JP2002105570A - Aluminum alloy extruded material for machine parts and having excellent corrosion resistance, strength, machinability and clinching property - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an aluminum alloy extruded material for producing various machine parts and having excellent corrosion resistance, strength, machinability, particularly drill workability and clinching properties. SOLUTION: This aluminum alloy extruded material for machine parts has a composition containing 1.5 to 5.0% Si, 0.4 to 1.0% Mg and 0.05 to 0.50% Zn, if required, further containing one or more kinds selected from 0.03 to <0.4% Mn, 0.03 to 0.50% Cr and 0.03 to 0.30% Zr, further containing 0.03 to 0.4% Cu, if required, and further containing 0.01 to 0.1% Sr, if required, and the balance Al with inevitable impurities.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to corrosion resistance, strength,
The present invention relates to an aluminum alloy extruded material for manufacturing various machine parts having excellent machinability, particularly drilling and clinching properties, and particularly relates to an anti-lock brake system housing (hereinafter referred to as an ABS housing),
The present invention relates to an aluminum alloy extruded material that is most suitable as a material of a mechanical component that is frequently used for drilling when manufacturing a hydraulic piping connector or the like.

[0002]

2. Description of the Related Art Conventionally, as a material of a mechanical component which is frequently used for drilling such as an ABS housing and a hydraulic piping connector, a material having a medium or higher mechanical strength and a good cutting property has been widely used. Have been. JIS6061 alloy (Si: 0.4-0.8%, Fe:
0.7% or less, Cu: 0.15 to 0.4%, Mn: 0.1 to 0.4%
15% or less, Mg: 0.8 to 1.2%, Cr: 0.04
0.35%, Zn: 0.25% or less, Ti: 0.15
% Or less, with the balance being Al and inevitable impurities) or JIS6262 alloy (Si: 0.4 to 0.8%, C
u: 0.15 to 0.4%, Mg: 0.8 to 1.2%, P
Aluminum alloy extruded materials containing b: 0.4 to 0.7%, Bi: 0.4 to 0.7%, and the balance being Al and unavoidable impurities) are widely used. However, although the JIS6262 alloy has excellent machinability, Pb,
Bi is contained. In particular, in recent years, recycling of Al alloys has been widely performed, and it is not preferable that Pb or Bi harmful to the human body is mixed in recycled products. Therefore, in recent years, JIS6061 alloys which do not contain Pb or Bi even if sacrificing machinability to some extent have been used as extruded aluminum alloys for various mechanical parts.

[0003]

However, the ABS housing installed in the hood of the automobile is exposed to air containing automobile exhaust gas sucked for radiator cooling. Aluminum housing and other materials that require corrosion resistance because they are easily corroded by exposure to air, and aluminum that is used as a material for machine parts such as ABS housing that require drilling at very narrow intervals with multiple holes Extruded alloy materials require properties that are excellent in machinability, especially drillability. Furthermore, after performing drilling with a drill, the valve is inserted into the hole, and the valve is swaged (clinching) to perform the fixing operation. However, it is preferable if a defect such as a crack occurs in the swaged portion. No (below,
The characteristic that a defect such as a crack does not occur in the swaged portion by swaging is called clinching property). The present invention provides an extruded aluminum alloy material having excellent corrosion resistance, medium or higher mechanical strength, excellent machinability, especially drillability and clinchability, which can be used as a material for manufacturing mechanical parts such as an ABS housing. To provide.

[0004]

Means for Solving the Problems The present inventors have found that corrosion resistance,
As a result of conducting research to obtain an aluminum alloy extruded material having a medium or higher mechanical strength, and also having excellent machinability, especially drilling workability and excellent clinchability, (a) mass% ,% Indicates mass%), S
i: 1.5 to 5.0%, Mg: 0.4 to 1.0%, Z
An extruded material composed of an Al alloy containing n: 0.05 to 0.50% and a balance of Al and unavoidable impurities has corrosion resistance, moderate or higher mechanical strength, and further excellent cutting performance. It has excellent clinching properties and is suitable for materials of various machine parts.
Mn: 0.03-0.
Less than 4%, Cr: 0.03 to 0.50%, Zr: 0.0
By containing at least one of 3 to 0.30%, the machinability is further improved.
Cu: 0.03 to 0.4% in the Al alloy of (b)
When Cu is contained, Cu forms a solid solution in the base material to improve the strength, and further improves the chip hardening ability in cutting to improve the strain hardening ability. (D) The above (a) to (c)
It has been found that when Sr is further contained in the Al alloy of 0.01 to 0.1%, eutectic Si can be refined to ensure strength, machinability and clinching properties.

[0005] The present invention has been made based on such findings, and (1) Si: 1.5 to 5.0%, M
g: 0.4-1.0%, Zn: 0.05-0.50%, with the balance being an Al alloy having a composition consisting of Al and unavoidable impurities, to provide corrosion resistance, strength, machinability and clinching properties. Excellent extruded aluminum alloy material for machine parts, (2) Si: 1.5-5.0%, Mg: 0.4-
1.0%, Zn: 0.05 to 0.50%, Mn: 0.03 to 0.4%, Cr: 0.03 to 0.5
0%, one or two of Zr: 0.03 to 0.30%
Extruded aluminum alloy for machine parts having excellent corrosion resistance, strength, machinability and clinching property, comprising an Al alloy having a composition comprising Al and unavoidable impurities, the balance comprising Al or more, and (3) the above (1) or (1). 2) A described
(1) an aluminum alloy extruded material for a mechanical component having excellent corrosion resistance, strength, machinability and clinching property, comprising an Al alloy having a composition containing 0.03 to 0.4% of Cu in addition to (1), (2) or (3)
Sr: 0.01 to 0.1% in addition to the described Al alloy
And an aluminum alloy extruded material for mechanical parts having excellent corrosion resistance, strength, machinability and clinching properties, comprising an Al alloy having a composition comprising Al and unavoidable impurities.

A having the composition described in the above (1) to (4)
Extruded aluminum alloys made of 1 alloy are all excellent in corrosion resistance, strength, machinability and clinching property, but Mn: less than 0.03 to 0.4%, Cr: 0.03 to less.
The extruded aluminum alloy according to the above (2), which contains at least one of 0.50% and Zr: 0.03 to 0.30%, has a fibrous structure to further improve the machinability. The aluminum alloy extruded material composed of an Al alloy containing 0.03 to 0.4% of Cu in the Al alloy according to the above (2) further improves the chip breaking property while maintaining a fibrous structure. In addition, when Sr: 0.01 to 0.1% is further contained, the eutectic Si structure becomes finer while maintaining the fibrous structure, so that the strength, machinability and clinching are improved. It has been found that it is preferable because the property is further improved.

The present invention has been made based on this finding, and (5) Si: 1.5 to 5.0%, M
g: 0.4 to 1.0%, Zn: 0.05 to 0.50%, Mn: 0.03 to less than 0.4%, Cr:
0.03 to 0.50%, Zr: contains one or more of 0.03 to 0.30%, and the remainder contains Al and unavoidable impurities, and a fibrous structure as an internal structure. Aluminum alloy extruded material for mechanical parts having excellent corrosion resistance, strength, machinability and clinching properties, comprising: an Al alloy having: (6) Si: 1.5 to 5.0%, Mg:
0.4-1.0%, Zn: 0.05-0.50%, Mn: 0.03-0.4%, Cr: 0.
0.3 to 0.50%, Zr: 0.03 to 0.30%, contains one or more of them, and further contains Cu: 0.03%.
Extrusion of aluminum alloy for machine parts with excellent corrosion resistance, strength, machinability and clinching properties, consisting of an Al alloy containing up to 0.4% with the balance being Al and unavoidable impurities, and having an internal structure having a fibrous structure. Timber,
(7) Si: 1.5 to 5.0%, Mg: 0.4 to 1.0
%, Zn: 0.05 to 0.50%.
n: 0.03 to less than 0.4%, Cr: 0.03 to 0.5
0%, Zr: a composition containing one or more of 0.03 to 0.30%, further containing 0.01 to 0.1% of Sr, and the balance consisting of Al and unavoidable impurities. ,
And an aluminum alloy extruded material for machine parts having excellent corrosion resistance, strength, machinability and clinching property, comprising an Al alloy having a fibrous structure as an internal structure, (8) Si:
1.5-5.0%, Mg: 0.4-1.0%, Zn:
0.05-0.50%, and Mn: 0.03
To less than 0.4%, Cr: 0.03 to 0.50%, Zr:
It contains one or more of 0.03 to 0.30%, further contains Cu: 0.03 to 0.4%, and further contains Sr: 0.01 to 0.1%. , An aluminum alloy extruded material for mechanical parts excellent in corrosion resistance, strength, machinability and clinching properties, composed of an Al alloy having a fibrous structure as an internal structure, and a composition consisting of Al and unavoidable impurities. is there.

The corrosion resistance and strength described in the above (1) to (8)
An extruded aluminum alloy for machine parts having excellent machinability and clinching properties is most suitably used as a material for producing an ABS housing. Therefore, the present invention is characterized by (9) an ABS housing made of an extruded aluminum alloy material for machine parts having excellent corrosion resistance, strength, machinability and clinching properties according to the above (1) to (8). is there.

The reasons why the composition of the extruded aluminum alloy material for machine parts of the present invention, which is excellent in corrosion resistance, strength and machinability, particularly excellent in drillability and clinchability, are limited as described above.

Si: Si has the effect of precipitating Mg ₂ Si in the matrix by coexisting with Mg and contributing to the improvement of the strength of the alloy. Further, excess Si is added to the balanced composition of Mg ₂ Si. By the presence of an appropriate amount, the Si crystallization phase is uniformly dispersed in the mother phase, so that a further strengthening effect and an effect of improving machinability, especially drilling workability can be obtained, but if the Si content is less than 1.5%, The above effect is not sufficient, while S
If the i content exceeds 5.0%, the moldability and corrosion resistance are reduced, and the excess Si phase causes excessive wear of the cutting tool, shortening the tool life. Therefore, the content of Si is set to 1.5 to 5.0%. The more preferable range of the content of Si is 2.0 to 3.0%.

Mg: Mg has an effect of precipitating Mg ₂ Si in the base material by coexisting with Si and improving the strength of the alloy. However, when the Mg content is less than 0.4%, the above-mentioned effect is sufficient. On the other hand, if the Mg content exceeds 1.0%, the moldability and corrosion resistance decrease, which is not preferable. Therefore, the content of Mg is set to 0.4 to 1.0%.
A more preferred range for the Mg content is 0.50 to 0.80.
%.

Zn: Zn is added because it has the effect of improving the corrosion resistance, particularly pitting corrosion resistance, of the Al alloy, and also has the effect of reducing the severe wear of the drill due to the addition of a large amount of Si. If it is less than 05%, the desired effect cannot be obtained, while if it exceeds 0.50%, no further effect can be expected. Therefore, Zn: 0.05-
0.50% (more preferably 0.1 to 0.2%).

Mn, Cr, Zr: Each of these components forms compound particles with Al, suppresses recrystallization during extrusion and develops a fibrous structure, thereby increasing the strength and machinability of the alloy, especially drilling. It is added because it has an effect of enhancing workability, but Mn: less than 0.03%, Cr: 0.0
If the content is less than 3% and Zr: less than 0.03%, the desired effects cannot be obtained. On the other hand, Mn: 0.40% or more, Cr:
Even if the content exceeds 0.50% and the content of Zr exceeds 0.30%, no further effect can be expected. Therefore, Mn: 0.
03 to less than 0.40% (more preferably 0.1 to 0.3%)
%), Cr: 0.03 to 0.50% (more preferably 0.2 to 0.3%), Zr: 0.03 to 0.30 (more preferably 0.05 to 0.2%)% Determined.

Cu: Cu forms and disperses fine precipitates by heat treatment, and contributes to the improvement of strength. In addition, Cu improves cutting ability in cutting to improve strain hardening ability. However, if the content is less than 0.03%, the effect cannot be sufficiently obtained. On the other hand, if the Cu content exceeds 0.4%, the corrosion resistance and the formability are reduced. Not preferred. Therefore, the content of Cu is set to 0.03 to 0.4%. C
The more preferable range of the content of u is 0.20 to 0.40%.
It is.

Sr: Sr is added because it has the effect of improving the strength and machinability of the alloy, particularly the drillability, by making eutectic Si finer.
If it is less than 1%, the desired effect cannot be obtained, while 0.10%
If it exceeds, a coarse intermetallic compound containing Sr is crystallized, which becomes a hard spot and lowers the machinability, which is not preferable. Therefore, the content of Sr is 0.01 to
0.1% (more preferably 0.04 to 0.08%).

Si: 1.5-5.0%, Mg: 0.4-
An Al alloy containing 1.0%, Zn: 0.05 to 0.50%, and the balance being Al and unavoidable impurities is further added to Mn: 0.03 to less than 0.4%, Cr: 0.
When one or more of Zr: 0.03 to 0.30% and Zr: 0.03 to 0.30% are contained, the internal structure becomes a fibrous structure, and the strength, machinability, especially drillability and clinching property are reduced. It will improve further, but the reason is not clear. However, in the fibrous structure, the distance between the grain boundaries is smaller than that of the recrystallized structure, so that excess Si approaches and disperses in the base material, thereby further improving the strength and clinching properties. It is considered that the cutting crack generated at the Si grain during drilling is easily propagated and the drilling workability is improved.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION An Al alloy having the composition shown in Tables 1 and 2 is melted and cast to produce a billet having a diameter of 225 mm, and the billet is homogenized at 510 ° C. for 6 hours. The extruded rod having a cross-sectional dimension of 40 mm x 100 mm was produced by hot-extruding the billet subjected to the homogenization treatment at a temperature of 500 ° C. In this hot extrusion process, a device having a water cooling chamber installed at the mold outlet of the hot extrusion device is prepared, and the billet that has been subjected to the homogenization treatment is subjected to water-cooled extrusion simultaneous quenching immediately after the hot extrusion process. Made by The extruded rods thus obtained were subjected to artificial aging treatment at 180 ° C. for 8 hours to obtain extruded materials 1 to 30 of the present invention and comparative extruded material 1
~ 4 and a conventional extruded material were prepared.

Extruded materials 1 to 30 of the present invention, comparative extruded material 1
４4 and a conventionally extruded material were subjected to a tensile test, a drilling test, and a corrosion resistance test under the following conditions.

Tensile test A tensile test piece (No. 4 test piece) specified in JISZ 2201 5.1 (c) was prepared from the extruded materials 1 to 30, comparative extruded materials 1 to 4, and the extruded material of the present invention, and was subjected to a tensile test. Speed: 10 mm / min (strain speed: 3.3 × 10
^-3 s ^-1 ), a tensile test was performed to determine the tensile strength, proof stress, and elongation. The results are shown in Tables 1 and 2, and the strength and clinching property were evaluated. The larger the elongation, the less the occurrence of cracks in caulking, so that it can be evaluated as having excellent clinching properties.

Drilling test The extruded materials 1 to 30, comparative extruded materials 1 to 4 and the conventional extruded material of the present invention were subjected to a drill having a diameter of 4 mm in the length direction and a direction perpendicular to the length direction by using a drill having a diameter of 4 mm. 200
Drilling was performed under the conditions of 0 rpm and a feed rate of 400 mm / min, and the average of the lengths of 100 chips was obtained. The results are shown in Tables 1 and 2, and the drillability was evaluated. The smaller the average value of the length of 100 chips is, the better the drill workability is.

Corrosion resistance test For the extruded materials 1 to 30 of the present invention, the comparative extruded materials 1 to 4 and the conventional extruded materials, the weight loss per unit area by the SST test (spraying 5% saline solution at 35 ° C.) for 480 hours was measured. The results were shown in Tables 1 and 2, and the corrosion resistance was evaluated.

[0022]

[Table 1]

[0023]

[Table 2]

From the results shown in Tables 1 and 2, the extruded materials 1 to 30 of the present invention show excellent tensile strength, proof stress and elongation as compared with conventional extruded materials, and therefore have excellent strength and clinchability. Further, it can be seen that the drilling workability was excellent because the length of the chips was short, and the corrosion resistance was also excellent. It can also be seen that the comparative extruded materials 1-4 that do not satisfy the conditions of the present invention exhibit at least one undesirable property.

[0025]

As described above, the extruded materials 1 to 5 of the present invention can be used.
No. 30 is superior in corrosion resistance, strength and clinching property to conventional extruded material, and is excellent in drill workability which is a kind of machinability.
It is ideal as a material for machine parts that are frequently used for drilling, such as housings and hydraulic piping connectors.
It has excellent industrial effects.

Claims (5)

[Claims] 1. In mass% (hereinafter,% indicates mass%),
Si: 1.5 to 5.0%, Mg: 0.4 to 1.0%, Z
n: aluminum for mechanical parts having excellent corrosion resistance, strength, machinability and clinching characteristics, comprising 0.05 to 0.50%, the balance being an Al alloy having a composition consisting of Al and unavoidable impurities. Extruded alloy. 2. Si: 1.5-5.0%, Mg: 0.4
1.0%, Zn: 0.05 to 0.50%, Mn: 0.03 to less than 0.4%, Cr: 0.03 to
0.50%, Zr: one or more of 0.03 to 0.30%, and the balance is made of an Al alloy having a composition of Al and inevitable impurities, corrosion resistance, Extruded aluminum alloy for machine parts with excellent strength, machinability and clinching properties. 3. The corrosion resistance, strength, machinability, and corrosion resistance of the Al alloy according to claim 1 or 2, further comprising an Al alloy having a composition containing 0.03 to 0.4% of Cu. Extruded aluminum alloy for machine parts with excellent clinching properties. 4. The Al alloy according to claim 1, further comprising Sr: 0.01 to 0.1%, and the balance being an Al alloy having a composition comprising Al and unavoidable impurities. Extruded aluminum alloy for machine parts with excellent corrosion resistance, strength, machinability and clinching characteristics. 5. An anti-lock brake system housing made of an extruded aluminum alloy for mechanical parts having excellent corrosion resistance, strength, machinability and clinching ability according to claim 1.