阅读说明：本技术 一种表面具有凹坑结构的轧辊及其制备方法 (Roller with pit structure on surface and preparation method thereof ) 是由 陈孝明 全基哲 李山青 陈军 于 2020-05-27 设计创作，主要内容包括：本发明公开了一种表面具有凹坑结构的轧辊及其制备方法,所述轧辊表面上设有多个凹坑；所述凹坑均设置为椭圆形；所述凹坑沿所述轧辊表面以螺旋路径分布；所述轧辊圆周方向上的相邻所述凹坑之间的间距随机设定。本发明改善了表面微观形貌的不均匀性,从而改善涂装效果。(The invention discloses a roller with a pit structure on the surface and a preparation method thereof, wherein a plurality of pits are arranged on the surface of the roller; the pits are all oval; the dimples are distributed along the roll surface in a spiral path; the distance between the adjacent concave pits in the circumferential direction of the roller is randomly set. The invention improves the nonuniformity of surface micro-morphology, thereby improving the coating effect.)

1. A roll with a pit structure on the surface is characterized in that:

a plurality of pits are arranged on the surface of the roller;

the pits are all oval;

the dimples are distributed along the roll surface in a spiral path;

the distance between the adjacent concave pits in the circumferential direction of the roller is randomly set.

2. A roll having a dimpled surface structure as claimed in claim 1 wherein: the ratio of the major axis to the minor axis of the pits is less than 2.

3. A preparation method of a roller with a pit structure on the surface is characterized by comprising the following steps:

1) placing the roller on a chuck clamp of a numerical control machine tool for clamping, and enabling the roller to rotate around the axis of the roller at a constant rotating speed;

2) adjusting the position of a laser focusing head on a numerical control machine tool to enable the focusing focus of the laser focusing head to fall on the surface of a roller;

3) moving a laser focusing head at a constant speed along the parallel direction of the axis of the roller;

4) controlling laser pulses emitted by a laser on a numerical control machine tool by using digital pulse signals with consistent opening time and random variation of closing time, and bombarding the laser pulses on the surface of the roller by a laser focusing head to form the roller according to claim 1 or 2.

4. The method for producing a roll having a dimpled structure on its surface according to claim 3, wherein: in the step 1), the rotating speed of the roller is 100-300 rpm.

5. The method for producing a roll having a dimpled structure on its surface according to claim 3, wherein: in the step 3), the moving range of the laser focusing head is 0.05-0.15 mm when the roller rotates for one circle.

6. The method for producing a roll having a dimpled structure on its surface according to claim 3, wherein: in the step 4), the digital pulse signal is generated by a single board computer or a control card.

7. The method for producing a roll having a dimpled structure on its surface according to claim 3, wherein: in the step 4), the consistent opening time refers to consistent duration time of the digital pulse signal in a high level state, and is set to a value between 2 μ s and 50 μ s.

8. The method for producing a roll having a dimpled structure on its surface according to claim 3, wherein: in the step 4), the random variation of the turn-off time specifically means that the duration of each pulse of the digital pulse signal in the low level state is randomly varied within a certain range, the lower limit of the range is not lower than 2 μ s, and the upper limit of the range is not higher than 150 μ s.

9. The method for producing a roll having a dimpled structure on its surface according to claim 3, wherein: the laser is a modulated laser.

Technical Field

The invention relates to a roller surface treatment technology, in particular to a roller with a pit structure on the surface and a preparation method thereof.

Background

In recent years, with the increasing demand of automobile factories for the coating quality of steel plates, the demand for the microstructure of the surface of the steel plates is higher and higher, and further research finds that the microstructure of the surface of the steel plates is random, so that large pits may exist in a certain local area, and large bosses may exist in another area, and when the size of the pits or the bosses exceeds a certain value, the unevenness of the microstructure is difficult to cover by the coating, and the microstructure represented by the coating after coating is uneven, thereby affecting the coating quality.

For example, publication No. CN104884180B (published 2015, 9, 2), discloses a flat sheet product made of a metal material, in particular a steel material, the use of the flat sheet product, a roll and a method for producing the flat sheet product, being a rolling roll having a double I-shaped, H-shaped, cross-shaped, C-shaped or X-shaped deterministic texture. Although the technical scheme can realize the fine design and processing of the surface microstructure and improve the nonuniformity of the microstructure, the surface appearance of the roller is a texture appearance with a specific rule, so that the defect of moire fringes is easily generated.

For example, in publication No. CN104210212B (published as 2014, 12, 17), a laminating roller is disclosed, which obtains a random surface structure by randomly changing the switching time and laser power of laser pulses, wherein the surface structure has coarse and large roughened pits, and also has small roughened pits, so that the surface microstructure has low uniformity, and microscopic unevenness is easily generated during coating.

In summary, although some technicians do some work on controlling the surface micro-topography, it is still desirable to obtain a roller with a specific surface structure and a corresponding manufacturing method, which can effectively improve the non-uniformity of the surface topography of the roller, and at the same time, have a certain degree of disorder, and avoid the defect of moire fringes.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a roller with a pit structure on the surface and a preparation method thereof, which improve the nonuniformity of surface micro-morphology and further improve the coating effect.

In order to achieve the purpose, the invention adopts the following technical scheme:

in one aspect, a roll having a dimpled structure in its surface:

a plurality of pits are arranged on the surface of the roller;

the pits are all arranged to be oval, and the shape, size and depth of each pit are basically consistent;

the dimples are distributed along the roll surface in a spiral path;

the distance between the adjacent concave pits in the circumferential direction of the roller is randomly set.

Preferably, the ratio of the major axis to the minor axis of the pits is less than 2.

In another aspect, a method for preparing a roll with a pit structure on the surface comprises the following steps:

1) placing the roller on a chuck clamp of a numerical control machine tool for clamping, and enabling the roller to rotate around the axis of the roller at a constant rotating speed;

2) adjusting the position of a laser focusing head on a numerical control machine tool to enable the focusing focus of the laser focusing head to fall on the surface of a roller;

3) moving a laser focusing head at a constant speed along the parallel direction of the axis of the roller;

4) and controlling laser pulses emitted by a laser on the numerical control machine tool by using digital pulse signals with consistent opening time and random variation of closing time, and bombarding the laser pulses on the surface of the roller by using a laser focusing head to form the roller.

Preferably, in the step 1), the rotation speed of the roller is related to the desired density of the periphery of the textured point, and the value is generally 100 to 300 rpm.

Preferably, in the step 3), the constant speed of the laser focusing head is related to the desired axis density of the textured points, the higher the density of the textured points is, the slower the moving speed is, and generally, the moving range of the laser focusing head is 0.05-0.15 mm per rotation of the roller.

Preferably, in step 4), the digital pulse signal is generated by a single board computer or a control card.

Preferably, in the step 4), the consistent turn-on time refers to a consistent duration of the digital pulse signal in the high level state, and the duration is set to a value between 2 μ s and 50 μ s according to different requirements of the target roughness.

Preferably, in the step 4), the random variation of the turn-off time specifically means that the duration of each pulse of the digital pulse signal in the low level state is randomly varied within a certain range, the lower limit of the range is not lower than 2 μ s, and the upper limit of the range is not higher than 150 μ s.

Preferably, the laser is a modulated laser capable of responding to an external control signal, and when the external control signal is in a high level state, the laser emits light, and when the external control signal is in a low level state, the laser stops emitting light and emits pulse laser under pulse signal modulation.

In the technical scheme, the roller with the pit structure on the surface and the preparation method thereof provided by the invention have the advantages that the microstructure of the roller surface is a surface structure with pits of basically consistent size and depth and random distribution, the nonuniformity of surface microstructure is improved, and the coating effect is improved.

Drawings

FIG. 1 is a schematic view of the surface microstructure of example 1 of the roll of the present invention;

FIG. 2 is an enlarged schematic view of portion A of FIG. 1;

FIG. 3 is a schematic view of a numerically controlled machine tool used in embodiment 1 of the method of the present invention;

FIG. 4 is a schematic diagram showing the correspondence between laser pulses and textured pits in example 1 of the method of the present invention;

FIG. 5 is a schematic view of the surface microstructure of roll example 2 of the present invention;

FIG. 6 is a schematic representation of the surface microstructure of roll example 3 of the present invention.

Detailed Description

The technical scheme of the invention is further explained by combining the drawings and the embodiment.

Example 1

Referring to fig. 1 to fig. 2, the present invention provides a roll with a pit structure on a surface thereof:

the surface of the roller is composed of a large number of scattered oval texturing pits 5, the length of each texturing pit 5 is about 70 mu m, the width is about 50 mu m, the depth is about 22 mu m, the ratio of the long axis to the short axis of each texturing pit 5 is 1.4, the texturing pits 5 are distributed on a spiral path with the pitch of 60 mu m on the roller surface of the roller 1, and the distance between the texturing pits 5 in the circumferential direction of the roller 1 is randomly changed from 80 mu m to 120 mu m.

Referring to fig. 3 to 4, the present invention further provides a method for manufacturing a roller with a pit structure on a surface thereof, including:

and clamping the roller 1 on a numerical control machine tool 4, and enabling the roller 1 to keep constant-speed rotation motion around the axis of the roller 1, wherein the diameter of the roller 1 is 452mm, and the rotation speed is set to be 150 rpm.

The laser focusing head 2 is mounted on a supporting plate 401 of the numerical control machine 4, can move back and forth, and is adjusted to be in a position that a focusing focus of the laser focusing head falls on the surface of the roller 1.

The numerically-controlled machine tool 4 is used for driving the laser focusing head 2 to move from one end of the roll surface of the roller 1 to the other end at a constant speed of 9mm/min, which is equivalent to that the laser focusing head travels by 60 micrometers every time the roller 1 rotates one circle.

The fiber laser 3 is installed on a supporting plate 401 of a numerical control machine tool 4, moves along with the supporting plate 401, emits laser pulses and transmits the laser pulses to a laser focusing head 2, the power of the laser is set to be 400w, the laser is set to be in an external modulation signal control mode, as shown in fig. 4, the on-off of the laser is controlled by digital pulse level signals with pulse on-time of 11 mus and off-time of 11-22 mus which randomly change, so that textured pits with the same depth and randomly changed intervals are formed on the surface of the roller, and finally the roller 1 shown in fig. 1 is completed.

Example 2

As another preferred embodiment of the present invention, compared with example 1, the roughened pit has a certain overlap amount in the circumferential direction and the axial direction, as shown in FIG. 5, which is mainly different from example 1 in the processing method in that the translation speed of the laser focusing head is reduced and the pulse off time is reduced, the translation speed of the laser focusing head is set to 6mm/min, and the pulse off time is set to 8 to 14 μ s.

Example 3:

as another preferred embodiment of the present invention, compared with example 1, the random range of the intervals between the textured dots in the circumferential direction of the textured pits is made larger, and some of the textured dots overlap in the circumferential direction, as shown in FIG. 6, and the main differences in the processing method compared with example 1 are that the pulse-on time is set to 8 μ s and the pulse-off time is set to 6 to 27 μ s, which are reduced and the range of the pulse-off time is increased.

It should be understood by those skilled in the art that the above embodiments are only for illustrating the present invention and are not to be used as a limitation of the present invention, and that changes and modifications to the above described embodiments are within the scope of the claims of the present invention as long as they are within the spirit and scope of the present invention.