WO2005107974A1 - A casting and forging process of aluminum wheel which include spokes comprise: producing a wheel spoke member by low pressure cast, heating the member to the temperature of plastic deformation, then putting the member into a forging die for high pressure cast. the process further comprise: detecting the wheel spoke member f - Google Patents

Abstract

A casting and forging process of aluminum wheel which include spokes comprise: producing a wheel spoke member by low pressure cast, heating the member to the temperature of plastic deformation, then putting the member into a forging die for high pressure cast. The process further comprise: detecting the wheel spoke member for defect, machining the member to the desired dimension by machine work, then assembling the spoke member and a responding wheel rim for a completed wheel. The invention reduces the production steps, shortens the producing time, increases the availability of mental material, cuts off 40 % cost of the final product. The further advantage is that the completed wheel has 10 % elongation and more than 250N/mm tensile strength in the central hole section.

Description

 Technical field of casting and forging of aluminum wheels

 The present invention relates to the technical field of manufacturing aluminum alloy wheels for automobiles and other types of motor vehicles, and particularly to a casting and forging process for replacing traditional "forging slab forging" aluminum wheels with "forging slab forging".

 Background technique

 The manufacturing of automotive aluminum wheels generally includes casting, forging, spinning rims, (plate) spinning and rolling technologies.

 The traditional casting process of aluminum wheels includes gravity casting and squeeze casting. The former is usually a method of using gravity (without any additional pressure) to make the molten metal flow and fill the cavity. This casting method is widely used due to its advantages such as lower production cost, greater freedom of appearance and modeling, lighter weight than cast slabs, and reliable strength. But because this process only uses gravity to fill the cavity with aluminum liquid, compared with other pressure casting and forging methods, the density of the billet formed after the injection of aluminum liquid into the mold is lower; at the same time, the large wall thickness required to meet the strength of the wheel , Increased the weight of aluminum wheels.

 In order to meet the requirements of high strength and low weight of aluminum wheels, compared with the aforementioned gravity casting, extrusion casting uses high pressure to quickly fill the cavity with aluminum liquid to obtain higher density products. The production cost of extrusion casting of aluminum wheels is higher than the cost of gravity casting. The reason is that its performance depends on the pressure (that is, the higher the pressure, the higher the cost of the machine). It is usually sold in OEM and afterniarket. Aluminium wheels are generally "pressure field" cast products.

 In addition to gravity casting and squeeze casting, there are spinning rims, (plate) spinning and rolling technologies. The forming process of aluminum wheels manufactured by this method is: firstly casting the slab with low pressure, spinning the slab with a special machine tool, then heating the outside of the slab, and then rolling the rim into the final width and shape by hot rolling. . The rim portion thus obtained has the same strength as the forged wheel without the need for higher costs.

Finally, the forging technology is introduced. This method uses solid pressure to form a solid aluminum billet in the forging die cavity. The final billet is undoubtedly very dense and strong, so the product can also be very light. Forging methods of traditional aluminum wheels need to go through the following steps: (1) smelting, (2) casting into round billets, (3) homogenizing materials, (4) extruding billets, (5) cutting, (6) heating, (7) Forging billets, (8) heating, (9) preliminary forging, (ίθ) heating, (11) precision forging, (12) removing flash, (13) heat treatment, (14) fluorescent inspection, (15) Machining. Through these fifteen steps, it is clear that the traditional forging method is time-consuming and material-intensive. Compared with the above-mentioned casting and rolling methods, the forging processing costs and equipment development have greatly restricted the promotion of the aluminum wheel forging process, resulting in very rare forged aluminum wheels on the market and the price is very expensive. With the increasingly high performance requirements of aluminum wheels in the market today, existing cast and rolled aluminum wheels cannot fully meet the high performance requirements.

 Summary of the invention

 The purpose of the present invention is to solve the deficiencies in the prior art mentioned above, and provide a casting and forging process for aluminum wheels. Compared with the traditional forging method, the process is simple to operate, the overall cost is significantly reduced, and the product performance of aluminum wheels is comparable to or even higher than that of the forging wheel. At the same time, the process is easy to repeat production and easy to promote.

 The purpose of the present invention is achieved by the following technical solution: The casting and forging process of an aluminum wheel includes the casting and forging process of a wheel spoke, and includes the following steps: First, a low pressure casting or gravity casting spoke is produced, and the spoke is heated to the plastic deformation temperature of the material Then, put the heated spokes into a forging die for high-pressure forging, then check whether the forged spokes are defective, and then machine the forged spokes into semi-finished spokes. Finally, combine it with the corresponding rim to form a complete wheel.

The high pressure forging is to compress a heated spoke casting by about 5 to 20 mm; the pressure of the low pressure casting is about 0.1 to 1 kg / cm ² , and the pressure of the high pressure forging is about 500 to 1000 kg / cm ² ; the forged spokes Defect detection uses fluorescent flaw detection, or other known flaw detection techniques; the machined spokes refer to processing the spokes to the required spoke size, and also include the dimensions of the processing and assembly accessories, such as center holes, valve holes, etc .; The machined spokes and the rim are connected by bolts or welded into a wheel; the spoke material is mainly composed of aluminum, and generally includes the following constituent elements: In terms of mass percentage, Si is about 6 ~ 8%, Mg is about 0.25 ~ 0.45%, Ti about 0.1 ~ 0.2%, Sr about 0.01 ~ 0.02%, Fe about 0.1 ~ 0.2%, the rest is A1; it can also be about 6 ~ 8% Si, Mg about 0.25-0.45%, Ti about 0.1 ~ 0.2%, Sr about 0.01 ~ 0.02%, Fe about 0.:! ~ 0.2%, L is about 0.2%, C is about 0.2%, and the rest is Al, which uses L-type and C-type additives provided by Guangzhou Huatai Aluminum Wheel Co., Ltd. ,

 Compared with the prior art, the present invention has obvious advantages and beneficial effects. For example, compared with the traditional forging process, the required production steps are: (1) smelting, (2) casting into a round billet, (3) material Homogenization, (4) extruded billet, (5) cut, (6) heating, (7) forging billet, (8) heating,

(9) preliminary forging, (10) heating, (11) precision forging, (12) removing flash, (13) heat treatment, (14) fluorescent inspection, (15) machining forming. The present invention reduces the number of production steps compared to the above method, so Significantly reduced processing time, increased use of metallic materials, reduced overall manufacturing processes and reduced final product costs by almost 40%. Since the present invention uses a cast slab as a forged billet, it provides an unlimited free design for the spokes. Because of the use of Al-Si-Mg alloy materials in the present invention combined with the casting and forging process described above, the wheels produced are rarely defective, such as pinholes, and the aluminum wheels manufactured at the same time even in the center hole region can reach 10% elongation and have higher than 250N / mm ² tensile strength, the most attractive is preserved a large degree of freedom in modeling casting wheel great advantage of the method. This ensures that a variety of high-end aluminum wheels can be provided for today's automotive industry.

 BRIEF DESCRIPTION OF THE DRAWINGS

 The drawings herein are an integral part of the description of the present invention and provide further understanding of the present invention. First, the main body of the invention is represented by figures, and the corresponding detailed explanation is used to explain the principle of the invention. as the picture shows:

 Figure 1 is a flowchart of the corresponding process of the traditional forging method;

 2 is a schematic diagram of each manufacturing process of the casting and forging process of the present invention;

 A to e in FIG. 3 are schematic diagrams of each step of connecting a spoke to a spinning rim in the present invention; and FIGS. 3 to c are sectional views of an assembly connecting the spoke and the rim by bolts;

 FIG. 4 is a schematic diagram of each manufacturing process of the casting and forging manufacturing method of the present invention, including a process from a casting slab to a forging slab.

 detailed description

 The corresponding characteristics of each part of the figure are explained from different angles below. Figures 2 to 4 are schematic illustrations of the different manufacturing steps and their charts of the casting and forging method of the present invention.

 Figure 1 is a traditional aluminum wheel forging method, which specifically includes the following steps: (1) 10 smelting, (2) 12 casting into a round billet, (3) 14 material homogenization, (4) 16 extruded billet, (5 ) 18 cuts, (6) 20 heating, (7) 22 forging billets, (8) 24 heating, (9) 26 preliminary forging, (10) 28 heating, (11) 30 fine forging, (12) 32 removing fly Edge, (13) 3 "4 heat treatment, (14) 36 fluorescent flaw detection, (15) 38 machining.

 In summary, the present invention aims to simplify and combine the first 8 steps of the above-mentioned aluminum wheel manufacturing process (ie, from (1) to (8)), directly heating and forging with a cast slab, and then processing the forged wheel into The required dimensions of the product. It is proved through experiments that the aluminum wheels manufactured by the casting and forging process in the present invention and their mechanical properties are superior to the conventional cast or forged aluminum wheels.

As shown in the figure, the casting and forging process of the present invention first uses low pressure casting to produce a The spokes 40 of the rim 42. As shown in 43, low-pressure casting uses air pressure technology, and the air pressure ranges from about 0.1 to 1 kg / cm ² . As shown in FIG. 44, after the above-mentioned low-pressure casting process is completed, the spoke 40 is heated to its plastic temperature, and the temperature thereof is a commonly known plastic deformation temperature of the aluminum material. Once the plastic temperature is reached, the spokes 40 are put into a forging die 45, and the heated spokes are forged under high pressure into a finished shape. A screw press of about 8,000 tons is used for forging and casting the spokes 40 under high pressure. According to the structure and performance requirements of the wheel, the deformable compression amount after high pressure is 5-20 mm, as shown by the X mark in FIG. 4. Compared with the aforementioned pressure used for low-pressure casting, which is about 0.1 to 1 kg / cm ² , the screw press used for high-pressure castings produces a pressure of about 500 to 1000 kg / cm ² . After the spoke casting is solidified within a predetermined time interval, the forged spokes 46 can be ejected from the mold by the ejector mechanism of the forging press.

 Finally, the forged spokes 46 are inspected by fluoroscopy for defects in the interior, including inspection of the forged spokes using known X-rays. The inspection of the forged spokes can also be performed by other common detection techniques without departing from the scope of the present invention.

 If no internal defects are found in the forged spokes 46, the mechanical properties of the material can then be improved by heat treatment according to the properties of the material. The heat-treated spokes are then machined to the required size. This machining process also includes the dimensions required when processing and assembling accessories such as: center hole, valve hole and bead seat. At the same time, parameters such as offset and center diameter of bolt hole (PCD) should be considered to meet the requirements of automobiles and tires. Assembly requirements.

 To form a complete wheel, the rim 48 may be manufactured by a conventional spinning forming process, that is, an aluminum plate is spin-formed in a spinning mold, and the rim may be manufactured by other methods without departing from the scope of the present invention. For example: simply cut the aluminum pipe into a rim, or roll the aluminum plate first and then join it into a rim. Obviously, the objective of the present invention can still be achieved by using gravity casting instead of the low-pressure casting process.

 Referring to a ~ e in FIG. 3, after the rim 48 is spin-formed, the forged spokes 46 and the spun rim 48 can be connected by bolts 50 to ensure the balanced performance of the wheel assembly, such as well-known methods (see a ~ c). In addition, there are other mature processes to connect the forged spokes 46 and the spinning rims 48, such as welding the forged spokes 46 and the spinning rims 48 by welding to produce lightweight wheels. In addition to bolted connections, forged spokes and spun rims can also be connected by conventional sealants (such as 49 sealing adhesive) to prevent air leakage between the spokes and the rim after the tire is mounted. When the wheel 52 is assembled, the wheel can be inspected as shown in Fig. 3 (d), and then sent as shown in Fig. 3 (e).

In order to meet the performance requirements of forged wheels, the aluminum material used in the casting and forging process in the present invention is one A special chemical composition of materials to facilitate the casting process and produce wheels that meet the requirements of forging performance. This alloy material is composed of A1-Si-Mg and other elemental components. The elemental components can have the following solutions: (1) Si about 6%, Mg about 0.25%, Ti about 0.1%, Sr about 0.01%, Fe about 0.1 %, The rest is A1; (2) Si is about 8%, Mg is about 0.45%, Ti is about 0.2%, Sr is about 0.02%, Fe is about 0.2%, and the rest is A1; (3) Si is about 6.58%, Mg is about 0.3% , Ti is about 0.2%, Sr is about 0.18%, Fe is about 0.16%, L is about 0.2%, C is about 0.2%, and the rest is Al. In the present invention, a product produced by a material using such a component through a casting and forging method can meet or even surpass the requirements of the strength, weight, and performance of today's forged wheels.

 Through the above, different changes to the casting and forging process will not depart from the scope of the present invention. For example: When the forged spokes are described as including a partial rim or connected to a spinning rim, it is easy to think that the forged spokes can be produced with or without a partial rim and can be connected to a rim. In addition, it is easy to judge that the invention produces

This method is not limited to the manufacture of spokes, but can also be used to produce any other forgeable product. Although the details of the present invention have been specifically described herein with graphics, they are not limited to the details of the described invention. The implication is that any changes or modifications to the details of the invention will not depart from the spirit of the invention.

Claims

Claim 1. The casting and forging process of aluminum wheels, including the casting and forging process of wheel spokes, characterized in that the casting and forging process of wheel spokes includes the following steps:  Production of a spoke casting by low pressure casting or gravity casting;  Heating the spoke casting to its material plastic deformation temperature;  Placing the heated spoke casting into a forging die, and forging the spoke casting into a forged spoke under high pressure;  Detecting defects in the forged spokes; and  The forged spokes are machined.  2. The casting and forging process for an aluminum wheel according to claim 1, wherein the high-pressure forging compresses the heated spoke casting by about 5 to 20 mm. 3. The casting and forging process for aluminum wheels according to claim 1, wherein the pressure of the low-pressure casting is about 0.1 to 1 kg I cm ² , and the pressure of the high-pressure forging is about 500 to 1000 kg I cm ² .  4. The casting and forging process for an aluminum wheel according to claim 1, wherein the forged wheel spoke defect detection is performed by a fluoroscopy method.  5. The casting and forging process for an aluminum wheel according to claim 1, wherein the machined spokes include machining of dimensions for mounting attachments.  6. The casting and forging process for an aluminum wheel according to claim 1, further comprising assembling the machined spokes and rim assembly to form a wheel.  7. The casting and forging process for an aluminum wheel according to claim 6, wherein the machined spokes are connected to the rim by bolts or welding.  8. The casting and forging process for an aluminum wheel according to claim 1, wherein the spokes are processed from a material made of an aluminum alloy.  9. The casting and forging process for an aluminum wheel according to claim 8, characterized in that the aluminum alloy contains elemental components with the following mass ratios: Si is about 6 to 8%, Mg is about 0.25 to 0.45%, and Ti is about 0.1 to 0.2%, Sr about 0.01 ~ 0.02%, Fe ^ 0.1-0.2%, the rest is Al. 10. The casting and forging process for an aluminum wheel according to claim 8, wherein the aluminum alloy contains elemental components with the following mass ratios: about 6 to 8% Si, about 0.25 to 0.45% Mg, and about 0.1 to Ti 0.2%, Sr about 0.01 ~ 0.02%, Fe about 0.1 ~ 0.2%, L about 0.2%, C about 0.2%, the rest are AI o  The casting and forging process for an aluminum wheel according to claim 8, wherein the aluminum alloy package contains the following elemental components in mass ratios: Si is about 6.58%, Mg is about 0.3%, and Ti is about 0.2 ° /. Sr is about 0.18%, Fe is about 0.16%, L is about 0.2%, C is about 0.2%, and the rest is Al.  12. The casting and forging process of an aluminum wheel as claimed in claim 1, to form a spoke of a wheel.  13. The casting and forging process of aluminum wheels, including the casting and forging process of wheel spokes, is characterized in that the casting and forging process of wheel spokes includes the following steps:  Production of a spoke casting by low pressure casting or gravity casting;  Heating the spoke casting to its material plastic deformation temperature; and  The heated spoke casting was put into a forging die, and the spoke casting was forged under high pressure into a forged spoke.  14. The casting and forging process for an aluminum wheel according to claim 13, further comprising the following steps:  Detecting defects in the forged spokes; and  The forged spokes are machined.  15. The casting and forging process for aluminum wheels according to claim 13, wherein the high-pressure forging compresses the heated spoke castings by about 5 to 20 mm. 16. The process of claim 13 casting and forging of aluminum wheels, characterized in that the low pressure casting about 0.1~lkg / cm ^2, the high-pressure forging about 500~1000kg / 17. The casting and forging process for aluminum wheels according to claim 14, wherein the forged spoke defect detection is performed by a fluoroscopy method.  18. The casting and forging process for an aluminum wheel according to claim 14, further comprising assembling the machined spokes and rim assembly to form a wheel.  19. The casting and forging process for an aluminum wheel according to claim 18, wherein the machined spokes are connected to the rim by bolts or welding.  20. The casting and forging process for an aluminum wheel according to claim 12, wherein the spokes are processed from a material made of an aluminum alloy. 21. The casting and forging process for an aluminum wheel according to claim 20, wherein the aluminum alloy contains elemental components with the following mass ratios: about 6 to 8% Si, about 0.25 to 0.45% Mg, and about 0.1 to Ti 0.2%, Sr about 0.01 ~ 0.02%, Fe about 0.1 ~ 0.2%, and the rest is Al.  22. The casting and forging process for an aluminum wheel according to claim 20, wherein the aluminum alloy contains elemental components with the following mass ratios: Si is about 6 to 8%, Mg is about 0.25 to 0.45%, and Ti is about 0.1 to 0.2%, Sr about 0.01 ~ 0.02%, Fe about 0.1 ~ 0.2%, L about 0.2%, C about 0.2%, the rest is Ah  23. The casting and forging process for an aluminum wheel according to claim 20, wherein the aluminum alloy contains elemental components with the following mass ratios: approximately 6.58% Si, approximately 0.3% Mg, approximately 0.2% Ti, and approximately 0.18 Sr %, Fe is about 0.16%, L is about 0.2%, C is about 0.2%, and the rest is Al.