High-toughness nut for automobiles

Abstract

The application relates to the technical field of automobile fasteners, and discloses a high-toughness nut for an automobile, which comprises a nut body and a composite reinforcing layer; the nut body is made of low-carbon alloy structural steel and is subjected to forging-quenching and tempering treatment, so that the high-toughness nut body has high strength and high toughness and still has good impact resistance in a low-temperature environment; the carburized layer of the composite reinforcing layer and the zinc-nickel alloy plating layer have a synergistic effect, the wear resistance is significantly enhanced, the fine thread design increases the thread contact area, a cold work hardening layer formed by rolling and strengthening is matched, the thread sliding wire resistance is improved, the annular buffer groove can accommodate the deformation of a gasket, the connection reliability is further ensured, the overall structure is compact, the connection requirements of different parts such as an automobile chassis and an engine can be met by adjusting the thread specifications, the versatility is high, and the high-strength and high-reliability requirement of new energy vehicles for fasteners is especially met.

Description

Technical Field

[0001] This application relates to the technical field of automotive fasteners, and in particular to a high-toughness nut for automobiles. Background Technology

[0002] Nuts are core fasteners in automotive connections, and their performance directly affects the structural stability of the entire vehicle. During vehicle operation, nuts must withstand complex conditions such as vibration, impact, and temperature changes. Nuts in parts such as the chassis and engine are especially subjected to alternating loads for extended periods. If their toughness is insufficient, fatigue fracture or thread stripping can easily occur, leading to loose connections and potentially causing safety accidents.

[0003] Existing automotive nuts have certain shortcomings: traditional steel nuts (such as No. 45 steel) have high strength but poor toughness, and are prone to brittle fracture under low temperature environment or severe impact; some alloy nuts have improved toughness, but their strength has decreased significantly, their thread load-bearing capacity is insufficient, and they are prone to plastic deformation after long-term use; in addition, the thread surface of ordinary nuts has poor wear resistance, and the thread accuracy decreases after repeated disassembly and assembly, the mating clearance increases, and the connection stability is affected. Utility Model Content

[0004] To address the problems mentioned in the background art, this application provides a high-toughness nut for automobiles.

[0005] This application provides a high-toughness nut for automobiles, employing the following technical solution:

[0006] A high-toughness nut for automobiles includes a nut body and a composite reinforcing layer;

[0007] The nut body is made of low-carbon alloy structural steel through forging and tempering, and is in the shape of a hexagonal prism. A threaded hole is opened through the central axis of the nut body, and a fine thread is machined in the threaded hole.

[0008] The composite reinforcement layer is set on the surface of the nut body. The composite reinforcement layer includes a carburized layer and a zinc-nickel alloy plating layer. The outer surface of the nut body is subjected to carburizing and quenching treatment to form a 0.3-0.5mm carburized layer, which enhances wear resistance and corrosion resistance. A zinc-nickel alloy plating layer with a thickness of 8-12μm is sprayed on the outside of the carburized layer to adapt to the humid and dusty working environment of automobiles.

[0009] The nut body has multiple annular buffer grooves machined on one end face, which can accommodate the deformation of the washer during assembly and enhance the stability of the preload.

[0010] Preferably, the hexagonal edges of the hexagonal prism are rounded to reduce stress concentration.

[0011] Preferably, the fine thread surface is subjected to rolling strengthening treatment, forming a 0.1-0.2mm cold work hardening layer on the surface, which improves the thread wear resistance and anti-slipping ability.

[0012] In summary, this application includes the following beneficial technical effects:

[0013] Compared to existing technologies, this nut body is made of low-carbon alloy structural steel through forging and tempering, ensuring both high strength and high toughness. It maintains good impact resistance even at low temperatures. The carburized layer of the composite reinforcement layer and the zinc-nickel alloy plating work together to significantly enhance wear resistance. The fine thread design increases the thread contact area, and the work-hardened layer formed by rolling reinforcement improves the thread's anti-slip capability. The annular buffer groove can accommodate gasket deformation, further ensuring connection reliability. The overall structure is compact and can be adapted to the connection needs of different parts such as automobile chassis and engines by adjusting the thread specifications. It has strong versatility and is especially suitable for the high strength and high reliability requirements of fasteners in new energy vehicles. Attached Figure Description

[0014] Figure 1 This is a three-dimensional structural diagram of an embodiment of the application.

[0015] Explanation of reference numerals in the attached drawings: 1. Nut body; 2. Threaded hole; 3. Fine thread; 4. Annular buffer groove; 5. Composite reinforcement layer. Detailed Implementation

[0016] The following is in conjunction with the appendix Figure 1 This application will be described in further detail.

[0017] This application discloses a high-toughness nut for automobiles. (See also...) Figure 1 A high-toughness nut for automobiles includes a nut body 1 and a composite reinforcing layer 5;

[0018] The nut body 1 is made of low-carbon alloy structural steel through forging and tempering. It is hexagonal in shape, and the hexagonal edges are rounded to reduce stress concentration. A threaded hole 2 is opened through the central axis of the nut body 1. Fine thread 3 is machined in the threaded hole 2. The surface of the fine thread 3 is rolled and strengthened, and a cold work hardened layer of 0.1-0.2mm is formed on the surface to improve the wear resistance and anti-slipping ability of the thread.

[0019] The composite reinforcement layer 5 is set on the surface of the nut body 1. The composite reinforcement layer 5 includes a carburized layer and a zinc-nickel alloy plating layer. The outer surface of the nut body 1 is subjected to carburizing and quenching treatment to form a 0.3-0.5mm carburized layer, which enhances wear resistance and corrosion resistance. A zinc-nickel alloy plating layer with a thickness of 8-12μm is sprayed on the outside of the carburized layer to adapt to the humid and dusty working environment of automobiles.

[0020] Multiple annular buffer grooves 4 are machined on one end face of the nut body 1, which can accommodate the deformation of the washer during assembly and enhance the stability of the preload.

[0021] The implementation principle of a high-toughness nut for automobiles according to an embodiment of this application is as follows: The nut body 1 is made of low-carbon alloy structural steel through forging and tempering to form a matrix with both high strength and high toughness. Its hexagonal prism structure facilitates tool loading and unloading. The fine thread 3 in the central threaded hole 2 mates with the bolt, and the mechanical engagement between the threads achieves initial fixation. The design of the fine thread 3 increases the thread contact area, making the load distribution more uniform and reducing local stress concentration. In the composite reinforcement layer 5, the carburized layer is formed on the outer surface of the nut body 1 through carburizing and quenching treatment, which improves the surface hardness and wear resistance, ensuring that the thread structure of the nut is not easily worn during repeated disassembly and assembly. The zinc-nickel alloy plating layer outside the carburized layer forms a dense protective film, isolating moisture, dust and other corrosive media, preventing the body from rusting, and adapting to the humid and dusty working environment of automobiles. During assembly, the annular buffer groove 4 on one end face of the nut body 1 can accommodate the slight deformation of the washer under the preload, allowing the preload to be transmitted more evenly to the connected parts and reducing the loss of preload due to washer deformation. The rounded corners of the hexagonal edges further reduce stress concentration during assembly and use, preventing cracks from forming on the edges due to impacts or vibrations. During vehicle operation, when subjected to alternating loads such as vibration and impact, the high toughness of the low-carbon alloy matrix can absorb energy and prevent brittle fracture. The surface layer of the rolled fine thread 3 is cold-worked to improve anti-slip capability and ensure the stability of the thread fit. The composite reinforcement layer 5 continuously provides wear resistance and corrosion protection, ensuring the long-term performance of the nut.

[0022] In this process, the nut body 1 is made of low-carbon alloy structural steel and is forged and tempered to ensure high strength and high toughness. It can still maintain good impact resistance in low-temperature environments. The carburized layer of the composite reinforcement layer 5 and the zinc-nickel alloy plating work together to significantly enhance wear resistance. The fine thread 3 design increases the thread contact area. Combined with the cold work hardening layer formed by rolling reinforcement, it improves the thread anti-slip capability. The annular buffer groove 4 can accommodate the deformation of the gasket and further ensure the reliability of the connection. The overall structure is compact and can be adapted to the connection needs of different parts such as automobile chassis and engine by adjusting the thread specifications. It has strong versatility and is especially suitable for the high strength and high reliability requirements of fasteners in new energy vehicles.

[0023] Finally, the following points should be noted: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection", and "linkage" should be interpreted broadly, and can be mechanical or electrical connections, or internal connections between two components, or direct connections. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may change.

[0024] Secondly: The accompanying drawings of the embodiments disclosed in this utility model only involve the structures involved in the embodiments disclosed in this utility model. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this utility model can be combined with each other.

[0025] Finally: The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

[0026] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A high-toughness nut for automobiles, characterized by: It includes a nut body (1) and a composite reinforcing layer (5); The nut body (1) is made of low carbon alloy structural steel by forging and tempering, and is in the shape of a hexagonal prism. A screw hole (2) is provided through the central axis of the nut body (1), and a fine thread (3) is machined in the screw hole (2). The composite reinforcement layer (5) is disposed on the surface of the nut body (1). The composite reinforcement layer (5) includes a carburized layer and a zinc-nickel alloy plating layer. The outer surface of the nut body (1) is subjected to carburizing and quenching treatment to form a carburized layer of 0.3-0.5mm, which enhances the wear resistance and corrosion resistance. A zinc-nickel alloy plating layer with a thickness of 8-12μm is sprayed on the outside of the carburized layer to adapt to the humid and dusty working environment of automobiles. The nut body (1) has multiple annular buffer grooves (4) machined on one end face, which can accommodate the deformation of the gasket during assembly and enhance the stability of the preload.

2. A high ductility nut for automotive use according to claim 1, characterized in that: The hexagonal edges of the hexagonal prism are rounded to reduce stress concentration.

3. A high ductility nut for automotive use according to claim 1, characterized in that: The fine thread (3) is subjected to rolling reinforcement treatment, and a cold work hardening layer of 0.1-0.2mm is formed on the surface to improve the thread wear resistance and anti-slipping ability.

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