JP2021186861A - Welding method, welding device and product - Google Patents

Abstract

To provide a new welding method and a welding device, which can weld a plurality of overlapped members for instance, as well as a product which is welded by the welding method or the welding device.SOLUTION: In a welding method, for instance an end part in which edges extending in a second direction crossing a first direction of a plurality of members overlapped in the first direction are lined in the first direction are irradiated with laser light emitted from a laser oscillator including fiber laser, along a third direction crossing the first direction and the second direction from the outsides of the end parts, so as to weld the edges lined adjacent to each other in the first direction to each other, where a wavelength of laser light is set to be 380[nm] or more and 1200[nm] or less. Further laser light includes for instance first laser light with wavelengths of 800 [nm] or more and 1200 [nm] or less and second laser light with wavelengths of 500 [nm] or less.SELECTED DRAWING: Figure 1

Description

The present invention relates to welding methods, welding devices, and products.

Conventionally, there is known a vapor chamber in which a storage chamber for accommodating a refrigerant is provided between two stacked plate-shaped metal members, and the refrigerant is sealed by welding the peripheral portions of the two metal members. (For example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2016-355348

In the vapor chamber of Patent Document 1, two plate-shaped members are joined by a laser beam irradiated along their stacking direction. In such a configuration, for example, a flange that projects in the extending direction of the plate-shaped member in the width direction of the welded portion is provided, so that the metal member and thus the vapor chamber tends to increase in the extending direction of the plate-shaped member. There was a problem.

On the other hand, in a vapor chamber in which the two plate-shaped members are welded by a laser beam irradiated along the extending direction of the plate-shaped members toward the boundary between the two plate-shaped members, the width of the welded portion is wide. It spreads in the stacking direction of the plate-shaped members. In this case, for example, there are problems that it is difficult to apply to a case where the plate thickness is thin, and it is difficult to secure the required welding strength because the welding depth is short when the welding width is matched to the plate thickness.

Therefore, one of the problems of the present invention is, for example, a new improved welding method and welding device capable of welding a plurality of overlapping members, and welding by the welding method or the welding device. To get a product.

In the welding method of the present invention, for example, the end edges of a plurality of members overlapping in the first direction extending in the second direction intersecting the first direction are aligned with each other in the first direction. , Adjacent to the first direction by irradiating a laser beam emitted from a laser oscillator including a fiber laser along the first direction and a third direction intersecting the second direction from the outside of the end. It is a welding method for welding the edges to each other, and the wavelength of the laser beam is 380 [nm] or more and 1200 [nm] or less.

In the welding method, for example, the laser beam includes a first laser beam having a wavelength of 800 [nm] or more and 1200 [nm] or less, and a second laser beam having a wavelength of 500 [nm] or less.

In the welding method, for example, the wavelength of the second laser beam is 400 [nm] or more and 500 [nm] or less.

In the welding method, for example, the second laser beam is irradiated so as to straddle the gap of the boundary between the edges adjacent to the first direction in the first direction.

In the welding method, for example, the laser beam is swept in a sweeping direction along the second direction on the surface extending in the first direction and the second direction of the end portion, and the laser beam is swept on the surface. At least a part of the second spot formed on the surface by the second laser beam is located in front of the first spot formed on the surface by the first laser beam in the sweep direction.

In the welding method, for example, the first spot and the second spot overlap at least partially on the surface.

In the welding method, for example, on the surface, the second outer edge of the second spot surrounds the first outer edge of the first spot.

In the welding method, for example, each of the plurality of members is made of any one of a copper-based metal material, an aluminum-based metal material, a nickel-based metal material, an iron-based metal material, and a titanium-based metal material. ing.

In the welding apparatus of the present invention, for example, a laser oscillator including a fiber laser and each end edge of a plurality of members overlapping in the first direction extending in the second direction intersecting the first direction are the first. An optical head that irradiates an end portion arranged in one direction with a laser beam emitted from the laser oscillator along the first direction and a third direction intersecting the second direction from the outside of the end portion. The laser beam is a welding device that welds the edges adjacent to each other in the first direction, and the wavelength of the laser beam is 380 [nm] or more and 1200 [nm] or less.

The welding device includes, for example, a beam shaper that divides the laser beam into a plurality of beams.

The welding device, for example, sets the emission direction of the laser beam so that the laser beam moves in a sweeping direction along the second direction on the surface extending in the first direction and the second direction of the end portion. Equipped with a changing galvano scanner.

The welding device includes, for example, a rotation mechanism that rotates the end portion around a rotation axis along the first direction.

The welding device includes, for example, a detection mechanism for detecting a deviation of a spot formed on the surface of the surface by the laser beam with respect to a predetermined position, and a correction mechanism for correcting the deviation.

The product of the present invention has, for example, edges extending in the second direction, and the edges are aligned in the first direction intersecting with the second direction in the first direction. A plurality of overlapping members and a welded portion obtained by welding the end edges of the members adjacent to the first direction among the plurality of members are provided, and the welded portion is the end adjacent to the first direction. A weld metal extending from the surface extending in the first direction and the second direction of the end including the edge in the third direction intersecting the first direction and the second direction, and a position around the weld metal. The weld metal has a heat-affected zone, and the weld metal has a first portion and a second portion having a larger average cross-sectional area of crystal grains in a cross section intersecting the second direction than the first portion. , Have.

In the product, for example, the average value of the cross-sectional area of the crystal grains contained in the second portion is 1.8 times or more the average value of the cross-sectional area of the crystal grains contained in the first portion.

In the product, for example, the weld metal extends in the second direction.

In the product, for example, the aspect ratio of the weld metal to the width of the first direction of the depth in the third direction is 1 or more and 5 or less.

In the product, for example, the aspect ratio is 1.5 or more and 5 or less.

The product includes, for example, a first member and a second member joined to the first member in a state where a space is formed between the first member, and the first member and the second member. Is joined by the welded portion as the plurality of members.

The product includes, for example, a first member and a second member indirectly joined via the first member and the third member in a state where a space is formed between the first member. At least one of the first member and the third member, and the second member and the third member is joined as the plurality of members by the welded portion.

The product includes, for example, a fluid medium housed in the space, and the welded portion welds the plurality of members in a state where the welded portion prevents the fluid medium from leaking out of the space from the welded portion.

The product of the present invention has, for example, edges extending in the second direction, and the edges are aligned in the first direction intersecting with the second direction in the first direction. A plurality of members constituting the overlapped end portion and a welded portion obtained by welding the end edges of the members adjacent to the first direction among the plurality of members are provided, and the welded portion is in the second direction. And when the end is viewed from the outside of the end along the first direction and the third direction intersecting the second direction, the end is spaced from both ends of the first direction. It is exposed after opening.

In the product, for example, the weld is in the first and second directions from the surface extending in the first and second directions of the end including the edge adjacent to the first direction. It has a weld metal extending in an intersecting third direction and a heat-affected zone located around the weld metal, and the width of the weld metal in the first direction at a depth in the third direction. The aspect ratio with respect to is 1 or more and 5 or less.

In the product, for example, the aspect ratio is 1.5 or more and 5 or less.

According to the present invention, for example, a new improved welding method and welding device capable of welding a plurality of overlapping members, and a product welded by the welding method or the welding device are obtained. be able to.

FIG. 1 is an exemplary schematic configuration diagram of the laser welding apparatus of the first embodiment. FIG. 2 is a schematic side view showing an example of a holding mechanism for a processing target included in the laser welding apparatus of the first embodiment. FIG. 3 is a schematic plan view showing an example of a holding mechanism for a processing target included in the laser welding apparatus of the first embodiment. FIG. 4 is an exemplary schematic diagram showing a beam (spot) of laser light formed on the surface of a processing target by the laser welding apparatus of the first embodiment. FIG. 5 is a graph showing the light absorption rate of each metal material with respect to the wavelength of the irradiated laser light. FIG. 6 is an exemplary and schematic cross-sectional view of the welded portion of the embodiment. FIG. 7 is an exemplary and schematic cross-sectional view showing a portion of the welded portion of the embodiment. FIG. 8 is a schematic side view showing an example of a holding mechanism for a processing target included in the laser welding apparatus of the first embodiment. FIG. 9 is an exemplary schematic configuration diagram of the laser welding apparatus of the second embodiment. FIG. 10 is an explanatory diagram showing the concept of the principle of the diffractive optical element included in the laser welding apparatus of the second embodiment. FIG. 11 is an exemplary schematic configuration diagram of the laser welding apparatus of the third embodiment. FIG. 12 is an exemplary schematic configuration diagram of the laser welding apparatus of the fourth embodiment. FIG. 13 is an exemplary schematic configuration diagram of the laser welding apparatus of the fifth embodiment. FIG. 14 is a schematic view showing an example of a beam (spot) of laser light formed on the surface of a processing target by the laser welding apparatus of the fifth embodiment. FIG. 15 is a schematic diagram showing an example of a beam (spot) of laser light formed on the surface of a processing target by the laser welding apparatus of the fifth embodiment. FIG. 16 is an exemplary and schematic perspective view of the product of the sixth embodiment. FIG. 17 is a cross-sectional view taken along the line XVII-XVII of FIG. FIG. 18 is an exemplary and schematic cross-sectional view of the product of the first modification of the sixth embodiment. FIG. 19 is an exemplary and schematic cross-sectional view of the product of the second modification of the sixth embodiment. FIG. 20 is an exemplary and schematic cross-sectional view of the product of the third modification of the sixth embodiment. FIG. 21 is an exemplary and schematic exploded perspective view of the product of the fourth modification of the sixth embodiment. FIG. 22 is an exemplary and schematic cross-sectional view of the product of the fourth modification of the sixth embodiment. FIG. 23 is an exemplary schematic configuration diagram of the laser welding apparatus of the seventh embodiment.

Hereinafter, exemplary embodiments and variations of the present invention will be disclosed. The configurations of the embodiments and modifications shown below, as well as the actions and results (effects) brought about by the configurations, are examples. The present invention can also be realized by configurations other than those disclosed in the following embodiments and modifications. Further, according to the present invention, it is possible to obtain at least one of various effects (including derivative effects) obtained by the configuration.

The embodiments and modifications shown below have similar configurations. Therefore, according to the configurations of the respective embodiments and modifications, the same actions and effects based on the similar configurations can be obtained. Further, in the following, the same reference numerals are given to those similar configurations, and duplicate explanations may be omitted.

Further, in each figure, the X direction is represented by an arrow X, the Y direction is represented by an arrow Y, and the Z direction is represented by an arrow Z. The X, Y, and Z directions intersect and are orthogonal to each other. The X direction is the sweep direction SD, and is also the extension direction (longitudinal direction) of the welded portion 14. The Y direction is the stacking direction and is also the width direction (short direction) of the welded portion 14. The Z direction is the normal direction of the surface Wa (machined surface, welded surface) of the machined object (welded object).

Further, in the present specification, the ordinal number is given for convenience in order to distinguish parts, members, parts, laser beams, directions, etc., and does not indicate a priority or an order.

[First Embodiment]
FIG. 1 is a schematic configuration diagram of the laser welding apparatus 100 of the first embodiment. As shown in FIG. 1, the laser welding apparatus 100 includes a laser apparatus 111, a laser apparatus 112, an optical head 120, and an optical fiber 130. The laser welding device 100 is an example of a welding device.

Each of the laser devices 111 and 112 has a laser oscillator, and is configured to be capable of outputting, for example, a laser beam having a power of several kW. The laser devices 111 and 112 emit laser light having a wavelength of 380 [nm] or more and 1200 [nm] or less. The laser devices 111 and 112 have a laser light source such as a fiber laser, a semiconductor laser (element), a YAG laser, and a disk laser inside. The laser devices 111 and 112 may be configured to be capable of outputting multimode laser light having a power of several kW as the total of the outputs of the plurality of light sources.

The laser apparatus 111 outputs the first laser beam having a wavelength of 800 [nm] or more and 1200 [nm] or less. The laser device 111 is an example of the first laser device. As an example, the laser device 111 has a fiber laser or a semiconductor laser (element) as a laser light source. The laser oscillator included in the laser device 111 is an example of the first laser oscillator.

On the other hand, the laser device 112 outputs a second laser beam having a wavelength of 500 [nm] or less. The laser device 112 is an example of a second laser device. As an example, the laser device 112 has a semiconductor laser (element) as a laser light source. The laser device 112 preferably outputs a second laser beam having a wavelength of 400 [nm] or more and 500 [nm] or less. The laser oscillator included in the laser device 112 is an example of a second laser oscillator.

The optical fiber 130 guides the laser light output from the laser devices 111 and 112 to the optical head 120, respectively.

The optical head 120 is an optical device for irradiating the laser beam input from the laser devices 111 and 112 toward the processing target. The optical head 120 includes a collimating lens 121, a condenser lens 122, a mirror 123, and a filter 124. The collimating lens 121, the condenser lens 122, the mirror 123, and the filter 124 may also be referred to as optical components.

The optical head 120 is configured to be able to change its relative position to the processing target in order to sweep the laser light L while irradiating the surface Wa of the end portion 10a as the processing target with the laser light L. Relative movement between the optical head 120 and the processing target can be realized by moving the optical head 120, moving the processing target, or moving both the optical head 120 and the processing target.

The optical head 120 may be configured to be able to sweep the laser beam L on the surface Wa by having a galvano scanner or the like (not shown).

The collimating lenses 121 (121-1, 121-2) collimate the laser beam input via the optical fiber 130, respectively. The collimated laser beam becomes parallel light.

The mirror 123 reflects the first laser beam that has become parallel light by the collimating lens 121-1. The first laser beam reflected by the mirror 123 travels in the opposite direction to the Z direction and heads toward the filter 124. The mirror 123 is not required in the configuration in which the first laser beam is input to the optical head 120 so as to travel in the direction opposite to the Z direction.

The filter 124 is a high-pass filter that transmits the first laser beam and reflects the second laser beam without transmitting it. The first laser beam passes through the filter 124, travels in the opposite direction in the Z direction, and heads toward the condenser lens 122. On the other hand, the filter 124 reflects the second laser beam that has become parallel light by the collimated lens 121-2. The second laser beam reflected by the filter 124 travels in the opposite direction to the Z direction and heads toward the condenser lens 122.

The condenser lens 122 concentrates the first laser beam and the second laser beam as parallel light, and irradiates the processing target as the laser beam L (output light).

The processing target is a laminated body 10 in which the first member 11 and the second member 12 are stacked in the Y direction. The laminated body 10 has a first member 11, a second member 12, and a welded portion 14 to which the first member 11 and the second member 12 are welded. The laminated body 10 becomes a product by welding the first member 11 and the second member 12 by the welded portion 14. The first member 11 and the second member 12 each have a plate-like shape that extends in the Y direction. The portions welded by the welded portions 14 of the first member 11 and the second member 12 extend in the X direction and the Z direction, respectively. The first member 11 and the second member 12 can also be referred to as plate-shaped members, respectively. The Y direction is an example of the first direction. The first member 11 and the second member 12 are examples of a plurality of members.

The end portion 10a of the laminated body 10 has edge edges 11a and 12a. The edge 11a includes the edge 11a of the first member 11 and the edge 12a of the second member 12. The edge edges 11a and 12a each extend in the X direction. The edge edges 11a and 12a may also be referred to as end faces. The edge edges 11a and 12a are arranged in the Y direction. The edges 11a and 12a are substantially flush with each other, but may have some steps. The edges 11a, 12a form the surface Wa of the end 10a facing the optical head 120. The X direction is an example of the second direction.

The laser beam L is irradiated from the outside of the end portion 10a toward the boundary between the edge 11a and the edge 12a in the opposite direction in the Z direction. As a result, the end portion 10a is formed with a welded portion 14 extending from the surface Wa along the boundary in the opposite direction in the Z direction. That is, the welded portion 14 joins the edge 11a and the edge 12a. Further, the welded portion 14 extends linearly in the sweep direction SD (X direction) along the surface Wa due to the sweep of the laser beam L with respect to the surface Wa in the sweep direction SD. The Z direction is an example of the third direction.

FIG. 2 is a side view of the holding mechanism 150 of the laminated body 10, and FIG. 3 is a plan view of the holding mechanism 150. As shown in FIGS. 2 and 3, the holding mechanism 150 includes a pressing member 151 and supporting members 152 and 153.

The pressing member 151 is, for example, a plate-shaped member that spreads across the Z direction, and is made of, for example, a metal material having relatively high thermal conductivity. The two pressing members 151 are arranged so as to sandwich the laminated body 10 in the Y direction. Further, the support members 152 and 153 are arranged so as to sandwich the pressing member 151 in the Z direction, and hold the pressing member 151. The support members 152 and 153 are such that the two pressing members 151 apply a force to the laminated body 10 so that the first member 11 and the second member 12 approach each other in the Y direction from both sides in the Y direction. Holds 151. That is, by adjusting the positions of the pressing member 151 and the supporting members 152 and 153 in the holding mechanism 150, the laminated body 10 can be set in an appropriate position and posture with respect to the laser beam L.

Further, as shown in FIG. 2, in the present embodiment, the welded portion 14 is viewed in the direction opposite to the Z direction, that is, when the laminated body 10 is viewed from the outside of the end portion 10a along the Z direction. , The ends 10a are exposed at intervals from the ends 10a1 on both sides in the Y direction, and do not reach both end faces of the laminated body 10 in the Y direction.

FIG. 4 is a schematic diagram showing a beam (spot) of the laser beam L irradiated on the surface Wa. Each of the beam B1 and the beam B2 has a Gaussian-shaped power distribution in the radial direction of the cross section orthogonal to the optical axis direction of the beam. However, the power distribution of the beam B1 and the beam B2 is not limited to the Gaussian shape. Further, in each figure in which each beam B1 and B2 is represented by a circle as shown in FIG. 4, the diameter of the circle representing the beams B1 and B2 is the beam diameter of each beam B1 and B2. Beam diameter of each beam B1, B2 includes a peak of the beam is defined as the diameter of the region of 1 / e ² or more of the intensity of the peak intensity. Although not shown, in the case of a non-circular beam, ^{the length of a region having an intensity of 1 / e 2} or more of the peak intensity in the direction perpendicular to the sweep direction SD can be defined as the beam diameter. Further, the beam diameter on the surface Wa is referred to as a spot diameter.

As shown in FIG. 4, in the present embodiment, as an example, in the beam of the laser beam L, the beam B1 of the first laser beam and the beam B2 of the second laser beam overlap on the surface Wa, and the beam B2 is formed. It is larger (wider) than the beam B1 and is formed so that the outer edge B2a of the beam B2 surrounds the outer edge B1a of the beam B1. In this case, the spot diameter D2 of the beam B2 is larger than the spot diameter D1 of the beam B1. On the surface Wa, the beam B1 is an example of the first spot, and the beam B2 is an example of the second spot.

Further, in the present embodiment, as shown in FIG. 4, since the beam (spot) of the laser beam L has a point-symmetrical shape with respect to the center point C on the surface Wa, the SD in an arbitrary sweep direction is used. , The shape of the spot will be the same. Therefore, when a moving mechanism for relatively moving the optical head 120 and the processing target for sweeping the surface Wa of the laser beam L is provided, the moving mechanism should have at least a relatively translatable mechanism. Often, relatively rotatable mechanisms may be omitted.

When there is a gap (not shown) in which the end edges 11a and 12a are slightly separated from each other in the Y direction at the boundary Br between the first member 11 and the second member 12, the laser beam L so as to straddle the gap. Be irradiated. As an example, the laser welding apparatus 100 and the laminated body 10 are set so that the beam B2 of the second laser beam straddles the gap in the Y direction on the surface Wa. In this case, the width of the spot of the second laser beam (for example, the spot diameter D2 in FIG. 4) becomes larger than the width of the gap.

The first member 11 and the second member 12 to be processed can be made of a metal material having a relatively high thermal conductivity, respectively. The metal material is, for example, a copper-based metal material, an aluminum-based metal material, a nickel-based metal material, an iron-based metal material, a titanium-based metal material, or the like, and specifically, copper, a copper alloy, aluminum, or an aluminum alloy. , Tin, nickel, nickel alloy, iron, stainless steel, titanium, titanium alloy, etc. The first member 11 and the second member 12 may be made of the same material or may be made of different materials.

[Wavelength and light absorption rate]
Here, the light absorption rate of the metal material will be described. FIG. 5 is a graph showing the light absorption rate of each metal material with respect to the wavelength of the laser beam L to be irradiated. The horizontal axis of the graph of FIG. 5 is the wavelength, and the vertical axis is the absorption rate. FIG. 5 shows the relationship between wavelength and absorption for aluminum (Al), copper (Cu), gold (Au), nickel (Ni), silver (Ag), tantalum (Ta), and titanium (Ti). It is shown.

Although the characteristics differ depending on the material, for each metal shown in FIG. 5, a blue or green laser beam (second laser) is used rather than using a general infrared (IR) laser beam (first laser beam). It can be understood that the energy absorption rate is higher when light) is used. This feature is remarkable in copper (Cu), gold (Au), and the like.

When a laser beam is applied to a processing target having a relatively low absorption rate with respect to the wavelength used, most of the light energy is reflected and does not affect the processing target as heat. Therefore, it is necessary to apply a relatively high power in order to obtain a melting region having a sufficient depth. In that case, energy is suddenly applied to the central part of the beam, so that sublimation occurs and a keyhole is formed.

On the other hand, when the laser beam is applied to a processing target having a relatively high absorption rate with respect to the wavelength used, most of the input energy is absorbed by the processing target and converted into thermal energy. That is, since it is not necessary to apply excessive power, heat conduction type melting is performed without forming keyholes.

In the present embodiment, the wavelength of the first laser beam, the wavelength of the second laser beam, and the material to be processed are set so that the absorption rate for the second laser beam to be processed is higher than the absorption rate for the first laser beam. , Is selected. In this case, when the sweep direction is the sweep direction SD shown in FIG. 5, the welded portion (hereinafter referred to as the welded portion) to be processed by the spot of the laser beam L is first subjected to the second. The second laser beam is irradiated by the region B2f of the laser beam B2 located in front of the SD in FIG. After that, the welded portion is irradiated with the beam B1 of the first laser beam, and then the second laser beam is irradiated again by the region B2b of the beam B2 of the second laser beam located behind the sweep direction SD. To.

Therefore, in the welded portion, a heat conduction type melting region is first generated by irradiation with a second laser beam having a high absorption rate in the region B2f. After that, a deeper keyhole-type melting region is generated in the welded portion by irradiation with the first laser beam. In this case, since the heat conduction type melting region is formed in advance in the welded portion, the required depth is obtained by the first laser beam having a lower power than in the case where the heat conduction type melting region is not formed. A molten region can be formed. After that, the welded portion is changed in a molten state by irradiation with a second laser beam having a high absorption rate in the region B2b.

Further, experimental studies by the inventors have confirmed that welding defects such as spatters and blowholes can be reduced in welding by irradiation with a laser beam L as shown in FIG. This is because the molten pool of the processing target formed by the beam B2 and the beam B1 is more stabilized by preheating the processing target by the region B2f of the beam B2 before the arrival of the beam B1. Can be estimated.

[Welding method]
In welding using the laser welding apparatus 100, first, the laminated body 10 is set in the holding mechanism 150 so that the laser beam L is irradiated on the surface Wa. Then, in a state where the surface Wa is irradiated with the laser beam L including the beam B1 and the beam B2, the laser beam L and the laminated body 10 (holding mechanism 150) are relatively moved. As a result, the laser beam L moves (sweeps) in the sweep direction SD on the surface Wa while being irradiated on the surface Wa. The portion irradiated with the laser beam L melts, and then solidifies as the temperature decreases, so that the first member 11 and the second member 12 are welded together, and the laminated body 10 is integrated.

[Cross section of weld]
FIG. 6 is a cross-sectional view of a welded portion 14 formed on the processing target W. FIG. 6 is a cross-sectional view perpendicular to the sweep direction SD (X direction) and along the thickness direction (Z direction). The welded portion 14 extends in the sweep direction SD, that is, in the direction perpendicular to the paper surface of FIG. Note that FIG. 6 shows a cross section of the welded portion 14 formed on the processing target W, which is a single copper plate having a thickness of 2 [mm]. The form of the welded portion 14 formed of a plurality of plate-shaped metal materials stacked in the Y direction is the same as the form of the welded portion 14 formed on the processing target W which is one metal material shown in FIG. It can be estimated that they are almost equivalent.

As shown in FIG. 6, the welded portion 14 has a welded metal 14a extending in the opposite direction in the Z direction from the surface Wa, and a heat-affected zone 14b located around the welded metal 14a. .. The weld metal 14a is a portion that is melted by irradiation with the laser beam L and then solidified. The weld metal 14a may also be referred to as a melt-solidified portion. Further, the heat-affected zone 14b is a portion where the base material to be processed is heat-affected and is not melted.

The width of the weld metal 14a along the Y direction becomes narrower as the distance from the surface Wa increases. That is, the cross section of the weld metal 14a has a tapered shape that narrows in the direction opposite to the Z direction.

Further, according to a detailed analysis of the cross section by the inventors, the weld metal 14a includes a first portion 14a1 away from the surface Wa and a second portion 14a2 between the first portion 14a1 and the surface Wa. There was found.

The first portion 14a1 is a region obtained by keyhole-type melting by irradiation with the first laser beam, and the second portion 14a2 is a region located behind the sweep direction SD in the beam B2 of the second laser beam. It is a part obtained by melting by irradiation of B2b. According to the analysis by the EBSD method (electron back scattered diffraction pattern), the size of the crystal grains is different between the first site 14a1 and the second site 14a2, and specifically, the X direction (sweep direction). It was found that the average cross-sectional area of the crystal grains at the second site 14a2 was larger than the average cross-sectional area of the crystal grains at the first site 14a1 in the cross section orthogonal to SD).

The inventors have found that when the processing target W is irradiated with only the beam B1 of the first laser beam, that is, when the region B2b located behind the sweep direction SD in the beam B2 is not irradiated, the second It was confirmed that the site 14a2 was not formed and the first site 14a1 extended deeply from the surface Wa in the opposite direction to the Z direction. That is, in the present embodiment, the second portion 14a2 is formed near the surface Wa by the irradiation of the region B2b located behind the sweep direction SD in the beam B2, so that the first portion 14a1 is the said. It can be presumed that the second portion 14a2 is formed on the opposite side of the surface Wa, in other words, at a position separated from the surface Wa in the opposite direction in the Z direction.

FIG. 7 is a cross-sectional view showing a part of the welded portion 14. FIG. 7 shows the boundaries of the crystal grains obtained by the EBSD method. Further, in FIG. 7, as an example, the crystal grain A having a crystal grain size of 13 [μm] or less is painted black. Note that 13 [μm] is not a threshold value of physical characteristics, but a threshold value set for analysis of the experimental results. Further, from FIG. 7, it is clear that the crystal grains A are relatively abundant in the first site 14a1 and relatively few in the second site 14a2. That is, the average value of the cross-sectional areas of the crystal grains in the second site 14a2 is larger than the average value of the cross-sectional areas of the crystal grains in the first site 14a1. According to an experimental analysis, the inventors have found that the average cross-sectional area of the crystal grains in the second site 14a2 is 1.8 times or more the average cross-sectional area of the crystal grains in the first site 14a1. It was confirmed.

As shown in the region I in FIG. 7, such relatively small crystal grains A are densely packed in a position separated from the surface Wa in the Z direction and elongated in the Z direction. There is. Further, from the analysis at a plurality of locations where the positions in the X direction (sweep direction SD) are different, it is confirmed that the region where the crystal grains A are densely extends extends to the sweep direction SD. Since the welding is performed while sweeping, it can be presumed that crystals are formed in the same shape in the sweep direction SD.

When it is difficult to distinguish between the first portion 14a1 and the second portion 14a2 from the appearance or hardness distribution in the cross section, geometry is performed from the position and width wb of the weld metal 14a on the surface Wa as shown in FIGS. The geographically determined first region Z1 and second region Z2 may be designated as the first region 14a1 and the second region 14a2, respectively. As an example, the first region Z1 and the second region Z2 are rectangular regions extending in the Z direction with a width wm (equal width in the Y direction) in a cross section orthogonal to the sweep direction SD, and the second region Z2. Is a region from the surface Wa to the depth d in the Z direction, and the first region Z1 is a region deeper than the depth d, in other words, a region opposite to the surface Wa with respect to the position of the depth d. can do. The width wm is, for example, 1/3 of the width wb (average value of the bead width) on the surface Wa of the weld metal 14a, and the depth d (height, thickness) of the second region Z2 is, for example, the width wb. Can be 1/2 of. Further, the depth of the first region Z1 can be, for example, three times the depth d of the second region Z2. The inventors have conducted experimental analysis on a plurality of samples, and in such a setting of the first region Z1 and the second region Z2, the average value of the cross-sectional areas of the crystal grains in the second region Z2 is in the first region Z1. It was confirmed that it was larger than the average value of the cross-sectional area of the crystal grains and was 1.8 times or more. Such discrimination can also be evidence that the first portion 14a1 and the second portion 14a2 are formed in the weld metal 14a by welding.

Further, according to the experimental research by the inventors, the aspect ratio of the weld metal 14a, that is, the ratio of the depth dm to the width wb on the surface Wa of the weld metal 14a (dm / wb) is determined to ensure the welding strength and the welding width. From the viewpoint of suppressing the above, it was found that 1 or more and 5 or less is preferable, and 1.5 or more and 5 or less is more preferable.

As described above, in the present embodiment, for example, the laser beam L emitted from the laser devices 111, 112 (laser oscillator) including the fiber laser is emitted from the outside of the end portion 10a along the Z direction (in the Z direction). By irradiating (in the opposite direction), the edge edges 11a and 12a adjacent to the Y direction (first direction) are welded. The wavelength of the laser beam L is 380 [nm] or more and 1200 [nm] or less.

According to such a configuration and method, for example, it is easy to obtain a welded portion 14 having a relatively large welding depth with respect to a welding width and a required welding strength. In addition, air entrainment inside the molten metal during welding is suppressed, and welding defects can be reduced.

Further, in the present embodiment, the laser beam L includes, for example, a first laser beam having a wavelength of 800 [nm] or more and 1200 [nm] or less, and a second laser beam having a wavelength of 500 [nm] or less. I'm out.

Further, in the present embodiment, for example, the wavelength of the second laser beam is 400 [nm] or more and 500 [nm] or less.

According to such a configuration and method, it is easy to obtain a higher quality welded portion 14 having less welding defects such as spatters and blow holes.

Further, in the present embodiment, for example, when a gap is provided at the boundary Br between the edge edges 11a and 12a, the second laser beam is irradiated on the surface Wa so as to straddle the gap.

According to such a configuration and method, for example, irradiation with a second laser beam having a relatively high absorptance in a metal material produces heat-conducting molten regions at the edges 11a and 12a on both sides of the gap, so that the welded portion is formed. With 14, the gap can be filled more reliably, and by extension, a welded portion 14 having higher joint strength can be easily obtained.

Further, in the present embodiment, for example, on the surface Wa, at least a part of the beam B2 (second spot) of the second laser beam has a sweep direction SD more than the beam B1 (first spot) of the first laser beam. It is located in front.

Further, in the present embodiment, for example, the beam B1 and the beam B2 partially overlap each other on the surface Wa.

Further, in the present embodiment, for example, on the surface Wa, the beam B2 is wider than the beam B1.

Further, in the present embodiment, for example, on the surface Wa, the outer edge B2a (second outer edge) of the beam B2 surrounds the outer edge B1a (first outer edge) of the beam B1.

As described above, the inventors have confirmed that welding defects can be reduced in welding by irradiation with a beam of laser light L forming such beams B1 and B2 on the surface Wa. This is because, as described above, the processing target W is preheated by the region B2f of the beam B2 before the beam B1 arrives, so that the molten pool of the processing target W formed by the beam B2 and the beam B1 is further formed. It can be presumed that this is for stabilization. Therefore, according to the laser beam L having such beams B1 and B2, for example, welding with less welding defects and higher welding quality can be performed. Further, according to such settings of the beams B1 and B2, there is an advantage that, for example, the power of the first laser beam can be further lowered. Further, when the beam B1 and the beam B2 are irradiated coaxially, there is an advantage that the relative rotation between the optical head 120 and the processing target W becomes unnecessary.

Further, in the present embodiment, for example, the aspect ratio of the weld metal 14a is preferably 1 or more and 5 or less, and more preferably 1.5 or more and 5 or less.

According to such a configuration, for example, it is easy to obtain the required welding strength, and it is possible to prevent the welding width from becoming too large.

Further, in the present embodiment, for example, the processing target is made of any one of a copper-based metal material, an aluminum-based metal material, a nickel-based metal material, an iron-based metal material, and a titanium-based metal material.

The effect of the welding method of the present embodiment is obtained when the processing target is made of any of the above materials. The metal material may or may not have conductivity.

[Modification example of holding mechanism]
FIG. 8 is a side view showing another example of the holding mechanism 150A. The holding mechanism 150A may be equipped in place of the holding mechanism 150 of the first embodiment. The holding mechanism 150A includes a pressing member 151A, a base 154, and a support member 155. The two pressing members 151A are arranged so as to sandwich the laminated body 10 in the Y direction. Each of the two support members 155 supports the pressing member 151A so as to be rotatable around the rotation axis Ax along the Y direction. Further, the two support members 155 are arranged on both sides in the Y direction with respect to the laminated body 10, and are respectively mounted on the base 154 so that the positions in the Y direction can be changed. Then, the two support members 155 apply a force from the two pressing members 151 to the laminated body 10 so that the first member 11 and the second member 12 approach each other in the Y direction from both sides in the Y direction to the base 154. It is fixed. That is, by adjusting the position of the support member 155 in the holding mechanism 150A, the laminated body 10 can be set in an appropriate position and posture with respect to the laser beam L. Further, by rotating the pressing member 151A and the laminated body 10 with respect to the support member 155 around the rotation axis Ax, the laser beam L can be swept from the surface Wa of the end portion 10a.

[Second Embodiment]
FIG. 9 is a schematic configuration diagram of the laser welding apparatus 100A of the second embodiment. In this embodiment, the optical head 120 has a DOE 125 between the collimating lens 121-1 and the mirror 123. Except for this point, the laser welding apparatus 100A has the same configuration as the laser welding apparatus 100 of the first embodiment.

The DOE125 forms the shape of the beam B1 of the first laser beam (hereinafter referred to as the beam shape). As conceptually illustrated in FIG. 10, the DOE 125 has, for example, a configuration in which a plurality of diffraction gratings 125a having different periods are superposed. The DOE 125 can form a beam shape by bending or superimposing parallel light in a direction affected by each diffraction grating 125a. DOE125 may also be referred to as a beam shaper.

The optical head 120 has a beam shaper provided after the collimating lens 121-2 to adjust the beam shape of the second laser beam, and a beam shaper provided after the filter 124 to adjust the beam shapes of the first laser beam and the second laser beam. It may have a beam shaper or the like to be adjusted. By appropriately adjusting the beam shape of the laser beam L by the beam shaper, the occurrence of welding defects can be further suppressed.

Further, in the configuration of FIG. 9, the DOE 125 can generate a beam having the same beam shape as that of the second laser beam, whereby the laser device 112 can be omitted. In this case as well, it is possible to suppress the generation of spatter in welding.

[Third Embodiment]
FIG. 11 is a schematic configuration diagram of the laser welding apparatus 100B of the third embodiment. In this embodiment, the optical head 120 has a galvano scanner 126 between the filter 124 and the condenser lens 122. Except for this point, the laser welding apparatus 100B has the same configuration as the laser welding apparatus 100 of the first embodiment.

The galvano scanner 126 has two mirrors 126a and 126b, and by controlling the angles of the two mirrors 126a and 126b, the irradiation position of the laser beam L can be set without moving the optical head 120. It is a device that can be moved to sweep the laser beam L. The angles of the mirrors 126a and 126b are changed by, for example, a motor (not shown). With such a configuration, a mechanism for relatively moving the optical head 120 and the processing target becomes unnecessary, and for example, there is an advantage that the device configuration can be miniaturized.

[Fourth Embodiment]
FIG. 12 is a schematic configuration diagram of the laser welding apparatus 100C of the fourth embodiment. In this embodiment, the optical head 120 has a DOE125 (beam shaper) between the collimating lens 121-2 and the filter 124. Except for this point, the laser welding apparatus 100C has the same configuration as the laser welding apparatus 100B of the third embodiment. According to such a configuration, the same effect as the third embodiment by having the galvano scanner 126 and the same effect as the second embodiment by having the DOE125 (beam shaper) can be obtained.

Also in this embodiment, the optical head 120 is provided after the collimating lens 121-1 and is provided after the beam shaper for adjusting the beam shape of the first laser beam, and is provided after the filter 124 and is provided with the first laser beam and the second laser beam. It may have a beam shaper or the like that adjusts the beam shape of the laser beam.

[Fifth Embodiment]
FIG. 13 is a schematic configuration diagram of the laser welding apparatus 100D of the fifth embodiment. In the present embodiment, the optical head 120 has a first portion 120-1 for irradiating the first laser beam L1 and a second portion 120 for irradiating the second laser beam L2, which are configured by different bodies (housings). -2 and are provided. Even with such a configuration, the same operations and effects as those of the above embodiment can be obtained.

14 and 15 show examples of laser beam beams B1 and B2 formed on the surface Wa by the laser welding apparatus 100D. As shown in FIGS. 14 and 15, according to the laser welding apparatus 100D, the relative positions of the beams B1 and B2 are set by setting the relative positions and postures of the first portion 120-1 and the second portion 120-2. It can be set arbitrarily. According to the research by the inventors, at least a part of the beam B2 (second spot) is located in front of the beam B1 (first spot) in the sweep direction SD on the surface Wa as shown in FIGS. It has been found that the same effect as in the first embodiment due to the preheating effect of the beam B2 can be obtained when the beam B1 and the beam B2 are in contact with each other or at least partially overlap each other. It has also been found that when at least a part of the beam B2 is located in front of the beam B1 in the sweep direction SD, the beam B1 and the beam B2 may be separated by a minute distance. .. It should be noted that FIGS. 14 and 15 are merely examples, and the arrangement of the beams B1 and B2 obtained by the laser welding apparatus 100D and the sizes of the beams B1 and B2 are not limited to the examples of FIGS. 14 and 15.

[Sixth Embodiment]
16 is a perspective view of the vapor chamber 10E of the sixth embodiment, and FIG. 17 is a sectional view taken along the line XVII-XVII of FIG. As shown in FIG. 16, the vapor chamber 10E includes a flat rectangular and plate-shaped first member 11 and a second member 12. The first member 11 and the second member 12 are made of a metal material having a relatively high thermal conductivity. Further, the first member 11 and the second member 12 overlap each other in the Y direction. In the vapor chamber 10E, the edge portions 11a and 12a are welded all around by the welded portion 14 at the end portion 10a as the peripheral edge portion of the first member 11 and the second member 12 overlapping in the Y direction. The vapor chamber 10E is an example of a product.

As shown in FIG. 17, a storage chamber 10b for the fluid medium F is provided between the first member 11 and the second member 12. The storage chamber 10b is formed, for example, by providing the second member 12 with a bottomed recess that opens toward the first member 11. The recess may also be referred to as an opening. The containment chamber 10b is an example of a space.

The vapor chamber 10E is provided over a high temperature portion and a low temperature portion. The high temperature part is, for example, a heating element such as a CPU (central processing unit), and the low temperature part is a heat dissipation body such as a heat sink. The fluid medium F changes from a liquid phase to a gas phase by receiving heat from a high temperature portion, and changes from a gas phase to a liquid phase by dissipating heat to a low temperature portion. The fluid medium F, which has become a gas in the region adjacent to the high temperature portion in the accommodation chamber 10b, moves in the accommodation chamber 10b to the region adjacent to the low temperature portion in the accommodation chamber 10b in the state of the gas. Further, the fluid medium F that has become liquid in the region adjacent to the low temperature portion in the accommodation chamber 10b moves in the accommodation chamber 10b to the region adjacent to the high temperature portion in the accommodation chamber 10b due to the capillary phenomenon. Due to such heat transfer by the fluid medium F, the vapor chamber 10E can function as a cooling mechanism for the high temperature portion.

As shown in FIG. 17, the edge 11a and the edge 12a are joined by the welded portion 14. The welded portion 14 can be formed by the welding method and the laser welding apparatus 100, 100A to 100D shown in the above-described embodiments and modifications. The welded portion 14 has the same configuration as the welded portion 14 of the first embodiment. The fluid medium F is sealed in the accommodation chamber 10b by welding the end portion 10a as the peripheral edge portion of the first member 11 and the second member 12 all around by the welded portion 14.

According to the above embodiment, the same effect as that of the above embodiment can be obtained. That is, according to the vapor chamber 10E of the present embodiment, for example, a welded portion 14 having a relatively large welding depth with respect to a welded width and having a higher welding strength, and a higher quality welded portion 14 having fewer welding defects are provided. Easy to obtain.

[Variation example of the sixth embodiment]
18 to 22 show the vapor chambers 10F to 10I of the modified example of the sixth embodiment. In the vapor chamber 10F of the first modification shown in FIG. 18, the edge 11a of the flange 11b of the first member 11 and the edge 12a of the second member 12 are welded by the welded portion 14. Also in this vapor chamber 10F, the fluid medium F is sealed in the accommodating chamber 10b by welding the end portions 10a as peripheral edges of the first member 11 and the second member 12 all around by the welded portion 14. In this modification, the recess forming the accommodation chamber 10b is provided only in the first member 11.

In the vapor chamber 10G of the second modification shown in FIG. 19, the edge 11a as the outer peripheral surface of the first member 11 and the edge 12a of the second member 12 are welded by the welded portion 14. Also in this vapor chamber 10G, the fluid medium F is sealed in the accommodating chamber 10b by welding the end portion 10a as the peripheral edge portion of the first member 11 and the second member 12 all around by the welded portion 14. Also in this modification, the recess forming the accommodation chamber 10b is provided only in the first member 11.

In the vapor chamber 10H of the third modification shown in FIG. 20, the edge 11a as the outer peripheral surface of the first member 11 and the edge 12a as the outer peripheral surface of the second member 12 are welded by the welded portion 14. .. Also in this vapor chamber 10H, the fluid medium F is sealed in the accommodation chamber 10b by welding the end portion 10a as the peripheral edge portion of the first member 11 and the second member 12 all around by the welded portion 14. In this modification, the recesses forming the accommodation chamber 10b are provided in both the first member 11 and the second member 12.

FIG. 21 is an exploded perspective view of the vapor chamber 10I of the fourth modification, and FIG. 22 is a cross-sectional view taken along the Y direction through the substantially center of the vapor chamber 10I. In this modification, the third member 13 is interposed between the first member 11 and the second member 12. The third member 13 is a flat rectangular and plate-shaped member, and is made of a metal material having relatively high thermal conductivity. Further, the third member 13 overlaps with the first member 11 and the second member 12 in the Y direction. The third member 13 is provided with a plurality of slits 13b as through holes penetrating in the Y direction (stacking direction). Since both sides of each slit 13b in the Y direction are closed by the first member 11 and the second member 12, the accommodation chamber 10b of the fluid medium F is formed in the vapor chamber 10I. The through hole is an example of an opening. In addition, instead of the slit 13b, a recess that does not open the third member 13 may be provided, or the slit 13b (through hole) may be one.

In the vapor chamber 10I, the edge portions 11a and 13a are welded all around by the welded portion 14 at the end portion 10a as the peripheral edge portion of the first member 11 and the third member 13 overlapping in the Y direction. Further, at the end portion 10a as the peripheral edge portion of the second member 12 and the third member 13 overlapping in the Y direction, the edge portions 12a and 13a are welded all around by the welded portion 14. The third member 13 is one of a plurality of members. Even in the vapor chamber 10I of this modification, the fluid medium F is sealed in the accommodating chamber 10b by all-around welding by the welded portion 14. The same effect as that of the sixth embodiment can be obtained by the above-mentioned first to fourth modifications.

[7th Embodiment]
FIG. 23 is a schematic configuration diagram of the laser welding apparatus 100J of the fifth embodiment. The laser welding apparatus 100J of the present embodiment is modified based on the laser welding apparatus 100A of the second embodiment. The laser welding apparatus 100J includes a control unit 161, a camera 162, a drive mechanism 163, a mirror 164, and a filter 165 in addition to the components of the laser welding apparatus 100A.

The filter 165 is provided between the mirror 123 and the filter 124. The filter 165 transmits the first laser light from the mirror 123 toward the filter 124 and reflects the light from the surface Wa (for example, visible light) toward the mirror 164. The light reflected by the mirror 164 is input to the camera 162. With such a configuration, the camera 162 can capture an image on the surface Wa. The image captured by the camera 162 includes, for example, an image of the boundary of the edge 11a and 12a and an image of a beam (spot) by the laser beam L. That is, the image shows a deviation of the spot of the laser beam L formed on the surface Wa with respect to the position (predetermined position) of the boundary where the laser beam L should be originally irradiated. Therefore, the image captured by the camera 162 can be said to be the detection result of the deviation of the spot formed on the surface Wa with respect to a predetermined position, and the camera 162 can be said to be an example of the detection mechanism for detecting the deviation. can. When the position of the spot at the angle of view of the captured image is fixed, the captured image does not need to include the spot image, and the control unit 161 may use the edge 11a in the captured image. From the position of the image at the boundary of 12a, it is possible to detect the deviation of the spot formed on the surface Wa with respect to a predetermined position.

The control unit 161 detects a deviation of the spot with respect to a predetermined position from the image captured by the camera 162, and controls the drive mechanism 163 so as to correct the deviation. The drive mechanism 163 is an actuator that operates in response to a command (electrical signal) from the control unit 161 and can move the optical head 120 in a direction intersecting the Z direction, for example, in the Y direction. The drive mechanism 163 can have, for example, a rotation mechanism such as a motor, a deceleration mechanism for decelerating the rotation output of the rotation mechanism, a motion conversion mechanism for converting the rotation decelerated by the deceleration mechanism into linear motion, and the like. .. At this time, the control unit 161 may execute feedback control that executes control until the deviation is within a predetermined threshold value. The control unit 161 and the drive mechanism 163 are examples of the correction mechanism. With such a configuration, it is possible to reduce the positional deviation of the welded portion 14 with respect to a predetermined position, and by extension, it is possible to further increase the welding strength of the welded portion 14, which is an advantage.

When applied to the laser welding devices 100B and 100C having the galvano scanner 126 as in the third embodiment and the fourth embodiment, the control unit 161 changes the position of the optical head 120 by the drive mechanism 163. By changing the irradiation direction of the laser beam L, the position of the spot on the surface Wa may be changed. Similar actions and effects can be obtained with such a configuration. In this case, the control unit 161 and the galvano scanner 126 are examples of the correction mechanism.

Although the embodiments of the present invention have been exemplified above, the above-described embodiment is an example and is not intended to limit the scope of the invention. The above embodiment can be implemented in various other embodiments, and various omissions, replacements, combinations, and changes can be made without departing from the gist of the invention. In addition, specifications such as each configuration and shape (structure, type, direction, model, size, length, width, thickness, height, number, arrangement, position, material, etc.) are changed as appropriate. Can be carried out.

For example, the vapor chamber is an example of a product, and the product is not limited to the vapor chamber.

Further, when the laser beam is swept to the object to be processed, the surface area of the molten pool may be adjusted by sweeping by known wobbling, weaving, output modulation or the like.

Further, the processing target may be one in which another thin metal layer is present on the surface of the metal, such as a plated metal plate.

10 ... Laminated body (product)
10E-10I ... Vapor chamber (product)
10a ... end 10a1 ... end 10b ... accommodation room (space)
11 ... First member 11a ... Edge edge 11b ... Flange 12 ... Second member 12a ... Edge edge 13 ... Third member 13a ... Edge edge 13b ... Slit 14 ... Welded portion 14a ... Welded metal 14a1 ... First part 14a2 ... Second Part 14b ... Heat-affected zone 100, 100A-100D, 100J ... Laser welding equipment (welding equipment)
111 ... Laser device (first laser oscillator)
112 ... Laser device (second laser oscillator)
120 ... Optical head 120-1 ... First part 120-2 ... Second part 121, 121-1, 121-2 ... Collimating lens 122 ... Condensing lens 123 ... Mirror 124 ... Filter 125 ... DOE (diffractive optical element)
125a ... Diffraction grating 126 ... Galvano scanner (correction mechanism)
126a, 126b ... Mirror 130 ... Optical fiber 150, 150A ... Holding mechanism 151, 151A ... Pressing member 152, 153 ... Support member 154 ... Base 155 ... Support member 161 ... Control unit (correction mechanism)
162 ... Camera (detection mechanism)
163 ... Drive mechanism (correction mechanism)
164 ... Mirror 165 ... Filter A ... Crystal grain Ax ... Rotation axis B1 ... Beam (first spot)
B1a ... Outer edge B2 ... Beam (second spot)
B2a ... Outer edge B2b ... Region B2f ... Region Br ... Boundary C ... Center point D1 ... Spot diameter (outer diameter)
D2 ... Spot diameter (outer diameter)
d ... Depth dm ... Depth F (of weld metal) F ... Fluid medium I ... Region L ... Laser beam L1 ... First laser beam L2 ... Second laser beam SD ... Sweeping direction W ... Machining target Wa ... Surface wb ... ( Width wm (on the surface of the weld metal) ... Width X ... (second direction) (of the first and second regions)
Y ... direction (first direction, stacking direction)
Z ... direction (third direction)
Z1 ... First area (first part)
Z2 ... Second area (second part)

Claims (24)

The edges of the plurality of members overlapping in the first direction extending in the second direction intersecting with the first direction are aligned in the first direction, from the outside of the end to the first direction and the end. A welding method in which the edge edges adjacent to the first direction are welded to each other by irradiating a laser beam emitted from a laser oscillator including a fiber laser along a third direction intersecting the second direction. hand,
A welding method in which the wavelength of the laser beam is 380 [nm] or more and 1200 [nm] or less. The welding method according to claim 1, wherein the laser light includes a first laser light having a wavelength of 800 [nm] or more and 1200 [nm] or less, and a second laser light having a wavelength of 500 [nm] or less. .. The welding method according to claim 2, wherein the wavelength of the second laser beam is 400 [nm] or more and 500 [nm] or less. The welding method according to claim 2 or 3, wherein the second laser beam is irradiated so as to straddle the gap of the boundary between the edges adjacent to the first direction in the first direction. The laser beam is swept in a sweep direction along the second direction on the surface of the end extending in the first direction and the second direction.
On the surface, at least a part of the second spot formed on the surface by the second laser beam is in front of the first spot formed on the surface by the first laser beam in the sweep direction. The welding method according to any one of claims 2 to 4, which is located in. The welding method according to claim 5, wherein the first spot and the second spot overlap at least partially on the surface. The welding method according to claim 5, wherein the second outer edge of the second spot surrounds the first outer edge of the first spot on the surface. Each of the plurality of members is made of any one of a copper-based metal material, an aluminum-based metal material, a nickel-based metal material, an iron-based metal material, and a titanium-based metal material, claim 1 to 1. The welding method according to any one of 7. Laser oscillators including fiber lasers and
The edges of the plurality of members overlapping in the first direction extending in the second direction intersecting with the first direction are aligned in the first direction, from the outside of the end to the first direction and the end. An optical head that irradiates a laser beam emitted from the laser oscillator along a third direction intersecting the second direction.
A welding device that welds the edges adjacent to each other in the first direction.
A welding apparatus having a wavelength of the laser beam of 380 [nm] or more and 1200 [nm] or less. The welding apparatus according to claim 9, further comprising a beam shaper that divides the laser beam into a plurality of beams. A galvano scanner is provided that changes the emission direction of the laser beam so that the laser beam moves in a sweep direction along the second direction on the surface extending in the first direction and the second direction of the end portion. , The welding apparatus according to claim 9 or 10. The welding apparatus according to any one of claims 9 to 11, further comprising a rotation mechanism for rotating the end portion around a rotation axis along the first direction. A detection mechanism that detects deviations of spots formed on the surface by the laser beam from a predetermined position, and
A correction mechanism that corrects the deviation and
The welding apparatus according to any one of claims 9 to 12, comprising the above. A plurality of members each having an edge extending in the second direction and overlapping in the first direction with each edge aligned in the first direction intersecting with the second direction.
A welded portion obtained by welding the edges of the members adjacent to each other in the first direction among the plurality of members.
Equipped with
The welded part is
A weld metal extending in a third direction intersecting the first direction and the second direction from the surface extending in the first direction and the second direction of the end including the edge adjacent to the first direction. When,
The heat-affected zone located around the weld metal and
Have,
The weld metal is a product having a first portion and a second portion having a larger average cross-sectional area of crystal grains in a cross section intersecting the second direction than the first portion. The product according to claim 14, wherein the average value of the cross-sectional areas of the crystal grains contained in the second portion is 1.8 times or more the average value of the cross-sectional areas of the crystal grains contained in the first portion. The product according to claim 14 or 15, wherein the weld metal extends in the second direction. The product according to any one of claims 14 to 16, wherein the weld metal has an aspect ratio of the depth in the third direction to the width in the first direction of 1 or more and 5 or less. The product according to claim 17, wherein the aspect ratio is 1.5 or more and 5 or less. The first member and
A second member joined to the first member with a space formed between the first member and the second member.
Equipped with
The product according to any one of claims 14 to 18, wherein the first member and the second member are joined as the plurality of members by the welded portion. The first member and
A second member indirectly joined via the first member and the third member in a state where a space is formed between the first member and the first member.
Equipped with
Any one of claims 14 to 18, wherein at least one of the first member and the third member, and the second member and the third member is joined as the plurality of members by the welded portion. The products listed in one. A fluid medium housed in the space is provided.
The product according to claim 19 or 20, wherein the welded portion welds the plurality of members in a state where the welded portion prevents the fluid medium from leaking out of the space. With a plurality of members each having an end edge extending in the second direction and forming an end portion overlapping in the first direction in a state where each of the end edges is arranged in the first direction intersecting with the second direction. ,
A welded portion obtained by welding the edges of the members adjacent to each other in the first direction among the plurality of members.
Equipped with
The welded part is
As well as extending in the second direction,
When the end is viewed from the outside of the end along the first direction and a third direction intersecting the second direction, the end is exposed at intervals from both ends of the first direction. The product. The welded part is
A weld metal extending in a third direction intersecting the first direction and the second direction from the surface extending in the first direction and the second direction of the end including the edge adjacent to the first direction. When,
The heat-affected zone located around the weld metal and
Have,
22. The product according to claim 22, wherein the weld metal has an aspect ratio of the depth in the third direction to the width in the first direction of 1 or more and 5 or less. The product according to claim 23, wherein the aspect ratio is 1.5 or more and 5 or less.

Images