Springs, spring processing technology and vehicles

Abstract

This invention discloses a spring, a spring processing technology, and a vehicle. The spring comprises: a wire substrate with a circular cross-section; an oxide layer covering the surface of the wire substrate; an aluminum-silicon coating covering the outer surface of the oxide layer, wherein the mass percentages of the components in the aluminum-silicon coating are: Al: 80%-92%, Si≥8%, and the remainder being Fe; and an electrophoretic layer covering the outer surface of the aluminum-silicon coating. According to the spring of this invention, by coating the outer surface of the wire substrate with a dense oxide layer, the adhesion of the coating is improved. Furthermore, by coating the outer surface of the oxide layer with an aluminum-silicon coating, the corrosion resistance and high-temperature resistance of the spring are improved. This reduces the occurrence of oxide scale and decarburized layers during the heating process, thereby reducing the need for shot peening to remove surface oxide scale, improving work efficiency, and providing environmental benefits.

Description

Technical Field

[0001] This invention relates to the field of spring manufacturing technology, and in particular to a spring, a spring processing technology, and a vehicle. Background Technology

[0002] Related technologies indicate that with the development of lightweight automobiles, the strength requirements for helical springs, as load-bearing safety components, are constantly increasing, leading to a greater risk of fracture. Therefore, controlling surface defects and corrosion failures in materials is particularly important. In existing technologies, some automotive helical springs are made from unplated, coarse-diameter raw materials supplied by steel mills. These materials are drawn to a suitable spring wire diameter, and then undergo a series of processes such as surface cleaning and vapor oxidation to obtain the spring wire. Subsequently, a spring coiling process is performed, which can be either cold coiling or hot coiling.

[0003] Regardless of the method, the automotive springs currently manufactured all use unplated wire. During the hot rolling and quenching process, the high temperature will cause surface oxidation, increase the oxide scale, and lead to surface decarburization, which will reduce the surface strength and fatigue performance. The increase of oxide scale caused by hot rolling is particularly obvious, and a shot peening process is required to remove the oxide scale.

[0004] With the increasing volume of automobiles exported overseas and the increasing complexity of their operating environments, higher demands are being placed on corrosion resistance. In the aforementioned solution, corrosion resistance is ensured through electrophoretic coating after the finished product is manufactured. However, because the spring body material is uncoated, it is prone to corrosion failure in harsh environments, especially under complex overseas operating conditions. Furthermore, the spring substrate reaches temperatures as high as 900–1000℃ during heating, causing surface oxidation and increasing oxide scale buildup, requiring more frequent cleaning and reducing production efficiency. Oxidation of the wire during high-temperature heating leads to surface decarburization, reducing surface hardness and fatigue life. Summary of the Invention

[0005] The present invention aims to at least solve one of the technical problems existing in the prior art. To this end, the present invention provides a spring with good corrosion resistance.

[0006] The present invention also proposes a processing technology for springs.

[0007] The present invention also proposes a vehicle.

[0008] According to a first aspect of the present invention, a spring comprises: a wire substrate having a circular cross-section; an oxide layer covering the surface of the wire substrate; an aluminum-silicon coating covering the outer surface of the oxide layer, wherein the mass percentages of the components in the aluminum-silicon coating are: Al: 80%-92%, Si≥8%, and the remainder being Fe; and an electrophoretic layer covering the outer surface of the aluminum-silicon coating.

[0009] According to the spring of the present invention, by coating the outer surface of the wire substrate with a dense oxide layer, the adhesion of the coating is improved, and by coating the outer side of the oxide layer with an aluminum-silicon coating, the corrosion resistance and high temperature resistance of the spring are improved, and the occurrence of oxide scale and decarburized layer during the heating process is reduced, thereby reducing the need for shot peening to remove the oxide scale from the surface, improving work efficiency and having an environmental protection effect.

[0010] In some embodiments, the thickness of the aluminum-silicon coating is in the range of 30μm-45μm, and the microstructure of the aluminum-silicon coating is: α-Fe, Fe-Al layer binary alloy phase, Fe-Al-Si layer ternary alloy τ5 phase, Fe-Al layer binary alloy phase.

[0011] In some embodiments, the mass percentages of each component in the wire matrix are: C: 0.51%-0.63%, Si: 1.20%-1.60%, Mn: 0.35%-0.80%, P≤0.030%, S≤0.030%, Cr: 0.40%-0.80%.

[0012] In some embodiments, the diameter of the wire substrate is in the range of 10mm-25mm.

[0013] According to the processing technology of the spring according to the second aspect of the present invention, for producing the spring according to the first aspect of the present invention, the processing technology includes:

[0014] Step S1: Based on the design requirements and CAE analysis results, determine the wire diameter, strength, material grade, and shape of the spring;

[0015] Step S2: Select a suitable wire diameter raw material and modify the wire diameter of the raw material;

[0016] Step S3: Coil the modified wire into a spring;

[0017] The modification of the wire diameter of the raw material in step S2 includes at least the following: sequential induction heating, pre-oxidation, and hot-dip aluminum-silicon plating of the raw material.

[0018] According to the processing technology of the spring of the present invention, during the modification of the wire substrate, steam surface oxidation is carried out to form a dense oxide layer, which plays an isolation role and improves the adhesion of corrosion protection and coating. In addition, during the modification of raw materials, the surface of the wire substrate is hot-dip aluminum-silicon coated. The heat resistance and corrosion resistance of the aluminum-silicon coating can ensure that decarburization of the spring and oxide scale peeling are reduced during subsequent heating. At the same time, the aluminum-silicon coating can significantly improve the corrosion resistance of the spring.

[0019] Furthermore, the temperature of the first induction heating wire is in the range of 550℃-650℃, and the heating time of the first induction heating wire is in the range of 20min-40min.

[0020] Furthermore, the temperature of the hot-dip aluminized silicon is in the range of 635℃-685℃, and the hot-dip aluminized silicon time is in the range of 5s-15s.

[0021] Furthermore, the hot-dip aluminum-silicon plating includes: hot-dip plating followed by air cooling, wherein the air cooling rate is in the range of 10℃ / s-30℃ / s.

[0022] Furthermore, before the first induction heating, the raw materials are sequentially straightened, shot-peened, drawn, and cleaned. After the hot-dip aluminized silicon coating, the raw materials are sequentially subjected to flaw detection and color marking.

[0023] Further, step S3 includes: sequentially performing second induction heating, quenching, tempering, coiling, annealing, shot peening, and surface spraying on the wire substrate, wherein the second induction heating temperature of the wire substrate is in the range of 880℃-950℃, the quenching temperature is in the range of 880℃-950℃, the tempering temperature is in the range of 400℃-450℃, and the annealing temperature is in the range of 170℃-250℃.

[0024] Further, step S3 includes: sequentially performing second induction heating, spring coiling, quenching, tempering, shot peening, and surface spraying on the wire substrate, wherein the second induction heating temperature of the wire substrate is in the range of 900℃-950℃, the temperature of the spring before quenching is not less than 850℃, and the tempering temperature is in the range of 400℃-450℃.

[0025] The vehicle according to a third aspect of the invention includes the spring according to the first aspect described above.

[0026] According to the present invention, by providing the spring described in the first aspect, the overall performance of the vehicle is improved and the service life of the vehicle is extended.

[0027] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the cross-section of the wire of the spring according to a first aspect embodiment of the present invention;

[0029] Figure 2 This is a schematic diagram of a spring according to a first aspect embodiment of the present invention;

[0030] Figure 3a yes Figure 1 Metallographic photograph of the wire before heating is shown;

[0031] Figure 3b yes Figure 1 Metallographic photograph of the wire after heating;

[0032] Figure 4a This is a metallographic photograph of a wire without an aluminum-silicon coating before heating.

[0033] Figure 4b This is a metallographic photograph of a wire without an aluminum-silicon coating after heating.

[0034] Figure 5 This is a process flow diagram of the spring according to the second embodiment of the present invention.

[0035] Figure label:

[0036] 100. Spring; 1. Wire substrate; 2. Oxide layer; 3. Aluminum-silicon coating; 4. Electrophoretic layer. Detailed Implementation

[0037] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0038] Reference below Figures 1-2 A spring 100 according to an embodiment of the first aspect of the present invention is described.

[0039] like Figure 1 As shown, the spring 100 according to a first aspect embodiment of the present invention includes: a wire substrate 1, an oxide layer 2, an aluminum-silicon plating layer 3, and an electrophoretic layer 4.

[0040] Specifically, the cross-section of the wire substrate 1 is circular. An oxide layer 2 is applied to the surface of the wire substrate 1, increasing its surface roughness. An aluminum-silicon coating 3 is applied to the outer surface of the oxide layer 2. The aluminum-silicon coating 3 is heat-resistant and will not peel off during heating. The mass percentages of the components in the aluminum-silicon coating 3 are: Al: 80%-92%, Si≥8%, with the remainder being Fe. An electrophoretic layer 4 is applied to the outer surface of the aluminum-silicon coating 3. Therefore, the component content of the aluminum-silicon coating 3 differs from existing technologies. Before thermoforming, the aluminum-silicon coating 3 forms two metallographic structures: an α-Al + Fe-Al-Si ternary alloy τ5 phase. After heat treatment, the aluminum-silicon coating 3 forms four metallographic structures: an α-Fe, a Fe-Al binary alloy phase, a Fe-Al-Si ternary alloy τ5 phase, and a Fe-Al binary alloy phase.

[0041] According to an embodiment of the present invention, the spring 100 improves the adhesion of the coating by coating a dense oxide layer 2 on the outer surface of the wire substrate 1, and further improves the corrosion resistance and high-temperature resistance of the spring 100 by coating an aluminum-silicon coating 3 on the outer side of the oxide layer 2. This reduces the occurrence of oxide scale and decarburization during the heating process, thereby reducing the need for shot peening to remove the oxide scale, improving work efficiency and having an environmentally friendly effect. Moreover, after heat treatment, the aluminum-silicon coating 3 undergoes interdiffusion, increasing its thickness to a range of 30μm-45μm and having a four-layer structure (α-Fe, Fe-Al binary alloy phase, Fe-Al-Si ternary alloy τ5 phase, and Fe-Al binary alloy phase). The Fe-Al-Si ternary alloy τ5 phase alloy layer has excellent corrosion resistance, improving the corrosion resistance of the spring 100. Simultaneously, it protects the wire substrate 1 from oxide scale and decarburization during heating, further improving work efficiency.

[0042] In some embodiments of the present invention, the mass percentages of each component in the wire matrix 1 are as follows: C: 0.51%-0.63%, Si: 1.20%-1.60%, Mn: 0.35%-0.80%, P≤0.030%, S≤0.030%, Cr: 0.40%-0.80%.

[0043] Furthermore, the diameter of the wire substrate 1 is in the range of 10mm-25mm, and the tensile strength of the spring 100 is in the range of 1250MPa-2050MPa.

[0044] The processing technology of the spring 100 according to the second aspect embodiment of the present invention is used to produce the spring 100 according to the first aspect embodiment of the present invention described above.

[0045] Specifically, the processing technology includes:

[0046] Step S1: Based on the design requirements and CAE analysis results, determine the wire diameter, strength, material grade, and shape of the spring;

[0047] Step S2: Select a suitable wire substrate and modify the wire substrate;

[0048] Step S3: Coil the modified wire substrate into a spring;

[0049] The modification of the wire substrate in step S2 includes at least the following: sequential induction heating, pre-oxidation, and hot-dip aluminum-silicon plating of the wire substrate.

[0050] According to the processing technology of the spring 100 of the present invention, during the modification process of the wire substrate 1, water vapor surface oxidation is carried out to form a dense oxide layer 2, which plays an isolation role and improves the adhesion of corrosion protection and coating. In addition, during the modification process of raw materials, the surface of the wire substrate 1 is hot-dip aluminum-silicon coated. The heat resistance and corrosion resistance of the aluminum-silicon coating 3 can ensure that the decarburization of the spring 100 and the peeling off of the oxide scale are reduced during the subsequent heating process. At the same time, the aluminum-silicon coating 3 can significantly improve the corrosion resistance of the spring 100.

[0051] Furthermore, the temperature of the first induction heating wire is in the range of 550℃-650℃, and the time of the first induction heating wire is in the range of 20min-40min. For example, the temperature of the first induction heating can be: 550℃, 560℃, 570℃, 580℃, 590℃, 600℃, 610℃, 620℃, 630℃, 640℃, 650℃, etc.; the time of the first induction heating can be 20min, 21min, 22min, 23min, 24min, 25min, 26min, 27min, 28min, 29min, 30min, 31min, 32min, 33min, 34min, 35min, 36min, 37min, 38min, 39min, 40min, etc.

[0052] Preferably, the first induction heating time is 30 minutes.

[0053] Furthermore, the temperature for hot-dip aluminizing silicon is within the range of 635℃-685℃, and the hot-dip aluminizing silicon time is within the range of 5s-15s. For example, the hot-dip aluminizing silicon temperature can be 635℃, 640℃, 645℃, 650℃, 655℃, 660℃, 665℃, 670℃, 675℃, 680℃, 685℃, etc.; the hot-dip aluminizing silicon time can be 5s, 6s, 7s, 8s, 9s, 10s, 11s, 12s, 13s, 14s, 15s, etc.

[0054] In some embodiments of the present invention, hot-dip aluminum-silicon plating includes sequential hot-dip plating and air cooling, wherein the air cooling rate is in the range of 10°C / s to 30°C / s. For example, the air cooling rate can be 10°C / s, 15°C / s, 20°C / s, 25°C / s, 30°C / s, etc.

[0055] Furthermore, before the first induction heating, the wire substrate 1 is sequentially straightened, shot-peened, drawn, and cleaned. After hot-dip aluminized silicon plating, the wire substrate 1 is sequentially inspected for flaws and marked with color marks. The modification process in step S2 is as follows: raw material → straightening → shot peening → drawing → cleaning → first induction heating (water vapor surface oxidation) → hot-dip aluminized silicon plating → flaw inspection → color marking.

[0056] Specifically, the temperature of the first induction heating is 550-650℃, and the time is controlled at approximately 30 minutes according to the wire feeding speed. Simultaneously, saturated water vapor is sprayed onto the surface of the wire substrate 1, forming a dense Fe3O4 oxide layer 2. This oxide layer 2 increases surface roughness, improving adhesion during the subsequent aluminum-silicon plating process. Furthermore, the dense oxide layer 2 provides good isolation and barrier properties, enhancing the wire's corrosion resistance. During the hot-dip aluminum-silicon plating process, the temperature of the plating bath is 635-685℃, the plating composition is Al: 80%-92%, Si≥8%, and the remainder is Fe. The time spent in the plating bath is 5-15 seconds, followed by air cooling at a rate of 10℃ / s-30℃ / s. This yields a wire substrate 1 with an aluminum-silicon plating layer 3 (plating structure: α-Al+Fe-Al-Si layer ternary alloy τ5 phase, thickness approximately 20-30μm). Afterward, flaw detection and color marking (e.g., ...) are performed. Figure 1 and Figure 3a (as shown);

[0057] In some embodiments of the present invention, step S3 includes: sequentially performing second induction heating, quenching, tempering, coiling, annealing, shot peening, and surface spraying on the wire substrate 1, wherein the second induction heating temperature of the wire substrate 1 is in the range of 880℃-950℃, the quenching temperature is in the range of 880℃-950℃, the tempering temperature is in the range of 400℃-450℃, and the annealing temperature is in the range of 170℃-250℃.

[0058] Specifically, the coiling spring process is as follows: second induction heating → quenching → tempering → coiling → annealing → shot peening → surface spraying. Before quenching, the wire substrate 1 undergoes a second induction heating at a temperature between 880℃ and 950℃. The quenching temperature is also between 880℃ and 950℃. That is, the wire substrate 1 is subjected to the second induction heating to the required quenching temperature before quenching. Oil quenching or water quenching can be used. The tempering temperature is set between 400℃ and 450℃, resulting in a tempered martensite structure in the wire substrate 1. During the quenching and tempering process, the basic mechanical properties of the wire substrate 1 are improved. Simultaneously, the aluminum-silicon coating 3 on the surface undergoes an alloying process, increasing its thickness to between 30μm and 45μm. The annealing temperature is 170℃ to 250℃, eliminating stress during the coiling process. Shot peening enhances the compressive stress on the surface of the spring 100. That is, the spring coiling process of spring 100 is cold coiling, which is completed at room temperature.

[0059] In some other embodiments of the present invention, step S3 includes: sequentially performing second induction heating, spring coiling, quenching, tempering, shot peening, and surface spraying on the wire substrate 1, wherein the second induction heating temperature of the wire substrate 1 is in the range of 900℃-950℃, the temperature of the spring 100 before quenching is not less than 850℃, and the tempering temperature is in the range of 400℃-450℃.

[0060] Specifically, the spring coiling process is as follows: second induction heating → spring coiling → quenching → tempering → shot peening → surface spraying. The wire substrate 1 is heated to a temperature range of 900℃-950℃, causing the aluminum-silicon coating 3 on the surface to alloy, increasing its thickness to between 30μm and 45μm. Following this, the spring coiling process is performed. After coiling, the residual heat is used for quenching, controlling the temperature of the spring 100 before entering the quenching tank to be ≥850℃. The tempering temperature is set between 400℃ and 450℃. Surface spraying is then performed. Compared to traditional processes, a descaling process is not required after quenching and tempering. In other words, the spring coiling process of the spring 100 is hot coiling, completed at a temperature greater than 850℃.

[0061] The following will refer to Figures 1-5 The manufacturing process of the spring 100 according to two specific embodiments of the present invention is described.

[0062] Example 1,

[0063] 16mm diameter 54SiCr6 wire rod was shot-peened (to a strength of approximately 0.2Amm-0.3Amm) to remove surface oil and oxide scale. Subsequently, it was drawn to obtain a 14mm diameter wire substrate 1. The surface drawing powder was then cleaned with a brush, followed by high-frequency induction heating (100kHz, 630℃, approximately 20min). Simultaneously, supersaturated steam was introduced at a flow rate of 12L / min, forming a dense oxide layer 2 on the surface and increasing surface roughness. The wire substrate 1 is hot-dip plated in a plating bath (10 seconds, 650°C, composition of Al: 89%, Si: 9%, with the remainder being Fe), followed by air cooling at a rate of 25°C / s, resulting in a wire with an aluminum-silicon coating 3 on its surface. The wire diameter of the wire substrate 1 is 14mm, and the thickness of the aluminum-silicon coating 3 is approximately 27μm. The microstructure is a ternary alloy τ5 phase with an α-Al+Fe-Al-Si layer on the surface (e.g., ...). Figure 3a (As shown).

[0064] The modified 14mm aluminized silicon wire was subjected to medium-frequency induction heating (frequency 8KHz, heated to 930℃, holding time approximately 35min); then a spring coiling process (hot coiling) was performed. After completion, the spring 100 was quenched in quenching oil at a cooling rate of over 45℃ / s to obtain a spring 100 with a martensitic structure; next, the spring 100 was tempered (heating temperature 435℃, holding time approximately 60min); then shot peening was performed using 0.6mm diameter shot with a strength of 0.45Amm to enhance the compressive stress on the surface; finally, electrophoretic powder coating was performed to obtain a spring 100 with an aluminized silicon coating 3, the thickness of which is approximately 36μm, and the microstructure is: α-Fe, Fe-Al binary alloy phase, Fe-Al-Si ternary alloy τ5 phase, Fe-Al binary alloy phase (e.g., ... Figure 3b As shown in Table 1, see Implementation 1.

[0065] Example 2,

[0066] 16mm diameter 54SiCr6 wire rod was shot-peened (to a strength of approximately 0.2Amm-0.3Amm) to remove surface oil and oxide scale. Subsequently, it was drawn to obtain a 14mm diameter wire substrate 1. The surface drawing powder was then cleaned with a brush, followed by high-frequency induction heating (100kHz, 630℃, 12m / min) while supersaturated water vapor was introduced at a flow rate of 12L / min. This process formed a dense protective film on the surface and increased its roughness. The wire is hot-dip plated in a plating bath (10 seconds, bath temperature 650℃, plating bath composition: Al: 89%, Si: 9%, remainder Fe), followed by air cooling at a rate of 25℃ / s, resulting in a wire with an aluminum-silicon coating 3 on the surface. The wire diameter of the base wire 1 is 14mm, and the thickness of the aluminum-silicon coating 3 is approximately 27μm. The microstructure is a ternary alloy τ5 phase with an α-Al+Fe-Al-Si layer on the surface (e.g., ...). Figure 3a (As shown).

[0067] The modified 14mm aluminized silicon wire was subjected to medium-frequency induction heating (frequency 8KHz, heating to 930℃, holding time approximately 35min), followed by quenching in quenching oil with a cooling rate of 45℃ or higher. Next, the wire was tempered (heating temperature 435℃, holding time approximately 60min) to obtain aluminized silicon oil-quenched and tempered steel wire with a martensitic structure. Then, a spring coiling process (cold coiling) was performed, and the coiled spring 100 underwent stress-relief annealing (annealing temperature approximately 180℃, holding time approximately 2H). Next, shot peening was performed using 0.6mm diameter shot with a strength of 0.45Amm to enhance surface compressive stress. Finally, electrophoretic powder coating was performed to obtain a spring 100 with an aluminized silicon coating 3, approximately 36μm thick, with a microstructure of: α-Fe, Fe-Al binary alloy phase, Fe-Al-Si ternary alloy τ5 phase, and Fe-Al binary alloy phase (e.g., ...). Figure 3b As shown in Table 1, see Implementation 2.

[0068]

[0069] Table 1. Components and coatings of the examples and comparative examples.

[0070] As a comparison case, the sample surface before molding had no coating (e.g. Figure 4a As shown), the surface of the formed wire substrate has a 5μm-6μm semi-decarburized layer due to heating (as shown). Figure 4b As shown in the figure, this results in a decrease in surface hardness of approximately 20 HRC, which reduces the surface strength.

[0071] Meanwhile, a comparison with GB / T10125-2012 (Artificial Atmosphere Corrosion Test - Salt Spray Test) revealed that springs with aluminum-silicon coatings exhibited a unilateral corrosion spread width of 0 mm after 480 hours of salt spray corrosion testing and approximately 0.5 mm after 720 hours; while springs without coatings showed a unilateral corrosion spread width of 1.2 mm after 480 hours and approximately 2.5 mm after 720 hours. The corrosion resistance of springs with aluminum-silicon coatings was significantly improved (see Table 2).

[0072]

[0073] Table 2. Composition and coating properties of the examples and comparative examples.

[0074] A vehicle according to a third aspect embodiment of the present invention includes a spring according to the first aspect embodiment described above.

[0075] According to embodiments of the present invention, by providing the springs described in the first aspect embodiment, the overall performance of the vehicle is improved and the service life of the vehicle is extended.

[0076] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0077] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0078] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0079] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0080] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A spring, characterized in that, include: The wire substrate has a circular cross-section; An oxide layer, the oxide layer covering the surface of the wire substrate; An aluminum-silicon coating is applied to the outer surface of the oxide layer. The mass percentage of each component in the aluminum-silicon coating is: Al: 80%-92%, Si≥8%, and the remainder is Fe. An electrophoretic layer is formed on the outer surface of the aluminum-silicon coating. The thickness of the aluminum-silicon coating is in the range of 30μm-45μm. The microstructure of the aluminum-silicon coating is: α-Fe, Fe-Al binary alloy phase, Fe-Al-Si ternary alloy τ5 phase, and Fe-Al binary alloy phase. The mass percentage of each component in the wire matrix is: C: 0.51%-0.63%, Si: 1.20%-1.60%, Mn: 0.35%-0.80%, P≤0.030%, S≤0.030%, Cr: 0.40%-0.80%, with the remainder being Fe. The diameter of the wire matrix is ​​in the range of 10mm-25mm.

2. A processing technology for a spring, characterized in that, For manufacturing the spring of claim 1, the processing technology includes: Step S1: Based on the design requirements and CAE analysis results, determine the wire diameter, strength, material grade, and shape of the spring; Step S2: Select a suitable wire diameter raw material and modify the wire diameter of the raw material; Step S3: Coil the modified wire into a spring; The modification of the wire diameter of the raw material in step S2 includes at least the following: sequential induction heating, pre-oxidation, and hot-dip aluminum-silicon plating of the raw material.

3. The processing technology of the spring according to claim 2, characterized in that, The temperature of the first induction heating wire is in the range of 550℃-650℃, and the time of the first induction heating wire is in the range of 20min-40min. At the same time as the first induction heating, saturated water vapor is sprayed on the surface of the wire substrate to form a dense oxide layer on the surface of the wire substrate.

4. The processing technology of the spring according to claim 3, characterized in that, The temperature of the hot-dip aluminum-silicon plating is in the range of 635℃-685℃, the time of the hot-dip aluminum-silicon plating is in the range of 5s-15s, and the hot-dip aluminum-silicon plating includes: hot-dip plating and air cooling performed sequentially, wherein the air cooling rate is in the range of 10℃ / s-30℃ / s.

5. The processing technology of the spring according to claim 3, characterized in that, Before the first induction heating, the raw materials are sequentially straightened, shot peened, drawn and cleaned. After the hot-dip aluminized silicon coating, the raw materials are sequentially inspected for flaws and marked with color marks.

6. The processing technology of the spring according to any one of claims 2-5, characterized in that, Step S3 includes: sequentially performing second induction heating, quenching, tempering, coiling, annealing, shot peening, and surface spraying on the wire substrate, wherein the second induction heating temperature of the wire substrate is in the range of 880℃-950℃, the quenching temperature is in the range of 880℃-950℃, the tempering temperature is in the range of 400℃-450℃, and the annealing temperature is in the range of 170℃-250℃.

7. The processing technology of the spring according to any one of claims 2-5, characterized in that, Step S3 includes: sequentially performing second induction heating, spring coiling, quenching, tempering, shot peening, and surface spraying on the wire substrate, wherein the second induction heating temperature of the wire substrate is in the range of 900℃-950℃, the temperature of the spring before quenching is not less than 850℃, and the tempering temperature is in the range of 400℃-450℃.

8. A vehicle, characterized in that, Includes the spring as described in claim 1.

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