed, and the cooling medium between the cooling jacket and the core barrel has a smaller speed along the tangential direction. The smaller the speed of the cooling medium between the cooling jacket and the core barrel along the tangential direction, the smaller the effect of the centrifugal force. It can be seen that, compared with the core barrel rotation (Example 2), the core barrel follower (Example 1) can further reduce the influence of the centrifugal force, improve the axial passing capacity of the cooling medium, further improve the cooling efficiency, and thus improve the cooling intensity.

[0117] In addition, by Figure 2-1 It can be seen that when the core barrel rotates, the cooling water flow rate is faster (the cloud is red), but Figure 3-1 It can be further known that the fast speed is because its tangential speed is large, that is, it is greatly affected by the centrifugal force, which ultimately causes the outlet speed to be slow.

[0118] The advantages of precise control of process parameters in the method for preparing amorphous ribbons of the present invention are demonstrated below with specific examples and comparative examples.

[0119] Embodiments 3-8 of the present invention provide a method for preparing an amorphous strip. The composition of the amorphous strip is TiZrCuNiNb. The strip prepared in Embodiment 3 is shown in FIG. Figure 7 .

[0120] The preparation method of Examples 3-8 includes: evacuating a vacuum quenching device, melting a master alloy, transferring from a converter to a tundish, starting a rotating cooling roller, and pressurizing a spray belt.

[0121] It should be noted that the equipment used in the vacuum quenching process of Examples 3-8 is a vacuum quenching equipment, and the rotating cooling roller in the vacuum quenching equipment is the cooling roller of Example 1.

[0122] The specific process parameters of Examples 3-8 are shown in Table 2, and the yield of the strip is shown in Table 3.

[0123]

[0124]

[0125] Example 9

[0126] This embodiment is substantially the same as embodiment 6, except that the rotating cooling roller in the vacuum quenching equipment is the cooling roller of embodiment 2. The yield of the strip is shown in Table 3.

[0127] like Figure 4 As shown in FIG. 1 , when the alloy system uses a spindle-shaped copper roller (Example 2, the core barrel rotates) to rotate the cooling roller for vacuum rapid quenching, the strip edge has local crystallization, indicating that the cooling strength of the cooling roller is not enough to prepare a completely amorphous strip. However, the spindle-shaped copper roller (Example 1, the core barrel follows) of the present invention can prepare a strip with bright surface quality, complete strip shape and complete amorphization, as shown in FIG. Figure 5 shown.

[0128] Comparative Example 2

[0129] This comparative example is basically the same as Example 6, except that the rotating cooling roller in the vacuum quenching equipment is the cooling roller of Comparative Example 1. The strip yield is shown in Table 3.

[0130] In addition, the inventors conducted a large number of experimental studies during the research process, and now use some solutions with poor performance as comparative examples. The strip yields of comparative examples 3-8 are shown in Table 3.

[0131] Comparative Example 3

[0132] This comparative example is substantially the same as Example 6, except that the melting temperature is 900°C.

[0133] Comparative Example 4

[0134] This comparative example is substantially the same as Example 6, except that the melting temperature is 1500°C.

[0135] Comparative Example 5

[0136] This comparative example is substantially the same as Example 6, except that the spray belt pressure is 35 kPa.

[0137] Comparative Example 6

[0138] This comparative example is substantially the same as Example 6, except that the spray belt pressure is 65 kPa.

[0139] Comparative Example 7

[0140] This comparative example is basically the same as Example 6, except that the pressure difference between the tundish and the rapid quenching vacuum chamber is 15 kPa.

[0141] Comparative Example 8

[0142] This comparative example is basically the same as Example 6, except that the pressure difference between the tundish and the rapid quenching vacuum chamber is 35 kPa.

[0143] As can be seen from Table 3, the strip yield of Examples 3-8 (85%-90%) is significantly higher than that of Comparative Examples 3 and 5-8 (70%-75%, but still higher than the amorphous strip yield of about 50% in the prior art), indicating that too low melting temperature, too high or too low spray pressure, and too high or too low pressure difference between the tundish and the quenching vacuum chamber will reduce the strip yield, thus proving the importance of process parameter control in the preparation method of amorphous strip. In addition, the strip yield of Comparative Example 4 is comparable to that of Examples 3-8, indicating that too high melting temperature does not contribute to improving the strip yield.

[0144] In addition, it can be seen from Table 3 that the strip yields of Examples 3-8 (85%-90%) and Example 9 (81%) are significantly higher than those of Comparative Example 2, indicating that the use of a spindle-shaped cooling roller can improve the strip yield more than the use of a right-angle cooling roller. In addition, the strip yields of Examples 3-8 (85%-90%) are also higher than the strip yield of Example 9 (81%), indicating that the spindle-shaped cooling roller in the form of a core barrel following motion can improve the strip yield more than the spindle-shaped cooling roller in the form of a core barrel rotating motion.

[0145] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A rotating cooling roller for improving the yield of amorphous strip, characterized in that: The rotating cooling roller comprises a rotating shaft, a flange, a cooling jacket, a core barrel and a rolling bearing; The cooling jacket is a hollow cylinder without end faces, and the two ends of the cooling jacket are respectively connected to a flange, and the other ends of the two flanges are respectively connected to the rotating shaft; the rotating shaft is hollow inside to allow the cooling medium to flow through; The two flanges and the cooling jacket form a spindle-shaped internal space, and the core barrel is arranged in the spindle-shaped internal space, and a gap is left between the core barrel and the flange and the cooling jacket, so as to construct an internal flow path of a spindle-shaped streamline structure for the cooling medium from the rotating shaft to flow through; the streamlined structural design is conducive to overcoming the centrifugal force, and can reduce the influence of the centrifugal force of the high-speed rotation of the cooling roller on the poor internal flow of the cooling medium; The outer shape of the core barrel corresponds to the spindle-shaped internal space, and both ends of the core barrel are respectively connected to the rotating shaft, and rolling bearings are provided at the connection points; It also includes a locking piece, which is arranged at the connection between the core barrel and the rotating shaft to fix the core barrel and the rotating shaft.

2. The rotary cooling roller according to claim 1, characterized in that The flange has a conical structure.

3. The rotary cooling roller according to claim 2, characterized in that The end of the flange with a larger diameter is connected to the cooling jacket, and the end of the flange with a smaller diameter is connected to the rotating shaft.

4. The rotating cooling roller according to claim 1, characterized in that The inner wall of the flange is provided with a guide groove.

5. The rotating cooling roller according to claim 1, characterized in that The gap between the core barrel and the cooling jacket is 5-10 mm on one side.

6. The rotating cooling roller according to claim 1, characterized in that The cooling jacket is made of a material with high thermal conductivity.

7. The rotating cooling roller according to claim 1, characterized in that The inner wall of the cooling jacket is provided with single-path or multi-path spiral grooves.

8. The rotating cooling roller according to claim 7, characterized in that The cross section of the spiral groove is semi-elliptical, semi-circular, triangular, rectangular or trapezoidal.

9. A vacuum quenching equipment, characterized in that: It comprises a rapid quenching vacuum chamber, in which the rotating cooling roller according to any one of claims 1 to 8 is arranged.

10. A method for preparing an amorphous ribbon, characterized in that: The method is prepared by using the vacuum quenching equipment according to claim 9, comprising the following steps: Step 1: Load the brazing master alloy into the melting crucible of the vacuum quenching equipment, evacuate the vacuum, and then fill the vacuum quenching equipment with inert gas; Step 2: Start the melting furnace to melt the brazing master alloy until the brazing master alloy is completely melted; Step 3: Transfer the melted brazing master alloy to a tundish and let it stand; Step 4: Start the rotating cooling roller, pressurize the tundish and spray the belt, and maintain the pressure difference between the tundish and the chamber.

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