JPS61126944A - Production of blank clad material by insert-casting method - Google Patents

Abstract

PURPOSE:To produce efficiently blank clad materials having various clad widths at a high yield by juxtaposing plural sheets of the same or different kinds of core materials for cladding into a casting mold having a rectangular cross section along the long side walls of the casting mold and executing insert- casting. CONSTITUTION:Two sheets each of the core materials 5-8 each consisting of a stainless steel, nickel steel, high-carbon steel, etc. are juxtaposed along the long side walls in the casting mold 4 having the rectangular cross section. A release material 9 such as MgO is preferably coated on the surfaces facing said mold walls to permit the easy stripping of the cladding material and an antioxidant 10 such as hydrocarbon paint is coated on the surfaces facing the cladding material to attain the tighter unification with the cladding material. A molten metal is then poured into such mold 4 and is solidified integrally with the materials 5-8. Two pieces of the three-layered blank clad materials having the optional width are thus obtd. The cladding material on the outside of the materials 5-8 is stripped after blooming, by which the 3-layered clad billet is obtd.

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention is a method of manufacturing a cladding material by placing a core material in a mold using a holding means such as suspension, and casting the core material. It's about.

Here, cladding material refers to intermediate products such as Talarado slabs and cladding plumes before being hot-rolled in a hot strip mill.〇 (Conventional technology) As a method for producing cladding material by casting method As shown in Figure 2, stainless steel, high carbon steel or N
A method for obtaining clad material is to hold a solid core material made of I steel or the like suspended in a mold 2, and pour molten low carbon steel 3 around the core IK1 and solidify it. widely known.

The cladding material obtained by such a method is usually made into a steel billet by blooming rolling, and then the final product is processed (depending on the requirements for the cladding material product, the surface of the cladding billet is treated or the core material is treated). One side of low carbon steel, etc. that has been poured into the surrounding area and solidified (hereinafter referred to as coating material) is peeled off or a clad steel piece is divided in the storage direction.
After all of the above operations have been completed, the steel is hot rolled and plate rolled into a clad steel plate (including copper strips) that has a variety of properties such as corrosion resistance and mechanical strength.

The procedure for molding such a clad steel plate will be explained in more detail with reference to Fig. 3.The cast clad steel ingot (Fig. 3a) u is removed from the mold 2 and bloomed (Fig. 3b). After that, the &A and B portions indicated by diagonal lines in the figure are cut off to obtain a cladding material (C in the same figure). here B
The part can be relatively easily peeled off by applying MgO to the core material in advance, and the -10,000 A part can be cut using a gas cutting machine. The reason why such refinement is necessary is that if part B remains, there is a high risk that it will get stuck in the rolling roll in the next hot rolling process and damage the roll, and part A will wrap around the steel plate and scrape, damaging the shape of the edge of the plate. This is because it is highly dangerous. The clad material from which unnecessary parts have been removed is hot-rolled into a clad hot-rolled plate with a thickness of approximately 2 to 6 uI (d in the same figure), and then to a final plate thickness of 0.6 to 6 uI.
It is cold rolled to about 1.5 mm and becomes a product version.

(Problems to be Solved by the Invention) However, in the above-mentioned conventional method, when it is desired to vary the width of the cladding material, especially when it is desired to reduce the width of the cladding material, there are problems as described below. .

In other words, when changing the width of the cladding material, the conventional methods are as follows: 1) prepare a core material with a corresponding width;
Measures are taken to reduce the width of the clad billet by holding each core material suspended in a mold with a size that matches the width of the valley core material, or by reducing the width of the slab in the blooming process. I've been exposed to it.

However, method 1) requires a large number of molds depending on the width of the core material, which has the disadvantage of increasing mold management costs. With this method, there is a limit to how narrow the width of the clad steel pieces can be made, since not only does the manufacturing yield decrease, but also variations occur in the crimping conditions of the clad steel pieces.

In addition, to obtain cladding products with various widths, it is common to make cladding steel sheets and then slit them into the required width using a shear9. Although this seems like a good idea at first glance, there were problems such as work hardening of the slit portion created by the shearing machine and cracking of edges during subsequent cold rolling, resulting in a decrease in the yield of good products.

This invention was made in view of the above circumstances, and it is possible to easily change the width of the cladding material when producing the cladding material by the casting method, and to reduce the width of the material without causing the above-mentioned problems. (Means for solving the problem) The present invention aims to solve the problem in the unsteady deformation region, that is, as shown in FIG. At the point where both edges and both ends (
(not shown) although it is difficult to crimp the area near the
Since the steady deformation region indicated by n in the figure is easy to crimp and has little loss, the idea began with the idea that it would be better to make a plurality of clad materials in one mold.

That is, in manufacturing a cladding material by arranging a core material in a mold having a rectangular cross section and casting the core material around it, the present invention provides the following methods: This is a method for manufacturing a cladding material using a casting method, which involves arranging two or more core materials for cladding of the same or different types in parallel.

This invention not only makes it easy to change the width of the cladding material, but also allows for the production of a wide variety of cladding materials and the manufacturing cladding ratio tS.
It can be applied advantageously to various cases.

(effect) This invention will be specifically explained below.

FIG. 1A schematically shows how the clad core material is placed in the mold according to the present invention, and in the figure, number 4 is the mold, 5, 6, .
7 and 8 are stainless steel, and nickel fI4 and fc are core materials made of high carbon steel, etc. In this example, core materials 5, 6. The case where two of each are installed side by side is shown. Here, the surfaces of core materials 5°6.7 and 8 against the mold wall are as follows:
It is desirable to apply a release material 9 such as MgO.

This is because by doing so, after pouring the molten metal and rolling it after casting, the coating material adhering to the surface of the core materials 5 to 8 can be easily peeled off. be. In addition, on the side of the mold 4 where the core materials 5, 6 and 7.8 face each other, the molten metal (coating material) to be poured is placed so that the coating material to be poured is tightly integrated with the cores IK 5 to 8. ) Antioxidant 1 for hydrocarbon paints, etc. to prevent oxidation of
It is desirable to apply 0.

Now, as mentioned above, the core materials 5, 6 and 7, 8 are suspended,
When molten metal is poured into the disposed mold 4, the molten metal solidifies while being integrated with the core materials 5 to 8. Therefore, in one mold 4, two eight-layer cladding materials of arbitrary width are formed. This means that you will be able to obtain one. In addition, at this stage, core materials 5 to 8
Solidified metal is also adhered to the side facing the mold wall, and this solidified metal layer is peeled off after blooming to form a three-layer clad steel piece.

By the way, in the above method, the core materials 5, 6 and 7.
By carefully changing the width and thickness of 8 and changing the hanging position within the mold, the cladding material width and cladding ratio can be easily changed. 7.8, by using different types of steel materials, it is possible to obtain a three-layer Ranod #4 material with different components.

Furthermore, among the nine cores 5.6 and 7.8 arranged oppositely in the mold, for example, the core material 8 can be eliminated, and the core material 5,
If you place only 6 and 7, you can make 3 in the same mold.
It is also possible to simultaneously produce a layer-clad steel material and a double-layer clad steel material. Similarly, by eliminating the core material 6°8 from among the core materials 5 to 8, it is also possible to produce two types of two-layer ranod fI4 materials of any desired width using the same mold.

Furthermore, as shown in FIG. 1B, if the mold 4 is wide, by arranging the core materials 11 to 14 as shown in the figure, it is possible to make two layers of ranod steel fj in the same mold.
It is also possible to obtain two types of clad steel materials, one type of three-layer clad steel material, and a total of three types of clad steel materials with different widths and materials.

In addition, as shown in FIG. 1 O, the shape of the mold house may be a positive sign shape. However, in this case, the side that comes into contact with the rolling roll during blooming is the long side of the mold.

(Example) The mold is for casting a 23-ton steel ingot, specifically, the head section is 728 x] 728" and the bottom section is 784 x 1.
764 mm, mold height 2800" and average ingot thickness 75"
Using a 6" mold, a cladding material was produced by a casting method using a core material having the steel type and dimensions shown in Table 1 under the conditions of the following equipment as shown in FIG. 5a%c.

Next, the obtained cast clad steel ingot is made into a steel billet with a thickness of about 170 to 280 mm by blooming rolling,
After peeling off the surface of the steel billet or cleaning the surface of the steel billet, and dividing the width by gas-cutting all the parts without core material, and binding the desired clad steel billet, hot rolling is performed to form 2 to 6 pieces of steel.
8 to 1251m by rolling copper strips or thick plates
It was originally manufactured from steel plate.

It was confirmed that the cladding ratio of the Nenya clad steel sheet obtained in this way was always stable, and the yield of non-defective products was also confirmed to be extremely good.

The cladding evaluations of each cladding material in Examples 1 to 4 are also shown in Table 1. Here, in the cladding evaluation, it is known that the shear strength is satisfied if the inclusion area ratio at the cladding interface is 2% or less, so we judge the quality based on the inclusion area ratio at the interface: 2%. did.

As a result, as shown by the ◎ mark in the clothes, each example 1~
It was also found that all of the cladding materials obtained in Example 4 had an inclusion area ratio of 0.1% or less, and were extremely excellent as cladding materials.

Note that the distance between the core materials indicated by symbols in Figure 5 a, b, and C is preferably as short as possible from the viewpoint of yield, but in industrial scale production, the shortest distance is 404 mm, and usually about 60 to 70 mm. is good.

Next, using the same mold as described above, a cladding material was manufactured with the core material shown in Table 2 arranged as shown in Figure 1 above.

Then, it was finished into a clad material in the same manner as described above.

Each of the clad steel plates thus obtained had a stable cladding ratio, a good yield, and an inclusion area ratio of 2% or less.

In the case of Naori rad steel, ordinary steel such as low carbon aluminum killed steel is generally selected as the coating material, but if the application is special, high tensile steel (for example a: 0.05~o, oa%, In: 1.
2~1.8%, sl: 0.2~o, a%, balance Fe
etc.) are sometimes used.

(Effects of the Invention) Thus, according to the present invention, by appropriately combining various cladding widths according to the demands of customers, cladding materials of various widths according to the demands can be manufactured with a high yield using a small number of molds. be able to.

[Brief explanation of drawings]

FIGS. 1a, b, and C are all schematic diagrams showing preferred arrangement examples of core materials according to the present invention; FIG. 2 is a schematic diagram showing suspension and arrangement of core materials according to a conventional method; FIG. Figures a to d are explanatory diagrams of the manufacturing procedure of 5 clad steel plates according to the conventional method, Figure 4 is an explanatory diagram of plastic deformation behavior during blooming of the clad material, and Figures 5 a to C are examples of the examples. The following is a schematic diagram showing the arrangement of the core material.

Claims (1)

[Claims] 1. When manufacturing a cladding material by arranging a core material in a mold with a rectangular cross section and casting the core material, the same type of material is placed along at least one long mold wall in the mold. Alternatively, a method for manufacturing a cladding material by a casting method, which is characterized by arranging two or more core materials for cladding of different types in parallel.