JPS61266164A - Continuous casting method for clad ingot - Google Patents

Abstract

PURPOSE:To produce easily and continuously a clad ingot by joining the side faces of the ingots drawn from juxtaposed continuous casting devices to each other in the mid-way and remelting the joint part by arc welding, etc. to form a deposited metal part in the joint part. CONSTITUTION:Molten steels A, B consisting of different materials are supplied to the juxtaposed continuous casting devices 10, 11 and the ingots 12, 13 are drawn to a curved shape by pinch rolls 14 to join the side faces of the ingots 12, 13 to each other in the mid-way of drawing. The side face parts 12a, 13a of the ingots 12, 13 are remelted by an arc welding machine 15 in the joint position and a molten pool 16 and floating slag 23 are formed. The joined ingots 12, 13 are press-welded by rolling rolls 14a and the clad ingot 18 having the deposited metal layer 17 consisting of the different material is obtd. The continuous production of the clad ingot having high productivity is thus made possible.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a clad slab in which the side surfaces of two slabs are joined together by overlay welding such as arc welding, and clad slabs are continuously cast. The present invention relates to a continuous casting method.

[Conventional technology]

BACKGROUND OF THE INVENTION Composite clad metal materials in which one metal is entirely coated with another metal and the interfaces thereof are metallurgically bonded are known. Here, the metal to be covered is called the base material, and the metal to be covered is called the coating material. Conventional methods for manufacturing such Rud metal materials include applying a coating material to the base material under vacuum conditions and hot rolling it to make it adhere, and applying the coating material to the base material by various types of overlay welding. There are methods such as overlay welding, in which the base material is welded to the base metal, and a casting method, in which the base material is placed in a mold and a molten covering material is injected between the mold and the base material.

However, in all of these methods, a clad metal material is obtained by joining a coating material to a single base material, and continuous production is not possible. As a result, productivity is significantly lower,
Another drawback was that the yield was low.

Therefore, in the past, techniques such as those described in Japanese Patent Application Laid-Open No. 48-40634 have been developed to manufacture clad metal materials by continuous casting. As shown in FIG. 3, the technology described in the publication forms a weir 2 inside a mold 1,
Molten m3a for the base material is supplied into the weir 2, and melt m3b for the coating material is supplied between the weir 2 and the inner surface of the mold.

Then, the molten steel 3b for the coating material is cooled by the mold 1 and begins to solidify, and when the solidified shell 4a has grown to a predetermined thickness, the molten steel 3a for the base material is joined to this solidified shell 4a, and from then on, the molten steel 3a for the base material is Only the molten steel 3a is solidified.

In other words, the continuous casting technology for clad metal materials described in the above-mentioned publication is such that molten steel 3a of different materials is poured into the same mold 1,
3b, and these are cast integrally and simultaneously.

[Problems to be solved by the present invention]

However, in the conventional manufacturing technology of clad metal materials by continuous casting, there is a risk that the molten steel 3a for the base material and the molten steel 3b for the coating material may mix depending on the level of the molten steel 3a for the base material. Ta. In other words, if the level of the base metal molten steel 3a is at a position where the gap between the solidified shell 4a and the weir 2 is equal to or greater than a predetermined value, the area where the remelted steel 3a, 3b can mix becomes wider, and the coating The molten steel 3b for the base material is the molten steel 1i3a for the base metal.
Sometimes it got mixed into.

Therefore, in this conventional example, by controlling the flow rate and casting speed of the F6 steel 3a for the base material and the molten steel 3b for the coating material, the total flow rate of both molten steel 3a and 3b is controlled, and the molten steel 3a for the base material is molten. Adjusting the surface level. Both molten steel 3a, 3b
To adjust the flow rate, specifically, the stopper 5 or the like is used to control the injection amount of the base metal molten steel 3a, and as a result, the total flow rate with the coating material molten steel 3b is adjusted.

However, in such an adjustment method, if the control factors of the flow rate and casting speed of the base metal molten steel 3a and the cladding material molten steel 3b are out of order, the thickness of the solidified shell 4a will fluctuate, and the clad metal material of constant quality will be affected. I couldn't get it. Further, there was a drawback that the interface between the base material molten w13a and the coating material molten steel 3b was unclear. Furthermore, the thickness of the solidified shell 4a is the same as that of the molten steel 3a,
It has the disadvantage that it is affected by the type of mold 3b, the size of the mold 1, the size of the weir 2, etc., and cannot respond to changes in materials.

In the field of non-ferrous metal manufacturing, which produces Cu alloy materials, etc., conventional technology has been used to obtain cladding materials by installing two continuous casting machines in parallel and rolling or press-welding the cast hot slabs with rolls. being developed.

However, when this technology is applied to steel, there is a drawback that the surface of the slab undergoes oxidation under high temperature conditions, and the oxides inhibit interface bonding and cause interfacial delamination between dissimilar materials. I couldn't do it.

The present invention has been made to improve and eliminate the above-mentioned drawbacks of the conventional method, and it is an object of the present invention to provide a method for continuously manufacturing clad slabs using simple equipment and a uniform method.

[Means for solving problems]

The means for solving the problems of the present invention is to install devices that continuously produce slabs in parallel, and to join the slabs drawn from each device sideways in the middle, and to connect the joints by arc welding or the like. By remelting, a welded metal layer is formed at the joint, and clad slabs are continuously manufactured.

[For production]

Slab 1 cast from parallel continuous casting equipment 10.11
2. The slab 13 is guided in a curved manner by pinch rolls 14, and its side surfaces 12a and 13a are joined together.

A welding machine 15 for arc welding or the like is disposed at this position, and the welding machine 15 melts the joint surface of the revisit piece 12.13, forming a molten pool 1 in which molten steel of different materials is mixed.
form 6. Then, revisit one side 12a.

The oxidized scale 13a floats to the upper surface of the molten pool 16 as slag 23 and is separated from the molten steel. From this state, the revisited pieces 12.13 are rolled (pressed) by the pressure roll 14a on the downstream side, and a weld metal film 17 of a different material is formed between the revisited pieces 12.13. That is,
A clad slab with weld metal N17 formed between side surfaces 12a and 13a of slabs 12 and 13 made of different materials.
□18 can be cast, and continuous casting is possible.

The method of the present invention will be explained below based on the embodiments shown in the drawings.

〔Example〕

FIG. 1 is a schematic diagram showing the main parts of continuous casting equipment to which the method of the present invention is applied. As shown in the figure, in this embodiment, a continuous casting apparatus 10.
11 are installed side by side. The molten steel supplied to each continuous casting device 10.11 is of different materials. In the following, for convenience of explanation, the molten steel supplied to the continuous casting apparatus 10 (one time is 8 and the molten steel supplied to the continuous casting apparatus 11 is assumed to be B. , a holding roll and a pinch roll 14 are arranged, and each mold 19.19
Side surface 12a of slab 12.13 cast by 1
3a are guided to join each other. This revisit piece 12.
A welding machine 15 such as an arc welding machine or an electroslag welding machine is arranged at the joining position 13. 15a is
A plurality of electrode wires are provided for welding, depending on the width of the joint surface of the slab. Also, the molten pool 16
On both sides (in the direction perpendicular to the paper in Figure 1),
As shown in FIG. 2, a weir 21 made of refractory material, ceramic steel, water-cooled copper plate, etc. is installed with a spring 22 or hydraulic It is energized by etc.

Next, the operation mode of this equipment configured as above will be explained.

First, slab 1 of A steel cast from mold 10.11
The slabs 13 of steel No. 2 and B are pulled out while being guided by holding rolls and pinch rolls 14, and the slabs 13 of steel B are pulled out while being guided by holding rolls and pinch rolls 14,
The joining point between 13a is reached. For example, in an electroslag welding machine, power is supplied from the electrode wire 15a to the slag 23, and the electrode wire 15a and a part of the slab 12.13 are melted by the resistance heat flowing through the slag 23, and the molten pool 16 form.

In this case, the slab 12.13 is placed in the mold 19.
It undergoes oxidation between the point 19 and the joint point, and oxide scale is generated on the surface. However, this oxide scale floats up as impurities in the molten pool I6,
Since the slag 23 becomes slag 23, it does not cause separation of the joint interface between the slabs 12 and 13. Therefore, the molten pool 16 is
IM, Bli, and the electrode wire 15 exhibit the composition of C steel, which is a melt-mixed mixture.

The revisit piece 12.13 receives the pressing force of the pressing roll 14a,
They are joined by molten C steel. A welded metal layer 17 of C steel component is then formed at the bonding interface to form a clad slab 18. In other words, continuous casting of the clad slab 18 is possible.

Table 1 below shows the results of an experiment comparing the strength and condition of each joint surface between the clad slab 18 manufactured according to this example and the clad slab manufactured using the conventional technology used in the non-ferrous manufacturing field. It shows. The conventional technology referred to here is one in which two continuous casting machines are installed in parallel, and each slab is simply pressure-welded to form a clad slab. Further, in Table 1, A steel and 1361 refer to the steel type of the slab 12 in the case of the present invention, and Bll refers to the steel type of the slab 13 in the same figure. Further, in the case of the prior art, A steel is the steel type for the base material, and Bm is the steel type for the coating material.

(Continued from next page to margin below) According to Table 1 above, in the case of clad slab 18 produced by applying the method of the present invention, the strength of the joint interface between dissimilar slabs is excellent, and the metallurgical A good connection is obtained. In contrast, in the conventional technology, interfacial peeling occurs in all test materials. From this result, it is clear how superior the method of the present invention is.

By the way, the present invention is not limited to the above-described embodiments, and can be modified as appropriate. For example, the welding may be a normal arc welding method, an arc melting method, or another welding method. When using the arc melting method, appropriate powder, small grains, etc. of ferroalloy are added to the molten pool 16 to improve the affinity of the revisited pieces 12 and 13.
It17 may also be formed.

〔Effect of the invention〕

As explained above, according to the present invention, continuous casting of clad slabs with excellent productivity is easily possible. Furthermore, it has excellent bonding strength between cast slabs of different types, and can be used in a wide range of applications.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical cross-sectional view showing the main parts of continuous casting equipment made using the method of the present invention, FIG. 2 is a vertical cross-sectional view showing a weir for preventing leakage of the side part of the molten pool in the same equipment, FIG. 3 is a longitudinal sectional view showing the main parts of a conventional continuous casting facility. 12, 13... Slab 10.11... Continuous casting device 12a, 13a... Slab side 17... Welded metal layer 18... Clad Slab patent applicant Sumitomo Metal Industries Co., Ltd. Agent Man
Patent Attorney Toshihiko Uchida Figure 1 Figure 2

Claims (1)

[Claims] 1. Equipment that continuously manufactures slabs is installed side by side, and the slabs drawn from each equipment are side-joined in the middle, and the joined parts are remelted by arc welding etc. to form a welded metal layer on the joined parts. A continuous casting method for a clad slab, characterized in that a clad slab is continuously produced by forming a clad slab.