JPH11156584A - Filler metal for aluminum alloy welding, and welding method for aluminum alloy element using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a welding part with excellent ductility and toughness, and improve mechanical properties of a whole welding material and the application range. SOLUTION: This filler metal contains 4-13 wt.% Si, and at least two or more kinds selected from a group of 0.05-0.5 wt.% Cr, 0.02-0.4 wt.% Ti+B (in this case, 0.01-0.2 wt.% Ti, and 0.01-0.2 wt.% B), and 0.05-2 wt.% Zr. Furthermore, it contains 0.1-1.0 wt.% one or more kinds of elements selected from a group of Ce, Y, La, and Sc at the total weight according to the necessity, and the balance of Al and inevitable impurities.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an aluminum alloy (in the present specification, an aluminum alloy is
The present invention relates to a filler metal for aluminum alloy welding used for welding aluminum (including both aluminum and aluminum alloy) materials and a welding method using the same.

[0002]

2. Description of the Related Art In recent years, lighter structures have been adopted in automobiles, railcars, ship transporting machines, and the like in order to improve fuel efficiency and increase speed. As these structural materials, aluminum alloy materials have been used in place of steel because of their light weight. These are generally made of aluminum alloy plates as outer plates such as outer and inner, extruded aluminum alloy members as skeletal structure, so-called frame structure and shock absorber for improving safety in collision, and aluminum alloy. The casting material is expected to be applied as a joint for connecting a skeletal structure formed by extruded members with a joint.

As plate materials, 5000-type and 6000-type aluminum alloys are mainly used, but in consideration of recyclability and cost advantages, 6000-type aluminum alloys are slightly superior. On the other hand, a 6000 series aluminum alloy material is widely used as an extruded member and a 4000 series aluminum alloy material is generally used as a casting material.

Conventionally, a fusion welding method such as arc welding is applied to these aluminum alloy materials. In the case of a combination of these, a filler material of JIS 4043 or JIS 4047 is taken into consideration in consideration of cracking sensitivity and the like. Is generally used.

[0005]

SUMMARY OF THE INVENTION However, JIS
A welded joint welded using 4043 or JIS 4047 filler metal has low elongation and toughness, and thus cannot be applied to a part that undergoes deformation such as bending, twisting, or tension after welding.

On the other hand, in the welding of aluminum alloy, hydrogen originating from the welding material, moisture and dirt on the surface of the filler metal, shielding gas and moisture in the atmosphere, etc. are the main causes,
There is a disadvantage that porosity and blowholes are easily generated.

[0007] The present invention has been made in view of the above problems, it is possible to obtain a welded part having excellent ductility and toughness, to improve the mechanical properties of the entire welded product, its application range It is an object of the present invention to provide a filler metal for aluminum alloy welding capable of improving the weldability and a welding method using the same.

[0008]

The first filler metal for aluminum alloy welding according to the present invention comprises Si: 4 to 13% by weight.
And Cr: 0.05 to 0.5% by weight;
i + B: 0.02 to 0.4 (provided that Ti: 0.01 to 0.2% by weight, B: 0.01 to 0.2% by weight) and Zr: 0.05 to 2% by weight It is characterized by containing at least two or more selected elements, with the balance being Al and unavoidable impurities.

A second filler metal for aluminum alloy welding according to the present invention contains Si: 4 to 13% by weight and further contains C
r: 0.05 to 0.5% by weight, Ti + B: 0.02 to 0.4 (however, Ti: 0.01 to 0.2% by weight,
B: 0.01 to 0.2% by weight) and Zr: 0.05 to 2% by weight selected from the group consisting of Ce, Y, La, and Sc. One or more selected elements are contained in a total amount of 0.1 to 1.
0 wt%, with the balance being Al and unavoidable impurities.

The welding method according to the present invention is characterized in that welding is performed using the first or second filler metal for aluminum alloy welding.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The reasons for adding components and limiting the composition of the aluminum alloy filler according to the present invention will be described below.

Si: 4 to 13% by weight Si is an element that affects the flowability of the molten metal in the weld metal portion. If the content exceeds 13% by weight, the molten metal is disturbed and a cavity is formed in the weld metal portion. On the other hand, when the content of Si is less than 4% by weight, the flowability of the molten metal in the weld metal is deteriorated, the holes in the molten metal are hardly discharged to the outside of the weld, and porosity and blowholes remain in the weld metal. Therefore, the amount of Si is set to 4 to 13% by weight.

Cr: 0.05 to 0.5% by weight Ti + B: 0.02 to 0.4% by weight, provided that Ti:
0.01 to 0.2% by weight , B: 0.01 to 0.2% by weight Zr: 0.05 to 2% by weight Cr and Zr alone, Ti and B
When added to the material, it has the effect of refining the crystal grains. Further, these elements have an effect of improving tensile strength and elongation.

However, in a portion such as a welded portion which has rapidly undergone melting and solidification, Cr, Zr and (Ti
+ B) alone has no effect of crystal grain refinement. For this reason, at least two or more of these Cr, Zr, and (Ti + B) are added.

Further, Cr: less than 0.05% by weight, (Ti
+ B): less than 0.02% by weight, Ti: less than 0.01% by weight, B: less than 0.01% by weight, and Zr: less than 0.05% by weight, the effect of crystal grain refinement is small, and The effect of addition cannot be obtained.

On the other hand, when Cr: exceeds 0.5% by weight,
(Ti + B): more than 0.4% by weight, and Zr:
If it exceeds 2% by weight, there is a risk of embrittlement.

Therefore, Cr: 0.05 to 0.5% by weight, Ti + B: 0.02 to 0.4% by weight (however, T
i: 0.01 to 0.2% by weight, B: 0.01 to 0.
2% by weight) and Zr: 0.05 to 2% by weight. This improves the ductility of the weld.

However, when welding a portion that is subjected to more severe deformation, it is desirable to add the following elements.

The total amount of Ce, Y, La and Sc is 0.1 to
1.0% by weight Ce, Y, La and Sc all have the effect of refining crystal grains. Further, Ce, Y, La, and Sc are easily combined with hydrogen to form a hydrogen compound, and are effective in preventing the occurrence of porosity and blowholes. If the total amount of these elements is less than 0.1% by weight, the effect is small, and if it exceeds 1.0% by weight, embrittlement may be caused. Therefore, when these elements are added, the total amount is 0.1 to 1.0% by weight. By using the filler material to which these elements are added, the refinement of the crystal grains in the weld metal can be further promoted. For this reason, the filler metal of the present invention can be used for welding of a portion that undergoes significant deformation.

As a welding method applied to the welding of the aluminum material, any welding method such as MIG, TIG, laser or electron beam may be used as long as it is fusion welding. Also,
The welding conditions, for example, the output or current, welding speed, and other welding conditions may be selected according to the type of processing machine used, the thickness and shape of the workpiece, and the like. For more effective grain refinement, the filler according to the present invention can
It is desirable to use a laser welding or electron beam welding method that can provide a high power density of ⁴ W / cm ² or more. Furthermore, as the welding mode, an appropriate welding mode such as butt welding and lap welding may be selected according to the joining portion, and the present invention can be applied to any joint.

Aluminum alloy materials to be welded using the filler material of the present invention are generally JIS 4043 and J
Any combination in which the application of the filler material of IS 4047 is recommended may be used, and other aluminum alloy materials can also be welded. The form of the aluminum alloy material may be any combination of a plate material, an extruded shape material, and a cast and forged material.

[0022]

EXAMPLES Examples of the present invention will be described below in comparison with comparative examples. The welding conditions were as follows: welding method: MIG welding, test material: plate having an alloy composition of JIS A6063, plate thickness: 2 mm, type of shielding gas:
Ar gas, its flow rate: 15 liters per minute, welding method: butt welding, welding length: 300 mm, groove of butt end face of test material: I groove.

The MIG welding conditions were as follows: welding current: 120 to 130 A, welding voltage: 20 V, and welding speed: 80 cpm.

After the test materials were combined in a butt manner in pairs, the two were joined by butt welding under the above-mentioned welding conditions using a filler material having the composition shown in Table 1 below.

Next, elongation, bending, porosity defect occurrence state and crack defect occurrence state were evaluated for the weld metal part of the obtained joint. The evaluation results are shown in Table 2 below.

The elongation was measured on a JIS Z22015 No. 5 test piece with a welding line placed at the center line in a direction perpendicular to the tensile direction, and the evaluation distance was 50 mm.

The bending performance is 200 mm long and 40 mm wide.
A 180 ° bending test was conducted on the test piece with the welding line placed at the center line in the direction perpendicular to the bending and the bending R varied from 6 to 20 mm, and the crack generation limit on the surface of the weld metal was measured. did.

In the measurement of the porosity defect and the crack defect, a radiation transmission test was performed.

For evaluation, the same material was used according to JIS 4
In the joints welded by laser welding using 043 or JIS 4047, the value of each characteristic value which is superior is set as a reference value.
Excellent ones were marked with ○, and remarkably excellent ones with ◎.

As a result, in Examples 1 to 16, the composition of the filler was within the scope of the present invention, and all the evaluation results were excellent. On the other hand, Comparative Examples 17 to 39 were out of the range of the present invention, were insufficient in elongation or bendability, and had porosity defects or crack defects.

[0031]

[Table 1]

[0032]

[Table 2]

[0033]

As described above in detail, according to the filler material for aluminum alloy welding according to the present invention, a welded portion of an aluminum alloy having excellent ductility and toughness can be obtained, and a high quality welded portion can be obtained. Can be formed, and the mechanical performance of the entire structure can be improved. Therefore, the application range of the aluminum alloy material can be expanded according to the present invention, and the advantage of the weight reduction by the aluminum alloy material can be improved in a wide technical field It can be applied to For this reason, the present invention makes a great contribution to the field where weight reduction is required.

Continuing from the front page (72) Inventor Tsuyoshi Matsumoto 100-1 Urakawachi, Miyamae, Fujisawa-shi, Kanagawa Inside Kobe Steel's Fujisawa Works

Claims (4)

[Claims] 1. An alloy containing Si: 4 to 13% by weight, Cr: 0.05 to 0.5% by weight, Ti + B: 0.
02 to 0.4 (however, Ti: 0.01 to 0.2% by weight, B: 0.01 to 0.2% by weight) and Zr: 0.0
At least 2 selected from the group consisting of 5 to 2% by weight
A filler metal for aluminum alloy welding, characterized in that the filler metal contains at least one species and the balance consists of Al and unavoidable impurities. 2. Si content: 4 to 13% by weight, Cr: 0.05 to 0.5% by weight, Ti + B: 0.02%
To 0.4 (however, Ti: 0.01 to 0.2% by weight,
B: 0.01 to 0.2% by weight) and Zr: 0.05 to 2% by weight selected from the group consisting of Ce, Y, La, and Sc. One or more selected elements are contained in a total amount of 0.1 to 1.
A filler metal for aluminum alloy welding characterized by containing 0% by weight and the balance consisting of Al and unavoidable impurities. 3. Si: 4 to 13% by weight, Cr: 0.05 to 0.5% by weight, Ti + B: 0.
02 to 0.4 (however, Ti: 0.01 to 0.2% by weight, B: 0.01 to 0.2% by weight) and Zr: 0.0
At least 2 selected from the group consisting of 5 to 2% by weight
A method for welding an aluminum alloy material, wherein the welding is performed using a filler material containing at least one seed and the balance being Al and unavoidable impurities. 4. An alloy containing 4 to 13% by weight of Si, 0.05 to 0.5% by weight of Cr, and 0.02% of Ti + B.
To 0.4 (however, Ti: 0.01 to 0.2% by weight,
B: 0.01 to 0.2% by weight) and Zr: 0.05 to 2% by weight selected from the group consisting of Ce, Y, La, and Sc. One or more selected elements are contained in a total amount of 0.1 to 1.
A method for welding an aluminum alloy material, comprising: welding using the aluminum alloy filler material according to claim 2, containing 0% by weight and the balance consisting of Al and unavoidable impurities.