ROLL FOR ROLLING SURFACE TOPOGRAPHY OF STEEL PLATE AND METHOD FOR MANUFACTURING SAME

Abstract

A roll for rolling surface topography of a steel plate is disclosed. A plurality of raised textured points are arranged on a roll surface. The shape formed by a joint between each single textured point and the roll surface is circular or approximately circular. The circular shape has a diameter of 50150 m. Each single textured point has a raised height of 212 m, and the overlap among adjacent textured points is lower than 10%. The quantity variance of the textured points per square millimeter of the roll surface is lower than 20%, and the coverage area ratio of the textured points in each square millimeter is 3090%. The method comprises performing surface treatment on a feed roll to control the surface roughness Ra of the roll to be smaller than 0.5 m; and performing layer-by-layer ablation on a surface material of the roll to form the textured points.

Claims

1. A roll for rolling a surface topography of a steel plate, characterized in that a plurality of raised textured points are arranged on a roll surface; a shape formed by a joint between each single textured point and the roll surface is circular or approximately circular, and the circular shape has a diameter of 50150 m; the each single textured point has a raised height of 212 m, and the overlap among adjacent textured points is lower than 10%; and the quantity variance of the textured points per square millimeter of the roll surface is lower than 20%, and the coverage area ratio of the textured points in each square millimeter is 3090%.

2. The roll for rolling the surface topography of the steel plate according to claim 1, characterized in that bottom diameters of the raised textured points are not smaller than top diameters.

3. The roll for rolling the surface topography of the steel plate according to claim 1, characterized in that the overlap among adjacent textured points is lower than 5%.

4. The roll for rolling the surface topography of the steel plate according to claim 3, characterized in that the overlap among adjacent textured points is 0.

5. The roll for rolling the surface topography of the steel plate according to claim 1, characterized in that the quantity variance of the textured points per square millimeter of the roll surface is lower than 10%.

6. The roll for rolling the surface topography of the steel plate according to claim 5, characterized in that the quantity variance of the textured points per square millimeter of the roll surface is lower than 5%.

7. The roll for rolling the surface topography of the steel plate according to claim 1, characterized in that the coverage area ratio of the textured points in each square millimeter of the roll surface is 5080%.

8. The roll for rolling the surface topography of the steel plate according to claim 1, characterized in that the steel plate is a cold-rolled steel plate.

9. A method for manufacturing a roll for rolling the surface topography of the steel plate according to claim 1, characterized by comprising the following steps: (1) performing a surface treatment on a feed roll to control the surface roughness Ra of the roll to be smaller than 0.5 m; and (2) performing a layer-by-layer ablation on a surface material of the roll to form the textured points.

10. The method according to claim 9, characterized in that the layer-by-layer ablation on the surface material of the roll is performed by adopting an ultrashort pulse laser; and during ablation, the ultrashort pulse laser transverses translational movement along a generatrix of the feed roll, and wherein the feed roll is in a rotatable state after being driven.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] FIG. 1 shows a microcosmic topography of a surface of a roll in an embodiment 1.

[0029] FIG. 2 shows a microcosmic topography of a surface of a roll in an embodiment 2.

[0030] FIG. 3 shows a microcosmic topography of a surface of a roll in an embodiment 3.

[0031] FIG. 4 shows a device structure corresponding to a manufacturing method of the present invention.

[0032] FIG. 5 shows a surface manufacturing processing process corresponding to an embodiment 1, including 8 states/stages, i.e., 1)-8); wherein, in the FIG. 4, element 1 refers to a numerically-controlled machine, element 2 refers to a roll, and element 3 refers to an ultrashort pulse laser.

DETAILED DESCRIPTION OF THE INVENTION

[0033] Specific embodiments of the present invention are further described in detail below with reference to the drawings.

[0034] The present invention provides a roll with a special surface topography, and the surface topography of the roll has the following characteristics:

[0035] A great quantity of textured points are distributed on the surface;

[0036] Each textured point is nearly or approximately circular in shape and has a diameter of 50150 m;

[0037] Each textured point is of a raised structure and has a raised height of 212 m;

[0038] The overlap among adjacent textured points is lower than 10%;

[0039] The quantity variance of the textured points per square millimeter is lower than 20%; and

[0040] The coverage area ratio of the textured points in each square millimeter is 3090%.

[0041] Through a great deal of experimental researches, inventors discover that due to the textured points with the above-mentioned characteristics, the surface topography of the obtained roll has better topography copying ratio and low waviness.

[0042] Accordingly, another object of the present invention is to provide a method for manufacturing the roll with the special surface topography, and the roll with the above-mentioned technical characteristics can be obtained with the manufacturing method.

[0043] The method comprises the following steps:

[0044] (1) performing a grinding and polishing treatment on a roll, and cleaning a roll surface to enable surface roughness Ra of the roll to be smaller than 0.5 m and leave the surface to be free of oil stains;

[0045] (2) designing a surface topography of the roll having the above technical characteristics;

[0046] (3) driving the roll to rotate by using a numerically-controlled machine, and enabling an ultrashort pulse laser to do transverse translational movement along a generatrix of the roll; and

[0047] (4) controlling the ultrashort pulse laser to selectively perform a layer-by-layer ablation on a surface material of the roll based on the designed surface topography.

[0048] A roll with a special surface topography and a method for manufacturing the roll, disclosed by the present invention, are further explained and described below with reference to drawings and specific embodiments, however, explanations and descriptions do not improperly define a technical scheme of the present invention

Embodiments 1-3 and Comparative Examples 1-3

[0049] In the embodiments 1-3, a surface topography of a roll is subjected to refined designing and processing. The surface of the roll has a great deal of textured points, each textured point is approximately circular in shape, has a diameter of 50150 m, and is of a raised structure, the textured points have raised height difference of 212 m, the overlap among the textured points is lower than 10%, and the coverage area ratio of the textured points in a unit area range is 3090%. FIG. 1 through FIG. 3 shows the designed roll surface microcosmic morphologies.

[0050] Rolls in the embodiments 1-3 and the comparative examples 1-3 are tested according to a measurement standard ISO 4287:1997, wherein the filters are Gaussian filters, the sample length of roughness is 12.5 mm, the sample length of waviness is 40 mm, and a filtering interval is 0.8-8 mm. Then, the rolls are loaded into a hot-galvanizing leveler where materials of the same specification material quality are leveled up by using substantially identical process parameters under substantially identical working conditions. The ratios of surface roughness of leveled steel plates to roughness of rolls are measured and are taken as topography copying ratio indexes.

[0051] Specific designed parameters and measurement contrast results are shown in a table 1 as follows.

TABLE-US-00001 TABLE 1 Textured Topography point Raised Quantity Coverage copying diameter height Overlap variance area Roughness ratio Waviness Embodiment 1 100 m 8 m 0 0 62% 2.13 m 74% 0.56 m Embodiment 2 100 m 4 m 0 5% 56% 2.17 m 73% 0.63 m Embodiment 3 80 m 4 um 5% 5% 71% 2.08 m 78% 0.65 m Comparative 2.15 m 62% 0.75 m example 1 Comparative 2.09 m 64% 0.70 m example 2 Comparative 2.16 m 64% 0.73 m example 3

[0052] Since microscopic structures of surface topographies of rolls have affect on copying ratios and waviness of the surface topographies of the rolls, the surface topographies of the rolls in the embodiments 1-3 are designed and the rolls are processed by adopting the manufacturing method disclosed by the present invention, such that the rolls have the characteristics that the surfaces of the rolls have a great number of textured points, wherein each textured point is approximately circular in shape with a diameter of 50150 m and is of a raised structure. Also, the textured points have raised height difference of 212 m. The overlap among all the textured points is lower than 10%, and the coverage area ratio of the textured points in a unit area range is 3090%. While in the comparative examples 1-3, the conventional electro-discharge texturing process is adopted, therefore, the obtained ordinary roll surfaces do not have the above-mentioned characteristics. The topography copying ratios is relatively low and the waviness is relatively high.

[0053] Specific implementation procedures of the roll manufacturing method disclosed by the present invention are described below by taking the embodiment 1 as an example with reference to FIG. 1, FIG. 4 and FIG. 5:

[0054] (1) performing grinding polishing treatment on a roll, and cleaning a roll surface to enable surface roughness Ra of the roll to be smaller than 0.5 m and leave the surface to be free of oil stains;

[0055] (2) designing a surface microcosmic topography of the roll, referring to FIG. 1 specifically;

[0056] (3) referring to FIG. 4, driving the roll 2 to rotate by using a numerically-controlled machine 1, and enabling an ultrashort pulse laser 3 to do transverse translational movement along a generatrix of the roll 2; and

[0057] (4) controlling the ultrashort pulse laser to selectively perform a layer-by-layer ablation on a surface material of the roll based on the designed surface topography.

[0058] In the embodiment 1, a picosecond pulse laser with average power of 100 W is used. After the laser is focused, each pulse will ablate a material with the diameter of about 5 m and the depth of about 1 m in the roll surface. Therefore, the maximum raised height of the microcosmic topography according to the embodiment 1 is required to be processed in 8 layers. FIG. 5 shows a material processing process of one microcosmic area of the surface of a roll, and a material is removed layer by layer through an ultrashort pulse laser to obtain a final-required surface topography.

[0059] Note that, cited above are only specific embodiments of the present invention, apparently, the present invention is not limited to the above embodiments, at the same time, many similar variations are present. All transformations directly derived from or associated with contents disclosed in the present invention by those skilled in the art shall fall within the scope of protection of the present invention.