JPS61249647A - Mold for continuous casting - Google Patents

Abstract

PURPOSE:To extend the life of a casting mold by joining a stainless steel, etc. to the surface of a casting mold body and forming superposedly a composite plating layer dispersed therein with pulverous particles having wear resistance or self-lubricity and a hard Cr plating layer on the surface thereof. CONSTITUTION:A stainless steel or casting having wear resistance is joined by a diffusion welding method, etc. on the surface of a base body 1 for the casting mold consisting of a copper alloy, etc. to form the 1st layer 2 thereon. The composite plating layer 3 consisting of an Ni-P electroplating film as the matrix and dispersed therein with the pulverous hard particles or pulverous particles having the self-lubricity is formed on the 1st layer 2 by electrodeposition. The hard Cr plating layer 4 is formed on the surface of the 2nd layer 3 to constitute the casting mold. The 1st layer 2 is joined onto the base body 1 and the layer 3 is the electrodeposited plating layer having the substantial thickness and therefore the life of the casting mold is extended.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a mold for continuous casting, and particularly to a mold having excellent wear resistance.

(Prior Art) Many methods are currently being used to prevent wear on the inner surface of continuous casting. A representative example of the conventional method will be described below.

Figure 2 shows a first layer of N1 or 00 layer 2, a second layer of N1 or 00 layer 2,
N1-P or N i -B or 0o-P as a layer
Or 00-B plating layer 3, Cr plating layer 4 as the third layer
It is a continuous casting mold formed by forming (%Koshō 52-5
(See No. 0734).

In molds made by this method, there is a limit to the thickness of the first N1 or 00 plating layer, and it is soft. (2) The thickness of both the second and third layers is Plating is not possible. (3) When multi-layer plating is performed, thermal stress during operation tends to cause crevices between the layers. As a result of the above, peeling and abrasion phenomena occur, which has the disadvantage of not being durable for long-term use. .

Further, FIG. 3 shows that a N1 plating layer 2f is formed as a first layer on the surface of a copper or copper alloy base 10 forming the mold body, and a N1-W or Pa-0ot- matrix is formed on the surface of the N1 plating layer 2f. This is a continuous casting mold comprising a plating layer 3 in which wear-resistant particles and self-lubricating fine particles are dispersed and eutectoid. (Japanese Patent Application No. 55-105425) The ML-W, We-Oo alloy plating film, which is the second layer matrix, produced by this method and made by Yutsuri has a large precipitation stress, and therefore thick plating is impossible. Furthermore, since the first N1 plating layer has a low roughness of 0 or more, there is a problem in terms of wear resistance, and it is not expected to extend the service life much.

Typical examples have been described above, and although various other measures have been taken to extend the lifespan, the current situation is that it is difficult to manufacture the desired molds.

(Problems to be Solved by the Invention) In view of the above-mentioned current situation, the present invention aims to provide a continuous casting mold with excellent wear resistance.

(Elaborate means to solve the problem) That is, the present invention joins stainless steel or a cast metal with excellent wear resistance to the surface of copper or copper alloy, and forms an N1-P electroplated coating on this surface as a matrix. This mold for continuous casting is formed by forming a composite plating layer in which hard fine particles or self-lubricating fine particles are dispersed in the coating, and further forming a hard Cr plating layer on the outermost layer.

An embodiment of the present invention will be described below with reference to FIG.

On the surface of the copper or copper alloy that is the base 1 forming the mold body, and below the meniscus position, stainless steel,
A first layer 2t is formed by joining N1 alloy or a cast material with excellent wear resistance by diffusion welding or explosion bonding. A second layer 3't- is formed on this surface by composite plating in which the N1-I' electroplating II film is used as a matrix and hard fine particles are dispersed in the film. Furthermore, hard C on the outermost surface
r A mold for continuous casting in which a plating layer 4 is formed.

The structure of the present invention, including the above-mentioned embodiments, will be explained in detail below.Substrate 1: Copper or copper alloy, which has been conventionally used in terms of thermal conductivity, may be used, and the material is not particularly limited.- First layer 2: Heat Resistance 9 From the viewpoint of strength, high-grade stainless steels such as 250R-25Ni precipitation hardening temperature stainless steels or N1 alloys such as Hastelloy are commonly used. It is also possible to use cast steel or the like. Next, regarding the method of joining this first layer, diffusion welding is most preferable since it is necessary to join the entire surface to be joined. According to this method, the base 1 and the first layer 2 are metallurgically bonded to each other to obtain strong adhesive strength, and also have good heat conduction and a large cooling effect. Regarding the thickness of the tX first layer 3, it is better to make it as thick as possible in consideration of repair and reuse, but in general, several millimeters to several millimeters are often adopted.

Note that an explosion bonding method may be used instead of diffusion welding.

2nd layer 3: For dispersion composite plating, the matrix coating material is generally t-Ni electrodeposition, 1ii-P or N1-
B 2 O electroless plating is often used, and many particles such as various oxides, carbides, sl compounds, and self-lubricants are used as the dispersed particles. However, N1 electrodeposition, which serves as the matrix, has low roughness and therefore has poor wear resistance. In the case of N1-P or N1-B electroless metal, (1) thick plating is difficult, and (2) when dispersing particles, the bath lacks stability and at the same time cannot be adequately controlled. (3) Workability is poor due to high bath temperature. However, the N1-P plating adopted in the present invention is an electrodeposition method, which solves all of the above problems and has the advantage that the desired roughness can be obtained with the plating as it is. have.

Fifth layer 4: This Cr plating is performed for the purpose of preventing droplet adhesion at the initial stage of use, and may be a commonly used plating.

Also, the thickness is not particularly limited (LO5~cL
I think 11111 is economical.

The NZ mold manufactured as described above has excellent properties against wear and can extend its lifespan, which has been confirmed by actual experiments and actual machine usage results.

Here, we will discuss the differences in performance and functionality between the mold of the present invention and the conventional mold (
(effects, effects).

(1) Since a material harder than steel or copper alloy is bonded under the dispersed composite plating, the mold base will not be damaged suddenly even if the plating film peels off or wears out. In addition, if the plating value J[K is peeled off or worn out, it can be easily repaired by lightly polishing the surface of the lower mounting device and re-plating.

(2) Conventionally, soft N1 was used in the dispersed composite plating layer.
Electroless plating such as 1ii-P or ML-B was difficult to electrodeposit or thickly plate, but the present invention provides N1-
Since it is a P-plated film, there are no particular restrictions on the plating thickness, and the mold can be designed freely taking into consideration the lifespan, resulting in a longer lifespan.

Example 1 N1 electrodeposition, N1-P electroless plating, N1-P electroless + Az2on dispersion plating, N1-P electrodeposition and N1
-P electrodeposition + AL, os Dispersion plating machine, friction surface pressure 50 K9f/cr1. Friction speed IIQ 5m/eea% As a result of performing a wear test in a non-lubricated state, as shown in Fig. 4, the plating am of the present invention was superior.
Example 2 The mold of the present invention was applied to a continuous casting mold (for a plume with a width of 480 mm and a length of 800 mm), and a steel alloy was used as the base material. A first layer of precipitation-hardened stainless steel (17cm
-4pH) t-diffusion welding, and then a second layer of dispersed composite plating layer of N1-P + alumina with an average grain size of 10 μm was formed by electrodeposition to a thickness of 100 μm. Furthermore, the outermost layer was coated with 50 μm of hard Cr plating.90 This mold was installed in an actual continuous casting machine and its performance was evaluated.
2wm5 electrodeposition and 100μm N1-P electroless plating
In the mold that was finally hard Cr plated f: 5 Q pm, the copper alloy of the base was exposed after 200 charges of casting. Most of the layers remained, and even where some parts were worn out, they were bonded and the stainless steel was in a condition that was sufficiently durable for use.

Example 3 A high chromium cast steel plate with a thickness of 1.5 μm was diffusion welded to the same mold as in Example 2, and N1-P + average grain size of 5 μm was formed by electrodeposition.
1 composite plating layer with m chromium carbide particles dispersed in it.
A thickness of 00 μm was provided. Furthermore, hard Cr plating Is on the outermost layer
Oμm implementation friend.

The performance of this casting mt-mounted on an actual continuous casting machine was evaluated and the results showed that the surface of the conventional mold, that is, the copper alloy base, was
-The mold was composite plated with aluminum dispersed in the P electroless plating film, and finally hard Cr plated to a thickness of 50 μm.
After 350 charges of casting, the copper alloy of the base was exposed and the damage was severe.
After the charge casting, most of the plating layer remained as in Example 2, and some of the underlying high chromium cast steel was exposed, but only a few scratches were observed and the product was in a state that was sufficiently durable for use.

As described above, it has been confirmed that the mold manufactured by the present invention has a stable and long service life compared to molds manufactured by the conventional method due to its excellent wear resistance, which improves the autonomy of the mold. , the quality is the same, and the industrial value is great.

[Brief explanation of the drawing]

Fig. 1 shows an embodiment of the structure of the continuous casting mold of the present invention, Figs. 2 and 3 show the structure of the conventional same mold, and Fig. 4 shows the effects of the continuous casting mold of the present invention. This is a graph showing. Sub-Agents 1) Meifuku Agent Ryo Hagiwara - Figure 4

Claims (1)

[Claims] A composite in which stainless steel or a cast metal with excellent wear resistance is bonded to the surface of copper or copper alloy, and a Ni-P electroplated coating is used as a matrix on this surface, and hard particles or self-lubricating particles are dispersed in the coating. A continuous casting mold formed by forming a plating layer and further forming a hard Cr plating layer on the outermost layer.