METHOD AND APPARATUS FOR ROUGHNING METAL SURFACE

Abstract

To provide a method of roughening metal surface, the method capable of forming unevenness having a minute height difference of several μm order including a sputter on a metal surface, and a roughening device.SOLUTION: A roughening device includes: a laser oscillator 2; a laser head 4 that irradiates a surface Wa of a steel material W with laser light L supplied from the laser oscillator 2; a scanning mechanism 8 that scans the surface Wa of the steel material W with the laser light L from the laser head 4; and a control unit 10 that controls operation of the laser head 4 and the scanning mechanism 8. The control unit 10 controls the laser head 4 and the scanning mechanism 8 with laser conditions set in order to form unevenness having a minute height difference of several μm order including a sputter on the surface Wa of the steel material W.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a method and apparatus for roughening a metal surface used for preparing a base material when coating a metal surface. [Background technology]

[0002] As described above, when painting a metal surface, it is necessary to carry out surface preparation to give the metal surface an appropriate roughness before painting in order to increase the adhesion of the paint and improve the durability of the paint.

[0003] Conventionally, a method for roughening a metal surface by adjusting its base surface is, for example, a blasting process, in which abrasive particles are struck against the metal surface by an air blasting machine or a shot blasting machine to adjust the roughness of the metal surface.

[0004] However, this blasting process requires large-scale equipment such as air blasting machines or shot blasting machines, and in addition, the abrasive particles scatter around the metal, making it difficult to use outside of a factory, for example, at sites where existing structures such as bridges and buildings are being repainted.

[0005] As an alternative method for roughening a metal surface to blasting treatment, which is difficult to perform outside a factory, there is, for example, a method for roughening a metal molded body described in Patent Document 1.

[0006] This method of roughening a metal molded body is a method used when integrating a metal molded body and a resin molded body to manufacture a composite part.In this roughening method, in order to increase the bonding strength between the metal molded body and the resin molded body, laser light is irradiated onto the metal molded body to form irregularities on the surface of the metal molded body with a height difference of more than 100 μm. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 5774246 Summary of the Invention [Problem to be solved by the invention]

[0008] The above-mentioned surface roughening method for forming irregularities with a height difference of more than 100 μm on the surface of a metal molded body is sufficiently effective for increasing the bonding strength between the metal molded body and the resin molded body of a composite part. However, this method of roughening a metal molded body is not suitable for roughening a metal surface before painting, where it is required to increase the adhesion of paint, that is, for roughening a metal surface where it is required to create minute irregularities on the metal surface with height differences on the order of a few μm.

[0009] Therefore, in roughening a metal surface by irradiating it with laser light, it is desirable to establish laser conditions that can create finer irregularities on the metal surface, and solving this has been a conventional problem.

[0010] The present disclosure has been made to solve the above-mentioned problems of the conventional art, and aims to provide a method and apparatus for roughening a metal surface that is capable of forming minute irregularities with height differences on the order of a few μm, including sputter, on the surface of a metal before painting, thereby improving the durability of the paint. [Means for solving the problem]

[0011] A first aspect of the present disclosure is a method for manufacturing a semiconductor device comprising: Steel materials that make up bridges or steel towers A method for roughening a metal surface for surface preparation, comprising irradiating the metal surface with a laser beam under laser conditions in which the average output of the laser beam, which is a pulsed laser beam set to form minute irregularities on the surface of the metal with height differences of the order of several μm including sputtering, is at least 0.7 mJ, calculated by dividing the average output of the laser beam by the repetition frequency, and the peak output of the laser beam is at least 7.0 kW.

[0014] Ma In addition, the first aspect of the present disclosure 2In this embodiment, the laser conditions are such that the pulse energy is at least 0.7 mJ, and the pulse width (time width of the pulse) of the laser light is 100.0 ns or less in order to make the peak output of the laser light at least 7.0 kW.

[0015] On the other hand, the third aspect of the present disclosure is Steel materials that make up bridges or steel towers A metal surface roughening device for adjusting the base material of a surface comprises a laser oscillator, a laser head which irradiates the metal surface with laser light, which is a pulsed laser light supplied from the laser oscillator, a scanning mechanism which scans the metal surface with the laser light from the laser head, and a control unit which controls the operation of the laser head and the scanning mechanism, wherein the control unit is configured to control the laser head and the scanning mechanism under laser conditions in which the pulse energy, calculated by dividing the average output of the laser light by the repetition frequency, is at least 0.7 mJ and the peak output of the laser light is at least 7.0 kW, the pulse energy being set to form minute irregularities on the metal surface with a height difference of the order of several μm, including sputters.

[0016] In the metal surface roughening method and roughening device according to the present disclosure, a fiber laser, a semiconductor laser, or a YAG laser is generally used as the laser, but the laser is not limited to these. Effect of the Invention

[0017] The metal surface roughening method and roughening device disclosed herein can form minute irregularities with height differences on the order of a few μm, including sputters, on the surface of the metal before painting, thereby providing the extremely advantageous effect of improving the durability of the paint. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 is a schematic explanatory diagram showing a roughening device used in a method for roughening a metal surface according to an embodiment of the present disclosure. [Diagram 2]2 is a graph showing the change over time in the pulse laser output irradiated from the laser head of the metal surface roughening device in FIG. 1. [Diagram 3] FIG. 2 is an enlarged cross-sectional view showing a metal surface after base material conditioning obtained under laser condition No. 1 in a method for roughening a metal surface according to an embodiment of the present disclosure. [Figure 4] FIG. 11 is an enlarged cross-sectional view showing a metal surface after substrate preparation obtained under laser condition No. 2 according to a comparative example. [Diagram 5] FIG. 11 is an enlarged cross-sectional view showing a metal surface after substrate conditioning obtained under laser condition No. 3 according to a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. FIG. 1 shows a roughening apparatus used in a method for roughening a metal surface according to an embodiment of the present disclosure.

[0020] As shown diagrammatically in FIG. 1, this roughening device 1 is for performing base preparation of the surface Wa of a steel material (metal) W that constitutes, for example, a bridge, and is equipped with a laser oscillator 2, a laser head 4 that collects laser light L supplied from the laser oscillator 2 via an optical fiber 5 using an incorporated optical system 3 and irradiates the surface Wa of the steel material W, a head driving mechanism 6 that moves the laser head 4 along the long side direction of the steel material W, a scanning mechanism 8 that reflects the laser light L irradiated from the laser head 4 and moves it back and forth on the surface Wa of the steel material W, and a control unit 10 that controls the output of the laser light L irradiated from the laser head 4, etc., based on the laser conditions described below. In this embodiment, a pulsed laser oscillator is used as the laser oscillator 2, which is capable of performing a roughening process with high processing accuracy and little thermal influence.

[0021] The head drive mechanism 6 includes a rail 6a arranged along the long side direction of the steel material W, and a slider 6b that reciprocates on the rail 6a. In this case, the laser head 4 is fixed to the slider 6b so that the laser light irradiation direction is aligned in a direction parallel to the surface Wa of the steel material W and perpendicular to the rail 6a.

[0022] In addition, the scanning mechanism 8 is held in a case 9 attached to the slider 6b of the head driving mechanism 6 via a support base 7, and is composed of a scanner mirror 8a that reflects the laser light L from the laser head 4, and a scanner motor 8b that rotates this scanner mirror 8a in small increments within a predetermined range.

[0023] In other words, in this roughening device 1, by operating both the head driving mechanism 6 and the scanning mechanism 8, the laser light L is moved to cover the entire surface Wa of the steel material W, thereby forming minute irregularities with a height difference of the order of several μm, including the resulting sputter, on the surface Wa of the steel material W.

[0024] More specifically, the scanner mirror 8a of the scanning mechanism 8, which reflects the laser light L, is rotated in small increments to move the laser spot S on the surface Wa of the steel material W along the short side direction of the steel material W by a predetermined amount for each pulse (1 / 4 of the diameter of the laser spot S in this embodiment), as shown in the enlarged oval in Figure 1.

[0025] On the other hand, the head driving mechanism 6 is operated each time the movement of the laser spot S along the short side direction of the steel material W is completed, and moves the laser spot S a predetermined amount (1 / 4 of the diameter of the laser spot S in this embodiment) along the long side direction of the steel material W.

[0026] The amount of movement of the laser spot S per pulse by the head driving mechanism 6 and the scanning mechanism 8 is not limited to 1 / 4 of the diameter of the laser spot S described above, but in order to avoid gaps between adjacent laser spots S, it is desirable to move the laser spot S within the range of 1 / 4 to 3 / 4 of the diameter of the laser spot S.

[0027] In this case, the control unit 10 controls the laser head 4, head driving mechanism 6 and scanning mechanism 8 under laser conditions set to form minute irregularities with height differences on the order of a few μm, including sputters, on the surface Wa of the steel material W.

[0028] Here, Fig. 2 shows the change over time in the pulse laser output irradiated from the laser head 4 of the roughening device 1. In Fig. 2, the symbols Pa and Pp respectively indicate the average output and the peak output, and the symbols In and w respectively indicate the pulse interval and the pulse width (time width of the pulse) of the laser light L. Also in Fig. 2, the symbol PE indicates the pulse energy.

[0029] In determining the above laser conditions, first, the spot diameter is set to about 60 μm, the pulse energy PE obtained by dividing the average output Pa of the laser light L by the repetition frequency expressed as the reciprocal of the pulse interval In is set to at least 0.7 mJ, and the peak output Pp of the laser light L is set to at least 7.0 kW.

[0030] In order to set the pulse energy PE to at least 0.7 mJ as described above and the peak output power Pp of the laser light L to at least 7.0 kW, the pulse width w of the laser light L is set to 100.0 ns or less.

[0031] In this manner, in the present embodiment, the control unit 10 controls the laser head 4, the head driving mechanism 6, and the scanning mechanism 8 so that the pulse energy PE, which is obtained by dividing the average output power Pa of the laser light L by the pulse repetition frequency, is at least 0.7 mJ, and the peak output power Pp of the laser light L is at least 7.0 kW, so that the pulse width w of the laser light L is 100.0 ns or less.

[0032] Therefore, the surface Wa of the steel material W constituting the bridge was roughened under condition No. 1 in this embodiment shown in Table 1 and condition No. 2 set as a comparative example. Table 1 also lists condition No. 3 as another comparative example, which was set so that minute irregularities on the surface Wa disappeared regardless of the various conditions.

[0033] [Table 1] * The repetition frequency, pulse width and pulse energy for condition No. 2 are: The upper row shows the value when the average output is 50W, and the lower row shows the value when the average output is 50W. This value is for an average output of 25W.

[0034] The surface roughening treatment under condition No. 1 gave the results shown in Figure 3, while the surface roughening treatment under condition No. 2 gave the results shown in Figure 4. Moreover, the surface roughening treatment under condition No. 3 gave the results shown in Figure 5.

[0035] As can be seen from Fig. 3, in the roughening treatment under condition No. 1, minute irregularities G with height differences on the order of several µm, including spatter Sp, are formed on the surface Wa of the steel material W. In contrast, as can be seen from Fig. 4, in the roughening treatment under condition No. 2, although larger irregularities are found on the surface Wa of the steel material W, minute irregularities are not found. Also, as can be seen from Fig. 5, in the roughening treatment under condition No. 3, no irregularities are generated on the surface Wa of the steel material W.

[0036] Therefore, it has been demonstrated that the metal surface roughening method and roughening device 1 according to this embodiment can form minute irregularities G with height differences on the order of several μm, including sputters Sp, on the surface Wa of the steel material W.

[0037] In addition, the metal surface roughening method and roughening device 1 of this embodiment can form minute irregularities G with height differences on the order of several μm, including spatter Sp, on the surface Wa of the steel material W, thereby improving the durability of the coating. Furthermore, in the metal surface roughening method and roughening device 1 according to the present embodiment, a pulsed laser oscillator is used as the laser oscillator 2, so that high-precision roughening processing can be performed while minimizing thermal effects.

[0038] In the above-described embodiment, the metal surface roughening method and roughening device disclosed herein are used to roughen the surface Wa of a steel material (metal) W constituting a bridge, but this is not limited to this, and it is of course possible to apply the metal surface roughening method and roughening device disclosed herein to roughening the surface Wa of a steel material W constituting a steel tower, for example.

[0039] The configuration of the method and apparatus for roughening a metal surface according to the present disclosure is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit and scope of the disclosure. [Explanation of symbols]

[0040] 1. Roughening device 2 Laser Oscillator 4 Laser Head 8 Scanning Mechanism 8a Scanner mirror 8b Scanner motor 10 Control section G Minor irregularities In Pulse Interval L Laser light PE Pulse Energy Pa average power Pp Peak power Sp Sputter W Steel material (metal) Wa Steel surface (metal surface) w Pulse duration

Claims

1. A method for roughening a metal surface by adjusting the base surface of a steel material constituting a bridge or a steel tower, comprising the steps of: A method for roughening a metal surface, comprising irradiating a laser beam to the surface of the metal under laser conditions in which the laser beam is a pulsed laser beam set to form minute irregularities on the surface of the metal with height differences on the order of several μm, including sputters, and the pulse energy, calculated by dividing the average output of the laser beam by the repetition frequency, is at least 0.7 mJ, and the peak output of the laser beam is at least 7.0 kW.

2. 2. The method for roughening a metal surface according to claim 1, wherein the laser conditions include a pulse energy of at least 0.7 mJ and a pulse width of the laser beam of 100.0 ns or less to achieve a peak output of the laser beam of at least 7.0 kW.

3. A metal surface roughening device for adjusting the surface of steel materials constituting a bridge or a steel tower, comprising: A laser oscillator; a laser head that irradiates a surface of the metal with a laser beam that is a pulsed laser beam supplied from the laser oscillator; a scanning mechanism for scanning the laser light from the laser head on the surface of the metal; a control unit for controlling the operation of the laser head and the scanning mechanism, The control unit of the metal surface roughening device controls the laser head and the scanning mechanism under laser conditions in which the average output of the laser light is set to form minute irregularities on the surface of the metal with a height difference of the order of a few μm, including sputters, and the pulse energy, calculated by dividing the average output of the laser light by the repetition frequency, is at least 0.7 mJ, and the peak output of the laser light is at least 7.0 kW.

Images