JPH0446612A - Working method of work roll for dull finishing rolling and manufacture of dull finished stainless steel sheet - Google Patents

Abstract

PURPOSE:To offer a dull finished stainless steel sheet with antidazzle characteris tic resistance and color tone by performing shot blast using alumina grit as a projecting grain at the contact surface of roll with a material to be rolled and restraining the degree of gloss of the surface not more than a specified value. CONSTITUTION:After the surface which becomes a surface to be rolled of the work roll of a Sendzimir mill or the like is finished by grinding with a grinding wheel, the alumina grit is ejected upon the surface using a spray while the roll is revolved. The degree GS (20 deg.) of gloss to be obtained of the surface of roll is controlled <=80. A stainless steel strip is rolled at the draft of >=2% using the dull worked work roll and the dull finished stainless steel strip of which the degree GS (20 deg.) of gloss of the surface after rolling is <= about 100 is manufactured. Because the stainless steel strip is rolled using the roll with glossless surface which is obtained by shot-blasting alumina grit, antidazzle characteristic can be remarkably improved.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a method for processing work rolls for dull finish rolling used in the production of stainless steel sheets with excellent anti-glare properties useful as materials such as building materials, and anti-glare. The present invention relates to a method for manufacturing stainless steel sheets with excellent properties.

<Conventional technology> Recently, stainless steel plates have been widely used as building materials, etc., and the conventional JIS G4307 and G43
The finishing types shown in 05 are not sufficient to meet the needs, and the demand for stainless steel sheets with new surface finishes has emerged. An example of this is dull finish stainless steel plate. This is a stainless steel with a dull finish that has a much lower gloss than the 2D finish specified in the JIS standard, and is required to have anti-glare properties even when used for the exterior and interior of buildings. .

In order to meet this requirement, there is a known method of finishing stainless steel plates by rolling them using rolling work rolls that have been finished by projecting iron balls or iron grids.

Furthermore, as disclosed in Japanese Patent Application Laid-Open No. 63-168206, it is known to process a rolling work roll into a satin-like semi-gloss surface by subjecting it to electrical or chemical treatment.

Further, JP-A-63-49305 discloses a method of imparting anti-glare properties by roughening the surface roughness R2 of the work roll to 10 to 30 μm.

<Problems to be Solved by the Invention> However, in the above-mentioned roll processing method in which shot blasting is performed using iron balls or iron grids, in the case of hard work rolls such as those used for rolling stainless steel, contact between the work roll and the material to be rolled may occur. As a practical matter, it is impossible to shot blast the entire surface completely, so even if you roll using such work rolls, some parts will be almost matte, but the rest will have the luster of the stainless steel material. Only a so-called semi-gloss surface can be obtained.

In addition, the method disclosed in JP-A No. 63-168206 involves chemically corroding the work roll by immersing it in an oxidizing solution or the like.
Alternatively, corrosion is accompanied by electrolytic treatment, but with this method, the roll surface tends to develop rust after corrosion, requires a lot of effort to store the roll, and has problems due to the reflectance of light on the rolled plate surface. However, there are disadvantages in that non-uniform patterns are likely to occur, and waste liquid treatment is problematic in terms of pollution.

Furthermore, the method disclosed in JP-A-63-49305 obtains anti-glare properties by increasing the surface roughness R2 of the work roll;
There is a problem that even if 2 is increased, anti-glare properties cannot be obtained.

An object of the present invention is to provide a technology for producing a dull finish stainless steel sheet having unprecedented anti-glare properties and color tone, which solves the problems of the prior art.

<Means for Solving the Problems> The present invention provides a method for dulling work rolls for rolling, in which shot blasting using alumina grid as blast particles is applied to the contact surface of the roll with the material to be rolled, and the gloss level of the surface is improved. G
This is a method for processing rolls for dull finish rolling, characterized by suppressing s (20°) to 80 or less.

Further, a dull finish is obtained by rolling a stainless steel strip at a rolling reduction rate of 2% or more using the work roll subjected to the dull processing, and the glossiness GS (20") of the plate surface after rolling is 100 or less. This is a method for manufacturing stainless steel sheets.

<Function> As a result of various studies conducted by the present inventors, it was found that surface roughness and anti-glare properties do not necessarily match. In other words, the reflection of light is not significantly affected by large undulations on the material surface, but rather depends on the microscopic features within the large undulations, and these microscopic roughnesses are called surface roughness. Display R
It turns out that it is not reflected much in 2 and R1. As a result of further research, they discovered that the reflectance of light can be effectively suppressed by applying shot blasting using alumina grids as projection particles even on very hard materials, and completed the present invention.

According to the present invention, since the roll surface is processed by projecting an alumina grid, even a hard roll can be easily ground due to the high grindability of alumina, and the roll surface gloss level as (20°) can be achieved in a short time. is finished below 80. When rolling using this processing roll, by setting the rolling reduction ratio to 2% or more, the roll roughness can be improved (
It is sufficiently transferred to the surface of the stainless steel plate, and the gloss level Gs (20°) of the stainless steel plate surface is 100 or less.
A product with excellent anti-glare properties and a unique color tone can be obtained.

At this time, if the glossiness of the roll exceeds 80, it will not be possible to obtain a stainless steel sheet with a glossiness of 100 or less, which is necessary for anti-glare properties, even if the rolling reduction is increased; on the other hand, even if the glossiness of the roll is 80 or less, the rolling reduction will If it is less than 2%, the matte roll surface will not be transferred sufficiently and only a surface with higher gloss than necessary will be obtained, leaving problems in terms of anti-glare properties.

<Example> Examples of the present invention will be described below.

Example 1 Work roll outer diameter 50wImφ for Sendzimer rolling mill,
After finishing the surface to be rolled with a length of 1400 (Foundation) to a gloss level of GS (20°) of 200 by polishing with a grindstone, an alumina grid was sprayed onto the surface using a sprayer while rotating the same roll.

The spraying conditions were as follows.

Distance between nozzle tip and roll surface: 11 h 100 ms Roll rotation speed: 10 rotations/plate]n Projected particles: #36 alumina spraying speed: 30 m/sec Spraying amount: 1.5 f/win The resulting roll surface The glossiness Gs (20°) was measured and found to be 45.

Then, by this dull roll, J r SG4305
and 5US304 with 2D finish as specified in G4307.
, a steel strip with a thickness of 1.6m+ is rolled into a thickness of 1.5m by one bus rolling.
It was finished to m+ (rolling reduction rate of about 6%). The dull finish stainless steel sheet obtained in this way has a gloss level of Gs (20°
) is 50, whereas that of conventional dull finish materials is about 200, while the gloss is significantly suppressed,
It had a solid appearance with a unique color tone.

Example 2 5US with 1 finish specified in JIS (1; 4304)
304, a copper strip with a thickness of 4.0 mm was rolled using a Sendzimer rolling mill for 7 passes to reduce the thickness to 1.6 m, and then rolled for 1 pass using the dull finishing roll shown in Example I. The plate was rolled to a thickness of 1.5 m. Thereafter, solution treatment was performed in a BA (bright annealing) or AP (annealing and pickling) line to obtain a dull finish stainless steel strip. Glossiness GS of the obtained steel strip
(20°) was 50 when passing through the AP line and 60 when passing through the BA line, which were values that passed the anti-glare property.

<Effects of the Invention> In the present invention, since rolling is performed using a roll having a matte surface obtained by shot blasting an alumina grid, anti-glare properties can be significantly improved.

In addition, due to its unique color tone, when used for interior and exterior materials of buildings, it gives a dignified and dignified appearance.According to the present invention, dull finish stainless steel sheets can be stably produced at a relatively low cost, making it suitable for industrial use. Brings great effects.

Patent applicant: Kawasaki Steel Corporation

Claims (2)

[Claims] (1) In a method for dulling work rolls for rolling, shot blasting using alumina grid as projection particles is applied to the contact surface of the roll with the material to be rolled, and the gloss level of the surface is G_S.
A method for processing rolls for dull finish rolling, characterized by suppressing the angle (20°) to 80 or less. (2) A stainless steel strip is rolled at a reduction rate of 2% or more using the dull-processed work roll of claim (1), and the glossiness G_S (20°) of the plate surface after rolling is 100 or less. A method for manufacturing a dull finish stainless steel sheet characterized by: