Powder metallurgy die structure capable of preventing core rod from being broken

Abstract

The utility model relates to a powder metallurgy die structure capable of avoiding core rod breakage, which comprises an upper forming punch, a middle forming die and a lower forming punch, a forming channel penetrates through the middle forming die up and down, the lower forming punch is arranged in the forming channel, and a lower forming punching surface is arranged at the upper end of the lower forming punch. A boss protruding upwards is arranged on the lower forming punching face, an upper forming punching face is arranged at the lower end of the upper forming punch, and a penetrating hole matched with the boss is formed in the upper forming punching face in an up-down penetrating mode. The through hole is formed in the forming upper punching surface of the forming upper punch, so that material powder at a high-density part moves to the periphery in the extrusion forming process of powder, the density of the part is reduced, the pressure of a boss part on the forming lower punching surface is reduced, the boss is prevented from being broken, and the service life of the die is prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of powder metallurgy molds, and particularly relates to a powder metallurgy mold structure capable of avoiding the fracture of a core rod. Background Art

[0002] Powder metallurgy is a process technology that uses metals or metal powders as raw materials to manufacture metal materials, composites, and various types of products through forming and sintering. The forming mold is a key equipment in the production process of powder metallurgy products. When forming some types of hemispherical products, such as a ball bowl product 10 shown as follows, in the design of traditional powder metallurgy molds, generally, the upper punch and the lower punch are directly used for forming in cooperation. However, due to the very high density of the small end face part (part A) of the product, which can reach 7.5 g / cm Figure 3 , at such a high density, the part of the core rod boss of the lower punch die is prone to fracture after long-term operation, resulting in a low service life. 3 Summary of the Utility Model

[0003] The utility model aims to solve at least one of the problems existing in the related prior art to some extent. For this purpose, the utility model provides a powder metallurgy mold structure capable of avoiding the fracture of a core rod.

[0004] To achieve the above object, the utility model provides the following technical solutions:

[0005] A powder metallurgy mold structure capable of avoiding the fracture of a core rod includes a forming upper punch, a forming middle die, and a forming lower punch. A forming channel runs through the forming middle die up and down. The forming lower punch is arranged in the forming channel, and a forming lower punch surface is arranged at the upper end. A boss protruding upward is arranged on the forming lower punch surface. A forming upper punch surface is arranged at the lower end of the forming upper punch. A perforation cooperating with the boss is arranged through the forming upper punch surface up and down.

[0006] In some embodiments, the forming upper punch includes an outer upper punch and an inner upper punch. The perforation is arranged on the inner upper punch. A first through hole runs through the outer upper punch up and down. The inner upper punch is arranged in the first through hole.

[0007] In some embodiments, a first air hole communicating with the first through hole is arranged on one side of the outer upper punch.

[0008] In some embodiments, a second air hole communicating with the perforation is arranged on one side of the inner upper punch.

[0009] In some embodiments, an escape powder groove is arranged at the upper end of the forming channel. The diameter of the escape powder groove is larger than that of the forming channel.

[0010] In some embodiments, the forming lower punch includes a lower outer punch and a forming mandrel. The boss is provided at the upper end of the forming mandrel. The lower outer punch is vertically penetrated with a second through hole, and the forming mandrel is disposed in the second through hole.

[0011] Compared with the prior art, the beneficial effects of the present utility model are as follows: by providing a perforation on the forming upper punch surface of the forming upper punch, during the extrusion forming process of the powder, the material powder at the high-density part moves to the surrounding, so as to reduce the density of this part, reduce the pressure at the boss part on the forming lower punch surface, thereby avoiding the fracture of the boss and extending the service life of the mold. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is an exploded structural schematic diagram of the present utility model;

[0013] Figure 2 is a schematic diagram when the product of the present utility model is formed;

[0014] Figure 3 is a structural schematic diagram of a powder metallurgy product. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0015] The following specific implementation content provides various different embodiments or examples for implementing the present utility model. Of course, these are only embodiments or examples and are not intended to be restrictive. Additionally, repeated reference numerals may be used in different embodiments, such as repeated numbers and / or letters. These repetitions are for the purpose of simply and clearly describing the present utility model and do not represent a specific relationship between the different embodiments and / or structures discussed.

[0016] As Figures 1 - 3 shown, a powder metallurgy mold structure capable of avoiding the fracture of the mandrel includes a forming upper punch 1, a forming middle die 2, and a forming lower punch 3. The forming middle die 2 is vertically penetrated with a forming channel 4. The forming lower punch 3 is disposed in the forming channel 4, and a forming lower punch surface 5 is provided at the upper end. An upwardly protruding boss 6 is provided on the forming lower punch surface 5. A forming upper punch surface 7 is provided at the lower end of the forming upper punch 1. A perforation 8 cooperating with the boss 6 is vertically penetrated through the forming upper punch surface 7.

[0017] In the present utility model, by providing a perforation 8 on the forming upper punch surface 7 of the forming upper punch 1, when the forming upper punch surface 7 cooperates with the forming lower punch surface 5, during the extrusion forming process of the powder, the material powder at the high-density part moves towards the perforation 8, so as to reduce the density of this part, reduce the pressure at the boss 6 part on the forming lower punch surface 5, thereby avoiding the fracture of the boss 6 and extending the service life of the mold.

[0018] See Figure 1 、 Figure 2As shown, the forming upper punch 1 includes an outer upper punch 21 and an inner upper punch 22. The perforation 8 is provided on the inner upper punch 22. The outer upper punch 21 is vertically penetrated by a first through hole 23, and the inner upper punch 22 is arranged in the first through hole 23.

[0019] Further, a first air hole 31 communicating with the first through hole 23 is arranged on one side of the outer upper punch 21.

[0020] A second air hole 41 communicating with the perforation 8 is arranged on one side of the inner upper punch 22.

[0021] Thus, through the arrangements of the first air hole 31 and the second air hole 41, the air in the mold forming cavity can be discharged in time, which helps to improve the quality of product forming.

[0022] See Figure 1 、 Figure 2 As shown, a powder escape groove 51 is arranged at the upper end of the forming channel 4. The diameter of the powder escape groove 51 is larger than that of the forming channel 4, which can exclude excess powder and prevent the forming channel 4 from being blocked, thus affecting the compacting quality.

[0023] In the present utility model, the forming lower punch 3 includes an outer lower punch 61 and a forming mandrel 62. The boss 6 is arranged at the upper end of the forming mandrel 62. The outer lower punch 61 is vertically penetrated by a second through hole 63, and the forming mandrel 62 is arranged in the second through hole 63.

[0024] In the present utility model, the materials of the forming upper punch 1, the forming middle die 2 and the forming lower punch 3 are all SKH9 steel. They are relatively balanced in terms of wear resistance and toughness. Especially because it is only the increase or decrease of the carbon content, the high-temperature characteristics are not damaged. The steel properties can be continuously and significantly changed, and it is rich in hot-working and cold-working plasticity. The machinability and grindability are also good.

[0025] Combined with the above drawings and the display and description, the basic principles, main features and advantages of the present utility model have been shown. Those skilled in the art should understand that the present utility model is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present utility model. Without departing from the spirit and scope of the present utility model, the present utility model will have various changes and improvements, and these changes and improvements all fall within the scope of the present utility model claimed. The scope of protection claimed by the present utility model is defined by the appended claims and their equivalents.

Claims

1. A powder metallurgy die structure capable of avoiding mandrel fracture, comprising a forming upper punch (1), a forming middle die (2) and a forming lower punch (3), characterized in that: The forming middle die (2) is vertically penetrated with a forming channel (4). The forming lower punch (3) is arranged in the forming channel (4), and a forming lower punch surface (5) is arranged at the upper end. A convex platform (6) protruding upward is arranged on the forming lower punch surface (5). A forming upper punch surface (7) is arranged at the lower end of the forming upper punch (1). A perforation (8) which is arranged in cooperation with the convex platform (6) is vertically penetrated through the forming upper punch surface (7).

2. The powder metallurgy die structure capable of avoiding mandrel breakage according to claim 1, wherein: The forming upper punch (1) comprises an upper outer punch (21) and an upper inner punch (22). The perforation (8) is arranged on the upper inner punch (22). The upper outer punch (21) is vertically penetrated with a first through hole (23), and the upper inner punch (22) is arranged in the first through hole (23).

3. The powder metallurgy die structure capable of avoiding mandrel breakage according to claim 2, characterized in that: A first air hole (31) communicated with the first through hole (23) is arranged on one side of the upper outer punch (21).

4. A powder metallurgy die structure capable of avoiding mandrel breakage according to claim 2, characterized in that: A second air hole (41) communicated with the perforation (8) is arranged on one side of the upper inner punch (22).

5. The powder metallurgy die structure capable of avoiding mandrel breakage according to claim 1, wherein: An escape powder groove (51) is arranged at the upper end of the forming channel (4), and the diameter of the escape powder groove (51) is larger than that of the forming channel (4).

6. The powder metallurgy die structure capable of avoiding mandrel breakage according to claim 1, characterized in that: The forming lower punch (3) comprises a lower outer punch (61) and a forming mandrel (62). The convex platform (6) is arranged at the upper end of the forming mandrel (62). The lower outer punch (61) is vertically penetrated with a second through hole (63), and the forming mandrel (62) is arranged in the second through hole (63).

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