Tellurium-copper alloy material and preparation method and application thereof

Abstract

The invention discloses a tellurium-copper alloy material and a preparation method and application thereof, and the tellurium-copper alloy material comprises the following components in percentage by mass: 0.4-0.7% of Te, 0.004-0.012% of P, 0.05-0.15% of Zr, 0.01-0.05% of Cd, 0.01-0.05% of Ge, less than or equal to 9 ppm of oxygen, and the balance of copper and inevitable impurities. Wherein the tellurium-copper alloy material contains intermetallic compounds Te2Zr, TeCd and GeTe, the particle diameter of the intermetallic compounds is 1-20 nm, and the number of the intermetallic compounds per 0.1 mm < 2 > area is more than 1000. Metal zirconium, cadmium and germanium are added into the tellurium-copper alloy and react with metal tellurium to generate an intermetallic compound, enrichment of tellurium particles at the grain boundary is reduced or eliminated, and meanwhile, in the casting process, stepped heating is adopted, extrusion parameters are controlled, and the tellurium-copper alloy material with excellent machining performance and the like is obtained. The method is simple, short in process and high in production efficiency, and has wide application prospects in the fields of electronic appliances and the like.

Description

Technical Field

[0001] The invention belongs to the field of metallurgical material processing, and specifically relates to a tellurium copper alloy material and a preparation method and application thereof. Background Art

[0002] The brand of tellurium copper alloy is C14500. Its main elements are copper, tellurium and a small amount of phosphorus. It has high conductivity, easy cutting, arc resistance, etc. Its conductivity is above 85% IACS, its hardness is above 90HV, and its cutting performance is close to Hpb63-3. It is the material with the best cutting performance among all high-copper alloys. Because tellurium copper has excellent cutting performance and high conductivity, it is used in the fields of plasma cutting, new energy connectors and some high-voltage switches.

[0003] With the strong rise of new energy vehicles in China, the export volume of automobiles has also jumped to the first place in the world, which in turn has led to a surge in the demand for automobile connectors and charging equipment, resulting in a sharp increase in the demand for arc-extinguishing alloy tellurium copper. Traditional tellurium copper is produced by semi-continuous casting → horizontal extrusion → wire drawing → straightening → precision inspection. However, this process has many disadvantages: (1) It cannot be produced continuously, resulting in a long process and low efficiency; (2) It is difficult to produce special-shaped materials; (3) The machining performance is unstable, and it is easy to cause problems such as powder loss and cracking.

[0004] Patent document CN101429601A discloses a tellurium-copper alloy material for the electrical power industry and a preparation method thereof. The preparation method is as follows: after the melting groove of the industrial frequency induction furnace is melted, 99.55-99.89wt% of industrial pure copper is gradually added. After the solid copper is melted, the temperature of the copper liquid is raised to 1190-1230°C, and charcoal is covered to keep it warm; 0.1-0.4wt% of pure tellurium is wrapped and pressed into the bottom of the industrial frequency induction furnace near the melting groove. At this time, the furnace temperature is 1190-1230°C, and after 50-80 minutes, 0.01-0.05wt% of trace elements are added to the tellurium copper alloy liquid. After 15-30 minutes, the tellurium copper alloy liquid is smelted, and the furnace temperature is lowered to 1150-1180°C. The alloy liquid is poured into a graphite crystallizer for crystallization, and then the ingot is pulled by conventional methods, sawed into short ingots of a specified length, and the content is measured by sampling and packaging into products. However, the invention has a complex process and low production efficiency, and the proposed horizontal continuous casting, sawing and other processes cannot improve the casting structure inside the material, and the mechanical properties cannot be applied to electric vehicle charging pile connectors.

[0005] Patent document CN106222477A discloses a tellurium copper alloy, the tellurium copper alloy composition is: tellurium content is 0.16-0.19%, chromium content is 0.07-0.10%, cobalt content is 0.07-0.10%, indium content is 0.011-0.015%, yttrium content is 0.005-0.01%, antimony content is 0.005-0.01%, selenium content is 0.005-0.01%, and oxygen content is less than 0.0005%. The preparation process includes: using the upward continuous casting technology to produce copper rods or semi-continuous technology to produce ingots; homogenization annealing; using a continuous extrusion unit or a traditional horizontal extrusion unit to extrude the tellurium copper alloy; solution treatment; cold rolling; aging; wire drawing. The tellurium copper alloy prepared by the invention has poor high temperature stability, and its preparation process is complex and the efficiency is low.

[0006] Therefore, in view of the above-mentioned deficiencies in the prior art, there is an urgent need to find a method with a simple preparation process, a short production process and high efficiency to produce tellurium copper alloy materials with excellent performance to meet the current market demand for tellurium copper alloys. Summary of the invention

[0007] The purpose of the present invention is to provide a tellurium copper alloy material and its preparation method and application. The tellurium copper alloy material has excellent processing performance and electrical conductivity, and the preparation method is simple, the process is short, and the production efficiency is high, and it can be used in the fields of electronic appliances and the like.

[0008] The first aspect of the present invention provides a tellurium-copper alloy material, comprising the following components in percentage by mass: Te: 0.4-0.7%, P: 0.004-0.012%, Zr: 0.05-0.15%, Cd: 0.01-0.05%, Ge: 0.01-0.05%, oxygen content ≤ 9ppm, and the balance is copper and unavoidable impurities; wherein the tellurium-copper alloy material contains an intermetallic compound Te 2 Zr, TeCd and GeTe, the particle diameter of the intermetallic compound is 1-20nm, and ... 2 The number of intermetallic compounds per area is more than 1000.

[0009] The present invention adds metal zirconium, cadmium and germanium to the tellurium-copper alloy, and the three can react with the metal tellurium to generate the intermetallic compound Te 2 Zr, TeCd and GeTe reduce or eliminate the enrichment of tellurium particles at the grain boundaries, thereby eliminating the brittleness of the material. At the same time, intermetallic compounds can enter the interior of the crystal through extrusion processing, so that the grain boundary bonding strength is further improved, and the material will not crack along the grain boundary when cold working.

[0010] The present invention controls the content of Zr to 0.05-0.15%. When the content of Zr is lower than 0.05%, the high temperature softening resistance of tellurium copper is insufficient, resulting in a reduced service life; when the content of Zr is higher than 0.15%, the electrical conductivity is affected.

[0011] Both Cd and Ge are used to spheroidize the tellurium morphology, converting tellurium from a single substance into a metal compound, entering the crystal and grain boundaries, and eliminating the strip and network structures at the grain boundaries. When the Cd and Ge content is higher than 0.05%, it will affect the conductivity, and when it is lower than 0.01%, the combination with tellurium is insufficient.

[0012] The present invention uses Te 2 The particle diameters of Zr, TeCd and GeTe are controlled within 1-20nm. If the particle diameter is less than 1nm, there will be chip removal problems for cutting performance. If the particle diameter is greater than 20nm, the stress will gradually increase and there will be problems of tool sticking. 2 The area proportion of Zr, TeCd and GeTe is controlled at 0.01-0.2%. Below 0.01%, tellurium is not fully incorporated, and above 0.2%, the material conductivity and machining performance decrease.

[0013] Preferably, the grain size of the tellurium copper alloy material is 18-35 μm.

[0014] Preferably, the tellurium copper alloy material has a tensile strength of more than 265 MPa, an elongation of more than 13%, and a conductivity of more than 90% IACS.

[0015] The second aspect of the present invention provides a method for preparing the tellurium copper alloy material, comprising the following steps: melting raw materials meeting the target composition ratio and then performing casting, extrusion and wire drawing;

[0016] Wherein, a refiner is added during the casting process, and the refiner is a mixture of zirconium, cadmium and germanium;

[0017] Step heating is used in the casting process. The blank is first preheated to 100-120℃, then heated to 300-350℃, and then continued to heat to 500-600℃ before insulation.

[0018] In the present invention, a mixture refiner of zirconium, cadmium and germanium is added during the casting process, and zirconium, cadmium and germanium can react with metal tellurium to transform metal tellurium into an intermetallic compound Te 2 Zr, TeCd and GeTe avoid aggregation and growth at the grain boundaries, thus solving the problems of processing brittleness, cracking and powder loss caused by tellurium. At the same time, the above-mentioned intermetallic compounds can enter the interior of the crystal during the extrusion process, so that the grain boundary bonding strength is further improved, thereby improving the cold processing performance of the material.

[0019] The present invention first preheats the blank to 100-120°C, the main function of which is to remove attached water, and then heats it to 300-350°C, mainly to remove surface bound water and gaseous organic matter, while preparing for subsequent rapid addition; then heats it to 500-600°C for insulation, mainly to eliminate deformation resistance, that is, to eliminate organizational dislocations and lattice distortion defects, promote slip, thereby enhancing the plasticity and toughness of the material, and improving its corrosion resistance, wear resistance and electrical conductivity.

[0020] Preferably, in the refiner, the mass ratio of zirconium, cadmium and germanium is 5-15:1-5:1-5.

[0021] Preferably, the amount of the refiner added is 0.02-0.05% of the total mass of the raw material. More preferably, the amount of the refiner added is 0.03% of the total mass of the raw material. The present invention ensures that tellurium is fully combined and the conductivity and machining performance are not affected by controlling the mass ratio of zirconium, cadmium and germanium in the refiner and the amount of the refiner added. At the same time, step heating is used in the casting process to adjust the particle size and amount of the intermetallic compound, thereby further improving the conductivity and machining performance of the material.

[0022] Preferably, in the casting process of the present invention, a continuous casting process is used to produce the ingot. Specifically, during the smelting process, the raw materials are added to the smelting furnace for melting according to the alloy composition ratio, and a refiner is added during the smelting process. After the composition is qualified, the drawing is arranged, and the drawing temperature is 1150-1180°C, the speed is 300-350mm / min, and the water-cooled inlet and outlet temperature difference is 18-35°C. After drawing for 30 minutes, the bottom blowing device is turned on, and nitrogen is blown in for 30-40 minutes, and then the reducing gas CO is mixed in as required, the bottom blowing pressure is 0.2-0.4MPa, the flow rate is 2-44L / min, and the proportion of the mixed reducing gas CO is 10-40%.

[0023] Preferably, in the casting process of the present invention, a crystallizer is used for cooling, wherein the crystallizer head is provided with a filtering device.

[0024] Preferably, the filtering device is a foam ceramic filter funnel or a graphite filter funnel. The filter funnel has the following main functions: 1. Preventing large suction from sucking in graphite flakes and other substances, resulting in slag inclusion defects. 2. Diverting to ensure temperature consistency. The funnel is provided with an opening to facilitate the diversion of the copper liquid.

[0025] Preferably, the foam ceramic filter funnel or graphite filter funnel is an annular groove structure, and a circular hole is opened on the circumference of the annular groove structure, and the diameter of the circular hole is 5-10mm. If it is less than 5mm, the upper guide rod may become hollow or break due to the inability of the copper water flow to keep up, and if it is greater than 10mm, it may cause slag inclusion due to strong suction.

[0026] According to actual production needs, preferably, the circular holes are distributed in a ring shape on the circumference of the annular groove structure, the number of circles is 3-4 circles, and the number of circular holes is 12-30.

[0027] Preferably, the crystallizer protective cover is 20 cm higher than the melt level. The present invention sets the crystallizer protective cover 20 cm higher than the melt level to ensure that the liquid level is continuously stable, there is sufficient static pressure, the quality of the produced product is stable, and there will be no pores or hollow problems.

[0028] Preferably, the present invention adopts a step-gradient heating tool to perform step-heating on the blank, and the step-gradient heating tool is installed at the entrance of the extruder, and includes a preheating zone, a heating zone and a heating and heat preservation zone connected in sequence. The preheating zone is used to heat the blank to 100-120°C, the heating zone is used to heat the blank temperature to 300-350°C, and the heating and heat preservation zone is used to heat the blank temperature to 500-600°C and keep it warm.

[0029] Preferably, the length of the preheating zone is 800-1600 mm, the length of the heating zone is 800-1600 mm, and the length of the heating and heat preservation zone is 400-1200 mm.

[0030] Preferably, the preheating zone, heating zone and heating and heat preservation zone of the present invention are heated or heat-insulated by high-frequency heating wires. Preferably, the high-frequency heating wire is a nickel-chromium wire, and the shape is preferably annular. The heating zone uses a high-frequency heating wire to quickly raise the temperature to 300-350°C. Since it is a continuous operation, production efficiency needs to be ensured. No tissue phase change occurs in the early stage, and it is only used to soften the tissue and improve production efficiency. After that, the temperature is quickly heated to 500-600°C for heat preservation to eliminate the deformation resistance of the material and promote slippage, thereby enhancing the plasticity and toughness of the material and improving its corrosion resistance, wear resistance and electrical conductivity.

[0031] Preferably, the heating rate of the gradient heating is matched according to the extrusion speed, and preferably the heating rate is 5-200° C. / s.

[0032] The ingot pulled out during the continuous casting process can be continuously extruded to produce round bars, bars, and other special-shaped products. By installing a step-gradient heating tool at the entrance of the extruder, the ingot entering the extruder can be heated to above 500°C, which can ensure that the existing tellurium can be in a molten free and disordered state, eliminating the brittleness of grain boundary processing, and then it can enter the extrusion cavity for normal profile processing and production.

[0033] Preferably, the extrusion is continuous extrusion, the current of the extrusion process is 460-480A, the holding pressure is 20-25MPa, the auxiliary speed is 5-5.5rpm, and the extrusion speed is 1-20m / min. The present invention further regulates the particle size of the intermetallic compound by limiting the continuous extrusion process conditions, thereby further improving its machining performance.

[0034] Preferably, in the wire drawing process, the processing rate is 30-40%. This processing rate range can ensure that the obtained tellurium copper has a tensile strength of more than 260 MPa and a hardness of more than 90 HV, meeting the mechanical property requirements.

[0035] The third aspect of the present invention provides the application of the tellurium copper alloy material in the fields of plasma cutting, new energy connectors and some high-voltage switches. The tellurium copper alloy material of the present invention has excellent electrical conductivity, tensile strength, elongation and small grain size, and excellent processing performance, and has broad application prospects in the fields of new energy connectors and the like.

[0036] Compared with the prior art, the present invention has at least the following beneficial effects:

[0037] (1) The present invention adds metal zirconium, cadmium and germanium to the tellurium-copper alloy, and the three metals can react with the metal tellurium to form an intermetallic compound Te 2 Zr, TeCd and GeTe can reduce or eliminate the enrichment of tellurium particles at the grain boundaries, thereby eliminating the brittleness of the material. At the same time, intermetallic compounds can enter the interior of the crystal through extrusion processing, further improving the grain boundary bonding strength and improving the cold processing performance of the material.

[0038] (2) The present invention improves the crystallizer device by arranging a filter funnel at the head of the crystallizer. On the one hand, it can prevent the occurrence of large suction force that sucks in graphite flakes and other substances, resulting in slag inclusion defects; on the other hand, it can be used for diversion to ensure temperature consistency.

[0039] (3) The present invention adopts step heating during the casting process. The blank is first preheated to 100-120°C to remove attached water, and then heated to 300-350°C to remove bound water and gaseous organic matter on the surface, while preparing for the subsequent rapid addition; then heated to 500-600°C for insulation to eliminate deformation resistance, that is, eliminate structural dislocations and lattice distortion defects, promote slip, thereby enhancing the plasticity and toughness of the material, and improving its corrosion resistance, wear resistance and electrical conductivity.

[0040] (4) The present invention adopts a continuous casting process in the traction process and a continuous extruder in the extrusion process to produce products of various specifications and models, which greatly shortens the production process, reduces production costs and ensures product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a structural schematic diagram of a crystallizer according to an embodiment of the present invention;

[0042] In the figure: 1-inner tube assembly; 2-graphite sleeve; 3-jacket, 4-sealing gasket; 5-outer tube assembly; 6-graphite sleeve guide tube; 7-nut; 8-sealing gasket; 9-connector; 10-cooler head; 11-O-ring; 12-tightening nut; 13-filter funnel.

[0043] Figure 2 is a schematic structural diagram of a filter funnel according to an embodiment of the present invention, wherein Figure 2 a is a cross-sectional view of the filter funnel; Figure 2 b is a top view of the filter funnel.

[0044] Figure 3 It is a schematic diagram of the structure of the step gradient heating tool according to an embodiment of the present invention.

[0045] Figure 4 This is the metallographic image of the product prepared in Example 1.

[0046] Figure 5 This is the metallographic image of the product prepared in Example 2.

[0047] Figure 6 This is the metallographic image of the product prepared in Example 3.

[0048] Figure 7 This is the metallographic image of the product prepared in Example 4.

[0049] Figure 8 This is the metallographic image of the product prepared in Comparative Example 2. DETAILED DESCRIPTION

[0050] The alloy compositions of the embodiments of the present invention and the comparative examples are shown in Table 1.

[0051] Example 1

[0052] Smelting raw materials: electrolytic plate, metal tellurium, phosphor copper, refiner.

[0053] This embodiment produces a specification of Copper rod, the specific production process is as follows:

[0054] A. In a 5t power frequency melting furnace, during the melting process, 5t electrolytic plates are first added to the melting area of ​​the furnace and covered with charcoal with a thickness of 100mm. At the same time, the connected insulation furnace also needs to be covered with graphite flakes with a thickness of more than 10mm. During the process, the crystallizer needs to be installed, and the crystallizer is deep enough to ensure that the upper edge of the crystallizer protective cover is 20mm above the liquid level, and the pull rod billet is drawn. The structure of the crystallizer in this embodiment is as follows Figure 1As shown, it includes an inner tube assembly 1, a graphite sleeve 2, a jacket 3, a sealing gasket 4, an outer tube assembly 5, a graphite sleeve conduit 6, a nut 7, a sealing gasket 8, a joint 9, a cooler head 10, an O-ring 11, a clamping nut 12 and a filter funnel 13; wherein the filter funnel is a foam ceramic filter funnel, which is installed on the head of the crystallizer, and the foam ceramic filter funnel is provided with circular holes distributed in an annular shape, the number of circles is 4, the number of circular holes is 28, and the diameter of the circular holes is 6 mm (the structural schematic diagram of the filter funnel of this embodiment is shown in Figure 2 During the casting process, the guide rod enters the graphite sleeve conduit. After the pull is started, due to the negative pressure, the surrounding copper liquid is pulled out of the funnel through the graphite sleeve conduit, and enters through multiple round holes around the funnel to fill the gap in the funnel, completing the pull. This operation is repeated in the subsequent casting process.

[0055] After the electrolytic copper is completely melted, the temperature is maintained at 1150°C, the liquid surface needs to be covered, 2.85kg of phosphor copper alloy needs to be added, followed by 1.5kg of refiner (the mass ratio of zirconium, cadmium and germanium is 10:3:3), and finally 22.5kg of metal tellurium is added into the furnace. Let it stand for about 3 minutes, take samples for spectral testing, and if the composition is qualified, it can be arranged for pulling.

[0056] B. Start pulling, the pulling temperature is 1160℃, the speed is 320mm / min, the water cooling inlet and outlet temperature difference is 18℃, after 30 minutes of pulling, start the bottom blowing device, blow nitrogen for 35 minutes, and then mix in reducing gas CO as required, accounting for 20%, bottom blowing pressure 0.4MPa, flow rate 4L / min.

[0057] C. The continuous casting rod begins to be extruded, and the continuous casting blank First preheat to 100°C, then heat to 300°C, and then heat to 550°C and keep warm before entering the continuous extruder for extrusion production. During the extrusion process, the current is 462.4A, the holding pressure is 24.7MPa, the auxiliary speed is 5.19rpm, and the extrusion speed is 15m / min. This embodiment uses a step-by-step heating tool to step-heat the preheated blank. The step-by-step heating tool is installed at the entrance of the extruder, including a preheating zone, a heating hot zone, and a heating and heat preservation zone connected in sequence. The continuous casting rod passes through the preheating zone, the heating zone, and then reaches the heating and heat preservation zone. The rod is heated to the set temperature and enters the extruder for continuous extrusion.

[0058] The schematic diagram of the step gradient heating tool structure of this embodiment is as follows Figure 3As shown, the length of the preheating zone is 800mm, the heating rate is 31℃ / s; the length of the heating zone is 1000mm, the heating rate is 51℃ / s; the length of the heating and insulation zone is 600mm, the heating rate is 104℃ / s. The heating temperatures of the preheating zone, heating zone and heating and insulation zone are 100℃, 300℃ and 550℃ respectively. The rod blank directly enters the heating tooling and is heated to the corresponding temperature in the three heating zones, and then insulation is carried out. Install according to requirements The extrusion die can be produced normally.

[0059] D. Extruded blank Then wire drawing is carried out, and the specific process is:

[0060] The conductivity of the tellurium copper rod produced by the above method is 92% IACAS, the oxygen content is 8ppm, the grain size of the material can be 30um, the tensile strength is 265MPa, the elongation is 15%, and the Te 2 The average particle sizes of Zr, TeCd and GeTe are 8um, 12um and 15um respectively. Unit area is 0.01mm 2 The number of intermetallic compounds on is 35,000.

[0061] Figure 4 This is the metallographic diagram of the product of this embodiment. Figure 4 The second phase (Te 2 Zr, Cu 2 Te, TeCd and GeTe) are evenly distributed in the grains and grain boundaries, showing a dispersed distribution, uniform particles, and no banded second phase structure is observed. The cold working properties of the material are significantly improved.

[0062] Example 2

[0063] Smelting raw materials: electrolytic plate, metal tellurium, phosphor copper, refiner.

[0064] This embodiment produces a specification of Copper rod, the specific production process is as follows:

[0065] A. In a 5t power frequency smelting furnace, during the smelting process, a 5t electrolytic plate is first added to the melting area of ​​the furnace, and at the same time, it is covered with charcoal with a thickness of 100mm. At the same time, the connected insulation furnace also needs to be covered with graphite flakes with a thickness of more than 10mm. During the process, the crystallizer needs to be installed, and the crystallizer is deep enough to ensure that the upper edge of the crystallizer protective cover is 30mm above the liquid surface. The foam ceramic filter funnel adopts 4 circles (the crystallizer structure of this embodiment is the same as that of embodiment 1), and the pull rod blank is drawn.

[0066] After the electrolytic copper is completely melted, the temperature is maintained at 1150°C, the liquid level needs to be covered, 3.2kg of phosphor copper needs to be added, and then 1.5kg of refiner (the mass ratio of zirconium, cadmium and germanium is 3:1:1), and finally metal tellurium is added into the furnace. Let it stand for about 3 minutes, take samples for spectral testing, and if the composition is qualified, it can be arranged for pulling.

[0067] B. Start the pulling process with a temperature of 1170°C and a speed of 350 / min. The water-cooling inlet and outlet temperature difference is 25°C. After 30 minutes of pulling process, start the bottom blowing device and blow nitrogen for 40 minutes. Then, mix in reducing gas CO as required, accounting for 25%. The bottom blowing pressure is 0.4MPa and the flow rate is 3L / min.

[0068] C. The continuous casting rod begins to be extruded, and the continuous casting blank First preheat to 100°C, then heat to 300°C, and then heat to 600°C and keep warm before entering the continuous extruder for extrusion production. The current is 466.5A, the holding pressure is 23.8MPa, the auxiliary speed is 4.89rpm, and the extrusion speed is 20m / min.

[0069] The preheating zone of the step gradient heating fixture of this embodiment is 1400mm long, with a heating rate of 24℃ / s; the heating zone is 1400mm long, with a heating rate of 48℃ / s; the heating insulation zone is 600mm long, with a heating rate of 167℃ / s. The heating temperatures of the preheating zone, heating zone and heating insulation zone are 100℃, 300℃ and 600℃ respectively. The rod blank directly enters the heating fixture and is heated to the corresponding temperature in the three heating zones, and then insulation is performed. Install according to requirements The extrusion die can be produced normally.

[0070] D. Extruded blank Then wire drawing is carried out, and the specific process is:

[0071] The conductivity of the tellurium copper rod produced by the above method is 91% IACAS, the oxygen content is 6ppm, the grain size of the material can be below 20um, the tensile strength is above 280MPa, the elongation is 13%, and the Te 2 The average particle sizes of Zr, TeCd and GeTe are 10um, 16um, 13um, and the unit area is 0.01mm 2 The number of intermetallic compounds on is 29,000.

[0072] Figure 5 is the metallographic diagram of the product of this embodiment, Figure 5 The second phase (Te 2 Zr, Cu 2Te, TeCd and GeTe) are evenly distributed in the grains and grain boundaries, showing a dispersed distribution, uniform particles, and no banded second phase structure is observed. The cold working properties of the material are significantly improved.

[0073] Example 3

[0074] Smelting raw materials: electrolytic plate, metal tellurium, phosphor copper, refiner.

[0075] This embodiment produces a specification of Copper rod, the specific production process is as follows:

[0076] A. In a 5t power frequency smelting furnace, during the smelting process, a 5t electrolytic plate is first added to the melting area of ​​the furnace, and at the same time, it is covered with charcoal with a thickness of 100mm. At the same time, the connected insulation furnace also needs to be covered with graphite flakes with a thickness of more than 10mm. During the process, the crystallizer needs to be installed, and the crystallizer is deep enough to ensure that the upper edge of the crystallizer protective cover is 30mm above the liquid surface. The foam ceramic filter funnel adopts 4 circles (the crystallizer structure of this embodiment is the same as that of embodiment 1), and the pull rod blank is drawn.

[0077] After the electrolytic copper is completely melted, the temperature is maintained at 1140℃~1170℃, the liquid level needs to be covered, 3.2kg of phosphor copper needs to be added, and then 1.5kg of refiner (the mass ratio of zirconium, cadmium and germanium is 7:2:2), and finally 23.5kg of metal tellurium is added into the furnace. Let it stand for about 3 minutes, take samples for spectral testing, and if the composition is qualified, it can be arranged for pulling.

[0078] B. Start pulling, the pulling temperature is 1160℃, the speed is 300mm / min, the water cooling inlet and outlet temperature difference is 20℃, after 30 minutes of pulling, start the bottom blowing device, blow nitrogen for 50 minutes, and then mix in reducing gas CO as required, the bottom blowing pressure is 0.4MPa, and the flow rate is 6L / min.

[0079] C. The continuous casting rod begins to be extruded, and the continuous casting blank First preheat to 100℃, then heat to 300℃, then heat to 550℃ and keep warm before entering the continuous extruder for extrusion production, current 479.5A, holding pressure 24.5MPa, auxiliary speed 4.39rpm, extrusion speed 5m / min. The length of the preheating zone of this embodiment is 1600mm, the heating rate is 6℃ / s; the length of the heating hot zone is 1600mm, the heating rate is 10.4℃ / s; the length of the heating and heat preservation zone is 800mm, the heating rate is, and the heating rate is 26℃ / s.

[0080] The heating temperatures of the preheating zone, heating zone and heating and heat preservation zone are 100℃, 300℃ and 550℃ respectively. The rod blank directly enters the heating tooling and is heated to the corresponding temperature in the three heating zones, and then heat preservation is carried out. Installation according to requirements The extrusion die can be produced normally.

[0081] D. Extruded blank Then wire drawing is carried out, and the specific process is:

[0082] The conductivity of the tellurium copper rod produced by the above method is 95% IACAS, the oxygen content is 7ppm, the grain size of the material can be 35um, the tensile strength is 275MPa, the elongation is 13.5%, and the Te 2 The average particle sizes of Zr, TeCd and GeTe are 11um, 12um, 15um, and the unit area is 0.1mm 2 The number of intermetallic compounds on is 30,000.

[0083] Figure 6 is the metallographic diagram of the product of this embodiment, Figure 6 The second phase (Te 2 Zr, Cu 2 Te, TeCd and GeTe) are evenly distributed in the grains and grain boundaries, showing a dispersed distribution, uniform particles, and no banded second phase structure is observed. The cold working properties of the material are significantly improved.

[0084] Example 4

[0085] Smelting raw materials: electrolytic plate, metal tellurium, phosphor copper, refiner.

[0086] This embodiment produces a tellurium copper busbar with a specification of 92×7.2×72×3.6. The specific production process is as follows:

[0087] A. In a 5t power frequency smelting furnace, during the smelting process, a 5t electrolytic plate is first added to the melting area of ​​the furnace, and at the same time, it is covered with charcoal with a thickness of 100mm. At the same time, the connected insulation furnace also needs to be covered with graphite flakes with a thickness of more than 10mm. During the process, the crystallizer needs to be installed, and the crystallizer is deep enough to ensure that the upper edge of the crystallizer protective cover is 30mm above the liquid surface. The foam ceramic filter funnel adopts 4 circles (the crystallizer structure of this embodiment is the same as that of embodiment 1), and the pull rod blank is drawn.

[0088] After the electrolytic copper is completely melted, the temperature is maintained at 1140℃~1170℃, the liquid level needs to be covered, 2.85kg of phosphor copper needs to be added, and then 1.5kg of refiner (the mass ratio of zirconium, cadmium and germanium is 9:2:2), and finally 22.5kg of metal tellurium is added into the furnace. Let it stand for about 3 minutes, take samples for spectral testing, and if the composition is qualified, it can be arranged for pulling.

[0089] B. Start pulling, the pulling temperature is 1150℃, the speed is 320mm / min, the water cooling inlet and outlet temperature difference is 30℃, after 30 minutes of pulling, start the bottom blowing device, blow in nitrogen for 50 minutes, and then mix in reducing gas CO as required, accounting for 35%, bottom blowing pressure is 0.4MPa, flow rate is 6L / min.

[0090] C. The continuous casting rod begins to be extruded, and the continuous casting blank After preheating, it can directly enter the continuous extruder for extrusion production, with a current of 469.5A, a holding pressure of 23.5MPa, an auxiliary speed of 4.99rpm, and an extrusion speed of 10m / min. The preheating zone length of the step gradient heating tooling in this embodiment is 1200mm, and the heating rate is 14℃ / s; the heating hot zone length is 1200mm, and the heating rate is 28℃ / s; the heating and heat preservation zone length is 600mm, and the heating rate is 84℃ / s.

[0091] The heating temperatures of the preheating zone, heating zone and heating and heat preservation zone are 100℃, 300℃ and 600℃ respectively. The rod blank directly enters the heating tooling and is heated to the corresponding temperature in the three heating zones, and then is kept warm. According to the requirements, the extrusion die of 92×10.2×72×5.3 is installed, and normal production can be carried out.

[0092] D. Extruded blank Then wire drawing is carried out, and the specific process is: 92×10.2×72×5.3→92×7.2×72×3.6.

[0093] The conductivity of the tellurium copper busbar produced by the above method is 92% IACAS, the oxygen content is 9ppm, the grain size of the material can be 30um, the tensile strength is 285MPa, the elongation is 14.5%, and the Te 2 The average particle sizes of Zr, TeCd and GeTe are 12um, 16um, 13um respectively, and the unit area is 0.1mm 2 The number of intermetallic compounds on is 31,000.

[0094] Figure 7 is the metallographic diagram of the product of this embodiment, Figure 7 The second phase (Te 2 Zr, Cu 2Te, TeCd and GeTe) are evenly distributed in the grains and grain boundaries, showing a dispersed distribution, uniform particles, and no banded second phase structure is observed. The cold working properties of the material are significantly improved.

[0095] Example 5

[0096] Smelting raw materials: electrolytic plate, metal tellurium, phosphor copper, refiner.

[0097] This embodiment produces a specification of Copper rod, the specific production process is as follows:

[0098] A. In a 5t power frequency smelting furnace, during the smelting process, a 5t electrolytic plate is first added to the melting area of ​​the furnace, and at the same time, it is covered with charcoal with a thickness of 100mm. At the same time, the connected insulation furnace also needs to be covered with graphite flakes with a thickness of more than 10mm. During the process, the crystallizer needs to be installed, and the crystallizer is deep enough to ensure that the upper edge of the crystallizer protective cover is 30mm above the liquid surface. The foam ceramic filter funnel adopts 4 circles (the crystallizer structure of this embodiment is the same as that of embodiment 1), and the pull rod blank is drawn.

[0099] After the electrolytic copper is completely melted, the temperature is maintained at 1140℃~1170℃, the liquid level needs to be covered, 1.78kg of phosphor copper needs to be added, and then 1.5kg of refiner (the mass ratio of zirconium, cadmium and germanium is 12:2:3), and finally 21kg of metallic tellurium is added into the furnace. Let it stand for about 3 minutes, take samples for spectral testing, and if the composition is qualified, it can be arranged for pulling.

[0100] B. Start pulling, the pulling temperature is 1160℃, the speed is 300mm / min, the water cooling inlet and outlet temperature difference is 20℃, after 30 minutes of pulling, start the bottom blowing device, blow nitrogen for 50 minutes, and then mix in reducing gas CO as required, the bottom blowing pressure is 0.4MPa, and the flow rate is 6L / min.

[0101] C. The continuous casting rod begins to be extruded, and the continuous casting blank First preheat to 100℃, then heat to 300℃, then heat to 600℃ and keep warm before entering the continuous extruder for extrusion production, current 480.5A, holding pressure 24.5MPa, auxiliary speed 4.59rpm, extrusion speed 8m / min. The length of the preheating zone in this embodiment is 1600mm, the heating rate is 8.5℃ / s; the length of the heating hot zone is 1600mm, the heating rate is 16.5℃ / s; the length of the heating and heat preservation zone is 1200mm, and the heating rate is 33.5℃ / s.

[0102] The heating temperatures of the preheating zone, heating zone and heating and heat preservation zone are 100℃, 300℃ and 550℃ respectively. The rod blank directly enters the heating tooling and is heated to the corresponding temperature in the three heating zones, and then heat preservation is carried out. Installation according to requirements The extrusion die can be produced normally.

[0103] D. Extruded blank Then wire drawing is carried out, and the specific process is:

[0104] The conductivity of the tellurium copper rod produced by the above method is 96% IACAS, the oxygen content is 8ppm, the grain size of the material can be 25um, the tensile strength is 275MPa, the elongation is 15.5%, and the Te 2 The average particle sizes of Zr, TeCd and GeTe are 9um, 12um, 14um respectively, and the unit area is 0.1mm 2 The number of intermetallic compounds on is 5000.

[0105] Example 6

[0106] Smelting raw materials: electrolytic plate, metal tellurium, phosphor copper, refiner.

[0107] This embodiment produces a specification of Copper rod, the specific production process is as follows:

[0108] A. In a 5t power frequency smelting furnace, during the smelting process, a 5t electrolytic plate is first added to the melting area of ​​the furnace, and at the same time, it is covered with charcoal with a thickness of 100mm. At the same time, the connected insulation furnace also needs to be covered with graphite flakes with a thickness of more than 10mm. During the process, the crystallizer needs to be installed, and the crystallizer is deep enough to ensure that the upper edge of the crystallizer protective cover is 30mm above the liquid surface. The foam ceramic filter funnel adopts 4 circles (the crystallizer structure of this embodiment is the same as that of embodiment 1), and the pull rod blank is drawn.

[0109] After the electrolytic copper is completely melted, the temperature is maintained at 1140℃~1170℃, the liquid level needs to be covered, 2.14kg of phosphor copper needs to be added, and then 1.5kg of refiner (the mass ratio of zirconium, cadmium and germanium is 1:3:2), and finally 21.5kg of metal tellurium is added into the furnace. Let it stand for about 3 minutes, take samples for spectral testing, and if the composition is qualified, it can be arranged for pulling.

[0110] B. Start pulling, the pulling temperature is 1160℃, the speed is 300mm / min, the water cooling inlet and outlet temperature difference is 20℃, after 30 minutes of pulling, start the bottom blowing device, blow nitrogen for 50 minutes, and then mix in reducing gas CO as required, the bottom blowing pressure is 0.4MPa, and the flow rate is 6L / min.

[0111] C. The continuous casting rod begins to be extruded, and the continuous casting blank First preheat to 100℃, then heat to 300℃, then heat to 550℃ and keep warm before entering the continuous extruder for extrusion production, current 479.8A, holding pressure 24.5MPa, auxiliary speed 4.42rpm, extrusion speed 7m / min. The length of the preheating zone of this embodiment is 1600mm, the heating rate is 7.3℃ / s; the length of the heating hot zone is 1600mm, the heating rate is 14.5℃ / s; the length of the heating and heat preservation zone is 1100mm, and the heating rate is 26.5℃ / s.

[0112] The heating temperatures of the preheating zone, heating zone and heating and heat preservation zone are 100℃, 300℃ and 550℃ respectively. The rod blank directly enters the heating tooling and is heated to the corresponding temperature in the three heating zones, and then heat preservation is carried out. Installation according to requirements The extrusion die can be produced normally.

[0113] D. Extruded blank Then wire drawing is carried out, and the specific process is:

[0114] The conductivity of the tellurium copper rod produced by the above method is 95% IACAS, the oxygen content is 6ppm, the grain size of the material can be 30um, the tensile strength is 265MPa, the elongation is 16.5%, and the Te 2 The average particle sizes of Zr, TeCd and GeTe are 10um, 13um, 15um, and the unit area is 0.1mm 2 The number of intermetallic compounds on is 1000.

[0115] Comparative Example 1

[0116] Smelting raw materials: electrolytic plate, metal tellurium, phosphor copper.

[0117] Test production was carried out in a 5t industrial furnace, smelting process:

[0118] One specification is Copper rod, the specific production process is as follows:

[0119] A. In a 5t power frequency smelting furnace, during the smelting process, a 5t electrolytic plate is first added to the melting area of ​​the furnace, and at the same time, it is covered with charcoal with a thickness of 100mm. At the same time, the connected insulation furnace also needs to be covered with graphite flakes with a thickness of more than 10mm. During the process, the crystallizer needs to be installed, and the crystallizer is deep enough to ensure that the upper edge of the crystallizer protection sleeve is 20mm above the liquid surface. The foam ceramic filter funnel adopts 4 circles (the crystallizer structure of this embodiment is the same as that of embodiment 1), and the pull rod blank is drawn.

[0120] After the electrolytic copper is completely melted, the temperature is maintained at 1160°C, the liquid level needs to be covered, 2.85kg of phosphor copper needs to be added, and finally 23.5kg of metallic tellurium is added into the furnace. Let it stand for about 3 minutes, take samples for spectral testing, and if the composition is qualified, pulling can be arranged.

[0121] B. Start pulling, the pulling temperature is 1160℃, the speed is 330mm / min, the water cooling inlet and outlet temperature difference is 20℃, after 30 minutes of pulling, start the bottom blowing device, blow in nitrogen for 40 minutes, and then mix in reducing gas CO as required, accounting for 35%, bottom blowing pressure is 0.4MPa, flow rate is 6L / min.

[0122] C. The continuous casting rod begins to be extruded, and the continuous casting blank After preheating, it can directly enter the continuous extruder for extrusion production. The current is 466.5A, the holding pressure is 24.5MPa, and the auxiliary speed is 4.89rpm. Normal production cannot be carried out, the copper rod cracks, and extrusion cannot continue.

[0123] Comparative Example 2

[0124] Smelting raw materials: electrolytic plate, metal tellurium, phosphor copper.

[0125] Test production was carried out in a 3t medium frequency furnace, smelting process:

[0126] One specification is Copper rod, the specific production process is as follows:

[0127] A. In a 3t medium frequency melting furnace, during the melting process, 3t electrolytic plates are first added to the melting area of ​​the furnace and covered with charcoal with a thickness of 100mm. During the process, the crystallizer needs to be installed, and the crystallizer pouring pipe is deep enough to ensure that the upper edge of the crystallizer protective cover is 20mm above the liquid surface, and the ingot is pulled.

[0128] After the electrolytic copper is completely melted, the temperature is maintained at 1160℃, the liquid level needs to be covered, 3.2kg of phosphor copper needs to be added, and finally 2.5kg of metallic tellurium is added into the furnace. Let it stand for about 3 minutes, take samples for spectral testing, and if the composition is qualified, pulling can be arranged.

[0129] B. Start casting, the drawing temperature is 1200℃, the speed is 75mm / min, the water cooling inlet and outlet temperature difference is 20℃, after 30 minutes of drawing, start the bottom blowing device, blow in nitrogen for 40 minutes, and then mix in reducing gas CO as required, accounting for 30%, bottom blowing pressure 0.4MPa, flow rate 4L / min.

[0130] C. The ingot begins to be extruded, the extrusion temperature is 850℃, and the extrusion specifications are

[0131] D. Extruded blank Then wire drawing is carried out, and the specific process is:

[0132] The tellurium copper rod produced by the above method has a conductivity of 91% IACAS, an oxygen content of 8 ppm, a grain size of 30 um, a tensile strength of 285 MPa, and an elongation of 12.5%.

[0133] Figure 8 is the metallographic diagram of the product of this embodiment, Figure 8 It is known that the second phase is enriched at the grain boundary and is in an enriched state, and the cold working performance is poor.

[0134] Table 1 Compositions of Examples of the Invention and Comparative Examples (wt%)

[0135] serial number Te P Zr Cd Ge Example 1 0.45 0.008 0.08 0.02 0.035 Example 2 0.47 0.009 0.07 0.03 0.045 Example 3 0.47 0.009 0.07 0.04 0.045 Example 4 0.45 0.008 0.1 0.03 0.035 Example 5 0.42 0.005 0.006 0.01 0.015 Example 6 0.43 0.006 0.005 0.015 0.01 Comparative Example 1 0.47 0.008 - - - Comparative Example 2 0.5 0.009 - - -

[0136] Table 2 Performance of the products of the embodiments of the present invention and the comparative examples

[0137]

Claims

1. A tellurium copper alloy material, characterized in that: The invention comprises the following components in percentage by weight: Te: 0.4-0.7%, P: 0.004-0.012%, Zr: 0.05-0.15%, Cd: 0.01-0.05%, Ge: 0.01-0.05%, oxygen content ≤ 9ppm, and the balance is copper and unavoidable impurities; wherein the tellurium copper alloy material contains intermetallic compounds Te2Zr, TeCd and GeTe, the particle diameter of the intermetallic compound is 1-20nm, and each 0.1mm 2 The number of intermetallic compounds per area is more than 1000.

2. The method for preparing a tellurium-copper alloy material according to claim 1, characterized in that: The method comprises the following steps: melting raw materials meeting the target composition ratio and then performing casting, extrusion and wire drawing; wherein a refiner is added during the casting process, the refiner being a mixture of zirconium, cadmium and germanium; Step heating is used in the casting process. The blank is first preheated to 100-120℃, then heated to 300-450℃, and then continued to heat to 500-600℃ before being kept warm.

3. The preparation method according to claim 2, characterized in that: In the refiner, the mass ratio of zirconium, cadmium and germanium is 5-15:1-5:1-5; and the added amount of the refiner is 0.02-0.05% of the total mass of the raw materials.

4. The preparation method according to claim 2, characterized in that: The casting is continuous casting, and a crystallizer with a filtering device at the head is used for cooling during the casting process. The filtering device is preferably a foam ceramic filtering funnel or a graphite filtering funnel.

5. The preparation method according to claim 4, characterized in that: The foam ceramic filter funnel or graphite filter funnel is in an annular groove structure, with a circular hole on the circumference, and the diameter of the circular hole is 5-10 mm.

6. The preparation method according to claim 5, characterized in that: The circular holes are distributed in a ring shape on the peripheral surface of the foam ceramic filter funnel or the graphite filter funnel with an annular groove structure, the number of circles is 3-4 circles, and the number of the circular holes is 12-30.

7. The preparation method according to claim 2, characterized in that: The step-gradient heating tool is used to perform step-heating on the blank. The step-gradient heating tool is installed at the entrance of the extruder, and includes a preheating zone, a heating zone and a heating insulation zone connected in sequence. The length of the preheating zone is 800-1600mm, the length of the heating zone is 800-1600mm, and the length of the heating insulation zone is 400-1200mm.

8. The preparation method according to claim 7, characterized in that: The preheating zone, heating zone and heating and heat preservation zone are heated or heat-insulated by high-frequency heating wires; the heating rate of the gradient heating is 5-200°C / s.

9. The preparation method according to claim 2, characterized in that: The extrusion is continuous extrusion, the current of the extrusion process is 460-480A, the holding pressure is 20-25MPa, the auxiliary speed is 5-5.5rpm, and the extrusion speed is 1-20m / min.

10. Application of the tellurium copper alloy material according to claim 1 in the fields of plasma cutting, new energy connectors or high voltage switches.

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