Spring, processing technology of spring and vehicle

Abstract

The invention discloses a spring, a machining process of the spring and a vehicle. The spring comprises a wire rod base body, a wire rod and a spring, the surface of the wire base body is coated with the oxide layer; the aluminum-silicon coating is coated on the outer surface of the oxide layer, and the aluminum-silicon coating comprises the following components in percentage by mass: 80%-92% of Al, more than or equal to 8% of Si and the balance of Fe; and the electrophoresis layer is coated on the outer surface of the aluminum-silicon plating layer. According to the spring, the outer surface of the wire base body is coated with the compact oxide layer, the adhesive force of the coating is improved, the outer side of the oxide layer is coated with the aluminum-silicon coating, the anti-corrosion performance and the high-temperature-resistant performance of the spring are improved, the situations of oxide skin, decarburized layers and the like in the heating process are reduced, and the service life of the spring is prolonged. Therefore, the procedure of removing the oxide skin on the surface through shot blasting treatment is omitted, the working efficiency is improved, and meanwhile the environment-friendly effect is achieved.

Description

Technical Field

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

[0002] The relevant technology points out that with the development of lightweight automobiles, the strength requirements of coil springs as load-bearing safety parts are constantly increasing, and the risk of fracture is increasing. Therefore, it is particularly important to control the surface defects and corrosion failure of materials. In the prior art, some automobile coil springs are made of raw materials with uncoated thick wire diameters provided by steel mills, which are drawn into suitable spring wire diameters, and then the surface is cleaned, steam oxidized, and a series of processes are performed to obtain spring wire diameter wires, followed by a spring coiling process, which can be cold coiling or hot coiling.

[0003] Regardless of which solution is adopted, the automobile springs currently manufactured are all made of uncoated wire. During the hot coiling and quenching process, high temperature heating will cause surface oxidation, increase of oxide scale, decarburization of the surface, and reduce the strength and fatigue performance of the surface. The increase of oxide scale on the surface caused by hot coiling is particularly obvious, and a shot peening process is required to remove the oxide scale.

[0004] With the increase in the number of cars exported overseas and the complex use environment, more requirements are put forward for anti-corrosion performance. In the above scheme, the anti-corrosion performance is guaranteed by electrophoretic spraying after the finished product is made, because the main material of the spring is non-plated, which is easy to fail due to corrosion in harsh environments, especially in complex overseas use conditions. In addition, the temperature of the spring matrix during heating is as high as 900-1000℃, and the surface will oxidize during heating, resulting in an increase in oxide scale, increasing the number of cleaning times and reducing production efficiency; the wire is oxidized during high-temperature heating, resulting in surface decarburization, reduced surface hardness, and reduced fatigue life. Summary of the invention

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

[0006] The invention also provides a spring processing technology.

[0007] The present invention also provides a vehicle.

[0008] According to the first aspect of the present invention, the spring includes: a wire substrate, the cross-section of the wire substrate is formed into a circle; an oxide layer, the oxide layer is coated on the surface of the wire substrate; an aluminum silicon coating, the aluminum silicon coating is coated on 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 rest is Fe; an electrophoretic layer, the electrophoretic layer is coated on the outer surface of the aluminum silicon coating.

[0009] According to the spring of the present invention, a dense oxide layer is coated on the outer surface of the wire substrate to improve the adhesion of the coating, and an aluminum silicon coating is coated on the outer side of the oxide layer to improve the corrosion resistance and high temperature resistance of the spring, reduce the occurrence of oxide scale and decarburization layer during the heating process, thereby reducing the need for shot peening to remove the oxide scale on the surface, improve work efficiency and have 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 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%.

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

[0013] The processing technology of the spring according to the second aspect of the present invention is used to produce the spring according to the first aspect of the present invention, and the processing technology comprises:

[0014] Step S1, determining the wire diameter, strength, material grade and shape of the spring according to design requirements and CAE analysis results;

[0015] Step S2, selecting raw materials with suitable wire diameters, and modifying the wire diameters of the raw materials;

[0016] Step S3, coiling the reformed wire into a spring;

[0017] Wherein, the modification of the wire diameter of the raw material in step S2 at least includes: first induction heating, pre-oxidation and hot-dip aluminum silicon on the raw material in sequence.

[0018] According to the processing technology of the spring of the present invention, steam surface oxidation is carried out during the modification of the wire matrix to form a dense oxide layer, which has an isolation effect and improves the adhesion of the anti-corrosion and coating. In addition, during the modification of the raw materials, the surface of the wire matrix is ​​hot-dip coated with aluminum silicon. The heat resistance and corrosion resistance of the aluminum silicon coating can ensure that the decarburization of the spring and the shedding of the oxide scale are reduced during the subsequent heating process. At the same time, the aluminum silicon coating can greatly improve the anti-corrosion performance of the spring.

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

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

[0021] Furthermore, the hot-dip aluminum silicon includes: hot-dip and air-cooling performed in sequence, wherein the air-cooling speed is in the range of 10°C / s-30°C / s.

[0022] Furthermore, before the first induction heating, the raw materials are sequentially straightened, shot peened, drawn and cleaned, and after the hot-dip aluminum silicon coating, the raw materials are sequentially flaw-detected and color-coded.

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

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

[0025] A vehicle according to a third aspect of the present invention comprises the spring according to the first aspect of the present invention.

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

[0027] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

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

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

[0032] Figure 4a This is a metallographic photograph of the wire without aluminum silicon coating before heating;

[0033] Figure 4b This is a metallographic photograph of the wire without aluminum silicon coating after heating;

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

[0035] Reference numerals:

[0036] 100. Spring; 1. Wire substrate; 2. Oxide layer; 3. Aluminum silicon coating; 4. Electrophoretic layer. DETAILED DESCRIPTION

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

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

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

[0040] Specifically, the cross section of the wire substrate 1 is formed into a circle, the oxide layer 2 is coated on the surface of the wire substrate 1, and the roughness of the surface of the wire substrate 1 is increased. The aluminum silicon coating 3 is coated on the outer surface of the oxide layer 2. The aluminum silicon coating 3 has heat resistance and will not fall off during heating. The mass percentage of each component in the aluminum silicon coating 3 is: Al: 80%-92%, Si ≥ 8%, and the rest is Fe. The electrophoretic layer 4 is coated on the outer surface of the aluminum silicon coating 3. Therefore, the content of each component of the aluminum silicon coating 3 is different from that of the prior art, and the aluminum silicon coating 3 forms two metallographic structures of α-Al+Fe-Al-Si layer ternary alloy τ5 phase before hot forming, and the aluminum silicon coating 3 forms four metallographic structures of α-Fe, Fe-Al layer binary alloy phase, Fe-Al-Si layer ternary alloy τ5 phase, and Fe-Al layer binary alloy phase after heat treatment.

[0041] According to the spring 100 of the embodiment of the present invention, by coating the dense oxide layer 2 on the outer surface of the wire substrate 1, the adhesion of the coating is improved, and the aluminum silicon coating 3 is coated on the outer side of the oxide layer 2, the anti-corrosion performance and high temperature resistance of the spring 100 are improved, and the occurrence of oxide scale and decarburization layer during the heating process is reduced, thereby reducing the process of removing the oxide scale on the surface by shot peening, improving work efficiency and having an environmental protection effect. Moreover, the aluminum silicon coating 3 after heat treatment diffuses mutually, the thickness of the aluminum silicon coating 3 increases, the thickness of the aluminum silicon coating 3 is within the range of 30μm-45μm and has a four-layer structure (α-Fe, Fe-Al layer binary alloy phase, Fe-Al-Si layer ternary alloy τ5 phase, Fe-Al layer binary alloy phase four-layer metallographic structure), and the Fe-Al-Si layer ternary alloy τ5 phase alloy layer has excellent corrosion resistance, which improves the corrosion resistance of the spring 100. At the same time, the wire substrate 1 is protected from oxide scale and decarburization during the heating process, which improves work efficiency.

[0042] In some embodiments of the present invention, the mass percentages of the components in the wire matrix 1 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%.

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

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

[0045] Specifically, the processing technology includes:

[0046] Step S1, determining the wire diameter, strength, material grade and shape of the spring according to design requirements and CAE analysis results;

[0047] Step S2, selecting a suitable wire matrix and modifying the wire matrix;

[0048] Step S3, coiling the reformed wire substrate into a spring;

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

[0050] According to the processing technology of the spring 100 of the embodiment of the present invention, water vapor surface oxidation is performed during the modification of the wire substrate 1 to form a dense oxide layer 2, which has an isolation effect and improves the adhesion of the anti-corrosion and coating. In addition, during the modification of the raw materials, the surface of the wire substrate 1 is hot-dip coated with aluminum silicon. The heat and corrosion resistance of the aluminum silicon coating 3 can ensure that the decarburization of the spring 100 and the shedding of the oxide scale are reduced during the subsequent heating process. At the same time, the aluminum silicon coating 3 can greatly improve the anti-corrosion performance of the spring 100.

[0051] Further, the temperature of the first induction heating wire is in the range of 550°C-650°C, 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 may be: 550°C, 560°C, 570°C, 580°C, 590°C, 600°C, 610°C, 620°C, 630°C, 640°C, 650°C, etc.; the time of the first induction heating may 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] Further, the temperature of the hot-dip aluminum silicon is in the range of 635°C-685°C, and the time of the hot-dip aluminum silicon is in the range of 5s-15s. For example, the temperature of the hot-dip aluminum silicon can be 635°C, 640°C, 645°C, 650°C, 655°C, 660°C, 665°C, 670°C, 675°C, 680°C, 685°C, etc.; the time of the hot-dip aluminum silicon 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 includes: hot-dip and air-cooling performed sequentially, wherein the air-cooling speed is in the range of 10°C / s-30°C / s. For example, the air-cooling speed may be 10°C / s, 15°C / s, 20°C / s, 25°C / s, 30°C / s, and the like.

[0055] Furthermore, the wire substrate 1 is sequentially straightened, shot peened, drawn and cleaned before the first induction heating, and the wire substrate 1 is sequentially flaw-detected and color-coded after hot-dip aluminum silicon. The process of the reform in step S2 is: raw material → straightening → shot peening → drawing and reforming → cleaning → first induction heating (steam surface oxidation) → hot-dip aluminum silicon → flaw-detection → color coding.

[0056] Specifically, the temperature of the first induction heating is 550-650°C, and the time is controlled at about 30 minutes according to the speed of wire release. At the same time, saturated water vapor is sprayed on the surface of the wire substrate 1 to form a dense Fe3O4 oxide layer 2 on the surface of the wire substrate 1. The oxide layer 2 can increase the surface roughness and improve the adhesion in the subsequent aluminum silicon plating process. At the same time, the dense oxide layer 2 has a good isolation and barrier effect, which can improve the corrosion resistance of the wire. The temperature of the plating tank during the hot-dip aluminum silicon process is 635-685°C, and the coating composition is Al: 80%-92%, Si ≥ 8%, and the rest is Fe. The time passing through the plating tank is 5S-15S, and then it is cooled by air cooling at a rate of 10℃ / S-30℃ / S to obtain a wire substrate 1 with an aluminum silicon coating 3 (coating structure α-Al+Fe-Al-Si layer ternary alloy τ5 phase, thickness of about 20-30μm), followed by flaw detection and color coding (such as Figure 1 and Figure 3a shown);

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

[0058] Specifically, the process of coiling the spring is: second induction heating → quenching → tempering → coiling the spring → annealing → shot peening → surface spraying. The wire substrate 1 is subjected to second induction heating before quenching, and the second induction heating temperature is between 880°C and 950°C. The quenching temperature is between 880°C and 950°C, that is, the wire substrate 1 is subjected to second induction heating to the temperature required for quenching before quenching. Oil quenching or water quenching can be used. The tempering temperature is set between 400°C and 450°C. The wire substrate 1 obtains a tempered troostite structure. During the quenching and tempering process, the basic mechanical properties of the wire substrate 1 are improved. At the same time, the aluminum silicon coating 3 on the surface will undergo an alloying process, and the thickness of the aluminum silicon coating 3 becomes thicker. The thickness of the aluminum silicon coating 3 is between 30μm and 45μm. The annealing temperature is 170°C to 250°C, which eliminates the stress in the coiling process. Shot peening enhances the compressive stress on the surface of the spring 100. That is, the coiling process of the spring 100 is cold coiling, and the coiling of the spring 100 is completed at room temperature.

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

[0060] Specifically, the process of coiling the spring is: second induction heating → coiling → quenching → tempering → shot peening → surface spraying. The wire substrate 1 is heated to a range of 900°C-950°C, and the aluminum silicon coating 3 on the surface will undergo an alloying process, and the thickness of the aluminum silicon coating 3 becomes thicker. The thickness of the aluminum silicon coating 3 is between 30μm-45μm, and then the coiling process is performed. After coiling the spring, the residual heat is used to perform quenching treatment immediately, and the temperature of the spring 100 before entering the quenching tank is controlled to be ≥850°C. The tempering temperature is set between 400°C-450°C, and then the surface is sprayed. Compared with the traditional process, there is no need to perform a descaling process after quenching and tempering. That is, the coiling process of the spring 100 is hot coiling, and the coiling of the spring 100 is completed when the temperature is greater than 850°C.

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

[0062] Embodiment 1,

[0063] A 54SiCr6 wire rod with a wire diameter of 16 mm was used, and after shot peening (strength of about 0.2Amm-0.3Amm) to remove oil and oxide scale on the surface, the wire diameter was then drawn to obtain a wire matrix 1 with a wire diameter of 14 mm. The wire drawing powder on the surface was then cleaned with a brush, followed by high-frequency induction heating (frequency of 100KHz, heating temperature of 630°C, heating time of about 20 minutes); at the same time, supersaturated water vapor was introduced, and the flow rate of water vapor was 12L / min, forming a dense oxide layer 2 on the surface, while increasing the surface roughness. The wire substrate 1 passes through a plating bath (time is 10S, the temperature of the plating bath is 650°C, the composition of the plating bath is Al: 89%, Si: 9%, and the rest is Fe, hot dip plating, and then air cooling at a cooling rate of 25°C / S, thereby obtaining a wire having an aluminum silicon coating 3 on the surface. The wire diameter of the wire substrate 1 is 14mm, the thickness of the aluminum silicon coating 3 is about 27μm, and the organizational structure is that the surface layer is a ternary alloy τ5 phase of α-Al+Fe-Al-Si layer, (such as Figure 3a shown).

[0064] The modified 14mm aluminum-silicon coated wire is subjected to medium frequency induction heating (frequency is 8KHz, heating to 930℃, and holding time is about 35min); then the spring coiling process (hot coiling) is carried out, and after completion, the spring 100 is placed in quenching oil for quenching, and the cooling rate is above 45℃ / S to obtain a spring 100 with a martensitic structure; then the spring 100 is tempered (heating temperature 435℃, holding time is about 60min); then shot peening is performed using pellets with a diameter of 0.6mm and a strength of 0.45Amm to enhance the surface compressive stress, and finally electrophoresis spraying is performed to obtain a spring 100 with an aluminum-silicon coating 3, the thickness of the aluminum-silicon coating 3 is about 36μm, and the organizational structure is: α-Fe, Fe-Al layer binary alloy phase, Fe-Al-Si layer ternary alloy τ5 phase, Fe-Al layer binary alloy phase (such as Figure 3b As shown in Table 1, see Implementation 1.

[0065] Embodiment 2:

[0066] A 54SiCr6 wire rod with a wire diameter of 16 mm was used, and after shot peening (strength of about 0.2Amm-0.3Amm) to remove oil and oxide scale on the surface, the wire diameter was then drawn to obtain a wire matrix 1 with a wire diameter of 14 mm. The wire drawing powder on the surface was then cleaned with a brush, and then high-frequency induction heating (frequency of 100KHz, heating temperature of 630°C, heating time of 12m / min) was performed, and supersaturated water vapor was introduced at a flow rate of 12L / min, forming a dense protective film on the surface and increasing the surface roughness. The wire rod passes through a plating bath (time is 10S, the temperature of the plating bath is 650℃, the composition of the plating bath is Al: 89%, Si: 9%, and the rest is Fe), hot dip plating, and then air cooling at a cooling rate of 25℃ / S, thereby obtaining a wire rod with an aluminum silicon coating 3 on the surface, the wire diameter of the wire rod substrate 1 is 14mm, the thickness of the aluminum silicon coating 3 is about 27μm, and the organizational structure is a surface layer of α-Al+Fe-Al-Si layer ternary alloy τ5 phase, (such as Figure 3a shown).

[0067] The reformed 14mm aluminum-silicon coated wire is subjected to medium frequency induction heating (frequency is 8KHz, heated to 930℃, and the holding time is about 35min), and then quenched in quenching oil with a cooling rate of 45℃ / or above; then the wire is tempered (heating temperature is 435℃, and the holding time is about 60min) to obtain aluminum-silicon oil quenched and tempered steel wire with martensitic structure; then the spring coiling process (cold coiling) is carried out, and the coiled spring 100 is subjected to stress relief annealing (annealing temperature is about 180℃, and the holding time is about 2H), and then shot peening is carried out with pellets with a diameter of 0.6mm and a strength of 0.45Amm to enhance the surface compressive stress, and finally electrophoresis spraying is carried out to obtain a spring 100 with an aluminum-silicon coating 3, the thickness of the aluminum-silicon coating 3 is about 36μm, and the organizational structure is: α-Fe, Fe-Al layer binary alloy phase, Fe-Al-Si layer ternary alloy τ5 phase, Fe-Al layer binary alloy phase (such as Figure 3b As shown), see Table 1 Implementation 2.

[0068]

[0069] Table 1 Composition and coating of examples and comparative examples

[0070] As a comparative case, the surface of the sample before molding had no coating (such as Figure 4a As shown in the figure, the surface of the wire matrix after forming has a 5μm-6μm semi-decarburized layer on the surface due to heating (as shown in the figure Figure 4b As shown), the surface hardness is reduced by about 20HRC, which reduces the strength of the surface;

[0071] At the same time, according to GB / T10125-2012 (artificial atmosphere corrosion test salt spray test), it was found that the spring with aluminum silicon coating had a single-sided corrosion width of 0 at 480 hours in the salt spray corrosion test, and a single-sided corrosion width of about 0.5mm at 720 hours; while the spring without coating had a single-sided corrosion width of 1.2mm at 480 hours, and a single-sided corrosion width of about 2.5mm at 720 hours; the corrosion resistance of the spring with aluminum silicon coating was significantly improved (see Table 2).

[0072]

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

[0074] A vehicle according to an embodiment of a third aspect of the present invention comprises a spring according to an embodiment of the first aspect of the present invention.

[0075] The vehicle according to the embodiment of the present invention is provided with the spring of the first embodiment, thereby improving the overall performance of the vehicle and extending the service life of the vehicle.

[0076] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0077] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0078] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0079] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

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

Claims

1. A spring, characterized in that: include: A wire substrate, wherein the cross section of the wire substrate is formed into a circle; An oxide layer, the oxide layer being coated on the surface of the wire substrate; An aluminum-silicon coating, the aluminum-silicon coating is coated on the outer surface of the oxide layer, and the mass percentage of each component in the aluminum-silicon coating is: Al: 80%-92%, Si ≥ 8%, and the rest is Fe; An electrophoretic layer is coated on the outer surface of the aluminum silicon coating.

2. The spring according to claim 1, characterized in that The thickness of the aluminum silicon coating is in the range of 30 μm-45 μm, and the organizational structure 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.

3. The spring according to claim 1, characterized in that 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%, and the diameter of the wire matrix is ​​in the range of 10mm-25mm.

4. A spring processing technology, characterized in that: For producing a spring according to any one of claims 1 to 3, the processing technology comprises: Step S1, determining the wire diameter, strength, material grade and shape of the spring according to design requirements and CAE analysis results; Step S2, selecting raw materials with suitable wire diameters, and modifying the wire diameters of the raw materials; Step S3, coiling the reformed wire into a spring; Wherein, the modification of the wire diameter of the raw material in step S2 at least includes: first induction heating, pre-oxidation and hot-dip aluminum silicon on the raw material in sequence.

5. The spring processing technology according to claim 4, characterized in that: The temperature of the first induction heating wire is in the range of 550°C-650°C, the time of the first induction heating wire is in the range of 20min-40min, and saturated water vapor is sprayed on the surface of the wire substrate during the first induction heating to form a dense oxide layer on the surface of the wire substrate.

6. The spring processing technology according to claim 5, characterized in that: The temperature of the hot-dip aluminum silicon is in the range of 635°C-685°C, the time of the hot-dip aluminum silicon is in the range of 5s-15s, and the hot-dip aluminum silicon includes: hot-dip and air-cooling performed in sequence, wherein the air-cooling speed is in the range of 10°C / s-30°C / s.

7. The spring processing technology according to claim 5, characterized in that: Before the first induction heating, the raw materials are sequentially straightened, shot peened, drawn and cleaned, and after the hot-dip aluminum silicon coating, the raw materials are sequentially flaw-detected and color-coded.

8. The spring processing technology according to any one of claims 4 to 7, characterized in that: The step S3 comprises: 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°C-950°C, the quenching temperature is in the range of 880°C-950°C, the tempering temperature is in the range of 400°C-450°C, and the annealing temperature is in the range of 170°C-250°C.

9. The spring processing technology according to any one of claims 4 to 7, characterized in that: The step S3 comprises: 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°C-950°C, the temperature of the spring before quenching is not less than 850°C, and the tempering temperature is in the range of 400°C-450°C.

10. A vehicle, characterized in that: The invention comprises the spring according to any one of claims 1 to 3.

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