Fine cold-drawn polished spring flat steel for automotive suspension

Abstract

The utility model discloses fine cold-drawn polished spring flat steel for an automobile suspension. The fine cold-drawn polished spring flat steel comprises a flat steel body, a groove, a protective layer, a metal corrosion-resistant layer and an organic compact coating, the edge of the section of the flat steel body is in continuous arc transition, the arc radius is increased in a gradient mode in the thickness direction, and a stress dispersion area with the thick center and the thin edge is formed. At least two symmetrically-distributed grooves are formed in the surface of the flat steel body in the length direction, and the cross section of each groove is of a semicircular structure; the flat steel comprises a flat steel body, the surface of the flat steel body is covered with a protective layer, the protective layer comprises a metal corrosion-resistant layer and an organic compact coating, the metal corrosion-resistant layer is located on the surface of the flat steel body, the organic compact coating is located on the surface of the metal corrosion-resistant layer, a hollow cavity is formed in the flat steel body, a reinforcing structure is arranged in the hollow cavity, and the reinforcing structure is arranged in the hollow cavity. The corrosion resistance of the flat steel body can be improved, the service life of the flat steel body is prolonged, and meanwhile the requirements for high bearing capacity and impact resistance are met.

Description

Technical Field

[0001] This utility model relates to the technical field of flat steel, and in particular to the technical field of precision cold-drawn bright spring flat steel for automobile suspension. Background Technology

[0002] Spring flat steel is mainly used to manufacture various springs and elastic elements. Specifically, spring flat steel is widely used in machinery such as automobiles, tractors, and railway transportation, especially in automobile suspensions as leaf springs, which play the roles of buffering, vibration reduction, and force transmission.

[0003] Currently, the rolling process for spring flat steel is quite complex. Stress concentration occurs at the corners within the groove during rolling, which can easily lead to cracks. The steel is also prone to chipping during shearing, resulting in a low yield rate.

[0004] To address the problems mentioned above, for example, application number CN201420204689.5 discloses a spring flat steel, including a flat steel body. Two grooves are evenly spaced along the length of the flat steel body on the top surface of the outer edge. A groove is also provided in the middle of the bottom surface of the flat steel body along the length of the flat steel body. The cross-section of the three grooves is semi-circular. Both sides of the flat steel body are arc-shaped. The advantages are that the grooves are arc-shaped, there are no included angles in the grooves, there is no stress concentration problem, and the problems of cracks at included angles and easy material breakage during shearing are avoided. The yield of rolled steel is high.

[0005] For example, application number CN201620543459.0 discloses a spring flat steel body, which includes a tension surface, a compression surface, and a neutral layer. The neutral layer is located inside the steel body and is biased towards the tension surface. Two grooves of No. 1 are evenly distributed and spaced along the length of the steel body on the top surface of the outer edge of the steel body, and a groove of No. 2 is provided in the middle of the bottom surface of the steel body along the length of the steel body. The cross-section of grooves No. 1 and No. 2 is semi-circular. In this invention, because the grooves are arc-shaped and there are no included angles in the grooves, there is no stress concentration problem, avoiding the problems of cracks at included angles and easy material breakage during shearing, resulting in a high yield of rolled steel.

[0006] However, all of the above structures have the following drawbacks:

[0007] 1. The above structure has poor corrosion resistance. Spring flat steel is prone to corrosion in humid and salt spray environments for a long time, which reduces its service life.

[0008] 2. The overall strength of the above structure is relatively low, making it difficult to meet the requirements for high load-bearing capacity and impact resistance. Summary of the Invention

[0009] The purpose of this invention is to solve the problems in the prior art by proposing a precision cold-drawn flat spring steel for automotive suspension, which can improve the corrosion resistance of the flat steel body, extend its service life, and meet the requirements of high load-bearing capacity and impact resistance.

[0010] To achieve the above objectives, this utility model proposes a precision cold-drawn bright spring flat steel for automotive suspension, comprising a flat steel body, grooves, a protective layer, a metal corrosion-resistant layer, and an organic dense coating; the edge of the flat steel body cross-section has a continuous arc transition, and the radius of the arc gradually increases along the thickness direction, forming a stress dispersion zone that is thick at the center and thin at the edges; the surface of the flat steel body is provided with at least two symmetrically distributed grooves along the length direction, and the cross-section of the grooves is a semi-circular structure; the surface of the flat steel body is covered with a protective layer, which includes a metal corrosion-resistant layer and an organic dense coating, wherein the metal corrosion-resistant layer is located on the surface of the flat steel body, and the organic dense coating is located on the surface of the metal corrosion-resistant layer.

[0011] Preferably, the flat steel body has a hollow cavity inside, and a reinforcing structure is provided inside the hollow cavity. The reinforcing structure includes a plurality of reinforcing ribs and reinforcing ribs. The plurality of reinforcing ribs are arranged along the length of the flat steel body, and the reinforcing ribs are generally arched. Each reinforcing rib has a reinforcing rib on its inner side. The reinforcing rib is generally in the shape of a star, and the end of the reinforcing rib abuts against the inner wall of the reinforcing rib.

[0012] Preferably, the surface of the groove is machined with a number of pits, which are spaced apart along the length of the flat steel body. The depth of the pits is less than the depth of the groove, and a corrosion inhibitor filling layer is pre-placed in the pits.

[0013] Preferably, the end of the flat steel body is provided with a U-shaped sealing groove, the groove direction is perpendicular to the length direction of the flat steel body, and the inner wall of the groove is provided with an elastic sealing strip fitting structure.

[0014] Preferably, the flat steel body has several water guide grooves on both sides, and the water guide grooves are distributed at intervals along the length of the flat steel body.

[0015] Preferably, the cross-section of the water guide channel has a U-shaped structure.

[0016] The beneficial effects of this utility model are:

[0017] 1. This utility model provides sacrificial anode protection for the flat steel body by setting a metal corrosion-resistant layer (such as nickel-based alloy), physically isolates the corrosive medium by setting an organic dense coating (such as epoxy resin), and at the same time, the pits serve as corrosion inhibitor storage units. The corrosion inhibitor (such as nitrite) seeps out through the micro-cracks of the coating and preferentially adsorbs on the metal surface to form a protective film, thereby further improving the corrosion resistance of the flat steel body. This makes the flat steel body less susceptible to corrosion in humid and salt spray environments, thus extending the service life of the flat steel body.

[0018] 2. By setting up a reinforcement structure, this utility model can improve the overall strength of the flat steel body. When the arched reinforcing rib plate is under pressure, the pressure will be transmitted downward and outward along the arched structure to the adjacent parts, forming a horizontal outward thrust. This dispersion method avoids stress concentration and makes the pressure evenly distributed on the entire surface of the structure. At the same time, the arched reinforcing rib plates are squeezed together when under pressure, and the combination is more compact, thereby enhancing the overall stability. In addition, there are cross-shaped reinforcing rib columns on the inner side of the reinforcing rib plate, which can provide strong support for the reinforcing rib plate, thereby further improving the overall compressive strength of the flat steel body. Attached Figure Description

[0019] Figure 1 This is the front view of the precision cold-drawn flat steel for automotive suspension according to this utility model;

[0020] Figure 2 This is an internal cross-sectional view of the precision cold-drawn bright flat steel for automotive suspension according to this utility model;

[0021] Figure 3 This is a top view of the precision cold-drawn flat steel for automotive suspension according to this utility model;

[0022] Figure 4 This is a cross-sectional view of the precision cold-drawn bright spring flat steel for automotive suspension according to this utility model;

[0023] In the diagram: 1-Flat steel body, 2-Groove, 3-Protective layer, 301-Metal corrosion resistant layer, 302-Organic dense coating, 4-Hollow cavity, 5-Reinforced structure, 501-Reinforcing rib plate, 502-Reinforcing rib column, 6-Pit, 7-Slot, 8-Elastic sealing strip fitting structure, 9-Water guide groove. Detailed Implementation

[0024] See Figures 1 to 4This utility model discloses a precision cold-drawn bright spring flat steel for automotive suspension, comprising a flat steel body 1, grooves 2, a protective layer 3, a metal corrosion-resistant layer 301, and an organic dense coating 302. The flat steel body 1 has a continuous arc-shaped transition at its cross-sectional edge, with the arc radius gradually increasing along the thickness direction, forming a stress dispersion zone that is thicker at the center and thinner at the edges. The surface of the flat steel body 1 has at least two symmetrically distributed grooves 2 along its length, and the cross-section of each groove 2 is semi-circular. The surface of the flat steel body 1 is covered with the protective layer 3, which includes the metal corrosion-resistant layer 301. The metal corrosion-resistant layer 301 is located on the surface of the flat steel body 1, and the organic dense coating 302 is located on the surface of the metal corrosion-resistant layer 301. The arc transition replaces the traditional right angle, disperses stress concentration, and reduces the probability of crack initiation. The groove 2 guides the stress to be uniformly transmitted along the length of the flat steel body 1, avoiding local stress overload. The metal corrosion-resistant layer 301 (such as nickel-based alloy) can provide sacrificial anode protection for the flat steel body 1, and the organic dense coating 302 (such as epoxy resin) physically isolates the corrosive medium.

[0025] See Figure 2 The flat steel body 1 has a hollow cavity 4 inside, and a reinforcing structure 5 is provided inside the hollow cavity 4. The reinforcing structure 5 includes a plurality of reinforcing ribs 501 and reinforcing ribs 502. The plurality of reinforcing ribs 501 are arranged along the length direction of the flat steel body 1, and the reinforcing ribs 501 are generally arched. Each reinforcing rib 501 has a reinforcing rib 502 on its inner side. The reinforcing ribs 502 are generally in a star-shaped structure, and the end of the reinforcing rib 502 abuts against the inner wall of the reinforcing rib 501. When the arched reinforcing rib plate 501 is subjected to pressure, the pressure is transmitted downward and outward along the arched structure to adjacent parts, forming a horizontal outward thrust. This dispersion method avoids stress concentration and makes the pressure evenly distributed on the entire surface of the structure. At the same time, the arched reinforcing rib plates 501 are squeezed together when under pressure, and the combination is more compact, thereby enhancing the overall stability. Furthermore, the inner side of the reinforcing rib plate 501 is provided with a star-shaped reinforcing rib column 502, which can provide strong support for the reinforcing rib plate 501, thereby further improving the overall compressive strength of the flat steel body 1.

[0026] See Figure 3 The surface of the groove 2 is processed with a number of pits 6. The pits 6 are distributed at intervals along the length of the flat steel body 1. The depth of the pits 6 is less than the depth of the groove 2, and a corrosion inhibitor filling layer is pre-placed in the pits 6. The pits 6 serve as corrosion inhibitor storage units. The corrosion inhibitor (such as nitrite) seeps out through the microcracks in the coating and preferentially adsorbs onto the metal surface to form a protective film, thereby further improving the corrosion resistance of the flat steel body 1.

[0027] See Figure 1The end of the flat steel body 1 is provided with a U-shaped sealing groove 7. The direction of the groove 7 is perpendicular to the length direction of the flat steel body 1, and the inner wall of the groove 7 is provided with an elastic sealing strip fitting structure 8. When installed, a rubber or silicone sealing strip 8 is embedded, and the elastic material deformation fills the gap between the end of the flat steel and the adjacent parts to block water vapor penetration.

[0028] See Figure 1 The flat steel body 1 has several water guide grooves 9 on both sides. The water guide grooves 9 are distributed at intervals along the length of the flat steel body 1, so that water is not easy to stay on the flat steel body 1 and can be discharged downward through the water guide grooves 9.

[0029] See Figure 1 The cross-section of the water guide channel 9 has a concave shape.

[0030] The working process of this utility model:

[0031] In the operation of this utility model, the precision cold-drawn flat spring steel for automotive suspension provides sacrificial anode protection for the flat steel body 1 by setting a metal corrosion-resistant layer 301 (such as a nickel-based alloy), physically isolating the corrosive medium by setting an organic dense coating 302 (such as an epoxy resin), and using the pits 6 as corrosion inhibitor storage units, the corrosion inhibitor (such as nitrite) seeps out through the micro-cracks of the coating and preferentially adsorbs on the metal surface to form a protective film, thereby further improving the corrosion resistance of the flat steel body 1.

[0032] When the arched reinforcing rib plate 501 is subjected to pressure, the pressure is transmitted downward and outward along the arched structure to adjacent parts, forming a horizontal outward thrust. This dispersion method avoids stress concentration and makes the pressure evenly distributed across the entire structural surface. At the same time, the arched reinforcing rib plates 501 are squeezed together under pressure, making them more tightly bonded, thereby enhancing the overall stability. Furthermore, the inner side of the reinforcing rib plate 501 is provided with a star-shaped reinforcing rib column 502, which can provide strong support for the reinforcing rib plate 501, thereby further improving the overall compressive strength of the flat steel body 1.

[0033] The above embodiments are illustrative of the present invention and are not intended to limit the present invention. Any simple modifications to the present invention are within the protection scope of the present invention.

Claims

1. Precision cold-drawn bright flat steel for automotive suspension, characterized in that: The structure includes a flat steel body (1), a groove (2), a protective layer (3), a metal corrosion-resistant layer (301), and an organic dense coating (302). The flat steel body (1) has a continuous arc-shaped transition at the edge of its cross section, and the radius of the arc increases gradually along the thickness direction, forming a stress dispersion zone that is thick at the center and thin at the edge. The surface of the flat steel body (1) is provided with at least two symmetrically distributed grooves (2) along the length direction, and the cross section of the grooves (2) is a semi-circular structure. The surface of the flat steel body (1) is covered with a protective layer (3), which includes a metal corrosion-resistant layer (301) and an organic dense coating (302). The metal corrosion-resistant layer (301) is located on the surface of the flat steel body (1), and the organic dense coating (302) is located on the surface of the metal corrosion-resistant layer (301).

2. The precision cold-drawn flat spring steel for automotive suspension as described in claim 1, characterized in that: The flat steel body (1) has a hollow cavity (4) inside, and a reinforcing structure (5) is provided inside the hollow cavity (4). The reinforcing structure (5) includes several reinforcing ribs (501) and reinforcing ribs (502). The several reinforcing ribs (501) are arranged along the length of the flat steel body (1), and the reinforcing ribs (501) are generally arched. Each reinforcing rib (501) has a reinforcing rib (502) on its inner side. The reinforcing rib (502) is generally in the shape of a star, and the end of the reinforcing rib (502) abuts against the inner wall of the reinforcing rib (501).

3. The precision cold-drawn flat spring steel for automotive suspension as described in claim 1, characterized in that: The surface of the groove (2) is processed with a number of pits (6). The pits (6) are distributed at intervals along the length of the flat steel body (1). The depth of the pits (6) is less than the depth of the groove (2), and a corrosion inhibitor filling layer is pre-placed in the pits (6).

4. The precision cold-drawn flat spring steel for automotive suspension as described in claim 1, characterized in that: The end of the flat steel body (1) is provided with a U-shaped sealing groove (7), the direction of the groove (7) is perpendicular to the length direction of the flat steel body (1), and the inner wall of the groove (7) is provided with an elastic sealing strip fitting structure (8).

5. The precision cold-drawn flat spring steel for automotive suspension as described in claim 1, characterized in that: The flat steel body (1) has several water guide grooves (9) on both sides, and the water guide grooves (9) are distributed at intervals along the length direction of the flat steel body (1).

6. The precision cold-drawn flat spring steel for automotive suspension as described in claim 5, characterized in that: The cross-section of the water guide channel (9) is U-shaped.

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