JPH0559501A - Manufacture of automobile wheel using aluminum alloy expanded steel - Google Patents

Abstract

PURPOSE:To reduce the thickness of a sheet by forming an Al alloy contg. specified amounts of Mg, Si, Cu, Cr, Fe, Mn, Zn and Ti, assembling a rim and a disk to be welded, thereafter executing heat treatment in specified conditions. CONSTITUTION:An aluminum alloy expanded sheet constituted of 0.8 to 1.2% Mg, 0.4 to 0.8% Si, 0.15 to 0.4% Cu, 0.04 to 0.35% Cr, <=0.7% Fe, <=0.15% Mn, <=0.25% Zn, <=0.15% Ti and the balance Al with inevitable impurities and recrystallized aluminum alloy expanded sheet by annealing is formed into a rim 1 and a disk 2 having required shapes. Both are assembled to be welded, are subjected to soln. annealing at 516 to 579 deg.C, thereafter subjected to age hardening treatment at a room temp. or 154 to 166 deg.C to manufacture an automobile wheel 4. By executing the heat treatment after the assembling, strains caused by thermal effect are reduced, more excellent strength can be obtd. and its sheet thickness is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an automobile wheel using a heat treated aluminum alloy wrought sheet material.

[0002]

2. Description of the Related Art Conventionally, aluminum alloy sheets, which are wrought materials used for automobile wheels, are concerned with workability and dimensional accuracy of products. Avoiding heat-treating type alloys, an aluminum alloy of the A5000 series, which has a relatively high elongation, good tensile strength, and good proof stress, and is of temper type O, is used.

[0003]

However, although an automobile wheel using a conventional wrought aluminum alloy plate is lighter than a wheel using a steel plate, in order to satisfy the strength of the wheel, a plate made of a material is used. Inevitably, the thickness of aluminum is 34% of the specific gravity of iron, but the wheel for automobiles using the above wrought aluminum material has about 80% of the steel plate.
In the present situation, the weight was only 20%, and the weight was only about 20%. Further, since the elongation is less than that of the steel sheet, there are problems that the degree of freedom in designing the disk is reduced, the formability is deteriorated, the number of processing steps is increased, and an extra die is required.

[0004]

The present invention has been made in order to eliminate the above-mentioned problems, and Mg: 0.8 to 1.2.
%, Si: 0.40 to 0.8%, Cu: 0.15 to 0.40%,
Cr: 0.04 to 0.35% as a main component, Fe: 0.7% or less, Mn: 0.15% or less, Zn: 0.25% or less, Ti:
An aluminum alloy wrought plate material containing 0.15% or less, the balance of which is Al and unavoidable impurities, and recrystallized by annealing is molded to form a rim and a disk having a required shape, and The rim and disk are assembled and welded, and then solution treatment is performed at 516 ° C to 579 ° C.
Then, by performing age hardening treatment at room temperature or at a temperature of 154 ° C to 166 ° C, a method for manufacturing an automobile wheel using an aluminum alloy wrought sheet material having high designability and excellent tensile strength and proof stress. is there.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the disc has Mg: 1.0%,
Si: 0.6%, Cu: 0.25%, Cr: 0.25% as main components, and Fe: 0.5%, Mn: 0.12%, Zn: 0.
20%, Ti: 0.13%, the balance consisting of Al and inevitable impurities, made from an aluminum alloy wrought sheet material recrystallized by annealing. Then, it is formed by punching, then finishing it into a desired disk shape by several drawing steps, punching out mounting bolt holes, decorative windows, and finishing steps such as bending and coining.

Further, as shown in FIG. 2, the rim is made of the same material as the disc, and is cut to a required length in the cutting process.
After the cut plate material is bent into a cylindrical shape in the bending step, both ends are butted and welded, the welded portion is trimmed or edge cut to form a cylindrical material, and the cylindrical material is flared and rolled. It is finished into the required rim shape in the process and formed into the final rim shape in the sizing process.

The disk 1 formed as described above is press-fitted into the rim 2 and the joint portion 3 between the disk 1 and the rim 2 is integrally joined by welding such as arc welding or spot welding. A wheel 4 as shown in FIG.

The wheel 4 is heated to 530 ° C. for solution treatment, and left at room temperature for 96 hours or more for age hardening treatment. The tensile strength is 32 to 34 Kgf / mm ² , and the proof stress is 2
An automobile wheel is formed having an elongation of 9% at 9 Kgf / mm ² .

In the above embodiment, the material is Mg: 0.8-
1.2%, Si: 0.40 to 0.8%, Cu: 0.15 to 0.40
%, Cr: 0.04 to 0.35% as a main component, and Fe: 0.7
% Or less, Mn: 0.15% or less, Zn: 0.25% or less, T
It is possible to use an aluminum alloy wrought sheet material containing i: 0.15% or less, the balance consisting of Al and unavoidable impurities, and recrystallized by annealing.

The solution treatment temperature is 516 ° C.
The temperature can be in the range of ˜579 ° C., and the age hardening treatment was performed at room temperature, but it can also be performed by heating at 154 ° C. to 166 ° C. for 5 hours to 20 hours.

[0011]

[Table 1]

As shown in Table 1, the elongation is large before the solution heat treatment and the tensile strength and the yield strength are small, so that the moldability is good, and after the solution heat treatment, the tensile strength and the yield strength are the same as those of the conventional ones. Excellent wheels were obtained in comparison.

[0013]

INDUSTRIAL APPLICABILITY As described above, the present invention uses a material having excellent elongation properties and good workability, and is subjected to a solution treatment after the molding process. It was possible to provide a vehicle wheel using a drawn sheet material. Also, by performing heat treatment after assembling, the disc and the rim have less distortion due to the heat effect, and it is possible to obtain more excellent strength. Therefore, it is possible to reduce the plate thickness of the disc and the rim. It is excellent in that it is possible to provide a vehicle wheel using an aluminum alloy wrought sheet material that can reduce the weight of the wrought material vehicle wheel, reduce the fuel consumption of the vehicle, and reduce the CO ₂ exhaust amount. It has an effect.

[Brief description of drawings]

FIG. 1 is a block diagram showing a manufacturing process of a disk using an aluminum alloy wrought plate material of the present invention.

FIG. 2 is a block diagram showing a manufacturing process of a rim using the aluminum alloy wrought plate material of the present invention.

FIG. 3 is a cross-sectional view showing an example of an automobile wheel obtained by the manufacturing method of the present invention.

[Explanation of symbols]

 1 disc 2 rim 3 joint 4 wheel

Claims (1)

[Claims] 1. Mg: 0.8 to 1.2%, Si: 0.40 to 0.2%.
8%, Cu: 0.15 to 0.40%, Cr: 0.04 to 0.35
% As a main component, including Fe: 0.7% or less, Mn: 0.15% or less, Zn: 0.25% or less, Ti: 0.15% or less,
The balance is composed of Al and inevitable impurities, and an aluminum alloy wrought sheet material recrystallized by annealing is formed into a rim and a disc having a required shape, and the rim and the disc are assembled and welded. Then 516 ° C
Solution treatment is performed at ~ 579 ° C, and then at room temperature or 15
A method for manufacturing an automobile wheel using an aluminum alloy wrought sheet material, which comprises performing age hardening treatment at a temperature of 4 ° C to 166 ° C.