A surface nanocrystallized powder metalmolding device

Abstract

The application discloses a kind of surface nanocrystalline powder metalling device, including infiltration tank, transmission mechanism and clamping mechanism, it is characterized in that, the transmission mechanism is by fixed frame, input shaft, first bevel gear, second bevel gear and third bevel gear are formed, the infiltration tank is by left end cover, tank body and right end cover are formed, tank body inner surface is evenly provided with baffle, heating plate is arranged between tank body and heat preservation box, rotating shaft in tank body is provided with left sealing plate, right sealing plate and clamping mechanism, workpiece is installed on clamping mechanism, projectile and infiltrant are arranged between left sealing plate and right sealing plate, the linear velocity of projectile is 2.5~10m / s, the radius r of tank body and projectile linear velocity satisfy formula, beneficial to transmission mechanism so that tank body and rotating shaft produce reverse rotation, increase the relative impact velocity of projectile and workpiece, make plastic deformation on the surface of workpiece and form nanometer layer, effectively solve the problem that material after nanocrystallization pretreatment faces in heat expansion infiltration process.

Description

Technical Field

[0001] This invention relates to the field of surface strengthening of metallic materials, and in particular to a device for infiltrating metal with surface nanopowder. Background Technology

[0002] Defects and microcrystalline / nanostructures on the surface of metallic materials accelerate surface chemical reactions and diffusion processes, promoting the formation of surface coatings. Methods utilizing these factors to prepare coatings typically involve two steps: first, physical methods are used to alter the surface microstructure, forming microcrystalline / nanostructures with numerous defects; then, surface chemical thermal treatment is used to form a surface coating through the diffusion of active atoms. Zhang Wei et al., in their patent "A Low-Temperature Surface Carburizing Method for Titanium-Aluminum Based Intermetallic Compound Materials" (patent publication number: CN102409282A), employed a low-temperature carburizing technique for titanium-aluminum based intermetallic compound materials. Specifically, the surface of the metallic material was nanoscaled using conventional methods, followed by low-temperature carburizing at 500°C–800°C, resulting in a 4–9 μm thick carburized layer on the sample surface. However, nanostructured materials themselves face a problem—thermodynamic instability. Due to the extremely high interfacial volume percentage of nanomaterials, the large amount of excess free energy stored at the interface provides a very high driving force for grain growth. According to the Gibbs-Thomson equation, the driving force for grain growth is inversely proportional to the grain size. When the grain size is refined from the micrometer scale of traditional coarse-grained materials to the nanometer scale, the driving force for grain growth becomes very high. Many nanocrystalline materials even begin to grow grains at room temperature. Grain growth will cause nanomaterials to lose their unique microstructure and properties, such as diffusion properties. Studies have shown that chromium diffusion into hot-work die steel after nano-sizing pretreatment at different temperatures reveals that in the temperature range of 500-600 degrees Celsius, the thickness of the chromium-diffused layer increases with increasing temperature, reaching a maximum at 600 degrees Celsius. This is because higher temperatures favor element diffusion. However, from 600 to 700 degrees Celsius, the depth of the chromium-diffused layer decreases with increasing temperature. This is mainly because below 600 degrees Celsius, the non-equilibrium grain boundaries of the nanostructure dominate chromium diffusion, resulting in rapid diffusion. Above 600 degrees Celsius, as the grains coarsen, chromium diffusion gradually shifts from grain boundary diffusion to bulk diffusion, leading to a gradual decrease in diffusion performance. Above 700 degrees Celsius, grain coarsening is severe, and lattice diffusion becomes dominant. Therefore, nanomaterials consistently face the challenge of grain growth during thermal diffusion diffusion, and the thermal stability of the nanostructure surface is a key factor limiting the effectiveness of thermal diffusion diffusion.

[0003] To address the grain growth problem encountered during the thermal diffusion process of nanomaterials, inventor Chen Haifeng disclosed a mechanical energy-assisted nano-thermal diffusion device in his patent "A Mechanical Energy-Assisted Nanomaterial Thermal Diffusion Device" (Publication No.: CN202210029534.1). This device includes a diffusion tank, a planetary transmission mechanism, and a rotating shaft. The device is characterized by a left end cover, a tank body, and a right end cover. An internal gear ring and a baffle are provided on the inner surface of the tank. The left end cover is bolted to the input shaft, and the right end cover is connected to the support shaft via… The device uses bolted connections, with the input shaft connected to the motor. A heating plate is installed between the inner wall of the insulation box and the outer surface of the tank. The planetary transmission mechanism consists of planetary gears, planetary pins, a planetary carrier, and a sun gear. The planetary carrier is installed on the inner side of the left and right end covers, respectively. The planetary gears are mounted on the planetary carriers via planetary pins, and the sun gear is fixed on a rotating shaft with a boss. The workpiece is fixed on a workpiece clamping plate. The tank contains a penetrating agent and projectiles. When the penetrating tank rotates, a baffle causes the projectiles to fall from a height, impacting the workpiece surface and causing plastic deformation to form a nanolayer. However, in this patent, the planetary gears, planetary carrier, and sun gear of the planetary transmission mechanism are all movable. The sun gear can only rotate in the same direction as the planetary gears and the internal gear ring. The relative speed between the projectiles and the workpiece during collision is small, and the plastic deformation caused by the impact may not necessarily form a nanolayer. Summary of the Invention

[0004] The purpose of this invention is to propose a surface nanopowder infiltration device to solve the problem that when a projectile collides with a workpiece, the relative velocity is low and the plastic deformation caused by the impact may not necessarily form a nanolayer.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a surface nano-powder metal infiltration device, comprising an infiltration tank, a transmission mechanism, and a clamping mechanism, characterized in that the transmission mechanism consists of a fixed frame, an input shaft, a first bevel gear, a second bevel gear, and a third bevel gear; the first bevel gear is fixed on the input shaft; the second bevel gear is mounted on the fixed frame and can rotate around its axis; the third bevel gear passes through the fixed frame and is connected to a flange sleeve via a second coupling, and can rotate around the input shaft; the input shaft passes through the third bevel gear and is connected to a rotating shaft via a first coupling to the flange sleeve; the infiltration tank has a left end cover, The tank consists of a tank body and a right end cover. Baffles are evenly distributed on the inner surface of the tank body. The left end cover is fixedly connected to a flange sleeve. The right end cover is bolted to a support shaft, which is mounted on the right cover plate of the insulation box via bearings. A heating plate is installed between the tank body and the insulation box. A left sealing plate, a right sealing plate, and a clamping mechanism are installed on a rotating shaft inside the tank body. The workpiece is mounted on the clamping mechanism. The left and right sealing plates have clearance fits with the inner surface of the tank body. Shot and a penetrating agent are placed between the left and right sealing plates. The linear velocity of the shot is 2.5~10 m / s. The radius r of the tank body is related to the linear velocity of the shot. Satisfy the formula g is the acceleration due to gravity.

[0006] Preferably, the rotating shaft is a splined shaft.

[0007] Preferably, the clamping mechanism consists of an annular boss, a bushing, a clamping plate, and bolts, and the inner sides of the annular boss and the bushing are provided with keyways that mate with the rotating shaft.

[0008] Preferably, the module and the number of teeth of the first bevel gear, the second bevel gear and the third bevel gear are equal.

[0009] Preferably, the left end cap and the right end cap are fixed to both ends of the tank body by bolts.

[0010] Preferably, the left cover plate and the right cover plate are fixed to both ends of the insulation box by bolts.

[0011] Preferably, the left sealing plate and the right sealing plate are fixed to the rotating shaft by bolts.

[0012] Preferably, the gaps between the left and right sealing plates and the inner surface of the tank are smaller than the diameter of the seepage agent.

[0013] Preferably, the diameter of the projectile is 2-4 mm.

[0014] Preferably, the angle between the baffle and the inner wall of the tank is 30° to 60°.

[0015] Preferably, the infiltrator is composed of pure metal powder or alloy powder, filler and catalyst, and the composition ratio of the infiltrator by weight percentage is: 50-70% pure metal powder or alloy powder, 20-49% filler and 1-10% catalyst.

[0016] Preferably, the metal powder is zinc powder, or aluminum powder, or copper powder, or manganese powder; the alloy powder is chromium-aluminum, or iron-zinc, or iron-aluminum, or aluminum-rare earth alloy; the filler is alumina or silicon oxide; the catalyst is chloride or fluoride; and the powder particle size is 100-300 mesh.

[0017] The beneficial effects of this invention are that the transmission mechanism consists of a fixed frame, an input shaft, a first bevel gear, a second bevel gear, and a third bevel gear. The first bevel gear is fixed to the input shaft, the second bevel gear is mounted on the fixed frame and can rotate around its axis, and the third bevel gear passes through the fixed frame and is connected to the flange sleeve via a second coupling, and can also rotate around the input shaft. The input shaft passes through the third bevel gear and the flange sleeve and is connected to the rotating shaft via a first coupling. Therefore, the input shaft drives the rotating shaft to rotate while simultaneously driving the first bevel gear to rotate. The first bevel gear meshes with the second bevel gear, and the second bevel gear meshes with the third bevel gear. According to the meshing principle, the first and third bevel gears rotate in opposite directions. The third bevel gear is connected to the left end cover of the tank via the flange sleeve, causing the rotation direction of the tank to be opposite to the rotation direction of the rotating shaft. By utilizing uniformly arranged baffles inside the diffusion tank to drive the movement of the projectile and diffusion agent, when the tank rotates to a certain angle, the projectile and diffusion agent undergo a projectile motion under the combined action of gravity and centrifugal force, impacting the workpiece surface in multiple directions. Since the projectile's motion direction is opposite to the workpiece's rotation direction, the relative collision velocity between the projectile and the workpiece is increased, solving the problem of insufficient relative collision velocity in existing technologies. This facilitates plastic deformation on the workpiece surface, forming a nanolayer and creating vacancies necessary for the diffusion of numerous elements, thus accelerating the formation of the diffusion layer. The difference between this method and pre-nano-sizing followed by thermal diffusion diffusion is that, although grain recovery and the growth of new alloy phases occur during thermal diffusion diffusion, the impact of the projectile and diffusion agent also generates dislocations in the new alloy phase. This allows the grain nano-sizing process and the growth of the new phase to occur simultaneously, effectively solving the grain growth problem faced by materials pre-treated with nano-sizing during thermal diffusion diffusion.

[0018] However, if the impact velocity of the projectile is too low, it is difficult to generate sufficient plastic deformation on the workpiece surface, thus failing to create a nano-scale effect. If the impact velocity is too high, it can easily cause micro-cracks and other damage on the workpiece surface and subsurface, affecting the workpiece's service performance. Currently, commonly used methods for achieving surface nano-scaleing using projectile impact include rotary peening, surface mechanical grinding, ultrasonic peening, and high-energy peening. Among these, surface mechanical grinding uses projectiles with a diameter of 1~10mm, a vibration frequency of 50~20 kHz, and a projectile velocity of 5~20 m / s. In this application, since the number of teeth and module of the first, second, and third bevel gears in the transmission mechanism are equal, the rotational speed of the projectile and the workpiece are equal, and their directions of motion are opposite. Ignoring the influence of the workpiece mounting radius, the linear velocities of the projectile and the workpiece are equal in magnitude and opposite in direction. Therefore, setting the linear velocity of the projectile to 2.5~10 m / s ensures that a nano-layer is generated on the workpiece surface after the projectile impacts without causing microscopic damage to the workpiece surface. Furthermore, the projectile is acted upon by both gravity and centrifugal force during its motion. In a vertical position, when the centrifugal force on the projectile is greater than its gravity, the projectile will move in a circular motion along the inner wall of the container and will not fall. Only in a vertical position, when the centrifugal force on the projectile is less than its gravity, will the projectile undergo projectile motion under the combined action of gravity and centrifugal force. Therefore, the radius r of the container and the linear velocity of the projectile are related. Satisfy the formula .

[0019] The rotating shaft is a splined shaft. The clamping mechanism consists of an annular boss, a bushing, a clamping plate, and bolts. The annular boss and the inner side of the bushing are provided with keyways that mate with the rotating shaft, which facilitates the quick installation and positioning of the clamping mechanism on the rotating shaft. Attached Figure Description

[0020] Figure 1 This is a cross-sectional view of the present invention.

[0021] Figure 2 This is a schematic diagram of the seepage tank.

[0022] Figure 3 This is a schematic diagram of the transmission mechanism of the present invention.

[0023] Figure 4 This is a schematic diagram of the third bevel gear.

[0024] Figure 5 This is a schematic diagram of a ring-shaped boss.

[0025] Figure 6 This is a schematic diagram of the bushing.

[0026] Figure 7 This is a schematic diagram of the rotation axis.

[0027] Figure 8 This is a schematic diagram of a flange sleeve.

[0028] The markings in the diagram are: 1-Third bevel gear; 2-Second coupling; 3-Flange sleeve; 4-Left end cover; 5-Insulation box; 6-Tank body; 6a-Baffle; 7-Clamping plate; 8-Bolt; 9-Right sealing plate; 10-Right end cover; 11-Support shaft; 12-Bearing; 13-Right cover plate; 14-Shaft sleeve; 15-Bolt; 16-Annular boss; 17-Rotating shaft; 18-Heating plate; 19-Shot; 20-Left sealing plate; 21-First coupling; 22-Left cover plate; 23-Bearing; 24-First bevel gear; 25-Input shaft; 26-Fixed bracket; 27-Second bevel gear. Detailed Implementation Example 1

[0029] The present invention will be further described below with reference to specific embodiments. See also: Figures 1-8 A surface nano-powder metal infiltration device includes an infiltration tank, a transmission mechanism, and a clamping mechanism. The transmission mechanism comprises a fixed frame 26, an input shaft 25, a first bevel gear 24, a second bevel gear 27, and a third bevel gear 1. The first bevel gear 24 is fixed to the input shaft 25. The second bevel gear 27 is mounted on the fixed frame 26 and can rotate around its axis. The third bevel gear 1 passes through the fixed frame 26 and is connected to a flange sleeve 3 via a second coupling 2, and can rotate around the input shaft 25. The input shaft 25 passes through the third bevel gear 1 and the flange sleeve 3 and is connected to a rotating shaft 17 via a first coupling 21. The infiltration tank comprises a left end cover 4, a tank body 6, and a right end cover 10. The inner surface of the tank body 6 is uniformly provided with baffles 6a. The left end cover 4 is fixedly connected to the flange sleeve 3. The right end cover 10 is bolted to the support shaft 11. The support shaft 11 is mounted on the right cover plate 13 of the insulation box via bearings. A heating plate 18 is provided between the tank body 6 and the insulation box 5. A left sealing plate 20, a right sealing plate 9, and a clamping mechanism are provided on the rotating shaft 17 inside the tank body 6. The workpiece is mounted on the clamping mechanism. The left sealing plate 20 and the right sealing plate 9 are clearance fit with the inner surface of the tank body 6. A shot 19 and a penetrating agent are provided between the left sealing plate 20 and the right sealing plate 9. The linear velocity of the shot 19 is 2.5 m / s. The radius r of the tank body 6 and the linear velocity V of the shot 19 satisfy the formula... The radius of tank 6 is taken as 0.65m.

[0030] Rotating shaft 17 is a spline shaft.

[0031] The clamping mechanism consists of an annular boss 16, a bushing 14, a clamping plate 7, and bolts 8. The inner sides of the annular boss 16 and the bushing 14 are provided with keyways that mate with the rotating shaft 17.

[0032] The first bevel gear 24, the second bevel gear 27, and the third bevel gear 1 have the same module and number of teeth, respectively.

[0033] The left end cover 4 and the right end cover 10 are fixed to both ends of the tank body 6 by bolts.

[0034] The left cover plate 22 and the right cover plate 13 are fixed to both ends of the insulation box 5 by bolts.

[0035] The left sealing plate 20 and the right sealing plate 9 are fixed to the rotating shaft 17 by bolts.

[0036] The gap between the left sealing plate 20 and the right sealing plate 9 and the inner surface of the tank body 6 is smaller than the diameter of the seepage agent.

[0037] The diameter of the bullet is 2mm.

[0038] The angle between the baffle 6a and the inner wall of the tank 6 is 30°.

[0039] The infiltration agent is composed of pure metal powder, filler and catalyst. The composition ratio of the infiltration agent by weight percentage is: pure metal powder 40%, filler 57% and catalyst 3%.

[0040] The metal powder is aluminum or chromium powder, the filler is alumina, the catalyst is chloride, and the powder particle size is 100 mesh.

[0041] The working principle is as follows: The motor drives the rotating shaft and the first bevel gear to rotate through the input shaft. The first bevel gear meshes with the second bevel gear, and the second bevel gear meshes with the third bevel gear. The third bevel gear drives the tank to rotate in the opposite direction. The baffles evenly arranged inside the tank drive the shot and the penetrant to move. When the tank rotates to a certain angle, the shot makes a throwing motion under the combined action of gravity and centrifugal force, impacting the surface of the workpiece and causing it to undergo thermoplastic deformation to form a nano-layer. The penetrant is filled with penetrant, so the formation of surface defects and element diffusion of the material can be carried out simultaneously. Example 2

[0042] The present invention will be further described below with reference to specific embodiments. See also: Figures 1-8A surface nano-powder metal infiltration device includes an infiltration tank, a transmission mechanism, and a clamping mechanism. The transmission mechanism comprises a fixed frame 26, an input shaft 25, a first bevel gear 24, a second bevel gear 27, and a third bevel gear 1. The first bevel gear 24 is fixed to the input shaft 25. The second bevel gear 27 is mounted on the fixed frame 26 and can rotate around its axis. The third bevel gear 1 passes through the fixed frame 26 and is connected to a flange sleeve 3 via a second coupling 2, and can rotate around the input shaft 25. The input shaft 25 passes through the third bevel gear 1 and the flange sleeve 3 and is connected to a rotating shaft 17 via a first coupling 21. The infiltration tank consists of a left end cover 4, a tank body 6, and a right end cover 10 sets. The tank body 6 has baffles 6a evenly distributed on its inner surface. The left end cover 4 is fixedly connected to the flange sleeve 3. The right end cover 10 is bolted to the support shaft 11. The support shaft 11 is mounted on the right cover plate 13 of the insulation box via bearings. A heating plate 18 is provided between the tank body 6 and the insulation box 5. A left sealing plate 20, a right sealing plate 9, and a clamping mechanism are provided on the rotating shaft 17 inside the tank body 6. The workpiece is mounted on the clamping mechanism. The left sealing plate 20 and the right sealing plate 9 are clearance-fitted to the inner surface of the tank body 6. A shot 19 and a penetrating agent are provided between the left sealing plate 20 and the right sealing plate 9. The linear velocity of the shot 19 is 10 m / s. The radius r of the tank body 6 is related to the linear velocity of the shot 19. Satisfy the formula The radius of tank 6 is taken as 10.5m.

[0043] Rotating shaft 17 is a spline shaft.

[0044] The clamping mechanism consists of an annular boss 16, a bushing 14, a clamping plate 7, and bolts 8. The inner sides of the annular boss 16 and the bushing 14 are provided with keyways that mate with the rotating shaft 17.

[0045] The first bevel gear 24, the second bevel gear 27, and the third bevel gear 1 have the same module and number of teeth, respectively.

[0046] The left end cover 4 and the right end cover 10 are fixed to both ends of the tank body 6 by bolts.

[0047] The left cover plate 22 and the right cover plate 13 are fixed to both ends of the insulation box 5 by bolts.

[0048] The left sealing plate 20 and the right sealing plate 9 are fixed to the rotating shaft 17 by bolts.

[0049] The gap between the left sealing plate 20 and the right sealing plate 9 and the inner surface of the tank body 6 is smaller than the diameter of the seepage agent.

[0050] The diameter of the bullet is 4mm.

[0051] The angle between the baffle 6a and the inner wall of the tank 6 is 60°.

[0052] The infiltrator is composed of alloy powder, filler and catalyst. The composition ratio of the infiltrator by weight percentage is: alloy powder 75%, filler 20% and catalyst 5%.

[0053] The alloy powder is chromium-aluminum, the filler is alumina, the catalyst is chloride plus rare earth, and the powder particle size is 300 mesh.

[0054] The working principle is as follows: The motor drives the rotating shaft and the first bevel gear to rotate through the input shaft. The first bevel gear meshes with the second bevel gear, and the second bevel gear meshes with the third bevel gear. The third bevel gear drives the tank to rotate in the opposite direction. The baffles evenly arranged inside the tank drive the shot and the penetrant to move. When the tank rotates to a certain angle, the shot makes a throwing motion under the combined action of gravity and centrifugal force, impacting the surface of the workpiece and causing it to undergo thermoplastic deformation to form a nano-layer. The penetrant is filled with penetrant, so the formation of surface defects and element diffusion of the material can be carried out simultaneously.

Claims

1. A surface nanocrystalline powder pack cementitizing apparatus comprising a cementitizing pot, a transmission mechanism and a clamping mechanism, characterized in that, The transmission mechanism is composed of a fixed frame (26), an input shaft (25), a first bevel gear (24), a second bevel gear (27) and a third bevel gear (1), the first bevel gear (24) is fixed on the input shaft (25), the second bevel gear (27) is installed on the fixed frame (26) and can rotate around the axis, the third bevel gear (1) is connected with the flange sleeve (3) through the second coupling (2) and can rotate around the input shaft (25), the input shaft (25) is connected with the rotating shaft (17) through the first coupling (21) and the flange sleeve (3) passes through the third bevel gear (1); The tank is composed of a left end cover (4), a tank body (6) and a right end cover (10), the inner surface of the tank body (6) is uniformly provided with baffles (6a), the left end cover (4) is fixedly connected with the flange sleeve (3), the right end cover (10) is connected with the support shaft (11) through bolts, the support shaft (11) is installed on the right cover plate (13) of the heat preservation box through bearings, the left cover plate (22) and the right cover plate (13) are fixed on both ends of the heat preservation box (5) through bolts, the heating plate (18) is arranged between the tank body (6) and the heat preservation box (5), the rotating shaft (17) inside the tank body (6) is provided with a left sealing plate (20), a right sealing plate (9) and a clamping mechanism, the workpiece is installed on the clamping mechanism, the left sealing plate (20) and the right sealing plate (9) are both clearance fit with the inner surface of the tank body (6), the projectile (19) and the penetrating agent are arranged between the left sealing plate (20) and the right sealing plate (9), the linear velocity of the projectile (19) is 2.5-10 m / s, the radius r of the tank body (6) and the linear velocity V of the projectile (19) satisfy the formula r >= V 2 / g.

2. The apparatus for surface nanocrystallization powder metaliing according to claim 1, wherein, The rotating shaft (17) is a spline shaft.

3. The apparatus for surface nanocrystallization powder metaliing according to claim 1, wherein, The clamping mechanism is composed of an annular boss (16), a shaft sleeve (14), a clamping plate (7) and a bolt (8), and the inner side of the annular boss (16) and the shaft sleeve (14) are provided with key grooves matched with the rotating shaft (17).

4. The apparatus for surface nanocrystallization powder metaliing according to claim 1, wherein, The first bevel gear (24), the second bevel gear (27) and the third bevel gear (1) have equal modulus and tooth number.

5. The apparatus for surface nanocrystallization powder metaliing according to claim 1, wherein The left end cover (4) and the right end cover (10) are fixed on both ends of the tank body (6) by bolts.

6. The apparatus for surface nanocrystallization powder metaliing according to claim 1, wherein The left sealing plate (20) and the right sealing plate (9) are fixed on the rotating shaft (17) by bolts.

7. The apparatus for surface-nanocrystallized powder metallization according to claim 1, wherein The gap between the left sealing plate (20) and the right sealing plate (9) and the inner surface of the tank body (6) is less than the diameter of the infiltrant.

8. The apparatus for surface nanocrystallization powder metaliing according to claim 1, wherein, The diameter of the projectile is 2-4 mm.

9. The apparatus for surface nanocrystallization powder metaliing according to claim 1, wherein, The included angle between the baffle (6a) and the inner wall of the tank body (6) is 30°-60°.

10. The apparatus for surface nanocrystallization powder metaliing according to claim 1, wherein The infiltrant is composed of pure metal powder or alloy powder, a filler and a catalyst, and the component ratio of the infiltrant is as follows in terms of weight percentage: pure metal powder or alloy powder 50-70%, filler 20-49% and catalyst 1-10%.

11. A device for surface-nanocrystallized powder metallization according to claim 10, characterized in that The metal powder is zinc powder, or aluminum powder, or copper powder, or manganese powder, the alloy powder is chromium-aluminum, or iron-zinc, or iron-aluminum, or aluminum-rare earth alloy, the filler is aluminum oxide or silicon oxide, the catalyst is chloride or fluoride, and the particle size of the powder is 100-300 mesh.

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