JP2003181530A - Method for manufacturing aluminum alloy extruded material having excellent bending workability and energy absorbing characteristics - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aluminum alloy extruded material having excellent bending workability and energy absorbability. <P>SOLUTION: A method for manufacturing the aluminum alloy extruded material having excellent bending workability and energy absorbability comprises steps of extruding an aluminum alloy containing by mass% one or more types selected from the group composed of 0.4 to 1.0% of Si, 0.5 to 1.0% of Mg, 0.05 to 0.6% of Cu, 0.1 to 0.4% of Fe, 0.005 to 0.1% of Ti, 0.0001 to 0.004% of B, and further 0.02 to 0.6% of Mn, 0.02 to 0.3% of Cr, 0.02 to 0.25% of Zr and a composition containing the residue of Al and unavoidable impurities at an extruding speed V (m/s) decided according to a distance X (m) from the end of a die to a cooling unit, and then regulating a quenching delay time t (=X/V) falling within a range of 0≤t≤12 s. <P>COPYRIGHT: (C)2003,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] [0001] The present invention relates to the transportation of automobiles and the like.
Absorbs external impact energy during collision in transmitter
For producing bumpers, frames, etc.
For optimum bending workability and energy absorption characteristics as a material
Regarding the manufacturing method of excellent aluminum alloy extruded material
It is. [0002] 2. Description of the Related Art Generally, transportation vehicles such as automobiles collide.
In this case, the shock energy received from the outside is
Reinforcing parts such as bumpers and frames to protect passengers
Is known to be equipped with these
The material absorbs the collision energy by deforming at the time of the collision
It is also known to work. These reinforcing members are
Press-formed cold-rolled steel sheets,
Need to reduce body weight to reduce vehicle emissions and improve fuel efficiency
In response to this demand, the steel plate
Use lighter aluminum extruded material instead of product
Is becoming active. Used as these reinforcing members
The extruded aluminum material used is JIS6063 alloy
Al-Mg-Si based aluminum alloy such as
Uniform by holding at 80-560 ° C for 1-12 hours
Extrusion speed at 460-560 ° C.
Degree: By passing a die at 0.1 to 0.3 m / sec.
Extruded material that has been extruded and passed through a die is 4m or more
Spray cooling water onto the extruded material at a distance
After quenching delay time: Rapid cooling to 35 seconds,
After that, it is kept in a temperature range of 150 to 250 ° C for 1 to 24 hours.
Manufactured by aging treatment. But
Al-Mg-Si based aluminum alloy (for example, J
Extruded material of IS6063 alloy) is more cost effective than cold rolled steel sheet.
From the point where the
Studies have been made to reduce the thickness. [0003] However, the conventional Al-
Extruded material obtained by thinning Mg-Si-based aluminum alloy
May cause cracks on the outer peripheral surface during bending and
Cracks are likely to occur during compression deformation at the time, and cracks occur once
Then, since the subsequent shock is not absorbed, the energy
-There is a problem that absorption efficiency becomes extremely low.
Was. [0004] Means for Solving the Problems Accordingly, the present inventors have:
Cracks during bending and compression deformation during collision
Workability and energy absorption without cracking
Extruded Al-Mg-Si based aluminum alloy
Researched to obtain the material. As a result, (a)
(Hereinafter,% indicates mass%), Si: 0.4 to 1.0
%, Mg: 0.5 to 1.0%, Cu: 0.05 to 0.6
%, Fe: 0.1-0.4%, Ti: 0.005-0.
1%, B: 0.0001 to 0.004%
In addition, Mn: 0.02-0.6%, Cr: 0.02-0.
3%, one or two of Zr: 0.02 to 0.25%
Species or more, and the remainder consists of Al and unavoidable impurities.
Al-Mg-Si based aluminum alloy
Extrusion by passing through a die after homogenization
It was extruded when it was processed and then cooled rapidly.
Time required for rapid cooling (hereinafter, quenching after extrusion)
The shorter the delay time, the shorter the bending workability and energy
-The absorption characteristics are improved. (B) In this case, the extrusion speed
V (m / sec), distance X from die end to cooling device
Quenching delay time after extrusion determined by (m)
Is t (= X / V), it is most preferable that t = 0.
Preferably, adjust the upper limit of the delay time to 12 seconds.
The extruded aluminum alloy manufactured by
And has excellent energy absorption properties.
0 ≦ t ≦ 12 seconds, since it functions well
Is preferred. [0005] The present invention has been made based on such knowledge.
And Si: 0.4 to 1.0%, Mg: 0.1%.
5 to 1.0%, Cu: 0.05 to 0.6%, Fe: 0.
1 to 0.4%, Ti: 0.005 to 0.1%, B: 0.
0001-0.004%, and Mn: 0.
02-0.6%, Cr: 0.02-0.3%, Zr:
Contains one or more of 0.02 to 0.25%
And the remainder has a composition consisting of Al and unavoidable impurities
The aluminum alloy is extruded at an extrusion speed V (m / sec)
Is determined by the distance X (m) from the edge to the cooling device.
Quenching delay time t (= X / V) after extrusion is 0 ≦ t
Bending process adjusted to be within ≦ 12 seconds
Alloy with excellent heat resistance and energy absorption properties
An extruded material manufacturing method. When manufactured by the method of the present invention, bending
Alloy with excellent heat resistance and energy absorption properties
The reason that an extruded material is obtained is that the method of the present invention
Very short time from work to quenching by water cooling
Therefore, the crystal structure of the extruded material becomes finer and
Susceptibility to cracks along grain boundaries during processing and collision
And therefore bendability and energy absorption
Extruded aluminum alloy with excellent yield characteristics can be obtained
it is considered as. The bending workability and energy absorption of the present invention
Aluminum alloy extruded material with excellent yield characteristics
Of extruded Al-Mg-Si aluminum alloy
The composition of the components and the cooling conditions are limited as described above.
State the reason. (A) Al-Mg-Si based aluminum alloy
Component composition of extruded gold Si and Mg: These components coexist with M
g_TwoProduct that precipitates Si in the base material and improves the strength of the alloy.
Having a Si content of less than 0.4% and / or
Is that if the Mg content is less than 0.5%,
And the desired strength cannot be secured.
On the other hand, when the Si content is 1.0% and / or the Mg content is
Exceeding 1.0% results in reduced extrusion processability and bending.
Cracking due to deformation during processing and collision
This is not preferred. Therefore, the content of Si is
0.4-1.0%, Mg content is 0.5-1.0%
Determined. A more preferable range of the content of Si is 0.5 to
0.9%, a more preferable range of the content of Mg is 0.5 to
0.8%. Cu: Cu forms a solid solution in an Al alloy base.
And has the effect of improving the strength, but its content
Is less than 0.05%, the effect is not sufficient.
Corrosion resistance and bending workability when contained over 0.6%
Is undesirably reduced. Therefore, Cu content
The amount is 0.05-0.6% (more preferably 0.35-
0.60%). [0010] Ti, B: These components refine the cast structure
And has the effect of preventing casting cracks.
At any content of Ti: less than 0.005%, B:
If it is less than 0.0001%, the desired effect cannot be obtained, while
Regardless of the content of Ti and B, Ti: 0.1%
And B: If contained in excess of 0.004%, huge metals
The toughness decreases due to the formation of intermetallic compounds, and during bending,
It is preferable because cracking due to deformation at the collision is likely to occur
I don't. Therefore, the Ti content is 0.005 to 0.1
% (More preferably 0.01 to 0.03%), B content
Is 0.0001 to 0.004% (more preferably 0.01 to 0.004%).
005-0.003%). Mn, Cr, Zr: These components include Al
To form an intermetallic compound, and this intermetallic compound is recrystallized
Nucleation site of Al alloy extruded material
Has the effect of miniaturization and, as a result, improves the crushing properties
Has at least one of these components
Must be contained, but each component has its lower limit
If it is less than 0.02%, the above effect can be sufficiently obtained.
On the other hand, Mn: more than 0.6%, Cr: more than 0.3%
If Zr: content exceeding 0.25%, coarse metal
Intermetallic compounds begin to form, resulting in poor mechanical properties
It is not preferred. Therefore, the content of Mn is 0.0
2 to 0.6% (more preferably 0.04 to 0.30
%), The content of Cr is 0.02 to 0.3% (more preferable).
0.03 to 0.15%), and the Zr content is 0.02%.
To 0.25% (more preferably 0.03 to 0.15%)
Determined. (B) Hardening delay time after extrusion In the method for producing an extruded aluminum alloy according to the present invention,
And the extrusion speed V (m / s) from the die end to the cooling device
Quenching after extrusion determined by distance X (m)
Aluminum alloy extruded material with delay time t (= X / V)
Greatly affects the bending workability and energy absorption characteristics of
And the quenching delay time t after the extrusion is 0.
Most preferably, if less than 12 seconds with the reinforcing member
Sufficient bending workability and energy absorption characteristics
Therefore, the quenching delay time t after the extrusion is 0 ≦ t ≦ 1.
Set to 2 seconds. [0013] DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples 1 to 13 and Comparative Examples 1 to
3 Dissolve the Al alloy, cast the resulting Al alloy melt,
Si: 0.95%, Mg: 0.53%, Cu: 0.57
%, Fe: 0.24%, Ti: 0.01%, B: 0.0
01%, Mn: 0.25%, the balance being Al and
It has a composition consisting of unavoidable impurities and has a diameter of 204 mm.
A billet having dimensions was produced. This billet is 54
Perform homogenization treatment at 5 ° C for 4 hours.
Of the billet that has undergone the chemical treatment using an extruder of 1650 tons
At a temperature of 500 ° C. and an extrusion speed V shown in Table 1.
Hot extrusion process under the conditions, from the die end of the extruder
Change the distance X to the cooling position as shown in Table 1.
The quenching delay time t after extrusion is set to 0 to 15 seconds.
And water cooling at an average cooling rate of 200 ° C / sec.
After that, when the temperature is kept at 180 ° C. for 8 hours
Cross section dimension is 54mm x 70m
m, wall thickness: 2mm
Was. This hot extrusion process is performed at the mold exit of the hot extrusion device.
Prepare a device equipped with a water-cooling chamber at
Water-cooling after hot extrusion of the treated billet
Using a device that can change the distance
It was done. [0014] Extrusion of the square pipe thus obtained
Conducted by conducting tests on the following conditions for the shaped bar
Examples 1 to 13 and Comparative Examples 1 to 3 were performed, and the results were tabulated.
1 is shown. Tensile test It is specified in JIS Z 2201 from a square pipe shaped extruded material.
Create a tensile test piece (No. 4 test piece) and pull it
Speed: 10 mm / min (strain speed: 3.3 × 10
^-3S^-1A tensile test is performed under the conditions of
The force and elongation were determined, and the results are shown in Table 1. Bending test JIS B 2248-1 from extruded square pipe
A bending test piece specified in 975 is prepared, and this test piece is
Perform a U-shaped bending test with a bending radius of 11 mm, outside the test piece.
Investigated whether cracks occurred on the surface and the results are shown in Table 1.
did. [0016] Static compression test Cut out the extruded shape of square pipe into length: 300mm
To make a square pipe for crushing.
Has a length of 150 mm and a width of 150 mm.
To produce a crushed test piece by MIG welding
Crushing speed: 50 mm / min, pressure from both ends of this crushed test piece
Crush stroke: crushed under the condition of 180 mm,
The presence or absence of cracks and the absorbed energy are measured, and the results are
The results are shown in Table 1. [0017] [Table 1] From the results shown in Table 1, the post-extrusion firing
Perform under the condition that the insertion delay time t is in the range of 0 to 12 seconds.
Examples 1 to 13 show bending workability and energy absorption characteristics.
Quenching delay time t after extrusion is 1
If more than 2 seconds, bending workability and energy absorption
Is undesirable because at least one of them becomes inferior
You can see that. Examples 14 to 30 and Comparative Examples 4 to 12 The Al alloy is melted, and the obtained molten Al alloy is cast and
A billet having a diameter of 204 mm was manufactured. This
Of the billet at 545 ° C for 4 hours
And the billet subjected to this homogenization treatment is 1650 tons.
Using an extruder, temperature: 500 ° C, extrusion speed
V: Hot extrusion was performed at 0.25 m / sec.
The distance X from the die end of the unloader to the cooling position is 1.5 m
Quenching delay time t: 6 seconds after extrusion
After cooling with water, continue at 8:00 at 180 ° C
By performing the aging treatment for the holding time, the composition shown in Table 2 is obtained.
The composition has a cross-sectional dimension of 54 mm x 70 mm and a wall thickness of:
Extruded profiles a to z of 2 mm square pipe shape were produced. The obtained square pipe-shaped extruded members a to z are
Tension under the same conditions as in Examples 1 to 13 and Comparative Examples 1 to 3
Example by performing test, bending test and crush test
14 to 30 and Comparative Examples 4 to 12 were carried out, and the results were obtained.
The results are shown in Table 3. [0021] [Table 2][0022] [Table 3] From the results shown in Tables 2 and 3, Example 14
The composition whose composition is within the range of the present invention is prepared in
Extruded pipes have good bending workability and energy absorption.
Although the yield characteristics are excellent, the samples produced in Comparative Examples 4 to 12
Square pipe-shaped push having a component composition outside the scope of the invention
The extruded section is one of the bending workability and energy absorption characteristics.
Unfavorable because at least one becomes inferior
I understand. [0024] According to the present invention, as described above,
Extruded material has excellent bending workability and energy absorption properties
Using the extruded material produced by the method of the present invention.
Suitable as reinforcement material for automobiles such as bumpers and frames
Lower cost, lighter weight and energy saving
That have excellent industrial effects, such as contributing to energy
It is.

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Claims (1)

Claims 1. In mass% (hereinafter,% indicates mass%), S
i: 0.4 to 1.0%, Mg: 0.5 to 1.0%, C
u: 0.05 to 0.6%, Fe: 0.1 to 0.4%, T
i: 0.005 to 0.1%, B: 0.0001 to 0.0
0.4%, and further, Mn: 0.02-0.6%,
Cr: 0.02-0.3%, Zr: 0.02-0.25
% Of an aluminum alloy having a composition consisting of Al and unavoidable impurities, with the extrusion speed V (m / sec) being the distance X (m) from the die end to the cooling device. The quenching delay time t (= X / V) after extrusion determined by the formula (1) is adjusted so as to be within the range of 0 ≦ t ≦ 12 seconds. Manufacturing method of extruded aluminum alloy.