Cutter compression molding method

Abstract

The invention discloses a cutter compression molding method, and belongs to the technical field of powder pressing processes. The method comprises the steps that target powder is conveyed to a material boot provided with a telescopic vibration needle, vibration parameters are set according to the average particle size of the powder, and the insertion depth of the vibration needle is set according to the model of a tool; positioning the material shoe to enable the vibration needle to be aligned with a tool nose area of the mold cavity, driving the vibration needle to extend into the tool nose area in the mold cavity and vibrating according to set parameters; after vibration is completed, the vibration needle is withdrawn, and the material boot is driven to move away after reciprocating motion above the cavity; and then the powder in the cavity is pressed, so that a cutter pressed blank is obtained. In this way, through targeted vibration of the telescopic vibration needle, the powder filling density of the tool nose area can be improved, and the tool compact forming quality is improved. And moreover, the vibration parameters are set according to the average particle size of the powder, and the insertion depth of the vibration needle is set according to the model of the cutter, so that parameterization and self-adaptive adjustment of the process can be realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of powder pressing process, in particular to a cutter die forming method. BACKGROUND

[0002] Hard alloy cutter is widely used in the field of mechanical processing due to its high hardness, good wear resistance and other excellent characteristics. Die forming is a key process for preparing such cutter blanks, and its basic process is to fill the alloy powder with a certain proportion into the mold cavity, and then to make it form by closing the mold and pressing, so as to obtain a compact with a certain shape and density.

[0003] At present, the die press is usually composed of a die press body, a mold cavity forming a cutter shape, and a movable shoe for powder distribution (filling powder). The process flow of die forming is as follows: after the powder is delivered from the hopper to the shoe, the shoe moves above the cavity to complete the powder filling, and then moves away and performs pressing, so as to obtain a cutter compact.

[0004] However, due to the sharp shape and narrow space of the tip part of the mold cavity, the above-mentioned powder distribution method is easy to cause the powder in this area to be not filled and the density to be uneven. This defect is difficult to be compensated in the subsequent process, and often causes the tip to become the mechanical weak link of the entire compact, resulting in low cutting edge strength and use reliability of the cutter. SUMMARY

[0005] The embodiment of the present application provides a cutter die forming method. The technical scheme is as follows: The cutter die forming method comprises the following steps: acquiring target powder; filling the target powder into the hopper of the die press and delivering it to the shoe provided with a telescopic vibrating needle; setting the vibration parameters of the telescopic vibrating needle according to the average particle size of the target powder, and setting the insertion depth of the telescopic vibrating needle according to the cutter model; moving the shoe to above the mold cavity, so that the telescopic vibrating needle is located directly above the tip area in the mold cavity; driving the telescopic vibrating needle to extend into the tip area of the mold cavity by the insertion depth, and vibrating at the set vibration parameters; after the vibration reaches a preset time length, retracting the telescopic vibrating needle out of the mold cavity; driving the shoe to move away after reciprocating above the mold cavity, and pressing the powder in the mold cavity to obtain a cutter compact.

[0006] Optionally, an arc surface of the tip is formed on the side surface of the mold cavity. When the retractable vibrating needle is driven to extend into the die cavity to the depth of the insert tip region, the retractable vibrating needle is located on the angle bisector of the insert tip arc surface, and the distance between the retractable vibrating needle and the insert tip arc surface is 4 mm to 8 mm, and the distance between the end of the retractable vibrating needle and the bottom of the die cavity is 2 mm to 3 mm.

[0007] Optionally, the vibration parameters of the retractable vibrating needle include a vibration frequency and an amplitude, and the average particle size of the target powder is 50 μm to 100 μm. When the average particle size is less than or equal to 100 μm, the vibration frequency and the amplitude are negatively correlated with the average particle size. When the average particle size is greater than 100 μm, the vibration frequency and the amplitude are positively correlated with the average particle size.

[0008] Optionally, the vibration frequency of the retractable vibrating needle is 200 Hz to 1000 Hz, and the amplitude is 0.1 mm to 0.3 mm.

[0009] Optionally, the vibration preset time length is 0.2 seconds to 2 seconds.

[0010] Optionally, the material of the retractable vibrating needle includes tungsten steel.

[0011] Optionally, the diameter of the retractable vibrating needle is 0.5 mm to 1.5 mm.

[0012] Optionally, the target powder is in a granular form, the compressive strength of the powder particles of the target powder is greater than or equal to 2 MPa, the loose bulk density of the target powder is greater than or equal to 2.8 g / cm³, and the Hall flow rate of the target powder is less than or equal to 30 s / 50 g.

[0013] Optionally, the obtaining of the target powder includes: obtaining raw material powder and organic additive, the raw material powder including tungsten carbide powder and cobalt powder, and the organic additive including polyethylene glycol, sodium octadecanoate, and oleylamine ethoxylate; mixing the raw material powder and the organic additive to obtain a mixed material; spray granulating the mixed material to obtain the target powder.

[0014] Optionally, the addition amount of the organic additive is 1.4% to 2.8% of the total mass of the raw material powder. wherein the addition amount of the polyethylene glycol is 1.2% to 1.8%, the addition amount of the sodium octadecanoate is 0.1% to 0.5%, and the addition amount of the oleylamine ethoxylate is 0.1% to 0.5%.

[0015] The technical scheme provided by the embodiments of the present application has at least the following beneficial effects: The tool mold forming method is provided, the target powder is transported to the shoe with the retractable vibrating needle, the vibration parameters are set according to the average particle size of the powder, and the vibration needle insertion depth is set according to the tool model; then the shoe is positioned to make the vibrating needle aim at the tool tip area of the mold cavity, the vibrating needle is driven to extend into the tool tip area in the mold cavity and vibrate according to the set parameters; after the vibration is completed, the vibrating needle is withdrawn, and the shoe is driven to move away after reciprocating above the cavity; then the powder in the cavity is pressed to obtain a tool compact. In this way, the targeted vibration of the retractable vibrating needle can improve the powder filling density of the tool tip area and improve the tool compact forming quality.

[0016] Moreover, the method can realize parameterization and adaptive adjustment of the process by setting the vibration parameters according to the average particle size of the powder and setting the vibration needle insertion depth according to the tool model. The adaptability of the tool mold forming method to different specifications of powder can be improved, and the stability and repeatability of the process can be enhanced, thereby ensuring the overall density and consistency of the tool compact, especially the tool tip part. The technical problem of insufficient powder filling, low density and easy defects in the tool tip area in the related art hard alloy tool mold forming can be solved. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0018] Figure 1 is a structural schematic diagram of a mold pressing machine; Figure 2 is a flowchart of a tool mold forming method provided by the embodiments of the present application; Figure 3 is a flowchart of another tool mold forming method provided by the embodiments of the present application; Figure 4 is a structural schematic diagram of a shoe provided by the embodiments of the present application; Figure 5 is a perspective structural schematic diagram of a shoe provided by the embodiments of the present application; Figure 6 is a structural schematic diagram of a tool provided by the embodiments of the present application; Figure 7 is Figure 4 is a structural schematic diagram of another view of the shoe shown in FIG. 8; Figure 8 is Figure 7A cross-sectional structure schematic diagram of the material shoe along the A1-A2 position is shown. Figure 9 A schematic diagram of the position relationship between the telescopic vibration needle and the mold cavity is provided by the embodiment of the present application. DETAILED DESCRIPTION

[0019] Embodiments of the present application are described in detail below. The embodiments described below are exemplary only, and are not to be construed as limiting the present application.

[0020] The ranges disclosed herein are defined by the lower and / or upper limit of the range, given that the range is defined by selecting a lower limit and / or an upper limit. The ranges defined in this manner can include the end values or not, and can be combined arbitrarily, i.e. any lower limit can be combined with any upper limit to form a range not explicitly mentioned, and any lower limit can be combined with other lower limits to form a range not explicitly mentioned, and likewise any upper limit can be combined with any other upper limit to form a range not explicitly mentioned. In addition, each individual point or single value disclosed can itself be combined as a lower limit or upper limit with any other point or single value or with other lower limits or upper limits to form a range not explicitly mentioned.

[0021] If not specifically stated, all embodiments of the present application and optional embodiments can be combined with each other to form new technical solutions, and such technical solutions should be considered to be included in the disclosure of the present application.

[0022] Reference is made to Figure 1 , Figure 1 A schematic structural diagram of a die press, which can include a press body 11, a material shoe 12 and a material bin 13. The press body 11 is equipped with a mold cavity 111 of a specific shape, which can directly determine the geometric shape of the product (such as a tool). The material bin 13 is used to store the powder material to be formed, and the lower part of the material bin 13 is provided with a discharge port. The material shoe 12 serves as a material distribution mechanism, which is usually installed above the press body 11 and can move back and forth along a set path. During the operation of the die press, the material shoe 12 first receives a certain amount of powder falling from the material bin 13; then through a translational motion, the carried powder is accurately delivered to directly above the mold cavity 111, completing uniform material distribution. After the material distribution is completed, the material shoe 12 quickly moves out of the die pressing area to free up space for the pressing process. Then the press drives the upper die or the upper and lower dies to close, and applies high pressure to the powder in the mold cavity 111 to make it dense and form a green body of a predetermined shape.

[0023] However, the aforementioned molding press uses a static material distribution method, relying on gravity-fed material feeding and planar scraping. During the tool production process, when facing the complex-shaped tool tip area with sharp internal angles or narrow deep cavities in the mold cavity 111, the powder is prone to localized incomplete filling and low density in the tool tip area. This defect is difficult to remedy in subsequent processes, often making the tool tip the weakest point in the entire pressed blank, resulting in low cutting edge strength and reliability of the tool.

[0024] This application provides a tool molding method that can solve some or all of the technical problems in the above-mentioned related technologies.

[0025] Figure 2 This is a flowchart of a tool molding method provided in an embodiment of this application. The tool molding method may include the following steps: Step 201: Obtain the target powder.

[0026] Step 202: Load the target powder into the hopper of the molding press and convey it to the material shoe equipped with retractable vibrating needles.

[0027] Step 203: Set the vibration parameters of the retractable vibrating needle according to the average particle size of the target powder, and set the insertion depth of the retractable vibrating needle according to the tool model.

[0028] Step 204: Move the material shoe above the mold cavity so that the retractable vibrating pin is directly above the blade tip area in the mold cavity, wherein the mold cavity includes a blade tip area for forming the cutting edge of the tool.

[0029] Step 205: Drive the retractable vibrating needle to extend into the tip area of ​​the mold cavity at the insertion depth, and vibrate with the set vibration parameters.

[0030] Step 206: After the vibration reaches the preset duration, retract the retractable vibrating needle back to the outside of the mold cavity.

[0031] Step 207: Drive the material shoe to move back and forth above the mold cavity and then move away, pressing the powder in the mold cavity to obtain the tool blank.

[0032] In this process, when the material is distributed into the mold cavity through the material shoe, a retractable vibrating needle can be inserted into the tip area of ​​the mold cavity at the same time to vibrate the target powder in the tip area, thereby improving the flowability of the target powder in the tip area and thus improving the uniformity and density of powder distribution in the tip area.

[0033] In summary, this application provides a tool compression molding method. The method involves feeding target powder into a shoe equipped with a retractable vibrating needle, setting vibration parameters based on the average particle size of the powder, and setting the insertion depth of the vibrating needle according to the tool model. The shoe is then positioned so that the vibrating needle aligns with the tool tip area of ​​the mold cavity, driving the needle to extend into the tool tip area and vibrate according to the set parameters. After vibration, the vibrating needle is retracted, and the shoe is driven to reciprocate above the cavity before moving away. The powder within the cavity is then pressed to obtain a tool blank. Thus, the targeted vibration of the retractable vibrating needle can increase the powder filling density in the tool tip area, improving the tool blank molding quality.

[0034] Furthermore, this method enables parameterization and adaptive adjustment of the process by setting vibration parameters based on the average particle size of the powder and the insertion depth of the vibration pin according to the tool model. This improves the adaptability of the tool molding method to powders of different specifications, enhances process stability and repeatability, and ensures the overall density and consistency of the tool blank, especially the tip area. It can solve the technical problems of incomplete powder filling, low density, and susceptibility to defects in the tip area of ​​cemented carbide tool molding in related technologies.

[0035] Figure 3 This is a flowchart of another tool molding method provided in an embodiment of this application. This method can be used in a molding press and may include the following steps: Step 301: Obtain tungsten carbide powder, cobalt powder and organic additives.

[0036] The organic additives include polyethylene glycol (PEG), sodium stearate, and oleyl amine ethoxylate. For example, polyethylene glycol can be PEG-4000.

[0037] Tungsten carbide (WC) powder can have an average particle size of 1 μm and a purity of 99.9% or higher, while cobalt (Co) powder can have an average particle size of 0.8 μm and a purity of 99.5% or higher. Tungsten carbide powder and cobalt powder can be used as main raw materials.

[0038] Step 302: Mix the raw material powder with organic additives to obtain a mixed material.

[0039] The raw material powders include WC powder and Co powder. The raw material powders and organic additives are added to the mixer at a speed of 50 r / min for 52 h to ensure that the organic additives can be evenly coated on the surface of the powder particles.

[0040] In one optional embodiment, the amount of organic additives added to the mixed material is 1.4% to 2.8% of the total mass of the raw material powder; wherein, the amount of polyethylene glycol added is 1.2% to 1.8%, the amount of sodium stearate added is 0.1% to 0.5%, and the amount of oleylamine ethoxylate added is 0.1% to 0.5%.

[0041] For example, the raw material powder includes 90wt% WC powder, 10wt% Co powder, and the organic additives account for 2% of the total mass of the raw material powder, wherein polyethylene glycol (PEG-4000) accounts for 1.7% of the total raw material, sodium stearate accounts for 0.2% of the total raw material, and oleylamine ethoxylate accounts for 0.1% of the total raw material.

[0042] Step 303: Spray granulation of the mixed material to obtain the target powder.

[0043] In this embodiment, the target powder is prepared by spray granulation, which can be referred to as RTP (Ready-to-Press Powder) particles. The process parameters for spray granulation may include: inlet air temperature 180℃, outlet air temperature 80℃, and atomization pressure 0.8MPa. The average particle size of the resulting powder can be 100μm. In the formulation, polyethylene glycol (1.2%–1.8%) serves as the main binder to ensure particle strength; sodium octadecanoate and oleylamine ethoxylate (0.1%–0.5% each) act as dispersants and lubricants, jointly improving powder flowability. The three components work synergistically to obtain high-strength target powder particles.

[0044] The resulting target powder is granular, with a compressive strength greater than or equal to 2 MPa, a bulk density greater than or equal to 2.8 g / cm³, and a Hall flow rate less than or equal to 30 s / 50 g. This gives the target powder both high strength and good flowability, allowing it to maintain a particle breakage rate of ≤5% and a flowability retention rate of ≥90% during subsequent filling processes with vibration frequencies ranging from 200 Hz to 1000 Hz. This ensures uniform mold filling and reliable molding.

[0045] Step 304: Load the target powder into the hopper of the molding press and convey it to the shoe equipped with retractable vibrating needles.

[0046] A 5kg sample of cemented carbide target powder can be loaded into the hopper. The target powder can then be fed into the hopper through the connecting pipe between the hopper and the shoe.

[0047] Please refer to Figure 4 and Figure 5 , Figure 4 This is a schematic diagram of the structure of a material shoe provided in an embodiment of this application.Figure 5 This is a perspective structural diagram of a material shoe provided in an embodiment of this application. It can be understood that... Figure 5 The perspective structural diagram is only intended to clearly show the internal structure of the shoe and does not imply that the shoe is made of a transparent material. The molding press may include a controller, and the shoe may include a shoe body 121, a drive mechanism 122, and a retractable vibrating needle 123. The drive mechanism 122 is mounted on the outside of the shoe body 121 and is electrically connected to the controller. The retractable vibrating needle 123 is movably mounted on the shoe body 121. Under the control of the controller, the drive mechanism 122 can drive the retractable vibrating needle 123 to extend and retract.

[0048] In one exemplary embodiment, the controller controls the timing of the drive mechanism's actions to ensure that the retractable vibrating needle accurately extends and vibrates during the filling phase and retracts upon completion. The drive mechanism 122 may include a telescopic actuator and a high-frequency vibration generator, both connected to the retractable vibrating needle 123 and electrically connected to the controller. Exemplarily, the high-frequency vibration generator may include a piezoelectric ceramic vibrator or an electromagnetic vibrator; the telescopic actuator may include a cylinder or an electric cylinder.

[0049] The telescopic actuator drives the telescopic vibrating needle 123 to extend and retract vertically, enabling precise insertion at the working position and retraction / avoidance at the non-working position. The high-frequency vibration generator drives the telescopic vibrating needle 123 to vibrate horizontally at a high frequency and small amplitude after it has been inserted into the preset position in the mold cavity. This allows the telescopic vibrating needle 123 to break up the agglomeration of the target powder particles through its high-frequency vibration after insertion into the preset position in the mold cavity. During material shoe filling, the small amplitude vibration generated by the telescopic vibrating needle 123 promotes rapid flow and uniform filling of powder in the cutting edge area of ​​the mold cavity, eliminating filling dead zones.

[0050] In one optional embodiment, the retractable vibrating needle 123 may be made of tungsten steel. Tungsten steel possesses extremely high hardness, wear resistance, and appropriate toughness. Under conditions of repeated high-speed insertion, vibration, and friction with hard powder, the retractable vibrating needle 123 made of tungsten steel can resist wear, maintain its original diameter and surface finish, thereby ensuring stable insertion depth, consistent vibration transmission efficiency, and long-term process consistency. Simultaneously, the good rigidity of the retractable vibrating needle 123 can prevent bending or resonance deformation during vibration, resulting in better positioning accuracy.

[0051] Optionally, the diameter of the retractable vibrating needle 123 is 0.5mm to 1.5mm. For example, the diameter of the retractable vibrating needle 123 is 0.5mm, 0.6mm, 1.0mm, or 1.5mm. If the diameter of the retractable vibrating needle 123 is too small (<0.5mm), the retractable vibrating needle 123 will lack rigidity and is prone to bending or breaking during vibration or under pressure. If the diameter of the retractable vibrating needle 123 is too large (>1.5mm), the penetration volume of the retractable vibrating needle 123 will be too large, potentially causing excessive disturbance to the powder or even leaving pinholes in the mold cavity, affecting the uniformity of the fabric. Within this diameter range, the retractable vibrating needle 123 can possess sufficient structural strength for reliable operation while reducing the physical interference of the retractable vibrating needle 123 on the target powder.

[0052] Step 305: Set the vibration parameters of the retractable vibrating needle according to the average particle size of the target powder, and set the insertion depth of the retractable vibrating needle according to the tool model.

[0053] Optionally, the vibration parameters of the retractable vibrating needle include vibration frequency and amplitude, with the average particle size of the target powder ranging from 50 μm to 100 μm. When the average particle size is less than or equal to 100 μm, the vibration frequency and amplitude are negatively correlated with the average particle size; when the average particle size is greater than 100 μm, the vibration frequency and amplitude are positively correlated with the average particle size. That is, when the average particle size is less than or equal to 100 μm, the smaller the average particle size, the greater the vibration frequency and amplitude; when the average particle size is greater than 100 μm, the larger the average particle size, the greater the vibration frequency and amplitude.

[0054] For finer powders with an average particle size of 100 μm or less, which have a large specific surface area, poor flowability, and strong cohesion, using a higher frequency and amplitude vibration mode can effectively overcome interparticle forces and promote flow and rearrangement. For coarser powders with a particle size greater than 100 μm, it is necessary to moderately increase the vibration intensity to overcome their greater inertia. Thus, by designing rules with negative and positive correlations, it is possible to ensure that a better vibration effect can be obtained by adjusting parameters when the target powder particle size is different. This enhances the process's adaptability to different raw materials, thereby achieving a match between the vibration mode and the powder characteristics.

[0055] Since different tool models correspond to different mold cavity shapes, sizes and depths, the insertion depth of the retractable vibrating pin can be adjusted for different tool models. For example, the insertion depth of the retractable vibrating pin can be 5mm to 15mm.

[0056] In one exemplary embodiment, the material shoe parameters may include: a forward speed of 100 mm / s, a backward speed of 300 mm / s, a material shoe vibration position of 100 mm, a swing speed of 100 mm / s, a swing stroke of -20 mm, a swing count of 1, and a material shoe forward position of 130 mm. The material shoe vibration position refers to the position where the retractable vibrating needle extends and vibrates. The parameters of the retractable vibrating needle include: an insertion depth of 10 mm, a vibration frequency of 500 Hz, an amplitude of 0.1 mm, and a vibration time of 0.5 s. The molding press may also include a pressure head, whose parameters include: a pressing speed of 20 mm / s and a stamping ratio of 70%. Optionally, the retractable vibrating needle has a vibration frequency of 200Hz to 1000Hz and an amplitude of 0.1mm to 0.3mm. Within this range, the vibration of the retractable vibrating needle can provide sufficient energy to break up powder agglomerates and promote dense filling. Because of its small amplitude, it can avoid causing violent disturbance or splashing to the powder that has been initially positioned, thereby ensuring the stability and precision of the fabric application process and achieving a high-frequency micro-amplitude vibration mode.

[0057] Step 306: Move the material shoe to the top of the mold cavity so that the retractable vibrating needle is directly above the blade tip area in the mold cavity.

[0058] The material shoe can be moved to the target position and stay there so that the retractable vibrating needle can be aligned with the tip area of ​​the die cavity.

[0059] Step 307: Drive the retractable vibrating needle to extend into the tip area of ​​the mold cavity at the insertion depth, and vibrate with the set vibration parameters.

[0060] For example, the material shoe automatically advances to 100mm according to the preset program, and the target powder in the material shoe fills the mold cavity. At the same time, the retractable vibrating needle is inserted into the mold cavity at an insertion depth of 10mm and vibrates at a frequency of 500Hz.

[0061] Please refer to Figure 6 , Figure 7 , Figure 8 and Figure 9 , Figure 6 This is a schematic diagram of the structure of a cutting tool 20 provided in an embodiment of this application. Figure 7 yes Figure 4 The diagram shows another structural view of the material boot. Figure 8 yes Figure 7 The diagram shows a cross-sectional structure of the material shoe along the A1-A2 position. Figure 9This is a schematic diagram illustrating the positional relationship between a retractable vibrating needle 123 and a mold cavity 111 provided in this embodiment. The cutting tool 20 can be a quadrangular prism-shaped cutting tool with two cutting edges. Cutting edges 21 are symmetrically arranged on two opposite side edges of the cutting tool 20, with rounded transitions. The position of the cutting edge 21 corresponds to the cutting edge region in the mold cavity. In this embodiment, the number of retractable vibrating needles 123 in the shoe can be the same as the number of cutting edges 21 of the cutting tool 20. When both the number of retractable vibrating needles 123 and the number of cutting edges 21 of the cutting tool 20 are multiple, the retractable vibrating needles 123 correspond one-to-one with the cutting edges of the cutting tool. The cutting tool in this embodiment can also be a cutting tool of other shapes, such as a triangular prism-shaped cutting tool or a pentagonal prism-shaped cutting tool; this embodiment does not limit the shape.

[0062] Optionally, two retractable vibrating pins 123 are symmetrically arranged on the shoe, and a blade tip arc surface is formed on the side of the mold cavity 111. When the retractable vibrating pins 123 are driven to extend into the blade tip area of ​​the mold cavity 111 to the insertion depth, the retractable vibrating pins 123 are located on the angle bisector of the blade tip arc surface, and the distance h1 between the retractable vibrating pins 123 and the blade tip arc surface is 4 mm to 8 mm, and the distance h2 between the end of the retractable vibrating pins 123 and the bottom of the mold cavity 111 is 2 mm to 3 mm. For example, the distance h1 between the retractable vibrating pins 123 and the blade tip arc surface is 4 mm, 5 mm, 6 mm or 8 mm, and the distance h2 between the end of the retractable vibrating pins 123 and the bottom of the mold cavity 111 is 2 mm, 2.6 mm, 2.8 mm or 3 mm.

[0063] By positioning the vibrating needle at the bisector of the angle 4mm to 8mm from the curved surface of the cutting edge, and controlling the distance between the needle tip and the bottom of the cavity to be 2mm to 3mm, it is possible to ensure that the vibration energy is precisely delivered to the junction of the stress concentration area and the weak point of the cutting edge. If the distance is too close to the curved surface, it may interfere with the contour; if it is too far, the effect will be insufficient. If the distance is too close to the bottom, it may scratch the mold; if it is too far, the effect on the deep powder will be weak. Within this range, the repeatability and geometric accuracy of the cutting edge forming quality can be improved.

[0064] Step 308: After the vibration reaches the preset duration, retract the retractable vibrating needle back to the outside of the mold cavity.

[0065] During the vibration of the retractable vibrating needle, the material shoe remains stationary, meaning that during the 0.5-second vibration duration, the material shoe remains at the target position.

[0066] Optionally, the vibration preset duration is 0.2 seconds to 2 seconds. For example, the vibration preset duration is 0.2 seconds, 0.5 seconds, 1.5 seconds, or 2 seconds. After the retractable vibrating needle completes its vibration, it can be withdrawn from the mold cavity and automatically returned to its original position. In other words, after the vibration process ends, the controller instructs the high-frequency vibration generator to stop working, and then the telescopic driver retracts the retractable vibrating needle 123 upwards, causing it to retract into the material shoe body and return to its initial state. The end of the retractable vibrating needle 123 in the retracted state is located inside the material shoe body 121 or flush with the bottom surface of the material shoe, preventing the retractable vibrating needle 123 from interfering with the movement of the material shoe or scratching the press body.

[0067] By controlling the vibration duration between 0.2 and 2 seconds, a balance can be achieved between compaction effect and production efficiency. If the vibration duration is too short (<0.2 seconds), it may result in insufficient energy input, inadequate powder weight repositioning, and weak compaction effect; if the vibration duration is too long (>2 seconds), it will reduce the production rate and may also cause powder segregation or local hardening due to excessive vibration.

[0068] Step 309: Drive the material shoe to reciprocate above the mold cavity and then move away.

[0069] After the retractable vibrating needle completes local compaction of the blade tip area and retracts, the drive shoe continues to move and performs at least one reciprocating oscillation. For example, the shoe advances 30mm, oscillates once, and then retracts to the starting position. This allows the remaining target powder in the shoe to be redistributed evenly above the mold cavity, eliminating localized powder accumulation or marks that may have been caused by the insertion and vibration of the retractable vibrating needle, thus ensuring uniform filling of the entire cavity. The oscillation motion further promotes the smoothing and densification of the target powder, equivalent to actively combing and leveling the overall material distribution after local compaction. This improves the overall density consistency of the compact, making the transition from localized strengthening to overall molding smoother and more reliable.

[0070] In an optional embodiment, the molding press may further include a cavity vibration mechanism, which may be disposed around the periphery of the mold cavity. Exemplarily, the cavity vibration mechanism may be mounted on the press body or integrated into the internal structure of the press. The cavity vibration mechanism may include at least one of a piezoelectric ceramic vibration mechanism, a pneumatic resonant mechanism, and an ultrasonic vibration mechanism. For example, a piezoelectric ceramic actuator may be mounted on the outside or bottom of the mold cavity, and a controller may drive the piezoelectric ceramic actuator to generate high-frequency, low-amplitude mechanical vibration, which is directly transmitted to the entire mold cavity.

[0071] The cavity vibration mechanism is used to excite the mold cavity itself to generate high-frequency, micro-amplitude vibrations while the material shoe reciprocates above the mold cavity to fill powder. This overall vibration provides three-dimensional energy to the target powder within the cavity, improving the overall flowability of the powder and thus enhancing the uniformity and density of powder distribution over a wider area.

[0072] In addition, the overall vibration of the cavity can dissipate local powder accumulation or weak traces that may be caused by the insertion and vibration of the retractable vibrating needle, further eliminating local filling defects and ensuring filling consistency from the microscopic local to the macroscopic overall.

[0073] In this embodiment, by combining the local fine turbulence of the retractable vibrating needle with the overall vibration of the cavity vibration mechanism, local and global vibration energy can be sequentially applied to the target powder in the mold cavity. This multi-layered, complementary vibration improves the flowability and filling uniformity of the target powder in the complex cavity, thereby reducing the risk of filling defects and improving the density distribution uniformity of the compact pressed by the tool.

[0074] Step 310: Press the powder in the mold cavity to obtain the tool blank.

[0075] After the shoe is removed, the pressure head presses down to complete the subsequent pressing and obtain the carbide tool blank.

[0076] Step 311: Sinter the tool blank.

[0077] Steps 301 to 310 can be repeated to obtain more tool blanks; for example, 200 tool blanks are obtained. Simultaneously, 200 blade blanks can be formed using a conventional die-pressing press, following a process without the retractable vibrating needle vibration step, as a control group. Both types of tool blanks are then placed in a vacuum sintering furnace for sintering at a temperature of 1450°C for 1 hour to obtain two types of cemented carbide tool samples.

[0078] Step 312: Perform a density test on the cutting tool.

[0079] Ten samples of each of the two types of cemented carbide cutting tools were taken, and the cemented carbide cutting tool samples were cut into 6 equal parts. The tip part and the middle part were taken, and the surface was polished to remove the cutting marks. The alloy density was tested by the water displacement method, and the test results are shown in Table 1.

[0080] Table 1

[0081] As shown in Table 1, the tip density of the cemented carbide cutting tool formed by the tool molding method in this application embodiment can be increased from 14.344 g / cm³. 3 Increased to 14.390 g / cm³ 3 The relative density increased by 3.2%, from 99.55% to 99.85%, an increase of 3%.

[0082] Although this application can readily be embodied in various forms, only some specific embodiments are shown in the accompanying drawings and will be described in detail in this specification. It is understood that this specification should be regarded as an exemplary illustration of the principles of this application and is not intended to limit the application to what is described herein.

[0083] Therefore, a feature pointed out in this specification is used to describe one feature of one embodiment of this application, and does not imply that every embodiment of this application must have the described feature. Furthermore, it should be noted that this specification describes many features. While certain features may be combined to illustrate possible system designs, these features may also be used in other combinations not explicitly stated. Therefore, unless otherwise stated, the described combinations are not intended to be limiting.

[0084] In the embodiments shown in the accompanying drawings, the directional indications (such as up, down, left, right, front, and back) used to explain the structure and movement of the various elements of this application are relative rather than absolute. These descriptions are appropriate when these elements are in the positions shown in the drawings. If the descriptions of the positions of these elements change, these directional indications also change accordingly.

[0085] In this application, the terms "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The term "multiple" means two or more, unless otherwise expressly defined.

[0086] The above description is merely an optional embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method of die forming a cutting tool, characterized by, The method comprises the following steps: acquiring a target powder; loading the target powder into a hopper of a die press and conveying the target powder to a shoe provided with a retractable vibrating needle; setting vibration parameters of the retractable vibrating needle according to an average particle size of the target powder and setting an insertion depth of the retractable vibrating needle according to a tool type; moving the shoe to above a mold cavity so that the retractable vibrating needle is located directly above a tool tip area in the mold cavity; driving the retractable vibrating needle to extend into the tool tip area of the mold cavity by the insertion depth and vibrate at the set vibration parameters; after the vibration reaches a preset time length, retracting the retractable vibrating needle out of the mold cavity; driving the shoe to move away after reciprocating above the mold cavity, and pressing the powder in the mold cavity to obtain a tool compact.

2. The method of claim 1, wherein, A side surface of the mold cavity is formed with a tool tip arc surface; when the retractable vibrating needle extends into the tool tip area of the mold cavity by the insertion depth, the retractable vibrating needle is located on an angle bisector of the tool tip arc surface, and the distance between the retractable vibrating needle and the tool tip arc surface is 4 mm-8 mm, and the distance between the end of the retractable vibrating needle and the bottom of the mold cavity is 2 mm-3 mm.

3. The method of claim 1, wherein, The vibration parameters of the retractable vibrating needle include a vibration frequency and an amplitude, and the average particle size of the target powder is 50 μm-100 μm; when the average particle size is less than or equal to 100 μm, the vibration frequency and the amplitude are negatively correlated with the average particle size; when the average particle size is greater than 100 μm, the vibration frequency and the amplitude are positively correlated with the average particle size.

4. The method of claim 1, wherein, The vibration frequency of the retractable vibrating needle is 200 Hz-1000 Hz, and the amplitude is 0.1 mm-0.3 mm.

5. The method of claim 1, wherein, The preset vibration time length is 0.2 s-2 s.

6. The method of claim 1, wherein, The material of the retractable vibrating needle includes tungsten steel.

7. The method of claim 6, wherein, The diameter of the retractable vibrating needle is 0.5 mm-1.5 mm.

8. The method of claim 1, wherein, The target powder is in a granular form, the compressive strength of the powder particles of the target powder is greater than or equal to 2 MPa, the loose bulk density of the target powder is greater than or equal to 2.8 g / cm³, and the Hall flow rate of the target powder is less than or equal to 30 s / 50 g.

9. The method of claim 1, wherein, The method of acquiring the target powder comprises the following steps: acquiring raw material powder and organic additive, the raw material powder comprising tungsten carbide powder and cobalt powder, and the organic additive comprising polyethylene glycol, sodium octadecanoate and oleylamine ethoxylate; mixing the raw material powder and the organic additive to obtain a mixed material; spray granulating the mixed material to obtain the target powder.

10. The method of claim 9, wherein, The addition amount of the organic additive is 1.4%-2.8% of the total mass of the raw material powder; wherein, the addition amount of the polyethylene glycol is 1.2%-1.8%, the addition amount of the sodium octadecanoate is 0.1%-0.5%, and the addition amount of the oleylamine ethoxylate is 0.1%-0.5%.

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