A high-uniformity titanium alloy electrode block pressing method

Abstract

This invention relates to the field of titanium alloy consumable electrode preparation, and specifically discloses a method for pressing titanium alloy electrode blocks with high uniformity. This method improves the uniformity of the distribution of each component of the titanium alloy electrode block and the bottom density by rotating and reversing the feeding process and applying ultrasonic vibration during a specific time period in the pressing stage, and significantly reduces the raw material loss in the electrode block forming process.

Description

Technical Field

[0001] This invention relates to the field of titanium alloy ingot consumable electrode preparation technology, specifically to a method for pressing highly uniform titanium alloy electrode blocks for vacuum consumable melting. Background Technology

[0002] The preparation of high-end titanium alloy ingots typically employs a vacuum consumable arc melting method. Before melting, sponge titanium and master alloys need to be pressed into shape and assembled into consumable electrodes. In the actual production process, the consumable electrodes are usually made by mixing sponge titanium with master alloys and other raw materials, pressing them into electrode blocks, and then welding these electrode blocks together to form an electrode. The uniformity and density of the electrode blocks not only affect the safety and stability of subsequent melting processes but also directly influence the uniformity and stability of the composition of the finished ingot.

[0003] To achieve relatively uniform alloying, some high-melting-point or easily segregated master alloys need to be added in powder or small particle form to facilitate rapid dissolution and diffusion during the smelting process. Therefore, the mixture during the pressing process often contains components with different particle sizes and packing characteristics, such as sponge titanium, large-particle master alloys, and powder or small-particle master alloys. Due to the small particle size and high flowability of powder or small-particle master alloys, the mixture is prone to stratification and deposition under gravity and equipment vibration or shaking during mixing in the mixer, transfer to the feeding hopper, and conveying to the top of the mold cavity. This makes the powder or smaller-particle components more likely to accumulate downwards. When using conventional feeding methods, the powder or smaller-particle components tend to preferentially enter the bottom of the mold cavity and form a localized enrichment layer. During smelting, elements enriched at the bottom of the electrode block may have difficulty diffusing effectively, leading to severe localized segregation in the finished ingot. In addition, the segregation of some intermediate alloys at the bottom of the mold cavity can lead to inconsistent compaction and bonding in the bottom area of ​​the electrode block, resulting in problems such as local porosity and insufficient strength. It may also cause raw material loss in demolding, pushing, and transfer processes, ultimately affecting the compositional uniformity and stability of the finished ingot.

[0004] To address the aforementioned issues of mixture stratification, powder sedimentation and enrichment, and insufficient uniformity in bottom forming, existing technologies have proposed improvements such as layered feeding, floating pressing, powder pre-pressing, and sponge titanium underlayment. However, these improvements may still suffer from drawbacks in practical applications, including high process complexity, significant equipment modification requirements, limited adaptability, or effectiveness affected by material conditions and operating fluctuations. Therefore, there is an urgent need to develop a method that can effectively improve the distribution of the mixture in the mold and enhance the uniformity and density of the pressed electrode blocks during the electrode block forming process, thereby reducing material loss during forming and improving the stability of the pressing process. Summary of the Invention

[0005] To address the shortcomings of the existing technology, the purpose of this invention is to provide a method for pressing titanium alloy electrode blocks with high uniformity. By improving the key steps in the electrode block forming process, this method solves the problems in the existing technology, such as powder settling and enrichment at the bottom of the mixture during the feeding process, poor uniformity of the components of the electrode block, and insufficient density in the bottom area. This effectively improves the uniformity and density of the electrode block, reduces material loss in the forming process, and enhances the stability of the titanium alloy ingot production process.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A method for pressing highly uniform titanium alloy electrode blocks is characterized by the following process: raw materials are mixed and fed into a feeding hopper, which is then conveyed to the top of the pressing mold cavity with the hopper's inlet facing upwards, outlet facing downwards, and outlet valve closed. The feeding hopper is then rotated so that its inlet faces downwards and is positioned above the pressing mold cavity, allowing material to be discharged from the inlet into the cavity. After discharge, the mixture in the cavity is pressed. During the pressing stage, when the pressure head is pressed down to 1.2-1.5 times the preset height of the electrode block, ultrasonic vibration is applied to the bottom of the pressing mold cavity.

[0007] Preferably, the rotation speed of the feeding hopper is controlled to be 2° / s-8° / s.

[0008] Preferably, the parameters for the ultrasound and compression are: ultrasound frequency 20kHz, power 1500W, action time 10-15 seconds, and compression pressure 35-65MN.

[0009] The above-mentioned method for pressing highly uniform titanium alloy electrode blocks is implemented through the following steps: Step 1) Raw material preparation: Take out sponge titanium and intermediate alloy according to the predetermined mass ratio, and sort the sponge titanium and intermediate alloy on the sorting machine to remove unqualified raw materials; Step 2) Batching and reweighing: Transfer the selected sponge titanium and intermediate alloy into the corresponding bins. Calculate and set the single-discharge weight of each bin based on the weight of a single electrode and the composition ratio. After the discharging is completed, transport the materials to the reweighing bin for reweighing. Step 3) Mixing: Rotate and stir the weighed mixture at a speed of 12-14 rpm for 0.5-2 minutes. Step 4) Rotary feeding: Transfer the mixture into the feeding hopper and use a linear guide to transport the feeding hopper to the top of the pressing mold cavity. When feeding, drive the feeding hopper to slowly rotate 140°-170° around the horizontal axis at a speed of 2° / s-8° / s, so that the feeding port of the feeding hopper slowly rotates to the top of the mold cavity and feeds the material into the mold cavity from the feeding port. Step 5) Ultrasonic Assisted Pressing: The mixture in the mold cavity is pressed. During the pressing stage, when the press head is pressed down to 1.2-1.5 times the preset height of the electrode block, ultrasonic vibration is applied to the bottom of the pressing mold. The ultrasonic and pressing parameters are controlled as follows: ultrasonic frequency 20kHz, power 1500W, action time 10-15 seconds, pressing pressure 35-65MN. The final pressed electrode block density is 3.2g / cm³-3.6g / cm³, and the pressing height is 180-200mm.

[0010] Compared with the prior art, the innovative points and beneficial effects of this invention are as follows: 1. Under the combined effects of centrifugal force and gravity, the mixture, even after thorough mixing in the mixer, still exhibits stratification. Furthermore, the impact of the material being fed into the hopper further exacerbates this stratification. This invention utilizes the naturally occurring "coarse at the top, fine at the bottom" gradient distribution of the mixture within the hopper. By precisely controlling the hopper's rotation angle and speed, the spatial order in which materials enter the mold cavity is actively constructed. This allows sponge titanium to preferentially enter the mold cavity to form a skeleton, while powdered or small-particle intermediate alloys enter later and fill the gaps between the sponge titanium particles under gravity. This prevents powder from directly concentrating and depositing at the bottom of the mold cavity, thereby improving the uniformity of material distribution within the mold cavity. The rotation angle and speed are key factors affecting the uniformity of material distribution within the mold cavity. If the rotation speed is inappropriate, the finer material at the bottom may be thrown out and hit the bottom again, damaging the existing layered structure (too fast rotation speed), or it may not have practical production application value (too slow rotation speed). If the rotation angle is too small, the material may not fall into the mold cavity completely, resulting in raw material loss and affecting the ingot composition. If it is too large, the initial velocity of the material leaving the feed port will be too high, and it will layer again due to impact when it hits the bottom of the mold cavity. After many experiments, the inventors finally determined that when the rotation speed is 2° / s-8° / s and the rotation angle is 140°-170°, the larger and fluffy sponge titanium particles at the top of the hopper can fall into the mold cavity relatively preferentially and smoothly, thereby constructing a three-dimensional skeleton network with a large number of internal gaps, so that the subsequent powder or small particle intermediate alloy can uniformly fill the gaps of the sponge titanium. 2. This invention uses ultrasonic-assisted electrode block pressing and molding, and creatively selects to apply the ultrasonic waves at the bottom of the mold when the pressure head is pressed down to 1.2-1.5 times the preset height of the electrode block. This timing is the optimal plastic deformation window period when the material has been initially compacted but there is still room for adjustment between particles. Applying ultrasonic waves at this time has a dual effect: on the one hand, the fine particles that have been initially filled in the sponge titanium skeleton undergo micro-fluidization and secondary rearrangement, further filling the residual pores and greatly improving the overall density and uniformity of the bottom of the electrode block; on the other hand, for the powder layer that may still remain at the bottom after rotating and feeding, the ultrasonic waves can make it move relative to the material that has formed the skeleton above, promoting mutual interlocking, thereby transforming the potential "fragile interlayer" into an organic component of the entire electrode block. In specific experiments, the inventors discovered that if ultrasound is applied in the early stage of pressing (before the press head is pressed down to 1.2-1.5 times the preset height of the electrode block), the energy is dispersed, the effect on the bottom is weak, and a large amount of powder is shaken off, which aggravates the stratification phenomenon. However, if ultrasound is applied in the later stage of pressing (after the press head is pressed down to 1.2-1.5 times the preset height of the electrode block), the effect of ultrasound is very small. This may be related to the fact that the particles are already tightly interlocked, and ultrasound is difficult to promote rearrangement. 3. The rotary feeding step and the ultrasonic-assisted pressing step of this invention are effectively combined to form a tightly integrated and functionally cohesive process chain. Rotary feeding creates optimized initial material distribution conditions for ultrasonic-assisted pressing, ensuring efficient and uniform utilization of ultrasonic energy, rather than it being dissipated or isolated by a severely segregated powder layer. Ultrasonic-assisted pressing, in turn, complements rotary feeding, further improving the uniformity and density of the electrode blocks. These two processes work synergistically, not only achieving uniform distribution of components but also reducing raw material loss in the molding process by an order of magnitude (from tens of grams in conventional processes to several grams). Attached Figure Description

[0011] Figure 1 This is a physical image of the bottom of the TC18 electrode block pressed according to Embodiment 1 of the present invention; Figure 2 This is a physical image of the bottom of the TC4 electrode block pressed according to Embodiment 2 of the present invention; Figure 3 This is a physical image of the bottom of the TC18 electrode block pressed according to Comparative Example 1 of the present invention; Figure 4 This is a physical image of the bottom of the TC4 electrode block pressed in Comparative Example 2 of the present invention; Figure 5 This is a physical image of the bottom of the TC18 electrode block pressed according to the comparative example of the present invention. Detailed Implementation

[0012] The present invention will be further described below with reference to specific embodiments and examples. Those skilled in the art should understand that these specific embodiments and examples are for illustrative purposes only and not for limiting the invention. Throughout this specification, unless otherwise specified, the terminology used herein should be understood as having the meaning commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. In case of any conflict, this specification shall prevail. Unless otherwise specified, all raw materials, instruments, and equipment used in this invention can be purchased commercially or prepared by existing methods.

[0013] This invention provides a method for pressing highly uniform titanium alloy electrode blocks. By optimizing key steps in the electrode block forming process, it achieves the preparation of electrode blocks with high uniformity, high density, and low material loss. Specifically, it includes the following steps: 1) Raw material preparation: Sponge titanium and intermediate alloy are requisitioned according to the predetermined quality ratio, and the sponge titanium and intermediate alloy are sorted on the sorting machine to remove unqualified raw materials; 2) Batching and re-weighing: Transfer the selected sponge titanium and intermediate alloy into the corresponding bins. Calculate and set the single-time feeding weight of each bin based on the weight of a single electrode and the composition ratio. After completion, transport the materials to the re-weighing bin via belt for weighing. 3) Mixing: The mixture is conveyed from the weighing hopper to the mixer for rotary stirring at a speed of 12-14 rpm for 0.5-2 minutes. Based on the above mixing parameters, the powder material can adhere well to the pores, surface, and gaps of the titanium sponge; however, a considerable portion of the powder or small-particle intermediate alloy will still deposit at the bottom due to gravity and centrifugal force during mixing. 4) Rotary feeding: The mixture obtained in step 3) is transferred into the feeding hopper, and the feeding hopper is transported to the top of the mold cavity of the pressing die using a linear guide rail; during feeding, the feeding hopper is driven to rotate slowly around the horizontal axis 140°-170° at a speed of 2° / s-8° / s, so that the feed inlet of the feeding hopper slowly rotates to the top of the mold cavity, and the material is fed into the mold cavity from the feed inlet (reverse feeding). Taking advantage of the state of the mixture in the feeding hopper where "powder and small-particle intermediate alloys are easy to deposit, and sponge titanium and large-particle intermediate alloys are relatively located at the top", the sponge titanium enters the mold cavity relatively first to form a skeleton, and the powder / fine-particle intermediate alloys enter relatively later and fill the gaps of the sponge titanium under the action of gravity, thereby improving the uniformity of material spatial distribution in the mold cavity and reducing the tendency of powder enrichment at the bottom; 5) Ultrasonic-assisted pressing: The mixture in the mold cavity is pressed. During the pressing stage, when the press head is pressed down to 1.2-1.5 times the preset height of the electrode block, ultrasonic vibration is applied to the bottom of the pressing mold. The ultrasonic and pressing parameters are controlled as follows: ultrasonic frequency 20kHz, power 1500W, action time 10-15 seconds, and pressing pressure 35-65MN; the final electrode block density is 3.2g / cm³-3.6g / cm³, and the pressing height is 180-200mm.

[0014] Through the above-described process steps, this invention achieves a synergistic improvement in the electrode block forming process through "optimized mold distribution and enhanced densification," resulting in titanium alloy electrode blocks with good uniformity, high density, and low material loss. The technical solution of this application will be further described below with reference to embodiments.

[0015] Example 1 (Rotational reverse feeding + ultrasonic-assisted molding and pressing of φ420 / 2mm TC18 electrode block) 1. Use intermediate alloys such as Al (particle size 8-13mm), Al-MO-V (particle size 0.1-3mm), Cr (particle size 0.5-3mm), Al-V (particle size 1-6mm), and Al-Fe (particle size 0.25-6mm) in a ratio of Ti-5Al-5Mo-5V-1Cr-1Fe to collect sponge titanium and intermediate alloys, and sort the sponge titanium and intermediate alloys on a sorting machine to remove unqualified raw materials; 2. Transfer the selected sponge titanium and intermediate alloy into the corresponding silos. Calculate and set the single-time feeding weight of each silo based on the weight of a single electrode and the composition ratio. After feeding, transport the materials to the re-weighing silo via belt for weighing. 3. The mixture is conveyed from the weighing hopper to the mixer for rotary mixing. The rotary mixing speed is 13 rpm and the mixing time is 1 min. 4. The mixture is fed into the feeding hopper and conveyed to the top of the pressing mold cavity; the top and bottom of the feeding hopper are respectively equipped with a feeding port and a discharging port. When feeding, the discharging port is closed, and the feeding hopper is driven to slowly rotate 160° around the horizontal axis at a speed of 3° / s, so that the feeding port rotates to the top of the mold cavity and feeds into the mold cavity from the feeding port, thus completing the rotation and reverse feeding. 5. Subsequently, the mixture in the mold cavity was pressed and shaped using a hydraulic press. When the pressure head reached 1.2 times the preset height of the electrode block, ultrasonic vibration was applied to the bottom of the pressing mold. The ultrasonic frequency was 20kHz, the power was 1500W, the action time was 15 seconds, and the pressing pressure was 35-45MN. Finally, an electrode block weighing 46kg and with a height of 190mm was obtained. The components at the bottom of the electrode block were evenly distributed, and the weight of the unformed raw material was 3.8g per electrode block.

[0016] Example 2 (Rotational reverse feeding + ultrasonic-assisted molding and pressing of φ480 / 2mm TC4 electrode block) 1. Use intermediate alloys such as Al (particle size 8-13mm) and Al-V (particle size 1-6mm) in the proportion of Ti-6Al-4V to collect sponge titanium and intermediate alloys, and use a sorting machine to remove unqualified raw materials from the sponge titanium and intermediate alloys. 2. Transfer the selected sponge titanium and intermediate alloy into the corresponding silos. Calculate and set the single-time feeding weight of each silo based on the weight of a single electrode and the composition ratio. After feeding, transport the materials to the re-weighing silo via belt for weighing. 3. The mixture is conveyed from the weighing hopper to the mixer for rotary mixing. The rotary mixing cycle is 13 revolutions / min and the mixing time is 1 minute. 4. Transfer the mixture into the feeding hopper and convey it to the top of the mold cavity; when discharging, close the discharge port and drive the feeding hopper to slowly rotate 160° around the horizontal axis at a speed of 3° / min, so that the feeding port is aligned with the mold cavity and the material is discharged from the feeding port, completing the rotation and reverse material discharge; 5. Subsequently, the mixture in the mold cavity is pressed and shaped using a hydraulic press. When the pressure head reaches 1.2 times the preset height of the electrode block, ultrasonic vibration is applied to the bottom of the pressing mold. The ultrasonic frequency is 20kHz, the power is 1500W, the action time is 10 seconds, and the pressing pressure is 30-40MN. Finally, an electrode block weighing 64kg and with a height of 200mm is obtained. The components at the bottom of the electrode block are evenly distributed, and the weight of the unformed raw material is 5.2g per electrode block.

[0017] Comparative Example 1 (TC18 electrode block with φ420 / 2mm specification pressed using conventional method) 1. Use intermediate alloys such as Al (particle size 8-13mm), Al-MO-V (particle size 0.1-3mm), Cr (particle size 0.5-3mm), Al-V (particle size 1-6mm), and Al-Fe (particle size 0.25-6mm) in a ratio of Ti-5Al-5Mo-5V-1Cr-1Fe to collect sponge titanium and intermediate alloys, and use a sorting machine to remove unqualified raw materials from the sponge titanium and intermediate alloys; 2. Transfer the selected sponge titanium and intermediate alloy into the corresponding silos. Calculate and set the single-time feeding weight of each silo based on the weight of a single electrode and the composition ratio. After feeding, transport the materials to the re-weighing silo via belt for weighing. 3. The mixture is conveyed from the weighing hopper to the mixer for rotary mixing. The rotary mixing cycle is 13 revolutions / min and the mixing time is 1 minute. 4. Transfer the mixture into the feeding hopper and convey it to the top of the mold cavity. Open the discharge port of the feeding hopper to complete the material feeding. After feeding, press the mixture at a pressure of 35-45MN to finally obtain an electrode block weighing 46kg and 190mm in height. The bottom end face of the electrode block is basically composed of fine-particle alloy, and the weight of the unformed raw material is 76.7g / electrode block.

[0018] Comparative Example 2 (TC4 electrode block with φ420 / 2mm specification pressed using conventional methods) 1. Use intermediate alloys such as Al (particle size 8-13mm) and Al-V (particle size 1-6mm) in the proportion of Ti-6Al-4V to collect sponge titanium and intermediate alloys, and use a sorting machine to remove unqualified raw materials from the sponge titanium and intermediate alloys. 2. Transfer the selected sponge titanium and intermediate alloy into the corresponding silos. Calculate and set the single-time feeding weight of each silo based on the weight of a single electrode and the composition ratio. After feeding, transport the materials to the re-weighing silo via belt for weighing. 3. The mixture is conveyed from the weighing hopper to the mixer for rotary mixing. The rotary mixing cycle is 13 revolutions / min and the mixing time is 1 minute. 4. The mixture is fed into the feeding hopper and conveyed to the top of the pressing mold cavity. The discharge port of the feeding hopper is opened to complete the feeding. After feeding, the mixture is pressed at a pressure of 30-40MN, finally producing an electrode block weighing 64kg and 200mm in height. The electrode block has a complete appearance, but the bottom end face is basically composed of fine-particle alloy. The weight of the unformed raw material is 45.2g / electrode block.

[0019] Comparative Example 3 (Conventional blanking + ultrasonic-assisted molding and pressing of φ420 / 2mm TC18 electrode blocks) 1. Use intermediate alloys such as Al (particle size 8-13mm), Al-MO-V (particle size 0.1-3mm), Cr (particle size 0.5-3mm), Al-V (particle size 1-6mm), and Al-Fe (particle size 0.25-6mm) in a ratio of Ti-5Al-5Mo-5V-1Cr-1Fe to collect sponge titanium and intermediate alloys, and use a sorting machine to remove unqualified raw materials from the sponge titanium and intermediate alloys; 2. Transfer the selected sponge titanium and intermediate alloy into the corresponding silos. Calculate and set the single-time feeding weight of each silo based on the weight of a single electrode and the composition ratio. After feeding, transport the materials to the re-weighing silo via belt for weighing. 3. The mixture is conveyed from the weighing hopper to the mixer for rotary mixing. The rotary mixing cycle is 13 revolutions / min and the mixing time is 1 minute. 4. Feed the mixture into the feeding hopper and convey it to the top of the pressing mold cavity. Open the discharge port to allow the mixture to fall into the mold cavity. 5. Subsequently, the mixture in the mold cavity is pressed and shaped using a hydraulic press. When the pressure head reaches 1.2 times the preset height of the electrode block, ultrasonic vibration is applied to the bottom of the mold. The ultrasonic frequency is 20kHz, the power is 1500W, the action time is 15 seconds, and the pressing pressure is 35-45MN. Finally, an electrode block weighing 46kg and with a height of 190mm is obtained. The bottom end face of the electrode block is basically composed of fine-particle alloy, and the weight of the unformed raw material is 12.4g / electrode block.

[0020] By comparing Examples 1 and 2 with Comparative Examples 1 and 2, it can be seen that: 1. The bottom end face of the electrode blocks prepared in Comparative Example 1 and Comparative Example 2 is basically composed of fine-particle alloy, showing obvious enrichment layer phenomenon, while the components at the bottom of the electrode blocks in Example 1 and Example 2 are evenly distributed, and the sponge titanium skeleton is clearly visible. 2. In Comparative Examples 1 and 2, the weight of the unformed raw material of the electrode blocks was as high as 76.7 grams and 45.2 grams, respectively. However, in Examples 1 and 2 using the scheme of the present invention, these figures dropped sharply to 3.8 grams and 5.2 grams, respectively, representing reductions of 95% (TC18) and 89% (TC4). This reduction in material loss from the "tens of grams" to the "grams" level fully demonstrates the powerful synergistic effect of "rotational reverse feeding" (optimizing macroscopic distribution) and "ultrasonic assistance at specific times" (enhancing microscopic bonding). 3. Compared with Example 1, Comparative Example 3 only reduced the rotating reverse feeding process; the remaining steps and raw materials were the same. However, a noticeable fine-particle alloy enrichment layer appeared at the bottom of Comparative Example 3. However, compared with Comparative Example 1, the weight of material loss in Comparative Example 3 was significantly reduced, and the localized detachment phenomenon observed in Comparative Example 1 was not observed at the bottom. This indicates that while ultrasonic-assisted pressing alone can reduce the weight of material loss at the bottom of the electrode block and increase density, it cannot fundamentally solve the problem of material stratification. This also fully demonstrates that the solution of this invention is not a simple superposition of the effects of two known methods, but rather, through unique parameter design and step connection, it produces a synergistic multiplier effect, solving the long-standing problem of stratification of various components in the electrode block, demonstrating significant technical effectiveness.

Claims

1. A method for pressing highly uniform titanium alloy electrode blocks, characterized in that, This is achieved through the following process: After mixing the raw materials, they are fed into the feeding hopper. The feeding hopper is then transported to the top of the pressing mold cavity, with the feeding hopper's inlet facing upwards, the outlet facing downwards, and the outlet valve closed. The feeding hopper is then rotated so that the feeding inlet faces downwards and is located above the pressing mold cavity, allowing material to be fed into the pressing mold cavity from the feeding inlet. After feeding, the mixture in the mold cavity is pressed. During the pressing stage, when the press head is pressed down to 1.2-1.5 times the preset height of the electrode block, ultrasonic vibration is applied to the bottom of the pressing mold cavity.

2. The method for pressing high-uniformity titanium alloy electrode blocks according to claim 1, characterized in that, The rotation speed of the aforementioned feeding hopper is controlled to be 2° / s-8° / s.

3. The method for pressing highly uniform titanium alloy electrode blocks according to claim 1 or 2, characterized in that, The parameters for the ultrasound and compression are as follows: ultrasound frequency 20kHz, power 1500W, action time 10-15 seconds, and compression pressure 35-65MN.

4. The method for pressing highly uniform titanium alloy electrode blocks according to claim 3, characterized in that, This can be achieved through the following steps: Step 1) Raw material preparation: Take out sponge titanium and intermediate alloy according to the predetermined mass ratio, and sort the sponge titanium and intermediate alloy on the sorting machine to remove unqualified raw materials; Step 2) Batching and reweighing: Transfer the selected sponge titanium and intermediate alloy into the corresponding bins. Calculate and set the single-discharge weight of each bin based on the weight of a single electrode and the composition ratio. After the discharging is completed, transport the materials to the reweighing bin for reweighing. Step 3) Mixing: Rotate and stir the weighed mixture at a speed of 12-14 rpm for 0.5-2 minutes. Step 4) Rotary feeding: After mixing, the material is transferred to the feeding hopper and transported to the top of the pressing mold cavity using a linear guide. When feeding, the feeding hopper is driven to rotate slowly around the horizontal axis by 140°-170° at a speed of 2° / s-8° / s, so that the feed inlet of the feeding hopper slowly rotates to the top of the mold cavity and feeds the material into the mold cavity from the feed inlet. Step 5) Ultrasonic Assisted Pressing: The mixture in the mold cavity is pressed. During the pressing stage, when the press head is pressed down to 1.2-1.5 times the preset height of the electrode block, ultrasonic vibration is applied to the bottom of the pressing mold. The ultrasonic and pressing parameters are controlled as follows: ultrasonic frequency 20kHz, power 1500W, action time 10-15 seconds, pressing pressure 35-65MN. The final pressed electrode block density is 3.2g / cm³-3.6g / cm³, and the pressing height is 180-200mm.

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