JP2014159356A - Molten glass gob molding die and production method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a molding die for molding a molten glass gob having a coating excellent in heat resistance, high-temperature wear resistance, lubricity, releasability or the like, which is formed in the coated state.SOLUTION: In a molten glass gob molding die 12, the inner surface of the die 12 having a contact with a molten glass gob is coated directly or via an undercoat with a metal boride cermet sprayed coating 14 comprising a metal boride and a heat-resistant metal-alloy, and the metal boride cermet sprayed coating 14 has a carbon particle filled-coated structure in which carbon particles are filled into an open pore part by impregnation, and the coating surface is also coated with the carbon particles. A production method thereof is also provided.

Description

  The present invention relates to a molten glass lump-molding mold and a method for producing the same, and in particular, is a new proposal characterized by a coating layer formed on the inner surface of a molding mold that comes into contact with the molten glass lump.

Generally, a glass bottle etc. are manufactured through the following processes. For example, a raw material composed of main raw materials such as soda ash, limestone, and glass scraps and auxiliary raw materials such as mirabilite (Na ₂ SO ₄ ), various colorants, and decolorizers is heated to a temperature of about 1500 to 1600 ° C. After melting and then removing bubbles, etc., the temperature is adjusted to about 1100 ° C. to 1200 ° C. according to the weight and shape of the bottle, and molten glass lump (high temperature lump glass in a softened state) through a feeder Finally, it is supplied to a bottle making machine, that is, a molding die.

  FIG. 1 shows an outline of a general glass bottle manufacturing process. Here, 1 shown in the figure is a molten glass, 2 is a glass melting furnace, 3 is a work chamber, 4 is a feeder, 5 is an orifice, and 7 is a molten glass lump. The molten glass 1 in the melting furnace 2 is processed in the working chamber 3 and the feeder 4, and then cut into a glass lump 7 having an appropriate size by a cutting machine 6. After that, it is fed into a bottle making mold (molten glass lump forming mold) 12 through a series of bowl-shaped conveying members called a funnel 8, a scoop 9, a trough 10, and a deflector 11, and the required glass. The bottle is molded.

By the way, the following properties are required for the surface of a cast iron substrate such as a molding die in contact with the molten glass lump.
(1) The coefficient of friction with molten glass is small and the slipperiness is good.
(2) It has excellent high temperature wear resistance and can maintain the initial performance for a long period.
(3) Dirt is difficult to adhere and does not contaminate the molten glass.
(4) Maintenance and inspection are easy and can be regenerated.
(5) Be economical

  In particular, for a mold for molding a molten glass lump, it is important that the frictional resistance is small, the glass lump can be smoothly inserted into the mold, and the moldability of the molded glass lump is excellent. .

  Conventionally, such a requirement has been dealt with by applying a lubricant composed of graphite powder (graphite powder) and resin or drying oil to the inner surface of the molding die in contact with the molten glass lump and the conveying member. Yes. While this conventional method has advantages such as easy operation, good sliding of the molten glass lump, and no adverse effect on the quality of the glass, the consumption rate of the graphite powder is large and it is frequently applied. There is also a drawback that it is necessary. Furthermore, the lubricant containing graphite powder has the property that the oil component is easily burned out and scattered in a short time, so that it not only deteriorates the working environment but also attaches to the worker and gives discomfort. There was also a drawback.

As countermeasures, proposals have been made to apply various surface treatment films to the surfaces of a molding die (member) in contact with a molten glass lump, a conveying member, a plunger, and the like. Certainly, these proposals are a significant improvement over untreated substrates. For example,
(1) In Patent Documents 1 to 5, a cermet sprayed coating using self-fluxing alloy, carbide (Cr ₃ C ₂ ) or oxide particles is coated on the surface of a molding plunger or the surface of a glass lump conveying member. Patent Documents 6 to 7 disclose a method of coating a nitride, carbide, oxide film, or the like on the surface of a molten glass lump supply jig.
(2) Patent Document 8 discloses a technique for coating a thin film such as TiN, TiCN, TiB ₂ , or SiC by a CVD method or a PVD method.
(3) Further, Patent Document 9 discloses a method of coating a sheet glass forming roll with a heat-resistant and corrosion-resistant alloy film.

  On the other hand, the inventors of the present application also proposed a film in which a metal having a low free energy of carbide generation such as Mo, Ta, W or the like is added as a metal component of carbide cermet on the surface of a bowl-shaped conveying member of a molten glass lump (Patent Document 10 Furthermore, a thermal spray coating member was proposed (Patent Document 11) using particles obtained by coating a thin film of Ni, W, Ti, Al or the like on the surface of graphite particles having excellent lubricity.

  There is also a proposal for coating various types of surface treatment film on the inner surface of a mold for molding a molten glass lump. For example, Patent Documents 12 and 13 disclose a metal film having Cu, Al, Cr as a main component and the balance of Fe coated on the inner surface of a mold, and Patent Documents 14 and 15 disclose a metal film. A technique is disclosed in which an aqueous solution in which BN and colloidal silica are dispersed is applied to the inner surface of the mold and then dried to form a film. In Patent Documents 16 to 18, a carbide or carbide cermet film is applied to the inner surface of the mold. Techniques for coating are disclosed.

  Subsequently, the inventors of the present application developed a cermet sprayed coating composed of a metal boride and a heat-resistant alloy as a sprayed coating excellent in releasability and durability for coating the inner surface of a mold for molding a molten glass lump. (Patent Documents 19 and 20).

JP 54-146818 A JP-A-2-111634 Japanese Patent Laid-Open No. 4-139032 JP-A-3-290326 JP-A-11-171562 Japanese Patent Laid-Open No. 2-102145 JP-A 63-297223 JP-A-1-239029 Japanese Patent Laid-Open No. 3-137032 JP 2002-20126 A JP 2002-20851 A JP-A-8-109460 JP-A-8-120435 Japanese Patent Laid-Open No. 2003-119049 Japanese Patent Laid-Open No. 2003-119047 JP-A-62-158122 JP-A-2-146133 JP 2002-178034 A JP 2012-136395 A JP 2012-136396 A

  Among the above-described conventional techniques, for example, in the case of a surface treatment film in which a lubricant containing graphite powder is applied to the inner surface of a mold, there are the following problems. It has the advantage that the mold surface coated with graphite powder has good lubricity and does not wrinkle even when it comes into contact with molten glass, but the lubricant tends to volatilize and pollute the work environment. There is also a drawback. In addition, since the determination of the application method and the application time all depend on the experience of skilled workers, there is a problem that it is difficult to unmanned operations such as automation and robotization.

In addition, conventional surface treatment techniques such as carbide cermet, oxide, nitride, heat-resistant alloy by thermal spraying method, CVD, PVD, etc. are insufficient, although some effects can be seen compared to the case of no treatment, There is a problem that it is often necessary to use in combination with a graphite powder coating technique.
By the way, conventionally, a member for transporting a molten glass lump and a “glass lump molding die” which is the subject of the present invention have different conditions and characteristics required for them, so that the surface originally corresponds to the required characteristics. Where processing is required, in practice, these have not been fully examined and remain unresolved.

  For example, for the conveying member, since the contact pressure between the hot molten glass lump and the surface treatment film formed on the surface thereof is small and the contact time is short, generally the lubrication performance of the film is an important management target. .

  On the other hand, in the case of a mold for molding, since the contact time with the molten glass block is long, heat resistance and high temperature wear resistance are required, and the surface treatment film surface has a minute roughness or slight traces. Since it is easily transferred to the glass surface, it is required to use a film or a material that can be easily processed such as grinding and polishing of the film surface. In addition, the entrance to the mold for forming the bottle is generally narrow, and the lubricity of the molten glass mass passing through it and the mold release of the molded product are also important characteristic factors. In fact, surface treatment coatings with characteristics, particularly thermal spray coatings, have not yet been developed.

In recent years, since safety awareness of the work environment and glass molded products has been improved, measures and examinations regarding the generation of harmful substances are also necessary. In this regard, conventional thermal spray coatings are often made of Cr-containing compounds such as chromium carbide (Cr ₃ C ₂ ), Ni—Cr alloys, self-fluxing alloys, and Cr-containing alloys. Although there is a possibility that a hexavalent chromium compound that is oxidized in the environment and partially harmful is produced, these problems remain unsolved.

  The purpose of the present invention is to improve the properties of the boride cermet sprayed coating, that is, excellent heat resistance, high temperature wear resistance or releasability from the molten glass lump, as well as improving the quality of glass products and the safety of bottle making operations. The object is to propose a mold for forming a molten glass lump and a method for producing the same, which is highly environmentally friendly.

  The object of the present invention is as follows. First, a metal boride cermet sprayed coating composed of a metal boride and a refractory metal / alloy is coated directly or through an undercoat on the inner surface of the mold contacting the molten glass block. The metal boride cermet sprayed coating is filled with carbon particles in the open pores by impregnation treatment, and the coating surface is coated with carbon particles. This can be realized by adopting a mold for forming a molten glass block characterized by having a structure.

  Secondly, the object of the present invention is to provide a metal boride cermet sprayed material comprising a metal boride and a refractory metal / alloy directly or through an undercoat on the inner surface of the molding die that contacts the molten glass lump. A metal boride cermet sprayed coating with a thickness of 50 to 1000 μm is formed by spraying by any one of the air plasma spraying method, the low pressure plasma spraying method, the high-speed flame spraying method, and the explosion spraying method. After that, carbon particles are impregnated and filled from the open pores on the surface of the sprayed coating, and at the same time the surface is coated, and then fired to form a metal boride cermet sprayed coating having a carbon particle filling-coating structure. It can be realized by adopting a manufacturing method of a mold for forming a molten glass lump.

In the present invention, in addition to the basic configuration described above,
(1) The metal boride cermet spraying _{material, TiB 2, ZrB 2,,} HfB 2, VB, TaB, NbB, W 2 B 5, CrB 2, NiB and any one or more metal boride selected from MoB 20 to 90 mass%, and the balance is made of Ni-Cr alloy containing Ni or Cr content of less than 50 mass%,
(2) In the metal boride cermet sprayed coating containing a Ni—Cr alloy as a heat-resistant alloy, at least a part of Cr is changed to a chromium carbide compound,
(3) The Ni-Cr heat-resistant alloy in the metal boride cermet has a Cr content of 50 mass% or less.
(4) The particle diameter of the carbon particles filled by impregnation into the open pores of the metal boride cermet sprayed coating is 1 nm to 10 μm,
(5) The undercoat is made of Ni-Al, Ni-Cr, Ni-Cr-Al, self-fluxing alloy, MCrAlX alloy (where M is Co and / or Ni, and X is any one selected from rare earth elements) A thermal spray coating of the above alloy) having a thickness of 50 to 150 μm,
(6) The metal boride cermet sprayed coating has a smooth surface with a surface roughness Ra of 5 μm or less and Rz of 15 μm or less.
(7) The metal boride cermet sprayed coating having a carbon particle filling-coating structure is selected from water, an organic solvent, oil, viscous oils and fluids, or a high molecular compound with respect to the surface of the sprayed coating. The slurry obtained by mixing carbon particles having a particle size of 1 nm to 10 μm is sprayed on the above medium, immersed or coated, and the carbon particles are first impregnated in the open pores of the film, and then 100% in an electric furnace. By applying a heat treatment at 550 ° C. to 550 ° C. for 1 to 5 hours to fill only the carbonaceous matter inside the pores of the thermal spray coating, and at the same time, leave it on the surface of the coating to coat,
(8) In the metal boride cermet sprayed coating containing a Ni—Cr alloy as a heat-resistant alloy, at least a part of Cr is changed to a chromium carbide compound,
(9) The surface of the metal boride cermet sprayed coating with the carbon particle filling-coating structure is machined to finish to a smooth surface with Ra: 5 μm or less, Rz: 15 μm or less,
It is considered that a more preferable embodiment is configured as described above.

  According to the production of the glass lump molding die according to the present invention configured as described above, in addition to excellent heat resistance, high-temperature friction resistance, releasability from the molten glass lump, initial mold dimensional accuracy, etc. In addition to maintaining the mold characteristics for a long time, it can greatly contribute to the production of high-quality glass molded products.

  Moreover, according to the method for producing a glass lump molding mold according to the present invention, there is no generation of harmful hexavalent chromium compounds from the spray coating component, and a safe and hygienic working environment can be provided. Glass products can be manufactured safely. In particular, by impregnating and filling the open pores of the thermal spray coating with carbon particles, it is possible to omit or regularly reduce the application frequency of the graphite powder on the mold member surface that has been conventionally employed. In addition to preventing the generation of the hexavalent chromium compound, it greatly contributes to the improvement of the working environment.

It is a basic diagram of the glass bottle manufacturing process which shows the outline of the conveyance process of a molten glass lump, and the supply process to the metal mold | die for shaping | molding. It is the figure which showed the manufacturing process of the metal mold | die which coat | covered the metal boride cermet sprayed coating of the filling-coating structure of a carbon particle. It is a cross-sectional schematic diagram of each metal boride cermet sprayed coating before and after impregnating carbon particles in the open pores. (A) before impregnation treatment, (b) after impregnation treatment

  As a result of intensive studies to solve the above-mentioned problems of the prior art, the inventors have arrived at the solution means described below, and the details of the configuration will be described. FIG. 2 shows a manufacturing process for impregnating and filling carbon particles into the open pores of a metal boride cermet sprayed coating on the inner surface of a mold for molding a molten glass lump. Is. In the following, details of the configuration of the present invention will be described in the order of the steps.

(1) Base material In the present invention, the base material of the ingot mold for forming the metal boride cermet sprayed coating is made of steel such as cast iron, cast steel, carbon steel, tool steel, and low alloy steel. Is preferred. In addition, non-ferrous metals such as Al and alloys thereof, Ti and alloys thereof, and Mg alloys, ceramic sintered bodies, sintered carbon, powder sintered materials, and the like can also be used.

(2) Pretreatment The substrate for forming the cermet sprayed coating is subjected to cleaning treatment by degreasing and descaling in accordance with the ceramic sprayed coating work standard preliminarily defined in JIS H9302. Thereafter, it is preferable to perform blast roughening treatment by spraying abrasive particles such as A1 ₂ O ₃ or SiC. The surface roughness after the blast treatment is preferably about Ra: 1 to 10 μm and Rz: about 5 to 40 μm.

(3) Undercoat In the present invention, an undercoat is formed on the surface of the mold base as necessary. As the material for forming the undercoat, Ni-Al, Ni-Cr, Ni-Cr-Al, self-fluxing alloy (JISH8303), M ( Ni or Co) -Cr-Al-X alloy (where X is a rare earth element such as Y, Ce, La) is preferable. The thickness of the undercoat layer is preferably about 50 to 150 μm, and particularly preferably about 50 to 100 μm. The reason is that if the film thickness is less than 50 μm, the function of the undercoat is not sufficient, and even if a film thickness of 150 μm or more is formed, the effect of the undercoat is saturated, leading to an increase in production cost. Because.

(4) Topcoat A metal boride cermet sprayed coating is formed as a topcoat directly or via the undercoat on the surface of the mold base. The metal boride cermet sprayed coating and the metal boride cermet sprayed powder material will be described below.
The metal boride cermet sprayed powder material used in the present invention is composed of the following metal boride and a refractory metal / alloy.
(A) Boride: TiB ₂ , ZrB _2, HfB ₂ , VB, TaB, NbB, W ₂ B ₅ , CrB ₂ , NiB, MoB (Note that the molecular formula of boride varies depending on the manufacturing conditions, so it is absolute (This is based on the indication of commercial products.)
(B) Heat-resistant metal / heat-resistant alloy;
a. Refractory metal: Metal Ni (single or mixed with Ni-Cr alloy)
b. Heat-resistant alloy: Ni-Cr alloy containing less than 50 mass% of Cr

  The metal boride cermet sprayed powder material is a mixture of a metal boride and a refractory metal / alloy, and the mixing ratio of the metal boride is 20 to 90 mass%, and the refractory metal / alloy is 80 to 10 mass%. To do. The more preferable mixing ratio of these is metal boride: 40 to 60 mass%, and the balance is a refractory metal / alloy. In the present invention, focusing on the metal boride, the reason for limiting the composition of the metal boride to the above range is that the metal boride having the composition in this range is hard and excellent in high temperature wear resistance, This is because the reactivity with the glass lump in the state is small, so that there is little possibility of inducing a fusing phenomenon, and furthermore, it is excellent in releasability (releasability) from the molded glass product. On the other hand, the component of the refractory metal / alloy is mixed with metal boride particles so as to improve the mutual bonding force between the particles at the time of thermal spray coating formation, and the laminated structure of only metal boride particles. In this case, the formation of a large gap seen at the time is prevented, and it is easy to control within a range effective for forming a sprayed coating having a pore diameter and a pore distribution suitable for a carbon particle impregnation process in the next step.

  That is, if the content of the refractory metal / alloy is less than 10 mass%, the effect of adding the refractory metal / alloy is not sufficient, and if the content of the metal boride is less than 20 mass%, the excellent heat resistance of the metal scrap boride Characteristics such as heat resistance, high temperature stability, and high temperature wear resistance cannot be obtained sufficiently. The thermal spray coating is cermetized to improve the adhesion between the substrate and the coating.

(5) Formation method of metal boride cermet sprayed coating As a method of forming a sprayed coating by spraying metal boride cermet sprayed powder material on the surface of the mold base, atmospheric plasma spraying, low pressure plasma spraying, high speed Flame spraying method, explosion spraying method, etc. can be applied. In addition, film formation is possible by worm spray and cold spray in which the temperature of the spraying atmosphere gas is kept low. The metal shelf cermet sprayed coating by these methods may be directly formed on the inner surface of the mold (base material). First, after applying an undercoat on the surface of the base material, the metal boride cermet is used as a top coat. The thermal spray coating may be coated and laminated.

  The thickness of the metal boride cermet sprayed coating is preferably in the range of 50 to 1000 μm, particularly preferably 100 to 300 μm. The reason is that when the thickness is less than 50 μm, it is impossible to form a film with a uniform thickness on the surface of the substrate. On the other hand, in the case of a sprayed coating having a thickness of more than 1000 μm, the spraying time becomes longer and the sprayed material This is because, in addition to an increase in the amount used, impregnation treatment with carbon particles takes a long time, leading to an increase in production cost.

  In addition, since the metal boride cermet sprayed coating of the present invention contains a metal / alloy component at a ratio of 10 to 80 mass%, the undercoat is not an essential condition, but a thick film, for example, 300 μm or more is used. In the case of forming a film, it is desired to improve the adhesion with the top coat. Therefore, it is desirable to apply an undercoat if possible.

(6) Impregnation-filling and coating of carbon particles in metal boride cermet sprayed coating In the metal boride cermet sprayed coating formed by the spraying method, there are usually pores peculiar to the sprayed coating. The porosity of this sprayed coating varies depending on the spraying method and spraying conditions, but according to the knowledge of the inventors, the atmospheric plasma spraying method is 5 to 16%, the low pressure plasma spraying method is 0.8 to 4%, and the high-speed flame spraying method. It is about 5 to 15% (area ratio obtained by measuring the cross section of each film with an image analysis device), and these pores are classified as follows according to the existence form.
(i) Sealed pores: pores closed inside the film (also called closed pores)
(ii) Open pores: pores leading to the outside of the coating (also called open pores)
(iii) Through pores: pores that connect from the surface of the coating to the substrate
(iv) Continuous vent: A pore in which a plurality of pores are connected to each other inside the membrane with pores leading to the outside of the membrane

  Although the presence of the pores contributes to a decrease in the thermal conductivity of the thermal spray coating, it becomes a penetration path for gaseous and liquid corrosive components and causes a decrease in the corrosion resistance of the thermal spray coating product. However, it is often treated as a fault. Furthermore, the presence of these pores may hinder the improvement of accuracy during the surface processing (polishing) of the film, and it may cause the quality of the glass product after molding (lack of smoothness, transcription of surface disease, etc.) to deteriorate. It is also a major technical issue.

  In the present invention, the smoothness of the surface of the sprayed coating is improved by impregnating and filling the fine pores of carbon inside the open pores of the metal boride cermet sprayed coating, and the sprayed coating is lubricated with a molten glass lump. It is characterized by imparting properties excellent in properties and releasability. As a result, in the case of the present invention, it is not necessary to apply and supply carbon during the molding operation, and the quality of the molded glass product is improved.

First, a method for impregnating carbon particles into the open pores of the thermal spray coating will be described. The following properties are recommended as carbon particles to be injected into the open pores of the metal boride cermet sprayed coating.
(I) As the carbon, natural graphite, carbon obtained from fossil fuels such as petroleum and coal, soot obtained by burning and carbonizing vegetable oil, carbon obtained by firing a polymer material, and the like are suitable.
(ii) The carbon particles have a particle size of 1 nm to 10 μm and are sprayed on the thermal spray coating in the form of a water slurry or oil slurry, or the thermal spray coating is immersed in the carbon particles into the open pores. Particles are fed and impregnated.
(iii) As another supply method, carbon particles can be mixed in viscous oils such as grease and petrolatum and impregnated by applying them to the surface of the sprayed coating. Grease and petrolatum have the advantage of improving the carbon particle impregnation effect in the heating step after the impregnation, by themselves being thermally decomposed to become a carbon source.

  When impregnating the carbon particles into the sprayed coating, it is convenient to reduce the environment to atmospheric pressure or lower or to heat the sprayed coating to about 50 to 150 ° C. in advance because grease and petrolatum can easily enter inside. is there.

  The thermal spray coating impregnated with carbon particles is heated at 100 ° C. to 550 ° C. for about 1 to 5 hours in an electric furnace to evaporate and volatilize water, oil, and organic solvents in the slurry, For petrolatum, only the carbon component produced by the pyrolysis reaction remains together with the carbon particles in the pores of the coating. In addition, since the impregnation (heating) treatment of one time may not sufficiently fill the pores of the sprayed coating with carbon particles, in such a case, by repeatedly performing the impregnation and heating operation of the carbon particles, The filling rate of carbon particles can be increased. By such an operation, the carbon particles adhere and remain on the surface of the cermet sprayed coating, but these carbon particles also play an important role. The sprayed coating after such a treatment is hereinafter referred to as a sprayed coating having a carbon particle filling-coating structure.

FIG. 3 is a schematic cross-sectional view of the sprayed coating before and after impregnating and filling the open pores with carbon particles, and heating and sintering. FIG. 3 (a) shows a cross section of a metal boride cermet sprayed coating immediately after spraying, in which a metallic undercoat 32 is applied to the surface of the substrate, and a metal boride and a heat resistant alloy are used as a top coat on the surface. An example is shown in which a deposited layer 33 of metal boride cermet particles comprising: In general, many metal borides have a high melting point (for example, ZrB ₂ : 3250 ° C., CrB ₂ : 2200 ° C.), and even when exposed to a high temperature environment, they soften or exhibit flow phenomena like metals. Therefore, even when sprayed with a plasma heat source, the boride particles can be sprayed onto the undercoat surface or the substrate surface in an incompletely melted state. Therefore, in this case, since the fusion of the laminated particles becomes insufficient, gaps of various sizes are inevitably generated, and this is the pore source of the sprayed coating. That is, in combination with the structure of the thermal spray coating, the use of a metal boride forms a thermal spray coating having open pores suitable for the present invention. 34 schematically shows closed pores and 35 shows open pores.

  On the other hand, FIG.3 (b) shows the cross-sectional schematic diagram of the sprayed coating after impregnating a carbon particle. The sprayed coating has a portion 36 (black portion) in which carbon particles are impregnated and filled in the open pores 35 where the portions where the metal boride cermet particles 33 are not sufficiently fused with each other exist as voids. The front end of the filling portion is in the state of a carbon particle layer 37 that is exposed and covered to the surface of the thermal spray coating. In addition, the exposed portions 37 of the carbon particles are distributed in the form of spots over the entire surface of the sprayed coating.

  Therefore, when the molten glass comes into contact with the surface of the boride cermet sprayed coating having a portion where the carbon particles are exposed at the time of forming the molten glass lump, the molten glass exists in the form of spots in addition to the metal boride-heat resistant alloy. The carbon particle exposed portion is also brought into contact at the same time, improving the fluidity of the molten glass and demonstrating the action of promoting the release of the glass product after molding. During the impregnation treatment of the carbon particles, the carbon particles are formed (coated) on the surface of the sprayed coating, so that the film-like carbon particles are also useful for forming a molten glass lump. I do.

(6) Grinding / polishing of film surface The metal boride cermet sprayed coating having a carbon particle filling-coating structure is preferably subjected to grinding / polishing by machining. The surface of the thermal spray coating impregnated with carbon particles is very rough with Ra: about 5 to 10 μm and Rz: about 15 to 25 μm. Become. Therefore, in the present invention, it is preferable to finish the smooth surface with Ra: less than about 5 μm and Rz: less than about 15 μm. In addition, when the surface of the thermal spray coating is ground and polished, there is a case where a pore portion that has existed as closed pores during the impregnation treatment with the carbon particles is changed to open pores. For this reason, it is recommended to repeat the impregnation and filling process of the carbon particles for the sprayed coating after polishing again.

  The reason why the surface roughness of the metal boride cermet sprayed coating is Ra ≦ 5 μm is to reduce the contact resistance with the molten glass lump and ensure a smooth glass molding surface, while Rz <15 μm. The reason for this is that the roughness of the sprayed coating is transferred to the glass molding surface, which may cause defective products.

(7) Features of a metal boride cermet sprayed coating having a carbon particle filling-coating structure The coating surface of the metal boride cermet spraying coating having a carbon particle filling-coating structure obtained by impregnating carbon particles into a spraying coating. Since at least a part of the carbon exists in an exposed state, it comes into direct contact with the molten glass for molding, and this exhibits excellent lubricity and releasability. In addition, the surface of the thermal spray coating is coated, and the heat-resistant alloy particles (Cr) of the coating components that come into contact with the carbon particles filled in the open pores react with each other, so that the same lubricity and mold release as carbon There is also an effect of generating chromium carbide having the properties on the surface of the alloy particles.

Further, the carbon particles in the open pores of the coating are added as carbon particles and a cermet component in the thermal spray coating when heated and fired for impregnation and when in contact with the hot molten glass lump. The Cr components of the particles react with each other to produce chromium carbide (Cr ₂ C ₃ , Cr ₂₃ C ₆ ), thereby completely covering the surface of the alloy particles. Therefore, the action of the metal Cr component having a strong bonding force with the molten glass suppresses the passage of glass lumps at the entrance of the molding die having a narrow shape that frequently occurs, and on the surface of the sprayed coating in contact with the glass The film is made only of metal boride, chromium carbide, and carbon particles having excellent lubricity and releasability. In addition, a more characteristic feature is that when the metal boride cermet sprayed coating having a carbon particle filling-coating structure according to the present invention is used, it is effective in preventing the generation of hexavalent chromium as a work environment pollutant. In-mold surface treatment can be performed.

Example 1
In this example, the adhesion of a cermet sprayed coating composed of a metal boride and a heat-resistant alloy was investigated by a thermal shock test method.

(1) Test base material: As the test base material, SUS410 steel (dimensions: width 50 mm × length 50 mm × thickness 3.9 mm) was used.
(2) Film forming material: CrB ₂ , MoB, ZrB ₂ , W ₂ B ₅ are used as metal borides, and Ni or (Ni-20 mass% Cr) Ni—Cr alloy is used for each metal boride particle. A cermet sprayed powder containing 50 mass% was prepared. Then, a film having a thickness of 150 μm was formed on one side of the substrate by the atmospheric plasma spraying method using this cermet sprayed powder. As a comparative example, a film having a thickness of 150 μm was formed from the boride particles alone and the Ni—Cr alloy film by atmospheric plasma spraying.
(3) Carbon particle impregnation: All test coatings were impregnated with oil slurry-like carbon particles according to the present invention, and the thermal shock resistance was compared with the test coating without impregnation treatment.
(4) Test method: After the above-mentioned sprayed coating-coated test piece is heated in an electric furnace at 650 ° C. for 15 minutes, this is taken out of the furnace and cooled to a temperature of 80 ° C. or less while flowing air from the blower. The test was repeated for a total of 10 cycles. In each cycle test, the surface of the sprayed coating was observed with a magnifying glass (× 8) to check for “cracking” and local peeling.
(5) Test results: Table 1 shows the test results. As is clear from this result, the thermal spray coating (Nos. 9 to 16) of only the boride of the comparative example generated cracks and local peeling portions on the surface of the coating by repeating the thermal shock cycle 5 to 7 times. . On the other hand, the metal boride cermet sprayed coating (Nos. 1 to 8) conforming to the present invention was not cracked or peeled off even by a 10-cycle thermal shock test, and only the Ni—Cr alloy of the comparative example was sprayed. It was confirmed that the adhesiveness equivalent to the films (Nos. 1 and 18) was exhibited. Further, according to the present invention, in the case of a sprayed coating in which carbon particles are impregnated and filled in the open pores of the coating, excellent adhesion was exhibited without affecting the thermal shock resistance (No. 1, 3, 5, 7, 9).

(Example 2)
In this embodiment, a metal boride cermet spray powder obtained by spraying a metal boride cermet spray powder obtained by changing the Cr content in the Ni—Cr alloy added to the metal boride is sprayed on the base material. The presence or absence of a hexavalent chromium compound produced when the film was heated in air and the adhesion between the molten glass were examined.

(1) Test base material: The same base material as in Example 1 was used.
(2) Film forming material: A cermet sprayed powder material is prepared using an alloy in which MoB is used as a boride and the Cr content in the Ni-Cr alloy added thereto is changed within a range of 5 to 55 mass%. A metal boride cermet sprayed film having a thickness of 150 μm was formed by an atmospheric plasma spraying method. The ratio of the metal boride to the refractory metal / alloy was 50:50. As a comparative example, a sprayed coating of Cr: 100 mass% was also prepared.
(3) Production test of hexavalent chromium: In this test, the test film was heated in an electric furnace at 980 ° C. for 100 hours, and then the metal oxide formed on the film surface was collected and subjected to chemical analysis. The presence or absence of a hexavalent chromium compound contained in the oxide was qualitatively examined.
(4) Adhesion test method with molten glass: After a molten glass lump of 1200 ° C. is pressure-bonded to the surface of the test film, it is allowed to cool to room temperature, and the glass lump fixed to the film surface is knocked down with a wooden hammer. Thus, the adhesion of the glass lump was qualitatively examined.
(5) Test results: The test results are shown in Table 2. As is clear from this result, it has been found that as the Cr content in the Ni—Cr alloy increases, the tendency to produce a hexavalent chromium compound increases. However, in the cermet sprayed coating impregnated with carbon particles, the formation of hexavalent chromium compounds was not observed even in Ni—Cr alloys (No. 7, 9, 11, 13) containing Cr content of 28 mass% or more. It turns out that it does not cause contamination. This is because the surface of Ni—Cr alloy particles in the thermal spray coating impregnated with carbon particles reacts with the carbon particles to produce chromium carbide compounds (Cr ₃ C ₂ , Cr ₂₃ C ₆ ), and Ni—Cr It is presumed that the contact between the alloy and air (oxygen gas) is prevented, and the formation of hexavalent chromium oxide is suppressed by giving priority to the carbonization reaction over the oxidation reaction. Furthermore, since the chromium carbide compound formed in the form of a film on the surface of the Ni—Cr alloy particles is excellent in high temperature environment resistance, once formed on the surface of the alloy, it exhibits high temperature oxidation resistance over a long period of time and exhibits hexavalent chromium. It is considered that the formation of a compound (for example, CrO ₃ ) was prevented. From these results, the impregnation treatment with carbon particles not only suppresses the generation of hexavalent chromium compounds as a cause of environmental pollution, but also contributes to the expansion of the selection range of the heat-resistant alloy composition necessary for forming a cermet sprayed coating. I can see.

  Further, the adhesion of the molten glass lump to the test film tends to become stronger as the Cr content in the Ni-Cr alloy increases, and in particular, in the case of only a Cr cermet film (No. 4), peeling of the pressed glass lump is performed. It was so strong that it was difficult. On the other hand, all the test films impregnated with carbon particles showed good peelability regardless of the amount of Cr in the Ni—Cr alloy and were effective in suppressing the formation of hexavalent chromium compounds. That is, it was confirmed that the chromium carbide film has a great effect on both the releasability of the glass lump and the suppression of hexavalent chromium compound molding.

(Example 3)
In this example, the impregnation effect of carbon particles on the adhesion of the cermet sprayed coating obtained by changing the ratio of the refractory metal / alloy component added to the metal boride and the peelability from the molten glass lump was investigated.

(1) Test base material: SUS410 steel as a test base material (dimensions: width 50 mm × length 70 mm × thickness 3.2 mm)
Was used as a test piece.
(2) Test film: MoB was used as a metal boride, and a cermet sprayed coating in which Ni-50 mass% Cr alloy particles were changed at a rate of 10 to 90% by weight was applied to the substrate by an atmospheric plasma spraying method. It was formed to a thickness of 150 μm on one side. Moreover, as a film of the comparative example, a film of 100% each of MoB film and Ni—Cr alloy was formed to a film thickness of 150 μm by the atmospheric plasma spraying method.
(3) Carbon particle impregnation: A cermet sprayed coating impregnated with oil slurry-like carbon particles (an impregnation / firing cycle was repeated three times) was investigated as an invention example.
(4) Test method: The film adhesion was carried out by the thermal shock test method disclosed in Example 1, and the peelability from the molten glass lump was carried out by the test method employed in Example 2.
(5) Test results: The test results are shown in Table 3. As is apparent from the results shown in this table, the adhesion of the film is better as the content of the heat-resistant alloy particles is larger, and in the film containing only MoB (No. 1 and 2), the presence or absence of the carbon particle impregnation treatment is determined. Regardless, cracks occurred in the film in 6 cycles, and a peeling phenomenon was observed in a part of the film. The cermet sprayed coating (Nos. 3 to 14) containing 10 mass% or more of heat-resistant alloy particles maintains a good state without any abnormality even after the thermal shock test of 10 cycles. It was confirmed that the adhesion of the film was not affected.
On the other hand, in the pressure-bonding test with the molten glass lump, the peelability of the glass lump is slightly deteriorated with a coating (No. 4) having an addition amount of heat-resistant alloy particles of 10 mass% or more, and a cermet sprayed coating (No. 6, 8, 10, 12, 14) and the coating of only a heat-resistant alloy (No. 16), it was confirmed that the bondability was so strong that it was difficult to peel off the glass lump.
On the other hand, in the sprayed coating impregnated with carbon particles, the direct bonding between the molten glass lump and the Ni—Cr alloy particles is hindered by the presence of the carbon particles and the chromium carbide compound formed on the surface of the Ni—Cr alloy. The peelability between the test film and the glass lump was extremely good (No. 3, 5, 7, 9, 11, 13, 15).

Example 4
In this example, the actual working conditions of various sprayed coatings and prior art graphite coatings, etc., including the boride cermet sprayed coating conforming to the present invention impregnated with carbon particles on the surface of the bottle mold The bottle workability below was investigated.

(1) Test mold: The following sprayed coating was formed on the surface of a cast iron mold.
As a thermal spray coating suitable for the present invention, a metal boride cermet thermal spray coating in which 50 mass% of Ni-40 mass% Cr alloy is mixed with MoB and W ₂ B ₅ to a thickness of 250 to 300 μm is formed by an atmospheric plasma spraying method. did. Thereafter, this sprayed coating was filled with carbon particles in the open pores with an oil slurry containing carbon powder. Further, a metal oxide cermet sprayed coating obtained by mixing 50 mass% of Ni-20 mass% Cr alloy with an oxide such as A1 ₂ O ₃ , ZrO ₂ .8Y ₂ O ₃ as a thermal spray coating of a comparative example is performed by an atmospheric plasma spraying method. A method of directly applying graphite powder to the surface of a metal having a thickness of 250 to 300 μm was tested. Furthermore, the surface of these test films was finished to a roughness of Ra: 5 μm or less and Rz: 15 μm or less by machining.
(2) Test: The test items of the test film in the bottle manufacturing plant during actual work are observation of the state of insertion of the molten glass lump into the mold and observation of the test surface (crack, local peeling, etc.) .
(3) Test results: The test results are shown in Table 4. As is clear from the results shown in this table, the A1 ₂ O ₃ cermet film of the comparative example (No. 3) has a large insertion resistance into the mold of the molten glass lump, and it is often necessary to apply graphite powder. It was. Further, it was confirmed that cracks occurred in the coating after completion of the test and the thermal shock resistance was poor. In addition, the ZrO ₂ · 8Y ₂ O ₃ cermet sprayed coating exhibited strong resistance to thermal shock, and no large cracks were observed on the surface of the coating, but the insertion resistance of the molten glass lump into the metal Was found to be large and lack practical utility.
In contrast, the coating (No. 1, 2) in which the metal boride cermet sprayed coating is impregnated with carbon particles can smoothly perform the connecting operation for 150 hours or more, and the molded glass bottle has a quality problem. No good product was obtained. In addition, the graphite coating treatment for the mold of the comparative example has many problems such as the need for skilled workers in addition to the environmental pollution by graphite.

(Example 5)
In this example, the heat-resistant alloy (Ni—Cr) was kept constant, and the effect of the carbon particle impregnation treatment on the cermet sprayed coating when mixed with various metal borides was determined by an adhesion test with a molten glass lump.

(1) Test substrate: A test piece having the same steel type and dimensions as in Example 2 was used.
(2) Film forming material: CrB ₂ , ZrB ₂ , MoB, TaB, W ₂ B ₅ were used as metal borides, and 50% by mass of Ni-50 mass% Cr alloy was added to each metal boride. The sprayed coating was formed to a thickness of 200 μm by the atmospheric plasma spraying method. As a comparative example, a graphite coating and a Ni-based self-fluxing alloy (SFNi type 4 specified in JISH 8303) were sprayed.
(3) Impregnation of carbon particles: The same method as in Example 3 was used.
(4) Test method: The peelability from the molten glass lump was investigated by the method described in Example 2.
(5) Test results: Table 5 shows the test results. As is clear from the results shown in this table, the conventional general-purpose graphite coating treatment (No. ll) showed extremely good peelability of the molten glass lump, while the environment was significantly contaminated by graphite powder. It was also confirmed that In addition, it was found that the self-fluxing alloy film (No. 12) was not practical because of poor peelability from the molten glass lump. In contrast, various metal boride cermet sprayed coatings are not sufficiently peelable from the molten glass lump when used in the coating state (No. 2, 4, 6, 8, 10,), but impregnated with carbon particles. Showed good peelability. From these results, in the cermet sprayed coating using the Ni—Cr alloy having a high Cr content in the heat-resistant alloy even when the metal boride is applied, a trivalent chromium compound (Cr ₂ ) formed on the surface of the Ni—Cr alloy particles. It was found that the presence of O ₃ ) generates a bonding force with the molten glass lump and hinders peelability.

  The technology of the present invention includes the above-mentioned mold for molding a molten glass lump, as well as a member for conveying a molten glass lump in a glass filling manufacturing process, a large glass molded article, a glass plate material, and a wind glass molded article for an automobile. It is also useful as a surface treatment technique for rolls and other high-temperature transport rolls.

DESCRIPTION OF SYMBOLS 1 Molten glass 2 Glass melting furnace 3 Work room 4 Feeder 5 Orifice 6 Glass cutting machine 7 Crow lump 8 Funnel 9 Scoop 10 Trough 11 Deflector 12 Mold for bottle making 13 Molded bottle 14 Sprayed coating 31 Base material 32 Undercoat 33 Deposited layer of metal boride cermet spray particles (spray coating)
34 Closed pores 35 Open pores 36 Carbon particles filled in the open pores 37 Carbon particles covering the surface of the thermal spray coating

Claims (13)

  A metal boride cermet sprayed coating made of a metal boride and a refractory metal / alloy is coated directly or via an undercoat on the inner surface of the mold that comes into contact with the molten glass lump, and the metal boride cermet The thermal spray coating has a carbon particle filling-coating structure in which carbon particles are filled into the open pores by impregnation, and the coating surface is coated with carbon particles. . The metal boride cermet sprayed material may be any one or more metal borides selected from TiB ₂ , ZrB _2, HfB ₂ , VB, TaB, NbB, W ₂ B ₅ , CrB ₂ , NiB and MoB. The molten glass lump molding die according to claim 1, comprising 90 mass%, the balance comprising Ni-Cr alloy having Ni or Cr content of less than 50 mass%.   3. The molten glass ingot molding according to claim 1, wherein in the metal boride cermet sprayed coating containing a Ni—Cr alloy as a heat-resistant alloy, at least a part of Cr is changed to a chromium carbide compound. 4. Mold.   The molten glass lump molding die according to any one of claims 1 to 3, wherein the Ni-Cr heat-resistant alloy in the metal boride cermet has a Cr content of 50 mass% or less.   The molten glass according to any one of claims 1 to 4, wherein the particle diameter of the carbon particles filled by impregnation into the open pores of the metal boride cermet sprayed coating is 1 nm to 10 µm. Mold for lump molding.   The undercoat is Ni-Al, Ni-Cr, Ni-Cr-Al, self-fluxing alloy, MCrAlX alloy (where M is Co and / or Ni, and X is one or more alloys selected from rare earth elements) The molten glass lump molding die according to any one of claims 1 to 5, characterized in that the film thickness is 50 to 150 µm.   The molten metal block molding gold according to any one of claims 1 to 6, wherein the metal boride cermet sprayed coating has a smooth surface with a surface roughness Ra of 5 µm or less and an Rz of 15 µm or less. Type.   Metal boride cermet sprayed material consisting of metal boride and refractory metal / alloy directly or through an undercoat on the inner surface of the mold that comes into contact with the molten glass lump, atmospheric plasma spraying, reduced pressure plasma spraying, high speed A metal boride cermet sprayed coating having a film thickness of 50 to 1000 μm is formed by spraying by a flame spraying method selected from a flame spraying method and an explosion spraying method, and then an open pore portion on the surface of the sprayed coating A metal borate cermet sprayed coating having a carbon particle filling-coating structure is obtained by impregnating and filling carbon particles from the surface, followed by firing, followed by firing. Method.   The metal boride cermet sprayed coating having a carbon particle filling-coating structure is one or more media selected from water, organic solvents, oil, viscous oils and fats, and polymer compounds having fluidity on the surface of the sprayed coating. A slurry obtained by mixing carbon particles having a particle diameter of 1 nm to 10 μm is sprayed, dipped or coated, and the carbon particles are first impregnated into the open pores of the film, and then heated at 100 ° C. to 550 in an electric furnace. The melt according to claim 8, wherein only the carbonaceous material is filled in the sprayed coating and is left on the surface of the coating at the same time by performing a heat treatment at 1 ° C for 1 to 5 hours. A method for producing a glass lump-molding mold. The metal boride cermet sprayed material is one or more selected from TiB ₂ , ZrB ₂ , HfB ₂ , VB, TaB, NbB, W ₂ B ₅ , CrB ₂ , NiB and MoB as the metal boride. 10. The molten glass ingot mold according to claim 8 or 9, wherein the metal boride is 20 to 90 mass%, and the balance is Ni-Cr alloy with Ni or Cr content of less than 50 mass%. Production method.   The molten metal according to any one of claims 8 to 10, wherein in the metal boride cermet sprayed coating containing a Ni-Cr alloy as a heat-resistant alloy, at least a part of Cr is changed to a chromium carbide compound. Mold for glass lump molding.   The undercoat is Ni-Al, Ni-Cr, Ni-Cr-Al, self-fluxing alloy, MCrAlX alloy (where M is Co and / or Ni, and X is one or more alloys selected from rare earth elements) The method for producing a molten glass gob molding mold according to any one of claims 8 to 11, wherein the thermal spray coating is a film thickness of 50 to 150 µm.   The surface of the metal boride cermet sprayed coating having a carbon particle filling-coating structure is mechanically processed to have a smooth surface with Ra: 5 μm or less and Rz: 15 μm or less. The manufacturing method of the metal mold | die for molten-glass lump shaping | molding of any one.

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