A pre-die of a metal wire drawing die

Abstract

The application discloses a pre-mold of a metal wire drawing die and relates to the technical field of metal material manufacturing. The pre-mold comprises a die sleeve, a die core, a sintered body and a die cover, the center of the die sleeve is provided with the die core, the die core is made of diamond, the periphery of the die core is filled with the sintered body, and the sintered body is externally provided with the die cover matched with the die sleeve; the sintered body is made of multiple filling materials, and the filling materials are composed of the following components in percentage by volume: WC 80-85%; Co 8-12%; Ni 2-5%; Cu 2-3%; Mn 1-2%; and Si 0.1-1%. The pre-mold has high tensile strength, is not prone to deformation, has long service life and high practicability by changing the formula of the traditional filling material, so that the hardness of the sintered body can reach 120-128.

Description

Technical Field

[0001] This invention relates to the field of metal material manufacturing technology, specifically to a pre-mold for metal wire drawing. Background Technology

[0002] A wire drawing die (also known as a pre-forming die) is a tool used to perform preliminary plastic deformation on the metal wire before the final wire drawing process. Its main purpose is to bring the shape and dimensions of the metal wire close to the final desired shape, so that the required precision and surface quality can be achieved more effectively in the subsequent wire drawing process. Pre-dies are typically made of cemented carbide or other wear-resistant materials to ensure their stability under high pressure and high friction conditions for extended periods.

[0003] Currently, the pre-forming process for most metal wire drawing dies on the market is as follows: A diamond for making the die hole is placed in the center of a metal mold sleeve. A mixture of powders from various materials, mixed in a specific ratio, is used as the filler. This mixture is then filled into the metal mold sleeve, sealed, and placed on a sintering machine. It is heated and pressurized for several minutes, then allowed to cool naturally. However, the filler currently used has unsuitable material composition and ratios. After sintering, the resulting pre-die has insufficient tensile strength, low HRB hardness, and poor impact resistance in the sintered filler mixture. This makes the sintered material prone to deformation and outward expansion during the high-intensity extrusion pressure generated during wire drawing. This can cause the die to crack and burst during hard wire drawing, failing to achieve the ideal state for hard wire drawing. Such dies have a short service life and cannot effectively control the straightness and coil diameter of the drawn wire, leading to an increased scrap rate.

[0004] Therefore, this invention designs a pre-mold for metal wire drawing dies that has higher hardness, better performance, and longer lifespan. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a pre-mold for metal wire drawing, which is reasonably designed, has high tensile strength, is not easily deformed, has a long service life, and is highly practical.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a pre-mold for drawing metal wire, comprising a mold sleeve, a mold core, a sintered body, and a mold cover. The mold core is located at the center of the mold sleeve and is made of diamond. The mold core is surrounded by a filled sintered body, and a mold cover that mates with the mold sleeve is located outside the sintered body. The sintered body is made of a variety of fillers, which are composed of the following components in volume percentage: WC 80-85%; Co 8-12%; Ni 2-5%; Cu 2-3%; Mn 1-2%; Si 0.1-1%.

[0007] Preferably, the filler is composed of the following components by volume percentage: WC 80%; Co 10%; Ni 5%; Cu 3%; Mn 1%; Si 1%.

[0008] Preferably, the filler is composed of the following components by volume percentage: WC 85%; Co 9%; Ni 2%; Cu 2%; Mn 1.5%; Si 0.5%.

[0009] A process for preparing a pre-mold for drawing metal wire includes the following steps:

[0010] 1. First, the filler of the above volume percentage is made into powder and mixed evenly using a mixer; then, a lubricant is added to the powder to improve its flowability.

[0011] 2. Place the diamond mold core in the center of the mold sleeve, then fill the powder mixed in step 1 around the mold core, and seal it with the mold cover to obtain the pre-mold of the metal wire drawing die to be formed.

[0012] 3. Place the pre-mold of the metal wire drawing die to be formed in step 2 into a high-temperature furnace for sintering. The time from room temperature to sintering temperature is 1-2 hours. The sintering temperature is 850-860℃ and held for 2-3 hours. During the sintering process, Co acts as a binder and penetrates into the WC powder to form a strong bond with an HRB of 120-128.

[0013] 4. After sintering, the pre-mold is allowed to cool naturally to 350-360℃ in the high-temperature furnace before being removed and cooled to room temperature.

[0014] Preferably, the sintering temperature is 850°C.

[0015] The beneficial effects of the present invention are as follows: By changing the traditional filler formulation, the hardness of the sintered material can reach 120-128, and the prepared preform has high tensile strength, is not easily deformed, has a long service life, and is highly practical. Attached Figure Description

[0016] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments;

[0017] Figure 1 This is a schematic diagram of the pre-molded structure of the present invention. Detailed Implementation

[0018] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0019] Reference Figure 1 The specific embodiment adopts the following technical solution: a pre-mold for drawing metal wire, including a mold sleeve 1, a mold core 2, a sintered body 3, and a mold cover 4. The mold core 2 is disposed at the center of the mold sleeve 1. The mold core 2 is made of diamond. The mold core 2 is surrounded by a filled sintered body 3. The sintered body 3 is provided with a mold cover 4 that cooperates with the mold sleeve 1 on the outside. The sintered body 3 is made of a variety of fillers. The fillers are composed of the following components in volume percentage: WC 80-85%; Co 8-12%; Ni 2-5%; Cu 2-3%; Mn 1-2%; Si 0.1-1%.

[0020] A process for preparing a pre-mold for drawing metal wire includes the following steps:

[0021] 1. First, the filler of the above volume percentage is made into powder and mixed evenly using a mixer; add lubricant to the powder to improve its flowability; this can ensure the uniform distribution of material components and improve the operation performance in subsequent processing.

[0022] 2. Place the diamond die core in the center of the die sleeve, then fill the area around the die core with the powder mixed in step 1, and seal it with the die cap to obtain the pre-mold of the metal wire drawing die to be formed; ensure that the powder is evenly distributed around the die core to ensure the quality of the final pre-mold. Assembling the pre-mold in this way can effectively control the shape and dimensional accuracy of the die.

[0023] 3. Place the pre-mold of the metal wire drawing die to be formed in step 2 into a high-temperature furnace for sintering. The time from room temperature to sintering temperature is 1-2 hours, the sintering temperature is 850-860℃, and it is maintained for 2-3 hours. During the sintering process, Co acts as a binder and penetrates into the WC powder to form a strong bond with an HRB of 120-128. This can significantly improve the strength and wear resistance of the die.

[0024] 4. After sintering, the pre-mold is naturally cooled to 350-360℃ in the high-temperature furnace. The pre-mold is then removed and cooled to room temperature. The slow cooling process helps to reduce the stress caused by temperature changes in the pre-mold, thereby reducing the risk of pre-mold deformation and ensuring the stability and service life of the mold.

[0025] It is worth noting that the sintering temperature is 850℃.

[0026] It is worth noting that the filler is composed of the following components by volume percentage: WC 80%; Co 10%; Ni 5%; Cu 3%; Mn 1%; Si 1%.

[0027] Furthermore, the filler is composed of the following components by volume percentage: WC 85%; Co 9%; Ni 2%; Cu 2%; Mn 1.5%; Si 0.5%.

[0028] The pre-mold of this specific embodiment has high hardness and wear resistance. Using diamond as the core material gives it extremely high hardness and wear resistance, enabling it to withstand high-intensity wire drawing operations and extending the mold's service life.

[0029] This specific embodiment exhibits excellent heat resistance. The sintered body uses WC (tungsten carbide) as the main component. WC has high heat resistance and high-temperature stability, and can maintain good performance in high-temperature environments. It also has good toughness. The addition of alloying elements such as Co (cobalt), Ni (nickel), and Cu (copper) can improve the toughness and impact resistance of the sintered body, reducing the risk of mold breakage during use. In addition, it enhances corrosion resistance. The addition of Mn (manganese) and Si (silicon) can improve the corrosion resistance of the material, enabling the mold to maintain a stable working state even in harsh environments.

[0030] The pre-die of the metal wire drawing die in this specific embodiment has a uniform performance distribution: through a reasonable formula and sintering process, various components in the sintered body can be evenly distributed, thereby ensuring the overall performance and consistency of the die.

[0031] This specific embodiment allows for optimization of mold performance by adjusting the component ratios in the formula to meet the drawing requirements of different metal wires, depending on various application needs. Compared to molds made entirely of expensive materials, this design, by filling the mold core with a sintered body, ensures high performance in key areas while reducing overall costs, offering a high cost-performance ratio. Furthermore, the mold cover design facilitates easy maintenance and replacement during use, reducing downtime and maintenance costs.

[0032] The preparation process of the metal wire drawing die pre-mold in this specific embodiment ensures product quality through rigorous steps. From powder preparation and mixing to pre-mold assembly, high-temperature sintering, and final cooling, each step aims to improve the die's performance and durability. In particular, the cobalt infiltration and slow cooling process during high-temperature sintering significantly enhance the die's strength and stability, enabling the final product to meet high-performance requirements.

[0033] This specific embodiment changes the traditional filler formulation, enabling the hardness after sintering to reach 120-128. The resulting preform has high tensile strength, is not easily deformed, has a long service life, and is highly practical.

[0034] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A process for preparing a pre-mold for drawing metal wire, characterized in that, The pre-mold includes a mold sleeve (1), a mold core (2), a sintered body (3), and a mold cover (4). The mold core (2) is located at the center of the mold sleeve (1). The mold core (2) is made of diamond. The sintered body (3) is filled around the mold core (2). The mold cover (4) that matches the mold sleeve (1) is located on the outside of the sintered body (3). The sintered body (3) is made of filler material, which is composed of the following components in volume percentage: WC 80-85%; Co 8-12%; Ni 2-5%; Cu 2-3%; Mn 1-2%; Si 0.1-1%. The preparation process includes the following steps: (1) First, the filler is made into powder and mixed evenly by a mixer; a lubricant is added to the powder to improve its flowability; (2) Place the diamond mold core in the center of the mold sleeve, then fill the powder mixed in step (1) around the mold core, and seal it with the mold cover to obtain the pre-mold of the metal wire drawing mold to be formed. (3) Place the pre-mold of the metal wire drawing die to be formed in step (2) into a high-temperature furnace for sintering. The time from room temperature to sintering temperature is 1-2 hours, the sintering temperature is 850-860℃, and it is maintained for 2-3 hours. During the sintering process, Co acts as a binder and penetrates into the WC powder to form a strong bond. (4) After sintering, the pre-mold is naturally cooled to 350-360℃ in the high-temperature furnace, and then the pre-mold is taken out and cooled to room temperature.

2. The process for preparing a pre-mold for a metal wire drawing die according to claim 1, characterized in that, The filler is composed of the following components by volume percentage: WC 80%; Co 10%; Ni 5%; Cu 3%; Mn 1%; Si 1%.

3. The process for preparing a pre-mold for a metal wire drawing die according to claim 1, characterized in that, The filler is composed of the following components by volume percentage: WC 85%; Co 9%; Ni 2%; Cu 2%; Mn 1.5%; Si 0.5%.

4. The preparation process of the pre-mold for a metal wire drawing die according to claim 1, characterized in that, The sintering temperature is 850℃.

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