JPS5954446A - Casting mold for continuous casting and its production - Google Patents

Abstract

PURPOSE:To improve the adhesive strength of a surface coating layer and the seizure characteristic of a solidified shell by mounting a Cr layer via a specific intermediate layer on the inside surface of a casting mold, subjecting the same to a prescribed heat treatment and forming Cr carbide on the uppermost layer thereof. CONSTITUTION:An undercoating material of Ni and an Ni alloy, a melt sprayed layer of an Ni-base self-fluxing alloy, and a Cr layer are successively mounted in a laminar form on the inside surface of a casting mold made of Cu or a Cu alloy. The above-mentioned melt sprayed layer is remelted and the entire part of the Cr layer is brought into reaction with the carbon contained in the melt sprayed layer and is heated and held at and for the temp. and time necessary for the formation of Cr carbide. The Cr carbide is thus formed on the uppermost layer and the casting mold having the surface coating wherein the entire part is securely adhered by the diffusion among the layers is produced. This method is adapted also to a casting mold having the coating layers made successively thicker from the upper part of the mold toward the lower part and is applied not only the inside surface but also the lateral surface of the mold.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a 1-hole mold for continuous casting that is highly durable and does not cause burnout, and its features! ! The manufacturing method is 1441-4.

Continuous-no? The mold for manufacturing is usually made of the same or 0 gold, which has high thermal conductivity. Extremely heat-resistant and wear-resistant material is used in the mold body.
However, there are still many problems in terms of the adhesion of these surface coating layers and the problem of solidified shells. Particularly recently, during operation, the solidified shell in the culm breaks the mold paratha film used to provide lubricity and comes into direct contact with the inner surface of the mold. The so-called restraint breakout, which occurs as a result of seizing and rupture of the solid seal portion, has become a serious problem.

This restrictive breakout is mainly caused by seizure of the solidified shell due to insufficient supply of mold powder.The first objective of the present invention is to eliminate this cause by providing a mold that is highly wear resistant. The gist is that an IJV undercoat material made of nickel or nickel alloy is applied on the inner surface of a mold body made of copper or a compatible alloy,
Nickel-based self-fusing alloy thermal spraying IP on the same undercoat material
1 was coated with 14+t, and chromium carbide IF was added on the same sprayed layer.
It is a continuous image tI Zokawa type 1, which is characterized by the fact that the first sign is +, and the method for manufacturing such a mold is...
ib< is a copper alloy! On the inner surface of the 1ill M-type main body, a second Kel-base self-fusing alloy sprayed layer is attached to the undercoat material made of nickel or nickel alloy, and a chromium layer is further attached to the upper surface of the sprayed layer, and then the above-mentioned When the sprayed layer is remelted, all of the chromium layer is reacted with the carbon contained in the sprayed layer to form a carbonaceous material. This is the manufacturing method of the IJi type for continuous 197 lodgings.

In order to prevent such separation of the coating layer, the surface coating layer may be extended not only to the inner surface of the mold body but also to part or all of the side surfaces. In particular, in the case of a mold that is held between a pair of opposing long-side molds and used as a short-side mold with a width TτJ variation, both surfaces are in contact with the Jq-side molds. Transfer IVIIJ-t! Since it can be tightened, it has wear resistance! It is also a piece from the meaning of the word.

Wooden, Ming is fi) A mold with a chromium carbide layer on the top surface that has excellent resistance to firing and Ifl against molten steel and 111F solid dieno 1, and is highly wear resistant, and the chromium carbide r#l The major feature of this method is that it utilizes the low f6 carbon contained in the nickel-based self-fluxing alloy that flows into the base, and causes a carbonization reaction between it and the chromium layer of the upper tUt. This will be explained in detail with reference to the drawings below. The inner surface of the mold body (0) 1 μζ is shown in the figure, but first, the inner surface of the mold body (1) is filled with an intercoat material (2) made of near gel or nickel alloy. a joOlt m
Attach L at A. In this case, if a precipitation hardening copper alloy such as copper, ζζ chromium-copper, zirconium-copper, or beryllium-copper is used for the mold body (1), the strength will be increased by J=゛.

Next, dehydrogenation treatment is performed by heating, usually at 300 to 400° C. for one hour or more, to form a nickel-based self-fusing alloy sprayed layer with a thickness of 02 to 07 mm on the upper surface of the undercoat material (2). Next, 5 to 50 μrn Ff of chromium JP+ is attached to the upper surface of the self-fusing ('1 alloy thermal sprayed layer (6)) and heated and held at approximately 800 to 11 UO℃ for 1 to 6 hours. Chromium, which has a large affinity for carbon Z2, undergoes a carbonization reaction with the carbon contained in the self-fusing alloy, converting the chromium layer into a carbonized layer (4). Chromium carbide of 15.20 and 571 tm was formed when the material, RC radiation layer and chromium layer were kept in the atmosphere for 1.3 and 6 hours, respectively, at 1 (J) temperature. The mold obtained in the following manner is shown in Figure 1. If we take the layer PJ from the upper part of the mold to the lower part of the mold, the second
The one shown in the figure is ``4'', and the Nilagel-based self-fusing alloy sprayed layer (3) and the chromium layer are also 4! , if the primary layer thickness is increased by one layer from one part of the hook to the bottom, one as shown in FIG. 6 can be obtained. What is shown in Figure 2 and 5 rYI is the mold, and J) is the surface coating on the second part! Enrikiso υ
1 has good thermal conductivity and large heat removal property, and the lower part has high burn resistance and opening/closing fillability, and continuous Q.
It matches the properties required for casting.

As mentioned above, nickel-based self-fusing alloy thermal spraying 1t η(3)
In addition to improving the wear resistance of the mold as the base 11 itself, it also has the important role of causing a carbonization reaction with the 1+ carbon contained therein and the upper j11+ chromium.
Carbon is an essential component as the R4 component, and the compositions shown in the table below are usually used.

Here, to explain in more detail the heat treatment after applying the above-mentioned chromium layer and the effect of the pretreatment Jlllllr, in this pretreatment Jlllllr, chromium undergoes a carbonization reaction to form chromium carbide (4) ( In addition to 411, (a) the sprayed layer is melted and the sprayed particles are firmly and firmly bonded to each other, and the pore sealing process is performed. (b) Diffusion between the adjacent surfaces of each surface coating layer, including the mold body and undercoat material, forms a similar diffusion layer, which causes the first whole to adhere firmly to each other, and When the mold body is made of a precipitation-hardening copper alloy, solution treatment can be performed by I+ in combination with subsequent rapid cooling. Note that the quenching here refers to quenching of C for such precipitation hardening type alloys, and since these copper alloys are made of heat conductive material and have good Uf, they can be sufficiently quenched by ordinary air cooling. If a precipitation hardening copper alloy is used for the mold body, water cooling, oil cooling, or air cooling may be used as appropriate.
? It goes without saying that after quenching the material, an aging heat treatment is performed at a temperature and time depending on the components.

In addition, this heat treatment (4) is carried out in a vacuum or in an inert gas to prevent chromium from oxidizing during the heat treatment.
f) It is preferable to carry out the process in a suitable salt bath or the like.

Next, the mold shown in FIGS. 4 and 5 will be explained.
In the case shown in the figure, the undercoat material (2), the nickel-based self-melting alloy sprayed layer (3), and the chromium carbide layer (4) are coated on part of both sides of the mold body (1) or (up to the entire J). These surface coating layers are peeled off, especially those of the shape r#V as shown in the IAS diagram are sandwiched between a pair of opposing long sides and have a width i.
When used as an iJ variant short side mold, it is effective because the wear resistance on both sides is improved. In addition, the surface coating Ir40 history is used to prevent peeling and heat resistance on the upper and lower end surfaces.
Ili4: In order to improve wear and corrosion resistance, the coating layer may also be extended by wrapping it around the upper and lower end surfaces of the mold body.J)
Ru.

As described above, the mold according to the present invention has a mold body, an undercoat material, a sprayed layer, and a chromium carbide R4 of 411%.
The adhesion is strong because of the diffusion layer formed at each boundary W, and the adhesion is great. In particular, the chromium carbide that is the outermost layer is formed as a result of the carbonization reaction at that location41. Therefore, there is a chemical bond, and J) et al.
:The adhesion strength is significantly greater than that of chromium carbide bonded by thermal spraying or the like.

In addition, it has been remelted and sealed and is 1llii in itself.
The hardness of the abrasive thermal sprayed layer is more than I (v200 []), and its hardness does not decrease even in the high n1J range, and it has a high resistance to seizing with molten eggs and coagulated seals. Since it is coated with black and black carbide, it can be stably used for small fish that cause breakouts etc. during the period of <4?-.

Furthermore, the chromium carbide on the outermost surface of the present invention has the advantage that its corrosion resistance is low. There is an effect.

[Brief explanation of drawings]

Fig. 1 is a perspective 4 view of the mold of the present invention, Figs. 2 and 3 are side views of the same deformation, and Figs. 4 and 5 are perspective views of other deformations.゜In the figure, (1): tflf type body (2): Undercoat material (3): Nickel-based self-fusing alloy sprayed layer (4): Ri1
1 Mu Carbide In 1st E4 j'ri'+ 4 Ni"'1 2nd To 1 3rd r"i Procedural Amendment 31-124, 1982! lko f1・'l' l, '+'J-i", ``Kazuo Wakasugi Tono 1 small fi inner table Koaki+115711- Patent Application No. 165
No. 633: 2 Invention: 1. Mold for continuous casting and method of making the same lIζ; 3 Ministry 1ii1...I...
:, bar car ('1 and (]) relationship Patent Applicant 11 Specification 7, 1jli iE O) Part 1 (. Engraving of specification (no change in content) 227-

Claims (1)

[Claims] 1. An undercoat material made of nickel or a nickel alloy is applied on the inner surface of a mold body made of copper or copper alloy, and a nickel-based self-fusing alloy sprayed layer is applied on the undercoat material. , a continuous casting mold with a chromium carbide layer further applied on the same sprayed layer. 22. The mold for continuous fII production according to claim 1, characterized in that the sprayed layer of Kel-based self-fluxing alloy becomes a layer sequentially from the upper part of the mold to the lower part of the mold. A mold for continuous casting according to claim 1 or 2, characterized in that the layers gradually form toward the bottom of the mold. 4. Claim ff11 characterized in that the undercoat material, the nickel-based self-fusing alloy sprayed layer, and the chromium carbide layer are wrapped up to a part or all of the #-type main body near the inner surface of the image side. - The continuous casting mold according to any one of Item 3. 6. Internal installation of # type body made of copper or prepared alloy ii J:,
An undercoat material made of nickel or a nickel alloy is applied, a nickel-based self-fluxing alloy solvent layer is applied to the upper surface of the undercoat material, a chromium layer is further applied to the upper surface of the thermally sprayed layer, and then the thermally sprayed layer is remelted and the above-mentioned A method for producing a hook t (V) for continuous casting, characterized by heating and holding for 1 hour at a temperature necessary to react the entire chromium layer with the carbon contained in the sprayed layer to form a chromium carbide. 6. Nickel @fl characterized by C in which the base self-fusing alloy solvent layer has a layer thickness sequentially from the upper part of the mold to the lower part of the mold.
A method for manufacturing a continuous casting mold according to claim 5. 7. Feature r characterized in that the thickness of the chromium layer is increased sequentially from the upper part of the mold to the lower part +C of the mold [1!4! as set forth in claim 5 or 6! A method for manufacturing a mold for hard casting. 8. Undercoat layer 2. The Kel-base self-fusing alloy sprayed layer and the chromium layer are rolled up to part or all of the inner surface of both sides of the mold body. The method for manufacturing a continuous casting mold according to any one of items 5 to 7.