Titanium alloy consumable electrode preparation method capable of preventing gas elements from being mixed into raw materials

Abstract

The invention relates to a titanium alloy consumable electrode preparation method capable of preventing gas elements from being mixed into raw materials. The method comprises the following steps: a raw material transfer and storage stage: transferring raw materials to a corresponding stock bin for storage within a preset time; in the raw material mixing stage, the raw materials are transferred to a mixer through a conveying belt to be mixed, and an electromagnetic induction coil heating device is laid on the outer surface of the mixer; an electrode block pressing stage: transferring the uniformly mixed raw materials into a die cylinder for pressing the consumable electrode to press the consumable electrode block; in the pressing process, a heating cavity with micro-positive pressure atmosphere is formed in the mold cylinder, and the temperature in the heating cavity is kept through an electric heating device; and an electrode block welding stage, specifically, the pressed consumable electrode blocks are transferred into a vacuum welding box, the blocky consumable electrode blocks are welded into an integral electrode through plasma welding, and a high-purity titanium alloy cast ingot is obtained through multiple times of vacuum consumable smelting. The method ensures the purity of raw material gas elements.

Description

Technical Field

[0001] The invention relates to the technical field of titanium alloy electrode preparation, in particular to a method for preparing a titanium alloy consumable electrode which prevents gas elements from mixing into raw materials. Background Art

[0002] The first step in the preparation of titanium alloy materials is the preparation of titanium alloy electrodes. In the existing titanium alloy electrode preparation process at home and abroad, the conventional method is to mix the raw materials (sponge titanium, intermediate alloy, etc.) in an atmospheric environment by mechanized or manual stirring, and then send them into a hydraulic press to press them into electrode blocks. The pressed electrode blocks are then connected into a complete welded electrode by argon-shielded manual welding or vacuum plasma-shielded welding. Finally, the welded electrodes are sent to a vacuum consumable melting furnace for repeated remelting and purification to obtain titanium alloy ingots.

[0003] However, in actual use, due to the influence of uncontrollable factors such as atmospheric temperature and humidity (such as high temperature and high humidity in summer, low temperature and low humidity in winter, humid south and dry north, etc.), during the raw material mixing stage, electrode block preparation stage and electrode block welding stage, it is inevitable that sponge titanium and intermediate alloy will "absorb moisture", resulting in fluctuations in the content of gas elements (oxygen, nitrogen, hydrogen, etc.) in the finished titanium alloy ingot, which will lead to fluctuations in the performance of the final titanium alloy bars and forgings or even unqualified products. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the problem of fluctuation of gas element content that easily occurs when preparing high-purity titanium alloy ingots in the prior art.

[0005] To solve the above technical problems, the present invention provides a method for preparing a titanium alloy consumable electrode that prevents gas elements from mixing into raw materials, comprising: Step S1, raw material transfer and storage stage: providing raw materials, including sponge titanium and various master alloys, and transferring the raw materials from raw material sealed barrels to corresponding silos for storage within a predetermined time; wherein the silos use constant humidity silos; Step S2, raw material mixing stage: the raw materials are transferred from the conveyor belt to the mixer for mixing; wherein the outer surface of the mixer is provided with an electromagnetic induction coil heating device, which utilizes electromagnetic induction heating to dry the raw materials during the mixing process, thereby absorbing moisture while maintaining uniform mixing of the raw materials; Step S3, electrode block pressing stage: the uniformly mixed raw materials are transferred to a mold barrel for pressing the consumable electrode to press the consumable electrode block; wherein, during the pressing process, a heating cavity with a slightly positive pressure atmosphere is provided in the mold barrel, the temperature inside the heating cavity is maintained by an electric heating device, and dry gas is introduced through an automatically controlled valve at the bottom edge of the mold barrel to form a slightly positive pressure atmosphere. The positive pressure atmosphere is formed before the electrode punch contacts the raw materials, thereby preventing the intrusion of gas elements from the raw materials at different positions of the consumable electrode block during the pressing process; Step S4, electrode block welding stage: the pressed consumable electrode blocks are transferred to a vacuum welding box, the consumable electrode blocks are welded into integral electrodes by plasma welding, and high-purity titanium alloy ingots are obtained through multiple vacuum consumable melting.

[0006] In one embodiment of the present invention, in step S1, the transfer time of the raw materials does not exceed 3 hours; wherein, the silo is a constant humidity closed structure, and the silo is equipped with an industrial automatic dehumidifier to achieve humidity control.

[0007] In one embodiment of the present invention, in step S1, the humidity in the silo is maintained at no more than 30%.

[0008] In one embodiment of the present invention, in step S2, the electromagnetic induction coil heating device uses a water-cooled multi-turn solenoid electromagnetic induction coil, uses alternating current for heating, and the induction coil power is 200kW~300kW and the frequency is 10kHz~20kHz.

[0009] In one embodiment of the present invention, in step S2, the mixer heats the surface of the raw materials by the skin effect of electromagnetic induction while the raw materials are being mixed uniformly, and the surface temperature of the raw materials is controlled between 100°C and 200°C.

[0010] In one embodiment of the present invention, in step S3, the temperature inside the heating chamber is maintained at 200°C to 300°C; the pressure difference of the slightly positive pressure atmosphere is in the range of 30Pa to 80Pa; the flow rate of the drying gas is ≥500m 3 / h.

[0011] In one embodiment of the present invention, in step S4, the plasma welding process parameters are: welding current of 450A~550A, welding voltage of 40V~80V, welding speed of 50mm / min~100mm / min, filling argon pressure of 20kPa~30kPa, argon flow rate of 20L / min~40L / min; cooling time after welding is 120min~180min.

[0012] In one embodiment of the present invention, in step S4, the time for transferring the welded integral electrode from the vacuum welding box to the vacuum consumable arc furnace does not exceed 30 minutes.

[0013] The above technical solution of the present invention has the following advantages over the prior art: The present invention provides a method for preparing a titanium alloy consumable electrode that prevents gas elements from mixing into raw materials. The method strictly controls the absorption of gas elements through various means during the processes of raw material storage, raw material mixing, and electrode block pressing, thereby ensuring the purity of the gas elements in the raw materials.

[0014] During the raw material transfer and storage stage, the present invention transfers the opened barrels of titanium sponge and master alloys to the titanium sponge and master alloy silos for storage using a transport mechanism after magnetic and color sorting by an automatic material sorting machine. The time from barrel opening to transfer of the raw materials to the silos for storage does not exceed 3 hours. All raw material silos are closed structures, and an industrial automatic dehumidifier is installed on the outer wall of the silo to control the humidity of the silos. The humidity of the raw material silos is controlled to no more than 30%. Compared with the traditional method of selecting and transporting the raw materials to the silo after opening the barrels and storing them in the atmosphere for a long time, this method avoids the problem of "moisture" caused by the raw materials coming into contact with the atmosphere, and ensures the purity of the raw materials.

[0015] In the raw material mixing stage of the present invention, after the raw materials (sponge titanium, intermediate alloy) are transferred from the conveyor belt to the mixer, an electromagnetic induction coil heating and drying device is laid on the outer surface of the mixer. After the raw materials are sent to the mixer by the lifting mechanism, the mixer is automatically powered on and, under the action of electromagnetic induction, heat is generated on the surface of the raw materials due to the "skin effect", drying any "water vapor" that may exist on the surface of the raw materials. At the same time, the mixer continuously rotates to fully mix all the raw materials.

[0016] In the electrode block pressing stage of the present invention, the evenly mixed raw materials are transferred to the mold barrel for pressing the electrode block for electrode pressing. During the electrode pressing process, the valve automatically controlled by the bottom edge of the mold barrel controls the micro-airflow and the electrode punch to form a micro-positive pressure atmosphere in the cavity, and the temperature inside the cavity is maintained at 200°C~300°C. Before the electrode punch contacts the raw materials, the positive pressure atmosphere is formed, so that the humid gas in the environment cannot enter the cavity, thereby avoiding the invasion of gas elements of the raw materials at different positions from the inside to the outside of the pressed electrode block, thereby solving the problem of fluctuation of gas elements in the consumable electrode block caused by "moisture" adsorbed on the surface of the raw materials.

[0017] In the electrode block welding stage, the present invention transfers the pressed consumable electrode block into a vacuum welding box, and welds the block-shaped consumable electrode block into an integral electrode through vacuum plasma welding. The cooling time after welding is 120 minutes to 180 minutes, and the time for transferring the welded integral electrode from the vacuum welding box to the vacuum consumable arc furnace does not exceed 30 minutes, thereby avoiding the problem of the integral electrode being affected by moisture during the transfer process. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings.

[0019] Figure 1 This is a flow chart of a method for preparing a titanium alloy consumable electrode that prevents gas elements from mixing into raw materials according to Example 1 of the present invention.

[0020] Figure 2 Schematic diagram of the structure of the mixer of Example 1 of the present invention. DETAILED DESCRIPTION

[0021] The present invention will be further described below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. However, the embodiments are not intended to limit the present invention.

[0022] In the present invention, "several" means one or more, "multiple" means more than two, "greater than," "less than," "exceeds," etc. are understood to exclude the number itself; "above," "below," "within," etc. are understood to include the number itself. In the description of the present invention, the use of "first" or "second" is solely for the purpose of distinguishing technical features and is not to be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0023] Example 1 Reference Figure 1 As shown, a method for preparing a titanium alloy consumable electrode in this embodiment to prevent gas elements from mixing into raw materials includes: Step S1, raw material transfer and storage stage: providing raw materials, including sponge titanium and various master alloys, and transferring the raw materials from the raw material sealed barrel to the corresponding silo for storage within a predetermined time; wherein, the silo adopts a constant humidity silo to avoid air absorption of the raw materials.

[0024] Step S2, raw material mixing stage: the raw materials are transferred from the conveyor belt to the mixer for mixing; wherein, the outer surface of the mixer is provided with an electromagnetic induction coil heating device, and the electromagnetic induction coil heating device uses electromagnetic induction heating to dry the raw materials during the mixing process, thereby preventing the raw materials from absorbing moisture while maintaining uniform mixing of the raw materials.

[0025] Reference Figure 2 As shown, the mixer includes a shell with a pouring port. An electromagnetic induction coil is laid on the outer surface of the shell, and the electromagnetic induction coil is driven to rotate by a rotating roller installed on the shell to achieve mixing.

[0026] Step S3, electrode block pressing stage: The evenly mixed raw materials are transferred to a mold barrel for pressing the consumable electrode to press the consumable electrode block; wherein, during the pressing process, a heating cavity with a slightly positive pressure atmosphere is provided in the mold barrel, the temperature inside the heating cavity is maintained by an electric heating device, and dry gas is introduced through a valve automatically controlled by the bottom edge of the mold barrel to form a slightly positive pressure atmosphere. The positive pressure atmosphere is formed before the electrode punch contacts the raw materials, thereby preventing the intrusion of gas elements from the raw materials at different positions of the consumable electrode block during the pressing process. That is, the humid gas in the environment cannot enter the heating cavity, thereby avoiding the problem of gas element fluctuations in the consumable electrode block caused by the adsorption of gas elements on the surface of the raw materials due to high environmental humidity during the electrode pressing process.

[0027] For example, the die cylinder for pressing the consumable electrode may adopt a 120MN press (model: THP120) and a matching die cylinder produced by Tianjin Forging Equipment Co., Ltd.

[0028] Step S4, electrode block welding stage: the pressed consumable electrode blocks are transferred to a vacuum welding box, the consumable electrode blocks are welded into integral electrodes by plasma welding, and high-purity titanium alloy ingots are obtained through multiple vacuum consumable melting.

[0029] It should be noted that the applicant discovered that, in the prior art, the titanium sponge silo, filled with inert argon gas, effectively prevented moisture absorption when the raw materials were sealed. However, once the lid was removed, the titanium sponge's surface, due to its porous, sponge-like structure, readily absorbed moisture in the atmosphere (particularly in the humid summer air of southern China), leading to an increase in the raw material's gaseous element (oxygen, nitrogen, and hydrogen) content. To prevent moisture absorption during use, existing procedures generally require that the titanium sponge be used within a certain timeframe (≤12 hours) after opening, minimizing its exposure to air. However, due to equipment failures or sudden changes in temperature and humidity, the time the titanium sponge remains exposed to air after opening cannot be effectively controlled within this range, resulting in surface moisture and an abnormal increase in gaseous element content.

[0030] At the same time, in the raw material mixing and electrode block pressing stages, the current titanium alloy raw material mixing and pressing process mainly adopts the method of sending the raw materials used for a single electrode into a mixer through a transportation mechanism, and then using an open or closed rotary mixer to mix the raw materials evenly, and then sending them into a mold barrel to be pressed into an electrode block; however, since the raw materials are inevitably in contact with equipment exposed to the air during each blanking, mixing, transfer, and pressing process, especially in the rainy season in southern my country, the surface of the equipment is often humid, which will cause the raw materials to absorb moisture; to address this problem, the applicant has tried technical improvements, such as changing the time for opening the cover to pick the raw materials, mixing the materials, and pressing the electrodes, so as to avoid the influence of the relatively high atmospheric humidity on the "moisture absorption" of the raw materials in the morning and evening every day, so as to obtain high-purity titanium alloy electrode blocks, but through actual operation, the improvement effect on the purity of the electrode blocks and the stability of the gas elements is still not particularly obvious.

[0031] Specifically, in step S1, the titanium sponge is transferred from a titanium sponge barrel to a titanium sponge silo for storage, and the master alloy is transferred from a master alloy barrel to a master alloy silo for storage. The transfer time of the raw materials does not exceed 3 hours. The silo is a closed structure with a constant humidity and is equipped with an industrial automatic dehumidifier to achieve humidity control. In addition, in step S1, the humidity in the silo is maintained at no more than 30%.

[0032] Through step S1 of this embodiment, during the raw material transfer and storage stage, the opened barrels of titanium sponge and master alloys are subjected to magnetic and color sorting by an automatic material sorting machine, and then a transportation mechanism is used to transfer the raw materials to the titanium sponge and master alloy silos for storage. The time from the opening of the barrel to the transfer to the silo for storage does not exceed 3 hours. All raw material silos are closed structures, and an industrial automatic dehumidifier is installed on the outer wall of the silo to control the humidity of the silo. The humidity of the raw material silo is controlled to no more than 30%. Compared with the traditional method of selecting and transporting the raw materials to the silo after opening the barrel and storing them in the atmospheric environment for a long time, this method avoids the problem of "moisture" caused by the raw materials coming into contact with the atmosphere, thereby ensuring the purity of the raw materials.

[0033] Specifically, in step S2, the electromagnetic induction coil heating device adopts a water-cooled multi-turn solenoid electromagnetic induction coil, adopts alternating current for heating, the induction coil power is 200kW~300kW, and the frequency is 10kHz~20kHz.

[0034] Specifically, in step S2, while the raw materials are being mixed uniformly, the mixer heats the surface of the raw materials through the skin effect of electromagnetic induction, and the surface temperature of the raw materials is controlled between 100°C and 200°C.

[0035] Through step S2 of this embodiment, in the raw material mixing stage, after the raw materials (sponge titanium, intermediate alloy) are transferred from the conveyor belt to the mixer, an electromagnetic induction coil heating and drying device is laid on the outer surface of the mixer. After the raw materials are sent to the mixer by the lifting mechanism, the mixer is automatically powered on and, under the action of electromagnetic induction, heat is generated on the surface of the raw materials due to the "skin effect", drying any "water vapor" that may exist on the surface of the raw materials. At the same time, the mixer continuously rotates to fully mix all the raw materials.

[0036] It should be noted that the skin effect refers to the phenomenon in which, when an alternating current flows through a conductor or an alternating magnetic field acts on it, the induced current is primarily concentrated on the conductor's surface. The closer to the surface, the greater the current density, and it decays rapidly with depth. This current distribution phenomenon generates strong Joule heating near the conductor's surface, thus achieving surface heating. By installing an electromagnetic induction coil on the outer surface of the mixer and applying medium-high frequency (10kHz-20kHz) alternating current, a strong alternating magnetic field is generated around the coil. The raw materials (titanium sponge and master alloy) inside the mixer are good conductors, and the alternating magnetic field induces eddy currents on the surface of the particles. Due to the skin effect, these eddy currents are primarily concentrated within a 2-3 mm thickness on the surface of each metal particle. As the eddy currents flow along the metal surface, they are dissipated as heat energy (Joule heating) due to the metal's inherent electrical resistance, causing the raw material surface to rapidly heat up. The heat generated by skin heating is primarily distributed on the surface of the metal particles, effectively heating and evaporating any moisture, gas, or impurities adhering to the particle surface. During heating, the mixer rotates and mixes, ensuring that each particle's surface is evenly exposed to the magnetic field, ensuring consistent drying results. Because heat is concentrated on the raw material surface, it prevents overall overheating and energy waste. The enclosed mixing environment eliminates the need for external heat sources or hot air, reducing contamination risks and facilitating automated control.

[0037] Specifically, in step S3, the temperature inside the heating chamber is maintained at 200°C to 300°C; the pressure difference of the slightly positive pressure atmosphere is in the range of 30Pa to 80Pa; the flow rate of the drying gas is ≥500m 3 / h.

[0038] Through step S3 of this embodiment, in the electrode block pressing stage, the evenly mixed raw materials are transferred to the mold barrel for pressing the electrode block for electrode pressing. During the electrode pressing process, the valve automatically controlled by the bottom edge of the mold barrel controls the micro-airflow and the electrode punch to form a micro-positive pressure atmosphere in the cavity, and the temperature inside the cavity is maintained at 200℃~300℃. Before the electrode punch contacts the raw material, the micro-positive pressure atmosphere is formed, so that the humid gas in the environment cannot enter the cavity, avoiding the invasion of gas elements of the raw materials from different positions from the inside to the outside of the pressed electrode block, thereby solving the problem of fluctuation of gas elements in the consumable electrode block caused by "moisture" adsorbed on the surface of the raw materials.

[0039] Specifically, in step S4, the plasma welding process parameters are: welding current of 450A~550A, welding voltage of 40V~80V, welding speed of 50mm / min~100mm / min, filling argon pressure of 20kPa~30kPa, argon flow rate of 20L / min~40L / min; cooling time after welding is 120min~180min.

[0040] Specifically, in step S4, the time for transferring the welded integral electrode from the vacuum welding box to the vacuum consumable arc furnace does not exceed 30 minutes.

[0041] Through step S4 of this embodiment, during the electrode block welding stage, the pressed consumable electrode block is transferred to a vacuum welding box, and the block-shaped consumable electrode block is welded into an integral electrode by vacuum plasma welding. The post-weld cooling time is 120 minutes to 180 minutes, and the time for transferring the welded integral electrode from the vacuum welding box to the vacuum consumable arc furnace does not exceed 30 minutes, thereby avoiding the problem of the integral electrode being affected by moisture during the transfer process.

[0042] Example 2 This embodiment provides a method for preparing a titanium alloy consumable electrode that prevents gas elements from mixing into raw materials. Specifically, taking the preparation and ingot melting of TC4 electrodes, which are the most common in industrial production, as an example, the method includes the following steps: Step S1: During the storage phase of TC4, raw materials (grade 0 titanium sponge, Al-55V alloy, aluminum beans, ferro-titanium alloy, and titanium dioxide) are transferred from titanium sponge barrels and master alloy barrels to corresponding silos. A constant humidity silo is used to prevent the raw materials from inhaling air. The time from opening the barrel to transferring the raw materials into the silo is 1 hour. The constant humidity silo is an automatically closed structure, and an industrial automatic dehumidifier is installed on the outer wall of the silo to control the humidity of the silo. The humidity of the silo corresponding to all raw materials is controlled at 20% to 30%. The raw materials are automatically weighed and discharged according to the set ratio.

[0043] Step S2: After the raw materials for the single electrode (sponge titanium, intermediate alloy, weighing 150-200 kg) are transferred from the conveyor belt to the mixer, all the raw materials are heated and dried using an electromagnetic induction coil laid on the outer surface of the mixer. The electromagnetic induction coil heating device uses alternating current heating of a water-cooled multi-turn solenoid coil, with an induction coil power of 200 kW and a frequency of 15 kHz; the surface temperature of the raw materials is detected by an infrared temperature measuring gun and is controlled at 100-200°C; the mixer described in step S2 is used to heat the surface of the raw materials by the skin effect of electromagnetic induction while the raw materials are uniformly mixed.

[0044] Step S3: Transfer the mixed raw materials to the mold barrel for pressing the consumable electrode for electrode pressing. The mold barrel is electrically heated to maintain the internal temperature of the cavity at 200°C to 300°C. In addition, the mold barrel controls the micro-airflow and the electrode punch through the valve automatically controlled at the bottom edge to form a slightly positive pressure atmosphere in the cavity. The mold barrel controls the micro-airflow and the electrode punch through the valve automatically controlled at the bottom edge to form a slightly positive pressure atmosphere in the raw material cavity. The positive pressure difference is controlled between 40Pa and 50Pa, and the flow rate of the drying gas is controlled at 500m 3 / h~600m 3 / h, so that the humid gas in the environment cannot enter the cavity, thereby avoiding the problem of gas elements enriched on the surface of raw materials due to high humidity in the environment during the electrode pressing process.

[0045] Step S4, transferring the pressed consumable electrode block to a vacuum welding box, and welding the block-shaped consumable electrode block into an integral electrode by plasma welding; the welding current of the TC4 consumable electrode block is 450A, the welding voltage is 60V, the welding speed is 100mm / min, the filling argon pressure is 30kPa, the argon flow rate is 40L / min, the post-weld cooling time is 180min, and the time for transferring the welded integral electrode from the vacuum welding box to the vacuum consumable arc furnace is 20min. After being transferred to the vacuum consumable melting furnace, three vacuum consumable meltings are performed to obtain a high-purity TC4 titanium alloy ingot.

[0046] The following table compares the composition of TC4 ingots produced by different electrode preparation processes. It can be seen that the Al and V content of the electrode prepared in this embodiment fluctuates by 0.02% and 0 at the beginning and end, respectively, which are lower than the 0.13% and 0.03% of the conventional process. Therefore, this embodiment has improved composition uniformity compared to the existing process. In addition, the iron (Fe) content of this embodiment is 0.19% at both the beginning and end, and the composition stability is better than that of the conventional process (0.20% and 0.17%). The content of gas elements (oxygen, nitrogen, and hydrogen) is a key impurity element that affects the purity of titanium alloys. In this embodiment, the oxygen element is 0.031% and 0.027% at the beginning and end, respectively, which is significantly lower than the 0.052% and 0.048% of the conventional process, a decrease of about 40%. In addition, the nitrogen (N) and hydrogen (H) contents of this embodiment are 0.0015% and 0.0002% at the head and 0.0018% and 0.0002% at the tail, respectively. Compared with the conventional process (N is 0.0032% and 0.0035%, and H is 0.0004% and 0.0005%), the nitrogen (N) and hydrogen (H) impurity contents are reduced by about 50%.

[0047] Therefore, the preparation process of this embodiment is much better than the conventional preparation process in controlling the purity of impurity elements.

[0048] Table 1. Comparison of TC4 ingot composition using different electrode preparation processes

[0049] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for preparing a titanium alloy consumable electrode that prevents gas elements from mixing into raw materials, characterized in that: include: Step S1, raw material transfer and storage stage: providing raw materials, including sponge titanium and various master alloys, and transferring the raw materials from raw material sealed barrels to corresponding silos for storage within a predetermined time; wherein the silos use constant humidity silos; Step S2, raw material mixing stage: the raw materials are transferred from the conveyor belt to the mixer for mixing; wherein, the outer surface of the mixer is provided with an electromagnetic induction coil heating device, which utilizes the electromagnetic induction principle to dry the raw materials during the mixing process, thereby maintaining uniform mixing of the raw materials and preventing them from absorbing moisture; Step S3, electrode block pressing stage: the uniformly mixed raw materials are transferred to a mold barrel for pressing the consumable electrode to press the consumable electrode block; wherein, during the pressing process, a heating cavity with a slightly positive pressure atmosphere is provided in the mold barrel, the temperature inside the heating cavity is maintained by an electric heating device, and dry gas is introduced through an automatically controlled valve at the bottom edge of the mold barrel to form a slightly positive pressure atmosphere. The positive pressure atmosphere is formed before the electrode punch contacts the raw materials, thereby preventing the intrusion of gas elements from the raw materials at different positions of the consumable electrode block during the pressing process; Step S4, electrode block welding stage: the pressed consumable electrode blocks are transferred to a vacuum welding box, the consumable electrode blocks are welded into integral electrodes by plasma welding, and high-purity titanium alloy ingots are obtained through multiple vacuum consumable melting.

2. The method for preparing a titanium alloy consumable electrode that prevents gas elements from mixing into raw materials according to claim 1, characterized in that: In step S1, the transfer time of the raw materials does not exceed 3 hours; wherein, the silo is a constant humidity closed structure, and the silo is equipped with an industrial automatic dehumidifier to achieve humidity control.

3. The method for preparing a titanium alloy consumable electrode that prevents gas elements from mixing into raw materials according to claim 1, characterized in that: In step S1, the humidity in the silo is maintained at no more than 30%.

4. The method for preparing a titanium alloy consumable electrode that prevents gas elements from mixing into raw materials according to claim 1, characterized in that: In step S2, the electromagnetic induction coil heating device uses a water-cooled multi-turn solenoid electromagnetic induction coil and uses alternating current for heating. The induction coil power is 200kW~300kW and the frequency is 10kHz~20kHz.

5. The method for preparing a titanium alloy consumable electrode that prevents gas elements from mixing into raw materials according to claim 1, characterized in that: In step S2, while the raw materials are being mixed uniformly, the mixer heats the surface of the raw materials through the skin effect of electromagnetic induction, and the surface temperature of the raw materials is controlled between 100°C and 200°C.

6. The method for preparing a titanium alloy consumable electrode that prevents gas elements from mixing into raw materials according to claim 1, characterized in that: In step S3, the temperature inside the heating chamber is maintained at 200°C to 300°C; the pressure difference of the slightly positive pressure atmosphere is in the range of 30Pa to 80Pa; the flow rate of the drying gas is ≥500m 3 / h.

7. The method for preparing a titanium alloy consumable electrode that prevents gas elements from mixing into raw materials according to claim 1, characterized in that: In step S4, the plasma welding process parameters are: welding current of 450A~550A, welding voltage of 40V~80V, welding speed of 50mm / min~100mm / min, filling argon pressure of 20kPa~30kPa, argon flow rate of 20L / min~40L / min; cooling time after welding is 120min~180min.

8. The method for preparing a titanium alloy consumable electrode that prevents gas elements from mixing into raw materials according to claim 1, characterized in that: In step S4, the time for transferring the welded integral electrode from the vacuum welding box to the vacuum consumable arc furnace does not exceed 30 minutes.

Images