JPH0645071B2 - Bimetal plate manufacturing method - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a method for manufacturing a bimetal plate having a two-layer structure and a three-layer structure, in which the irradiation surfaces of a laser beam are opposed to each other and are cold-welded to obtain surface quality and adhesion. The present invention relates to a manufacturing method for obtaining a bimetal plate having excellent strength.

BACKGROUND ART In general, a two-layered bimetal composed of a high expansion side alloy and a low expansion side alloy is used for parts for thermal control equipment, and an intermediate layer between the high expansion side alloy and the low expansion side alloy. The three-layered bimetal in which an alloy is interposed and pressure-bonded is used for a current breaker or the like, but all are manufactured in the same process.

As an example, a method of manufacturing a two-layered bimetal will be described. First, while rewinding the high expansion side alloy coil and the low expansion side alloy coil, the surface to be pressure-welded is cleaned by a mechanical polishing method such as a wire buff. After that, cold pressure welding,
Diffusion annealing, intermediate cold rolling and intermediate annealing, finish cold rolling.

However, in mechanical polishing such as wire buff polishing, there is a possibility that minute cracks due to polishing, scale-like metal powder generation, adhesion, and foreign matter may remain on the required polishing surface for pressure welding. There is a problem that the metal powder and the foreign matter are entrained on the pressure contact surface, and the bimetal plate is peeled off as the adhesion strength is reduced.

An object of the present invention is to eliminate the problems caused by the cleaning of the surface of the alloy plate on the high expansion side and the alloy surface on the low expansion side in the conventional method for manufacturing a bimetal plate, improve the crimping strength, and improve the quality of the bimetal plate. It is aimed at a manufacturing method by which a plate is obtained.

Structure and effect of the invention This invention, as a result of various studies for the purpose of cleaning the surfaces of the high expansion side and low expansion side alloy plates in the method of manufacturing a bimetal plate, improving the bonding strength, and improving the quality of the bimetal plate, A laser beam is radiated in a zigzag shape, a meandering shape, or a striped shape on the surface to be pressure-welded on the both alloy plates.
By irradiating with a laser beam having a wavelength that is easily absorbed by foreign matter, fats and oils, which cause bonding failure, foreign matter, fats and oils adhering to the surface are absorbed by the laser light, gasified and removed. A clean surface can be obtained, and when the irradiation surfaces of the alloy plate are pressed together, an atomic bond easily occurs because the surface is clean, and practically sufficient adhesive strength within a range that does not make a difference can be obtained. I found out.

Furthermore, if a laser beam with a wavelength that is easily absorbed by both alloy plates and intermediate metal plates as well as foreign substances is used, that is, if a laser beam with a wavelength of 5 μm or less is used, the extreme surface layer of 10 μm or less, preferably submicron order, is melted. When solidified to form a hardened layer, and during cold pressure welding of the metal and pressure-bonded material, a fine crack is generated on the surface of the hardened layer on the substrate surface due to internal slip deformation, thereby exposing the new internal surface. It can significantly improve the adhesion strength between both alloy plates or the intermediate layer metal plate and both alloy plates, and prevents surface cracks, metal powder, and residual foreign substances from adhering and adhering due to mechanical polishing of conventional wire buffs. The inventors have completed the present invention by finding that a bimetal plate that can be manufactured and has high pressure contact strength and excellent quality can be obtained.

That is, in the present invention, in the case of a bilayer structure bimetal plate, in the method for manufacturing a bimetal plate in which a high expansion side alloy plate and a low expansion side alloy plate are pressure-welded, one surface of the high expansion side alloy plate and the low expansion side alloy plate is A method for manufacturing a bimetal plate, which comprises irradiating a laser beam, and bringing the surfaces to be pressure-welded, including the irradiation layers formed by the irradiation of both plates, to face each other and cold-welding them.

Further, in the case of a three-layer structure bimetal plate, in the manufacturing method of the bimetal plate in which the high expansion side alloy plate and the low expansion side alloy plate are pressure-welded with the intermediate layer metal plate interposed, in the high expansion side alloy plate and the low expansion side alloy plate The entire surface of one side and the entire surfaces of both sides of the intermediate layer metal plate are irradiated with a laser beam, the intermediate layer metal plate having the irradiation layer formed by the irradiation is sandwiched on both sides, and both alloy plates are formed by the irradiation. In the method of manufacturing a bimetal plate, the surfaces to be pressure-welded including the irradiation layer are opposed to each other, and three sheets are cold-pressed at one time.

Alternatively, if necessary, one side of the high expansion side alloy plate or the low expansion side alloy plate and one side of the intermediate metal plate are irradiated with a laser beam, and an intermediate layer metal plate having an irradiation layer formed by the irradiation on one side, Cold welding is performed with the surfaces to be pressure-welded including the irradiation layer of the alloy plate facing each other, and the laser beam is applied to the other surface of the low expansion side alloy plate or the high expansion side alloy plate remaining on the other surface of the intermediate layer metal plate side after the pressure welding. Cold welding is performed by irradiating a beam and facing the other surface of the intermediate metal plate after pressure welding and the surface of the remaining low expansion side alloy plate or high expansion side alloy plate that includes the irradiation layer formed by this irradiation You can do it.

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the high expansion side alloy plate is a Fe alloy containing Ni17wt% to 26wt% and one of Cr2.5wt% to 12wt%, Mn5wt% to 7wt% and Mo3wt% to 7wt%. Mn alloys containing 70 wt% to 80 wt% of Mn, 5 wt% to 15 wt% of Ni, and the balance Cu, and Fe alloys containing 35 wt% to 50 wt% of Ni or 13 wt% to 18 wt% of Cr can be used for the low expansion side alloy plate.

In the present invention, the high expansion side Fe alloy plate is not preferable because the thermal expansion coefficient becomes too small when Ni is less than 17 wt% and the thermal expansion coefficient becomes too small when it exceeds 26 wt%. Also, Mn is less than 5 wt%, Cr is less than 2.5 wt%, Mo3 wt%
If it is less than Mn, it is not preferable in terms of stability of high expansion property, and Mn
If it exceeds 7 wt%, the corrosion resistance will deteriorate, and if Cr is 12 wt
%, Or Mo exceeds 7 wt%, workability deteriorates, which is not preferable.

Therefore, the high-expansion side Fe alloy sheet has Ni17wt% ~ 26wt%, Mn5wt% ~ 7wt% or Cr2.5wt% ~ 1
Fe alloy containing one of 2 wt% or Mo3 wt% to 7 wt%, especially Ni19-21-Cr5-7.0-Fe alloy (wt%), Ni19.0-23-Cr2.5-5.0-Fe alloy ( wt%), Ni17.0 to 20.0-Cr10.0 to 12.0-Fe alloy (wt%), Ni23 to 27-Mo3.0 to 7.0-Fe alloy (wt%), Ni19.0 to 24.0-Mn5.0 to 7.0-Fe alloy (wt%) is preferred.

Also, as a Mn alloy that can obtain a high expansion coefficient, Mn70wt% ~
An Mn alloy consisting of 80 wt%, Ni 5 wt% to 15 wt% and the balance Cu is preferable.

Also, the Fe alloy plate on the low expansion side has less than 35 wt% Ni and 13 wt% Cr.
%, The coefficient of thermal expansion becomes too large, and Ni is 50
If the content of Cr exceeds 18 wt% and the content of Cr exceeds 18 wt%, the coefficient of thermal expansion similarly becomes too large, which is not preferable.
Fe alloy containing 50wt% or Cr13wt-18wt%, amber alloy, Ni38wt% -Fe alloy, Ni42wt% -Fe alloy, Cr
A 13-18 wt% Fe alloy is preferred.

The intermediate-layer metal plate may be appropriately selected from a Ni alloy or a Cu alloy in accordance with its application or the like in order to adjust the electric resistance of the bimetal plate.

In the present invention, the laser beam irradiation method is such that a spot-shaped beam travels two-dimensionally by using a mirror on both surfaces of the intermediate metal plate and the surface of the high-low expansion alloy plate to be pressed, or a lens and a mirror are used. And spread the beam to irradiate the plate width direction at once to irradiate the entire surface to be adhered uniformly, or zigzag the beam on the surface to be adhered, meander, or partially irradiate in stripes. It is a thing.

Further, in the present invention, the surface state of the alloy plate or the intermediate metal plate which is partially irradiated with the laser beam is, as described above, formed by forming the hardened layer by cleaning the irradiated surface and melting and solidifying the extreme surface layer. The surface of the irradiated portion is also cleaned by the thermal effect of the surrounding irradiated portion. Therefore, when one side of the high expansion side alloy plate and the low expansion side alloy plate and / or both sides of the intermediate layer metal plate is irradiated with a laser beam, cold welding is performed through the alloy plate or the intermediate layer metal plate, As described above, in the irradiated part, the high and low expansion alloy plates are firmly adhered to each other or through the intermediate metal plate, and the surface of the non-irradiated part is cleaned. Adhesion with and is improved and sufficient adhesive strength is obtained.

In the present invention, the irradiation of the laser beam is sufficient if it is possible to remove the deposits, oils and water on the surface, and preferably 10
Any method may be used as long as it is possible to melt and solidify the extremely surface layer having a thickness of μm or less. For example, the beam is focused in a spot shape and irradiated in the direction orthogonal to the surface of the alloy plate, or the alloy plate and the laser beam are alloyed. It is possible to adopt a method of moving the plate in the same direction or in the opposite direction to the longitudinal direction of the plate, and further, moving the plate in the longitudinal direction of the plate while oscillating the laser beam in the amplitude direction.

Further, a method in which a laser beam is oscillated from a laser oscillator, condensed by a collimator and a lens, and guided to a required position by an optical fiber for irradiation is also employable.

In this invention, as the irradiation conditions of the laser beam,
Power density of the beam is preferably in the range of ^{100kW / mm 2 ~1500kW / mm 2} , more ^{preferably, 300kW / mm 2 ~900kW / mm} 2
Is.

If the power density of the laser beam is less than 100 kW / mm ² , the surface cleaning effect on the pressure welding is not effective and 1500 kW / mm ²
If it exceeds, the surface irregularities become severe, and holes are generated in the plate as the power density increases, which is not preferable.

Further, if the laser wavelength is 5 μm or less, it is effective, but if it exceeds 2 μm, the absorption effect on the alloy plate decreases, so it is desirable to use a wavelength of 2 μm or less.

Furthermore, in order to improve the irradiation efficiency of the laser beam, before irradiating the required surface of the high-low expansion both alloys or both surfaces of the intermediate layer metal plate with the laser beam, preheat to 200 ℃ ~ 500 ℃ in a non-oxidizing atmosphere. Preferably.

Disclosure Based on Drawings of the Invention FIG. 1 is a perspective explanatory view of an alloy plate showing laser beam irradiation and pressure welding according to the present invention.

The high expansion side alloy plate (1) coil is uncoiled and advances toward the cold pressure roll (2). An irradiation box (3) for irradiating a laser beam on the upper surface of the passing alloy plate (1) is arranged behind the pressure contact roll (2).
(3) surrounds the entire alloy plate (1), has Ar gas vented inside, and has a configuration capable of irradiating a laser beam in an Ar gas atmosphere.

The laser beam is emitted by the YAG
After being oscillated from the laser oscillator of the laser, passed through the collimator, reflected at the required angle by the galvanic mirror (5), condensed by the fθ lens (6) and focused,
The fθ lens (6) position is adjusted so that the required width portion of the alloy plate (1) can be irradiated at a position away from the focal point by a required distance. Four such irradiation devices are provided, the alloy plate (1) width direction. Are arranged in parallel with each other, and a laser beam can be applied to the entire plate width.

The laser beam generator used in the present invention can increase the laser scanning speed by using a polyhedral mirror or a segment mirror in place of the galvanic mirror (5), and also uses a cylindrical lens. By collectively irradiating the plate width direction, the processing speed can be improved.

The alloy plate (1) is irradiated with a laser beam over the entire surface in the axial direction or with a laser beam in a zigzag pattern or a striped pattern, and the extreme surface layer is melted and solidified to form a new surface from which deposits, oils and water are removed. Become.

Further, in the same manner as the above laser beam irradiation, the low expansion side alloy plate wound with the irradiation surface provided on the entire one surface
(7) After the coil is uncoiled, it is fed to the pressure contact roll (2) from above the high expansion side alloy plate (1), and the low expansion alloy plate (7) is irradiated onto the irradiation surface by the laser beam irradiation. The faces are opposed and pressed together.

At this time, the molten solidified layer on the irradiated surface of both alloy plates (1) and (7) causes fine cracks on the surface due to the effect of internal slip deformation, and the newly developed internal surface is exposed and the high expansion side alloy plate (1) Since the low expansion side alloy plate (7) is pressure-welded, it is possible to obtain a bimetal plate which is superior in cleaning degree and adhesion strength and is superior in quality to the conventional mechanically polished surface.

In addition, after providing the irradiation surface of the laser beam on each of the high expansion side alloy plate (1) and the low expansion side alloy plate (7), this is wound, both alloy coils are rewound again, and both are pressure-welded. In addition, in the case of a three-layer bimetal plate structure, a high expansion alloy plate (1) is formed by interposing an intermediate metal plate whose both surfaces are individually irradiated with laser beams by the above method.
Alternatively, the low expansion side alloy plate (7) may be pressure-welded.

Therefore, it is necessary to appropriately select the oscillation method of the laser beam, the irradiation output, the distance between the focal point and the irradiation surface by the fθ lens, the moving speed on the irradiated side, etc., depending on the material and size of the constituent material of the bimetal plate.

Example For the high expansion side alloy plate, a 20% Ni-6% Cr-Fe alloy plate (w with a thickness of 2.50 mm and a width of 300 mm) (w
t%), and the low expansion side alloy plate was a plate thickness 2.5 mm, plate width 300 mm, and 36% Ni-Fe alloy plate (wt%).

The atmosphere gas in the irradiation box was Ar gas, and the moving speed of the alloy plate was 1 m / min.

As the laser irradiation device, three 100 W output, 10 kHz Q-switched lasers were used, and in the same manner as the invention of FIG. 1 described above, the lens focal length was 100 mm, the wavelength was 1.06 μm, and the laser power density was 500 kW / mm ² . Under the conditions, three strips having a width of 100 mm in the alloy plate were continuously formed in the longitudinal direction of the alloy plate to form irradiation surfaces by the laser beam.

The irradiation surfaces of the two alloy plates were opposed to each other, and cold-welding was performed at a rolling rate of 50% with a pressure-bonding roll.

Furthermore, after performing diffusion annealing, intermediate rolling, finish rolling,
Using a slitter, a bimetal plate having a two-layer structure with a plate thickness of 0.4 mm and a plate width of 50 mm was obtained.

In addition, for comparison, the same type of high expansion side alloy plate and low expansion side alloy plate were used, with 0.5 mmΦ wire rotating brush, wire buffing condition of moving speed 17 m / min, on one side of each alloy plate. After performing the mechanical polishing of, under the same conditions as above, cold pressure welding, diffusion annealing, intermediate rolling, finish rolling, and then using a slitter to obtain a bimetal plate with a plate thickness of 0.4 mm x a plate width of 50 mm. It was

The pressure-bonding strength and appearance properties of the obtained two kinds of bimetal plates were examined, and the results are shown in Table 1.

As shown in Fig. 2a, the crimping strength is obtained by cutting the bimetal plate to a length of 40 mm and then crimping the 10 mm length of the crimping part to the high expansion alloy plate (1). A test piece (10) with a T-shaped cross section that opens between the low expansion side alloy plates (7)
30 pieces were prepared and pulled in a direction perpendicular to the crimping portion, and the crimping strength was evaluated by the load when the crimping portion was peeled off.

As is clear from Table 1, according to the method of the present invention, a bimetal plate having higher pressure bonding strength and less variation than the conventional method, excellent appearance properties, and excellent quality can be obtained.

Example 2 For the high expansion side alloy plate, a 50% Mn-23% Ni-Fe alloy plate (wt%) having a plate thickness of 2 mm and a plate width of 240 mm was used.
For the low expansion side alloy plate, plate thickness 2 mm, plate width 240 mm, 38% Ni-Fe alloy plate (wt%) is used. For the intermediate metal plate, plate thickness 0.5 mm, plate width 240 mm, A 1% Fe-Ni alloy plate (wt%) was used.

The atmosphere gas in the irradiation box was Ar gas, and the moving speed of the alloy plate was 1.5 m / min.

As the laser irradiation device, three 100 W output, 10 kHz Q-switched lasers were used, and in the same manner as the invention of FIG. 1 described above, the lens focal length was 100 mm, the wavelength was 1.06 μm, and the laser power density was 500 kW / mm ² . Under the conditions, three strips having a width direction of the alloy plate of 80 mm were continuous in the longitudinal direction of each of the high expansion and low expansion alloy plates, and one surface was irradiated with a laser beam. Similarly, irradiation surfaces were formed on both sides of the intermediate metal plate.

The irradiation surfaces of the high-expansion and low-expansion alloy plates were opposed to the irradiation surfaces on both sides of the intermediate metal plate, respectively, and cold pressure welding was carried out at a rolling rate of 55% by a pressure welding roll.

Furthermore, after performing diffusion annealing, intermediate rolling, finish rolling,
A three-layer bimetal plate having a plate thickness of 0.5 mm and a plate width of 79 mm was obtained with a slitter.

For comparison, a high expansion side alloy plate, a low expansion side alloy plate, and an intermediate layer metal plate of the same kind were used, and a 0.5 mmΦ wire rotating brush was applied to the entire one side of each alloy plate and both sides of the intermediate layer metal plate. , With wire buff polishing condition of moving speed 10m / min,
After performing conventional mechanical polishing, under the same conditions as above, cold pressure welding, diffusion annealing, intermediate rolling, and charge rolling were performed, and then a bimetal plate with a plate thickness of 0.5 mm × a plate width of 79 mm was slittered. Obtained.

The pressure-bonding strength and appearance properties of the obtained two kinds of bimetal plates were examined, and the results are shown in Table 2.

As shown in Figs. 2b and 2c, the crimping strength is such that the bimetal plate is cut in the length direction by 40mm, and then the crimping part length of 10mm is opened for each layer to be measured. That is, a test piece (11) having a T-shaped cross section opened between the high expansion side alloy plate (1) and the intermediate layer metal plate (8), the intermediate layer metal plate (8) and the low expansion side alloy plate (7) Test piece with a T-shaped cross section
30 pieces of (12) were produced and pulled in a direction perpendicular to the crimping portion, and the crimping strength was evaluated by the load when the crimping portion was peeled off.

As is clear from Table 2, according to the method of the present invention, a bimetal plate having higher pressure bonding strength and less variation than the conventional method, excellent appearance properties, and excellent quality can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an alloy plate showing laser beam irradiation and pressure welding according to the present invention. FIG. 2 is an explanatory diagram of a test piece showing a test method for evaluation of pressure bonding strength. 1 ... High expansion side alloy plate, 2 ... Pressure contact roll, 3 ... Irradiation box, 4 ... Oscillator, 5 ... Galvanic mirror, 6 ... fθ
Lens, 7 ... low expansion side alloy plate, 8 ... intermediate layer metal plate, 10,1
1,12 ... Test piece

Claims (2)

[Claims] 1. A method for producing a bimetal plate in which a high expansion-side alloy plate and a low expansion-side alloy plate are pressure-welded to each other, wherein one side of the high expansion-side alloy plate and the low expansion-side alloy plate is irradiated with a laser beam,
A method for manufacturing a bimetal plate, characterized in that the surfaces to be pressure-welded including the irradiation layer formed by the irradiation of both plates are opposed to each other and cold-welded. 2. A method for producing a bimetal plate in which a high-expansion side alloy plate and a low-expansion side alloy plate are pressure-welded with an intermediate-layer metal plate interposed therebetween, wherein one side of the high-expansion side alloy plate and the low-expansion side alloy plate and the intermediate layer. Irradiating a laser beam on both sides of the metal plate, sandwiching an intermediate metal plate having an irradiation layer formed by the irradiation on both sides, and opposing pressure contact surfaces including an irradiation layer formed by the irradiation of both alloy plates facing each other. A method for manufacturing a bimetal plate, which comprises cold welding.