JPH05131283A - Butt welding method with laser beam - Google Patents

Abstract

PURPOSE:To prevent the rough state of surface bead from generation by shifting wateriols to be welded by the prescribed distance from the mutual butting, and irradiating the laser beam inclined by the prescribed angle. CONSTITUTION:Wateriols 2, 2 to be welded are shifted by 0-0.8 mm from the butting position, inclined by 3-9 degree and irradiated with the laser beam 3. Therefore, even if the butting surfaces 2, 2a of the wateriols 2, 2 to be welded are not mutually brought into contact closely, they are surely melt in from the neighborhood with the irradiating laser beam 3 without passing through the clearance of mutual butting surfaces.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for laser-welding welded materials such as columns and diaphragms that are arranged in abutment with each other, or plates.

[0002]

2. Description of the Related Art Conventionally, laser welding of joints of various materials to be welded has been performed (see, for example, Japanese Patent Laid-Open No. 3-13288), but as shown in FIGS. It is also practiced to dispose the materials 1 and 1 to be welded such as plate materials in abutting relation with each other and laser weld the joint portion.

At the time of butt welding using such a laser, as shown in FIG.
(Abutting surface) If the laser beams are radiated toward the joint surfaces 1a, 1a, the laser may not pass through the joint portion or the laser may pass through the joint portion when the laser is irradiated toward the joint surfaces 1a, 1a. As shown in FIG. 3 (c), the joint surfaces 1a, 1a cannot be melted only by filling the gap between the materials to be welded 1, 1 and a recess 1b is formed, resulting in a rough surface bead state.

Therefore, conventionally, various means such as increasing the laser output, reducing the processing speed, and using a hot wire have been used.

[0005]

However, an increase in laser output and a reduction in processing speed cause a decrease in welding efficiency, and when a hot wire is used,
There were problems such as difficult welding and high processing costs.

The present invention is intended to solve such problems, and an object thereof is to provide a laser butt welding method capable of preventing the occurrence of surface bead state roughness without changing the laser welding conditions. And

[0007]

In order to achieve the above object, a butt welding method using a laser of the present invention is a method for welding the materials to be welded in a butt arrangement when welding the materials to be welded to each other by laser. The irradiation position of the laser is arranged while being displaced by a predetermined distance from the butting position of the materials to be welded, and the irradiation direction of the laser to the materials to be welded is predetermined with respect to the abutting surface of the materials to be welded. The feature is that they are placed at an angle.

By arranging the material to be welded with respect to the laser, the irradiation direction of the laser and the abutting surface of the materials to be welded may be arranged at the predetermined angle.

[0009]

In the above-described laser butt welding method of the present invention, the laser is displaced from the butt position on the material to be welded and irradiated with being inclined with respect to the butt surface, so that the materials to be welded should be welded to each other. Even when the two are not in close contact with each other, the laser at the start of irradiation does not pass through the gap between the abutting surfaces, and the joint between the materials to be welded can be surely melted from its peripheral portion.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A laser butt welding method as an embodiment of the present invention will be described below with reference to the drawings.
Is a side view showing the butt arrangement state of the material to be welded and the laser irradiation state, and FIG. 2 is a side view showing a modified example of the butt arrangement state of the material to be welded and the laser irradiation state.

In this embodiment, as shown in FIG. 1, when the butting surfaces 2a, 2a of the materials to be welded 2 are arranged to face each other and are welded by the laser 3, these materials to be welded 2 The irradiation position of the laser 3 on 2 is a predetermined distance (for example, 0 to 0. 0 from the abutting position of the materials 2 and 2 to be welded).
8mm) and the materials to be welded 2, 2
The irradiating direction of the laser 3 on the abutting surface 2 which is arranged to face
It is arranged so as to be inclined with respect to a and 2a by a predetermined angle (for example, 3 to 9 degrees).

The laser welding conditions are, for example, laser output of 5 kW, ring mode, focus position of -1 mm, processing speed of 1.5 m / min, coaxial shield system, and the shielding gas is N ₂ gas with a flow rate of 30 liters / min. To use. The material to be welded 2 is a hot-dip zinc-5% aluminum alloy-plated steel sheet having a thickness of 6 mm. Under such conditions, for example, the above-mentioned predetermined distance is set to 0.5 mm and the predetermined angle is set to 7 degrees.

In FIG. 1, by adjusting the irradiation position and the irradiation direction of the laser 3 with respect to the materials 2 and 2 to be welded,
Although the deviation of the predetermined distance and the inclination of the predetermined angle are set, as shown in FIG. 2, the materials to be welded 2 and 2 are displaced with respect to the laser 3 by a predetermined distance and are inclined by a predetermined angle. The irradiation position and the irradiation direction of the laser 3 may be adjusted.

Thus, in this embodiment, as shown in FIG. 1 or 2, the laser 3 is displaced from the position of the abutting surfaces 2a, 2a with respect to the materials to be welded 2, 2 and the abutting surfaces 2a, 2a. Irradiate with an inclination with respect to 2a.

As a result, even if the butting surfaces 2a, 2a of the materials 2, 2 to be welded are not in close contact with each other,
At the start of irradiation, the laser 3 does not pass through the gap between the abutting surfaces 2a, 2a, and the joining portion between the materials to be welded 2 is surely melted from its peripheral portion.

Therefore, it is possible to reliably prevent the occurrence of surface beading roughness without changing the laser welding conditions, and to prevent the deterioration of welding efficiency and the high processing cost as in the prior art, and the quality without surface roughness. The advantage is that high welding can be performed.

The present invention is not limited to the above-mentioned embodiments, and is included in the scope of the present invention even if there are design changes and the like without departing from the gist of the present invention. For example, in the above embodiment, as the material to be welded, the case of butt welding of steel plates has been described, but the method of the present invention is not limited to this, and various other butt portions (for example, welded column And the diaphragm), the same effect can be obtained as in the above embodiment.

[0018]

As described above in detail, according to the laser butt welding method of the present invention, the laser is irradiated to the material to be welded while being displaced from the butt position and inclined with respect to the butt surface. Even if the materials to be welded are not in close contact with each other, it is possible to reliably melt the joint between the materials to be welded from the periphery, so that the surface bead state can be maintained without changing the laser welding conditions. Roughness can be prevented, and high quality welding can be achieved without lowering welding efficiency and increasing processing costs.

[Brief description of drawings]

FIG. 1 is a side view showing a butt arrangement state and a laser irradiation state of materials to be welded in a butt welding method using a laser as one embodiment of the present invention.

FIG. 2 is a side view showing a modified example of a butt arrangement state of a material to be welded and a laser irradiation state in the present embodiment.

FIG. 3A is a cross-sectional view showing a state in which the butt portions of the materials to be welded are not in close contact with each other, and FIG. 3B is a welding process when conventional butt welding with a laser is performed in the state shown in FIG. 3A. Sectional drawing which shows a state, (c) is a sectional view which shows the welding state after the butt welding performed as shown in (b).

[Explanation of symbols]

 2 Material to be welded 2a Butt surface (joint surface) 3 Laser

Claims (2)

[Claims] 1. A butt-welding method for welding materials to be welded arranged in a butt together with a laser, wherein a laser irradiation position on the materials to be welded is shifted by a predetermined distance from a butt position of the materials to be welded. A butt welding method using a laser, wherein the laser irradiation direction to the materials to be welded is inclined with respect to the abutting surfaces of the materials to be welded by a predetermined angle. 2. The tilted arrangement of the material to be welded with respect to the laser causes the irradiation direction of the laser and the abutting surface of the materials to be welded to be arranged at the predetermined angle. The butt welding method using a laser according to claim 1.