A method for manufacturing a Cu-Cr-Nb-RE material guide rail for an electromagnetic rail gun

Abstract

The invention discloses a method for manufacturing a Cu-Cr-Nb-RE material guide rail for an electromagnetic rail gun, comprising the following steps: S1, preparing a blank, including material vacuum induction melting, vacuum electrode gas atomization powder making, and hot isostatic pressing; S2, forging; S3, primary annealing; S4, rough rolling; S5, secondary annealing; S6, intermediate rolling; S7, machining; Cr and Nb in the Cu-Cr-Nb-RE material manufactured by the invention form a large amount of Cr2Nb strengthening phase, which is evenly dispersed in the alloy, can refine and control the grain size of copper, and the Cr2Nb phase is still stable when it exceeds 1600°C, avoiding the problems of fatigue and ablation of the hot end part of the material at high temperature. The Cu-Cr-Nb-RE material guide rail manufactured by the method of the invention not only has high strength and high electrical conductivity, but also has a high softening temperature and a comprehensive performance of high temperature ablation resistance, which significantly improves a series of problems existing in the current guide rail.

Description

Technical Field

[0001] The invention relates to the technical field of alloy material preparation, and in particular to a method for manufacturing a Cu-Cr-Nb-RE material guide rail for an electromagnetic rail gun. Background Art

[0002] As a new type of weapon and equipment for information warfare, the electromagnetic railgun has the characteristics of fast speed, long range, strong anti-interference ability and high battlefield survivability. It has huge potential advantages and broad application prospects in both military and civilian fields. When the switch is closed, the current-carrying armature is accelerated by the Lorentz force in the magnetic field generated by the track current, and the projectile is ejected. Although the principle is simple, the development of electromagnetic railguns is restricted by many practical problems. Among them, the electromagnetic track is in a harsh working environment of high current, high temperature and strong magnetic field. The guide rail material is required to have not only sufficient rigidity and strength to resist the electromagnetic force, but also good conductivity and ablation resistance. At present, its damage forms mainly include surface gouging, transition and arc ablation, and current-carrying friction wear, which leads to a short service life of the track and great difficulty in maintenance, thus greatly restricting its development.

[0003] Launch rail technology is one of the key technologies of electromagnetic rail guns. Since the rail works under the current of megaampere level, the material must withstand the instantaneous huge heat flow impact, which can easily cause serious ablation of the rail. Therefore, the rail material must not only have sufficient strength and rigidity, but also must be able to withstand the strong current of 3 to 4 megaamperes. At the same time, the rail is the largest load-bearing component, and its material is required to have sufficient rigidity and strength to resist electromagnetic force and have good conductivity. The rails of electromagnetic rail guns are usually made of thick copper strips or other conductive materials, which are embedded in the barrel of the gun in parallel. Experiments on rail materials and ablation effects show that the rail gun using tungsten has the smallest ablation. However, tungsten is expensive and has poor strength, so it is not suitable as a material for rail guns.

[0004] Therefore, it is necessary to design a method for manufacturing Cu-Cr-Nb-RE material guide rails for electromagnetic railguns, comprehensively consider the excellent comprehensive properties of copper alloys, develop high-strength, high-conductivity, ablation-resistant copper alloy materials suitable for electromagnetic railgun guide rails, and solve the problems of short life and low reliability currently faced by guide rails. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a method for manufacturing a Cu-Cr-Nb-RE material guide rail for an electromagnetic rail gun.

[0006] The technical solution of the present invention is: a method for manufacturing a Cu-Cr-Nb-RE material guide rail for an electromagnetic rail gun, comprising the following steps:

[0007] S1. Prepare the blank:

[0008] The raw materials are smelted to obtain a Cu-Cr-Nb-RE alloy ingot, the alloy ingot is powdered by vacuum electrode gas atomization to obtain a Cu-Cr-Nb-RE alloy powder, and the alloy powder is finally hot isostatically pressed to obtain a Cu-Cr-Nb-RE material;

[0009] The raw materials include: 5.0-8.0wt% of chromium-niobium master alloy, 0.05-0.10wt% of rare earth element RE, and the balance is electrolytic copper plate;

[0010] S2. Forging:

[0011] Forging the material blank obtained in step S1 to obtain a forged square billet, wherein the forging temperature is 850-950° C., the temperature is kept for 80-150 minutes, and the deformation amount per forging is 30-50%;

[0012] S3, primary annealing:

[0013] Annealing the forged billet obtained in step S2 to obtain a primary annealed billet, wherein the annealing temperature is 600-800° C. and the temperature is kept for 1-4 hours;

[0014] S4, rough rolling:

[0015] The once annealed billet obtained in step S3 is subjected to rough rolling to obtain a rough rolled billet, wherein the rolling deformation amount of the rough rolling is 60 to 90%;

[0016] S5, secondary annealing:

[0017] Annealing the rough rolled billet obtained in step S4 to obtain a secondary annealed billet, wherein the secondary annealing temperature is 600-800° C. and the temperature is kept for 1-4 hours;

[0018] S6, medium rolling:

[0019] The secondary annealed billet obtained in step S5 is subjected to intermediate rolling to obtain an intermediate rolled billet, wherein the rolling deformation amount of the intermediate rolling is 50 to 80%;

[0020] S7, machining:

[0021] The intermediate rolled billet obtained in step S6 is machined to obtain a guide rail.

[0022] Description: The Cu-Cr-Nb-RE material alloy guide rail obtained by the manufacturing method of the present invention not only has high strength and high conductivity, but also has the comprehensive performance of high softening temperature and high temperature ablation resistance, which significantly improves a series of problems existing in the current guide rail.

[0023] Furthermore, the Cu-Cr-Nb-RE material prepared in step S1 includes 3.0-4.0wt% of alloy chromium, 2.5-3.5wt% of niobium, 0.05-0.10% of rare earth element RE, Fe≤0.03wt%, Si≤0.01wt%, Al≤0.01wt%, O≤0.02wt%, and the balance is metallic copper.

[0024] Description: The Cu-Cr-Nb-RE material guide rail manufactured by the present invention forms a large amount of Cr2Nb strengthening phase due to the Cr and Nb in the alloy, which is evenly dispersed in the alloy, can refine and control the grain size of copper, and further improve the strength of the copper alloy. In addition, the Cr2Nb phase is still stable when it exceeds 1600°C, which can prevent the coarsening of grains or oxidation or melting of grain boundaries at high temperatures, and avoid problems such as fatigue and ablation of the hot end part of the material at high temperatures.

[0025] Furthermore, the content of niobium in the chromium-niobium master alloy is 45-50wt%, and the balance is chromium. The content of copper in the electrolytic copper plate is greater than 99.97wt%.

[0026] Description: Niobium can increase the hardness, heat resistance and corrosion resistance of the alloy, while reducing the thermal expansion coefficient of the alloy and enhancing the plasticity and toughness of the material. High-purity electrolytic copper plate can ensure the purity and uniformity of the alloy, thereby improving the mechanical properties and processing properties of the alloy.

[0027] Furthermore, in step S1, the smelting is vacuum induction melting, and the vacuum induction melting includes the following steps:

[0028] S1-1. Melting:

[0029] The electrolytic copper plate is added into a vacuum induction melting furnace, and after melting, the chromium-niobium master alloy is added, and heating and melting are continued. When the heating temperature rises to 1500-1700° C., rare earth element RE is added;

[0030] S1-2, Refining:

[0031] After all the raw materials in the crucible are melted, refine for 10 to 40 minutes;

[0032] S1-3, pouring:

[0033] Then, a Cu-Cr-Nb-RE material alloy ingot is cast.

[0034] Description: Through the above steps, the vacuum induction melting furnace melts the raw materials, and the obtained Cu-Cr-Nb-RE material has high purity and uniform distribution of components. It can refine and control the grain size of copper. The alloy has high strength, high conductivity and high temperature ablation resistance.

[0035] Furthermore, in step S1, the cooling rate of the atomized powder is 10 2 -10 7 K / ℃, and the alloy powder particle size is less than 150μm.

[0036] Description: Atomization powder making ensures that the microstructure of the alloy powder is very fine. The particle size of the alloy powder is less than 150μm, which can increase the surface area of ​​the alloy powder, has high chemical uniformity and microstructural uniformity, and the powder surface is smooth without cracks and pores.

[0037] Furthermore, in step S1, the hot isostatic pressing temperature is 800-1000° C., the pressure is 100-200 MPa, and the time is 2-5 hours.

[0038] Description: By subjecting the alloy powder to hot isostatic pressing, the alloy powder is first preheated at high temperature, then placed in a mold and subjected to static pressure to form it into the desired shape, and heat treated at high temperature to further improve its density and performance; hot isostatic pressing can effectively remove gas pores and oxides from the alloy powder, and can form a tighter bond between the particles of the alloy powder, thereby increasing its density and strength, and improving its wear resistance and corrosion resistance. In addition, hot isostatic pressing can also obtain a finer grain structure, improve the plasticity and ductility of the material, and make the prepared Cu-Cr-Nb-RE material have better physical properties.

[0039] Furthermore, during refining in step S1-2, an adsorber is placed on the surface, the adsorber material is porous zirconia, the obtained alloy melt is cooled in situ on the crucible to obtain a solidified cooled billet, the top of which is cut off, and the cut solidified cooled billet is returned to the furnace for melting again.

[0040] Description: The impurities on the surface of the solution are removed by an adsorber, and the upper part containing impurities is cut off after solidification to improve the purity of the Cu-Cr-Nb-RE material.

[0041] Furthermore, before step S1-1, the vacuum induction melting furnace is preheated at a temperature of 700 to 900°C for 1 to 4 hours, and the vacuum degree is drawn to 10 -3 ~10 -1 Pa, and then introduce argon gas to 0.8~0.95×10 5 Pa, and evacuate to 10 -3 ~10 -1 Pa;

[0042] In step S1-1, the electrolytic copper plate and the chromium-niobium master alloy are melted respectively. The electrolytic copper plate is melted once, the melting temperature is 1080-1100°C, the melting time is 30-180 minutes, and during the melting, argon gas is filled into the vacuum chamber to 0.8-0.95×10 5 Pa, and evacuate to 10 -3 ~10 -1 Pa, when the melting amount of the electrolytic copper plate reaches 2 / 5 to 3 / 5 of the total amount, the heating power is reduced by 6 to 9 kW, and at the same time, argon is introduced into the melting electrolytic copper plate in a bottom blowing manner, with an argon flow rate of 0.5 to 0.8 L / min, so that the argon and the electrolytic copper plate melt are fully mixed;

[0043] The chromium-niobium master alloy is smelted twice. The first smelting temperature of the chromium-niobium master alloy is 1600-1700°C. When melting begins, argon gas is introduced into the melting chromium-niobium master alloy in a bottom blowing manner into the vacuum chamber. The argon gas flow rate is 0.1-0.4L / min. After smelting for 50-120min, the master alloy is cooled in situ. After cooling for 80-240min, the second smelting is started. The master alloy is vacuumized to 10 -3 ~10 -1 Pa, the second melting temperature of the chromium-niobium master alloy is 1550-16500°C, the melting time is 30-120min, and when the melting time is 15-60min, argon gas is introduced into the vacuum chamber by bottom blowing, and the argon gas flow rate is 0.8-1.2L / min, to obtain a chromium-niobium master alloy liquid;

[0044] Subsequently, the chromium-niobium intermediate alloy liquid after two smeltings is added to the electrolytic copper plate after one smelting, and argon gas is introduced into the electrolytic copper plate by bottom blowing, and the argon gas flow rate is 1.5-1.9L / min. When the heating temperature rises to 1500-1700°C, rare earth element RE is added, and argon gas with a flow rate of 2.5-2.9L / min is introduced into the electrolytic copper plate by bottom blowing again, and heating and melting are continued.

[0045] Note: Preheating can ensure the uniformity and stability of the raw materials and improve the melting efficiency. In addition, preheating can also remove moisture and gas on the surface of the raw materials to reduce bubbles and defects in the gold raw materials during melting. Melting in a vacuum environment can greatly reduce the gas and impurities on the metal surface, thereby obtaining a purer and more uniform material. During melting, argon gas is introduced in stages to reduce the oxygen content of the material, so that the oxygen content in the Cu-Cr-Nb-RE material guide rail is reduced to less than 8ppm.

[0046] Furthermore, in step S1-1, during the process of introducing argon gas, the pressure in the vacuum induction melting furnace is ensured to be ≤10 - 1 Pa.

[0047] Description: The low pressure in the vacuum induction melting furnace can effectively improve the purity, quality and efficiency of the preparation of Cu-Cr-Nb-RE materials, and is an important process parameter of the vacuum induction melting furnace.

[0048] The beneficial effects of the present invention are:

[0049] (1) The Cu-Cr-Nb-RE material guide rail prepared by the present invention solves the problems of short life and low reliability faced by the current electromagnetic rail gun guide rails, and overcomes the problems of short service life and difficult maintenance of the guide rails due to surface planing, transition and arc ablation of the guide rail material and current-carrying friction wear in the prior art.

[0050] (2) The Cu-Cr-Nb-RE material guide rail obtained by the manufacturing method of the present invention forms a large amount of Cr2Nb strengthening phase due to the Cr and Nb in the alloy, which is evenly dispersed in the alloy, can refine and control the grain size of copper, and further improve the strength of the copper alloy. In addition, the Cr2Nb phase is still stable at more than 1600°C, which can prevent the coarsening of grains or oxidation or melting of grain boundaries at high temperatures, and avoid problems such as fatigue and ablation of the hot end part of the material at high temperatures.

[0051] (3) The Cu-Cr-Nb-RE material alloy guide rail obtained by the manufacturing method of the present invention not only has high strength and high conductivity, but also has a high softening temperature and comprehensive performance of high temperature ablation resistance, which significantly improves a series of problems existing in the current guide rail. DETAILED DESCRIPTION

[0052] The present invention is further described in detail below in conjunction with specific implementation methods to better reflect the advantages of the present invention.

[0053] Example 1

[0054] A method for manufacturing a Cu-Cr-Nb-RE material guide rail for an electromagnetic rail gun comprises the following steps:

[0055] S1. Prepare the blank:

[0056] The raw materials are smelted to obtain a Cu-Cr-Nb-RE alloy ingot, and the alloy ingot is powdered by vacuum electrode gas atomization. The cooling rate of the atomized powder is 10 2 K / ℃, the alloy powder particle size is 15-150μm, and Cu-Cr-Nb-RE alloy powder is obtained. The alloy powder is finally hot isostatically pressed to obtain Cu-Cr-Nb-RE material. The hot isostatic pressing temperature is 800℃, the pressure is 100MPa, and the time is 2h;

[0057] The raw materials include: 5.56wt% of chromium-niobium master alloy, 0.05wt% of rare earth element RE (La-Ce master alloy), and the balance is electrolytic copper plate;

[0058] The content of niobium in the chromium-niobium master alloy is 45wt%, and the balance is chromium. The content of copper in the electrolytic copper plate is 99.98wt%.

[0059] The smelting is vacuum induction melting, which includes the following steps:

[0060] S1-1. Melting:

[0061] The electrolytic copper plate is added into a vacuum induction melting furnace, and after melting, the chromium-niobium master alloy is added, and heating is continued to melt, and when the heating temperature rises to 1500° C., rare earth element RE is added;

[0062] S1-2, Refining:

[0063] After all the raw materials in the crucible are melted, refine for 15 minutes;

[0064] S1-3, pouring:

[0065] Then, a Cu-Cr-Nb-RE material alloy ingot is cast;

[0066] S2. Forging:

[0067] Forging the material obtained in step S1 to obtain a forged square billet, wherein the forging temperature is 850° C., the temperature is kept for 80 minutes, and the deformation amount per forging is 30%;

[0068] S3, primary annealing:

[0069] Annealing the forged billet obtained in step S2 to obtain a primary annealed billet, wherein the annealing temperature is 600° C. and the temperature is kept for 4 hours;

[0070] S4, rough rolling:

[0071] The once annealed billet obtained in step S3 is subjected to rough rolling to obtain a rough rolled billet, wherein the rolling deformation amount of the rough rolling is 60%;

[0072] S5, secondary annealing:

[0073] Annealing the rough rolled billet obtained in step S4 to obtain a secondary annealed billet, wherein the secondary annealing temperature is 600° C. and the temperature is kept for 4 hours;

[0074] S6, medium rolling:

[0075] The secondary annealed billet obtained in step S5 is subjected to intermediate rolling to obtain an intermediate rolled billet, wherein the intermediate rolling deformation is 50%;

[0076] S7, machining:

[0077] The intermediate rolled billet obtained in step S6 is machined to obtain a Cu-Cr-Nb-RE material guide rail.

[0078] Example 2

[0079] The difference between this embodiment and embodiment 1 is that S1, preparing the blank:

[0080] The required raw materials are smelted to obtain a Cu-Cr-Nb-RE alloy ingot, and the alloy ingot is powdered by vacuum electrode gas atomization. The cooling rate of the atomized powder is 10 2 K / ℃, the alloy powder particle size is 20-100μm, and Cu-Cr-Nb-RE alloy powder is obtained. The alloy powder is finally hot isostatically pressed to obtain Cu-Cr-Nb-RE material. The hot isostatic pressing temperature is 800℃, the pressure is 100MPa, and the time is 2h;

[0081] The raw materials include: 6.25wt% of chromium-niobium master alloy, 0.08wt% of rare earth element RE (La-Ce master alloy), and the balance is electrolytic copper plate;

[0082] The chromium-niobium master alloy has a niobium content of 48wt% and a chromium content as the remainder, and the electrolytic copper plate has a copper content of 99.98wt%;

[0083] The smelting is vacuum induction melting, which includes the following steps:

[0084] S1-1. Melting:

[0085] The electrolytic copper plate is added into a vacuum induction melting furnace, and after melting, the chromium-niobium master alloy is added, and heating is continued to melt, and when the heating temperature rises to 1600° C., rare earth element RE is added;

[0086] S1-2, Refining:

[0087] After all the raw materials in the crucible are melted, refine for 25 minutes;

[0088] S1-3, pouring:

[0089] Then, a Cu-Cr-Nb-RE material alloy ingot is cast;

[0090] S2. Forging:

[0091] Forging the material obtained in step S1 to obtain a forged square billet, wherein the forging temperature is 950° C., the temperature is kept for 150 minutes, and the deformation amount per forging is 50%;

[0092] S3, primary annealing:

[0093] Annealing the forged billet obtained in step S2 to obtain a primary annealed billet, wherein the annealing temperature is 700° C. and the temperature is kept for 2 hours;

[0094] S4, rough rolling:

[0095] The once annealed billet obtained in step S3 is subjected to rough rolling to obtain a rough rolled billet, wherein the rolling deformation amount of the rough rolling is 75%;

[0096] S5, secondary annealing:

[0097] Annealing the rough rolled billet obtained in step S4 to obtain a secondary annealed billet, wherein the secondary annealing temperature is 700° C. and the temperature is kept for 2 hours;

[0098] S6, medium rolling:

[0099] The secondary annealed billet obtained in step S5 is subjected to intermediate rolling to obtain an intermediate rolled billet, wherein the intermediate rolling deformation is 65%;

[0100] S7, machining:

[0101] The intermediate rolled billet obtained in step S6 is machined to obtain a Cu-Cr-Nb-RE material guide rail.

[0102] Example 3

[0103] The difference between this embodiment and embodiment 1 is that S1, preparing the blank:

[0104] The electrolytic copper plate, chromium-niobium master alloy and rare earth element RE are smelted to obtain a Cu-Cr-Nb-RE alloy ingot, and the alloy ingot is powdered by vacuum electrode gas atomization. The cooling rate of the atomized powder is 10 2 K / ℃, the alloy powder particle size is 50-100μm, and Cu-Cr-Nb-RE alloy powder is obtained. The alloy powder is finally hot isostatically pressed to obtain Cu-Cr-Nb-RE material. The hot isostatic pressing temperature is 1000℃, the pressure is 200MPa, and the time is 5h;

[0105] The raw materials include: 8.0wt% of chromium-niobium master alloy, 0.10wt% of rare earth element RE (La-Ce master alloy), and the balance is electrolytic copper plate;

[0106] The content of niobium in the chromium-niobium master alloy is 50wt%, and the balance is chromium. The content of copper in the electrolytic copper plate is 99.98wt%.

[0107] The smelting is vacuum induction melting, which includes the following steps:

[0108] S1-1. Melting:

[0109] The electrolytic copper plate is added into a vacuum induction melting furnace, and after melting, the chromium-niobium master alloy is added, and heating is continued to melt, and rare earth element RE is added when the heating temperature rises to 17000° C.;

[0110] S1-2, Refining:

[0111] After all the raw materials in the crucible are melted, refine for 40 minutes;

[0112] S1-3, pouring:

[0113] Then, a Cu-Cr-Nb-RE material alloy ingot is cast;

[0114] S2. Forging:

[0115] Forging the material obtained in step S1 to obtain a forged square billet, wherein the forging temperature is 950° C., the temperature is kept for 150 minutes, and the deformation amount per forging is 50%;

[0116] S3, primary annealing:

[0117] Annealing the forged billet obtained in step S2 to obtain a primary annealed billet, wherein the annealing temperature is 800° C. and the temperature is kept for 1 hour;

[0118] S4, rough rolling:

[0119] The once annealed billet obtained in step S3 is subjected to rough rolling to obtain a rough rolled billet, wherein the rolling deformation amount of the rough rolling is 90%;

[0120] S5, secondary annealing:

[0121] Annealing the rough rolled billet obtained in step S4 to obtain a secondary annealed billet, wherein the secondary annealing temperature is 800° C. and the temperature is kept for 1 hour;

[0122] S6, medium rolling:

[0123] The secondary annealed billet obtained in step S5 is subjected to intermediate rolling to obtain an intermediate rolled billet, wherein the intermediate rolling deformation is 80%;

[0124] S7, machining:

[0125] The intermediate rolled billet obtained in step S6 is machined to obtain a Cu-Cr-Nb-RE material guide rail.

[0126] Example 4

[0127] Before step S1-1, the vacuum induction melting furnace is preheated at 800°C for 2 hours and the vacuum degree is drawn to 10 -2 Pa, and then argon was introduced to 0.9×10 5 Pa, and evacuate to 10 -2 Pa;

[0128] In step S1-1, the electrolytic copper plate and the chromium-niobium master alloy are melted respectively. The electrolytic copper plate is melted once, the melting temperature is 1090°C, the melting time is 150 min, and during the melting, argon gas is filled into the vacuum chamber to 0.9×10 5 Pa, and evacuate to 10 -2 Pa, when the melting amount of the electrolytic copper plate reaches 2 / 5 of the total amount, the heating power is reduced by 6kW, and argon is introduced into the melting electrolytic copper plate by bottom blowing at a flow rate of 0.65L / min to fully mix the argon with the electrolytic copper plate melt;

[0129] The chromium-niobium master alloy was smelted twice. The first smelting temperature of the chromium-niobium master alloy was 1650℃. When the melting started, argon was introduced into the melting chromium-niobium master alloy in the vacuum chamber by bottom blowing. The argon flow rate was 0.3L / min. After smelting for 100min, the master alloy was cooled in situ. After cooling for 160min, the second smelting was started and the vacuum was evacuated to 10 -2 Pa, the second melting temperature of the chromium-niobium master alloy is 1600°C, the melting time is 80 min, and when the melting reaches 400 min, argon gas is introduced into the vacuum chamber by bottom blowing, and the argon gas flow rate is 1.0 L / min, to obtain a chromium-niobium master alloy liquid;

[0130] Subsequently, the chromium-niobium intermediate alloy liquid after two smeltings was added to the electrolytic copper plate after one smelting, and argon gas was introduced into the plate by bottom blowing with a flow rate of 1.7 L / min. When the heating temperature rose to 1700°C, rare earth element RE was added, and argon gas was introduced into the plate by bottom blowing with a flow rate of 2.7 L / min again to continue heating and melting.

[0131] Experimental example

[0132] The material process parameters prepared in each embodiment are shown in Table 1;

[0133] Table 1 Process parameters

[0134]

[0135]

[0136]

[0137] It can be seen from the above table that the Cu-Cr-Nb-RE materials prepared in Examples 1-3 all meet the requirements. The preferred temperature for the primary annealing and the secondary annealing is 700°C, and the time is preferably 2 to 3 hours. Based on production cost and time considerations, the preparation method of Example 2 is better.

[0138] The physical properties of the Cu-Cr-Nb-RE material guide rails prepared in various embodiments were measured, and the specific research is as follows;

[0139] Examples 1 to 4 are used as experimental examples for comparison;

[0140] Meanwhile, comparative example 1 is set: vacuum induction melting of Cu-Cr alloy is performed to obtain a Cu-Cr copper ingot (round ingot), and the ingot is subjected to hot extrusion, cold drawing and heat treatment to obtain a Cu-Cr guide rail blank;

[0141] Comparative Example 2: During vacuum induction melting of raw materials, the electrolytic copper plate and the chromium-niobium master alloy are not melted in advance. After the electrolytic copper plate is melted at 1080° C., the temperature is raised to 1550° C., and the chromium-niobium master alloy is added to melt. When the heating temperature rises to 1600° C., the rare earth element RE is added;

[0142] 1. Take three samples of the Cu-Cr-Nb-RE material guide rail and the Cu-Cr material guide rail prepared in Examples 1 to 3 and Comparative Example 1, respectively, and test the chromium, niobium, RE and oxygen contents according to the method of GB / T5121;

[0143] Table 2 Chromium, niobium, RE and oxygen content of material guide rails

[0144]

[0145]

[0146] 2. Take the Cu-Cr-Nb-RE and Cu-Cr material guide rail samples prepared in Examples 1 to 3 and Comparative Example 1 respectively, and test their mechanical properties, electrical conductivity, softening temperature and ablation resistance test. The test results are shown in Table 3 below;

[0147] Table 3 Material guide rail performance test table

[0148]

[0149] The tensile strength is tested according to the method of GB / T228.1, the conductivity is tested according to the method of YS / T478, the softening temperature is tested according to the method of GB / T 33370, and the ablation performance is tested using the self-developed electric ablation device;

[0150] It can be seen from the results in Tables 2-3 above that the Cu-Cr-Nb-RE material guide rails prepared in Examples 1 to 3, compared with the Cu-Cr material guide rails prepared in Comparative Example 1, not only have high strength and high conductivity, but also have a high softening temperature and good comprehensive performance of high temperature ablation resistance, which significantly improves a series of problems existing in the current guide rails.

[0151] 3. Take the Cu-Cr-Nb-RE material guide rail samples prepared in Example 4 and Comparative Example 2 respectively, and test their performance. The test results are shown in Table 4 below;

[0152] Table 4 Cu-Cr-Nb-RE material guide rail performance test table

[0153]

[0154] It can be seen from the results in Table 4 above that the Cu-Cr-Nb-RE material guide rail prepared in Example 4 has higher strength and electrical conductivity, as well as a higher softening temperature and good comprehensive performance of high-temperature ablation resistance, compared with the Cu-Cr-Nb-RE material guide rail prepared in Comparative Example 2.

Claims

1. A method for manufacturing a Cu-Cr-Nb-RE material guide rail for an electromagnetic rail gun, characterized in that: The following steps are involved: S1. Prepare the blank: The raw materials are smelted to obtain a Cu-Cr-Nb-RE alloy ingot, the alloy ingot is powdered by vacuum electrode gas atomization to obtain a Cu-Cr-Nb-RE alloy powder, and the alloy powder is finally hot isostatically pressed to obtain a Cu-Cr-Nb-RE material; The raw materials include: 5.0-8.0wt% of chromium-niobium master alloy, 0.05-0.10wt% of rare earth element RE, and the balance is electrolytic copper plate; S2. Forging: Forging the material obtained in step S1 to obtain a forged square billet, wherein the forging temperature is 850-950° C., the temperature is kept for 80-150 minutes, and the deformation amount per forging is 30-50%; S3, primary annealing: Annealing the forged billet obtained in step S2 to obtain a primary annealed billet, wherein the annealing temperature is 600-800° C. and the temperature is kept for 1-4 hours; S4, rough rolling: The once annealed billet obtained in step S3 is subjected to rough rolling to obtain a rough rolled billet, wherein the rough rolling deformation is 60-90%; S5, secondary annealing: Annealing the rough rolled billet obtained in step S4 to obtain a secondary annealed billet, wherein the secondary annealing temperature is 600-800° C. and the temperature is kept for 1-4 hours; S6, medium rolling: The secondary annealed billet obtained in step S5 is subjected to intermediate rolling to obtain an intermediate rolled billet, wherein the intermediate rolling deformation is 50-80%; S7, machining: Machining the intermediate rolled billet obtained in step S6 to obtain a guide rail; In step S1, the smelting is vacuum induction melting, and the vacuum induction melting includes the following steps: S1-1. Melting: The electrolytic copper plate is added into a vacuum induction melting furnace, and after melting, the chromium-niobium master alloy is added, and heating and melting are continued. When the heating temperature rises to 1500-1700° C., rare earth element RE is added; S1-2, Refining: After all the raw materials in the crucible are melted, refine for 10-40 minutes; S1-3, pouring: Then, a Cu-Cr-Nb-RE material alloy ingot is cast; During refining in step S1-2, an adsorber is placed on the surface, and the adsorber is made of porous zirconia. The obtained alloy melt is cooled in situ on the crucible to obtain a solidified and cooled billet, the top of which is cut off, and the cut solidified and cooled billet is returned to the furnace for melting again; Before step S1-1, the vacuum induction melting furnace is preheated at a temperature of 700-900°C for 1-4 hours, and the vacuum degree is drawn to 10 -3 ~10 -1 Pa, and then introduce argon gas to 0.8~0.95×10 5 Pa, and evacuate to 10 -3 ~10 - 1 Pa; In step S1-1, the electrolytic copper plate and the chromium-niobium master alloy are melted respectively. The electrolytic copper plate is melted once, the melting temperature is 1080-1100°C, the melting time is 30-180 min, and during the melting, argon gas is filled into the vacuum chamber to 0.8-0.95×10 5 Pa, and evacuate to 10 -3 ~10 -1 Pa, when the melting amount of the electrolytic copper plate reaches 2 / 5~3 / 5 of the total amount, the heating power is reduced by 6~9kW, and argon is introduced into the melting electrolytic copper plate by bottom blowing at a flow rate of 0.5~0.8L / min to fully mix the argon with the electrolytic copper plate melt; The chromium-niobium master alloy is smelted twice. The first smelting temperature of the chromium-niobium master alloy is 1600-1700°C. When melting begins, argon gas is introduced into the melting chromium-niobium master alloy in a bottom blowing manner into the vacuum chamber. The argon gas flow rate is 0.1-0.4L / min. After smelting for 50-120min, the master alloy is cooled in situ. After cooling for 80-240min, the second smelting is started. The master alloy is vacuumized to 10 -3 ~10 -1 Pa, the second melting temperature of the chromium-niobium master alloy is 1550-1650°C, the melting time is 30-120min, and when the melting time is 15-60min, argon gas is introduced into the vacuum chamber by bottom blowing, and the argon gas flow rate is 0.8-1.2L / min to obtain a chromium-niobium master alloy liquid; Then, the chromium-niobium master alloy liquid after the second smelting is added to the electrolytic copper plate after the first smelting, and argon gas is introduced into the electrolytic copper plate by bottom blowing, and the argon gas flow rate is 1.5-1.9 L / min. When the heating temperature rises to 1500-1700°C, rare earth element RE is added, and argon gas with a flow rate of 2.5-2.9 L / min is introduced into the electrolytic copper plate again by bottom blowing, and heating and melting are continued; In step S1-1, during the process of introducing argon, ensure that the pressure in the vacuum induction melting furnace is ≤10 -1 Pa.

2. The method for manufacturing a Cu-Cr-Nb-RE material guide rail for an electromagnetic rail gun according to claim 1, characterized in that: The chromium-niobium master alloy contains 45-50 wt % niobium and the remainder is chromium. The electrolytic copper plate contains more than 99.97 wt % copper.

3. The method for manufacturing a Cu-Cr-Nb-RE material guide rail for an electromagnetic rail gun according to claim 1, characterized in that: In step S1, the cooling rate of the atomized powder is 10 2 -10 7 K / ℃, and the alloy powder particle size is less than 150μm.

4. The method for manufacturing a Cu-Cr-Nb-RE material guide rail for an electromagnetic rail gun according to claim 1, characterized in that: In step S1, the hot isostatic pressing temperature is 800-1000°C, the pressure is 100-200 MPa, and the time is 2-5 hours.

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