KR20080051833A - Manufacturing method of the oxide dispersed platinum material using a thermal spray process - Google Patents

Abstract

A preparation method of an oxide dispersion strengthened platinum material using a thermal spray coating process is provided to prepare a platinum material with improved mechanical properties at high temperatures and reduce preparation costs and preparation time as compared with conventional methods by sequentially performing post processes of the porous sheet after easily manufacturing a porous sheet through the thermal spray coating process. A preparation method of an oxide dispersion strengthened platinum material using a thermal spray coating process comprises: a step(S1) of adding metal elements with a target composition to platinum, and vacuum melting the mixture to manufacture an ingot; a step(S2) of manufacturing the ingot into a wire through swaging and drawing; a step(S3) of thermal spray coating the wire in a graphite mold master to manufacture a porous thermal spray coated sheet; a step(S4) of separating the thermal spray coated sheet from the mold master, and subjecting the thermal spray coated sheet to an atmospheric heat treatment to remove a carbon sheet from the thermal spray coated sheet; a step(S5) of performing hot forging and heat treatment of the carbon sheet-removed thermal spray coated sheet to obtain a reinforced platinum material with a specific gravity near the theoretic specific gravity; and a step(S6) of performing cold rolling and heat treatment of the reinforced platinum material.

Description

Manufacturing method of the oxide dispersed platinum material using a thermal spray process

1 is a flow chart showing the overall flow of the method for producing an oxide dispersion-enhanced platinum material using the thermal spraying method according to the present invention.

The present invention relates to a method for producing a platinum material, and more particularly, to a method for producing an oxide dispersion-enhanced platinum material using a thermal spraying method.

In general, alloying is performed in which gold (Au), rhodium (Rh), and the like are added as reinforcing elements in order to improve mechanical properties of platinum. There is this.

In addition, in recent years, a platinum material dispersed using an oxide has been developed and used. Such a platinum material is known to have excellent creep characteristics even though it is maintained at a high temperature for a long time due to very low grain growth and strain. In addition, it is low cost compared to the platinum material of the existing gold (Au), rhodium (Rh) alloy, and has the advantage of having a long life at high temperature as well as thinning.

In the method of producing a platinum material in which the oxide is dispersed, a powder is manufactured by a wet method, and then a molded body is prepared by primary molding, cold isotropic compression molding (CIP), and the like, and is produced by sintering, hot working, and cold rolling. Ingots are melted and cast in the case by dry method, and then powdered by atomizing or arc spraying, pulverizing, degassing, oxidation treatment and hot press. And repeated heat treatment and the like are finally produced by hot working and cold working.

In addition, Patent Document No. 2006-0011939 discloses hot forging after heat treatment to remove carbon sheets after hot pressing to overcome the risk of collapse during hot forging of sintered articles in the production of platinum material. It is disclosed to carry out.

When the platinum material is manufactured by the above methods, the wet method has a shorter manufacturing time than the dry method, but has a low temperature characteristic. The dry method has a high temperature characteristic, but the manufacturing cost is high due to complicated processes such as powder preparation and powder pretreatment. There is a disadvantage that the manufacturing time is increased for a long time.

Therefore, in order to produce a platinum material having excellent high temperature strength by using conventionally known methods as described above, after producing an ingot by a dry method, powder production, degassing, oxidation treatment, hot press (by arc spraying) Hot press), repetitive heat treatment, hot working, cold working, etc. are required, as the complexity of the process increases the manufacturing cost and the time required for manufacturing.

However, in the case of manufacturing a porous plate material, not the conventional powder production as described above, many processes from powder production to sintering and hot press can be omitted. Therefore, after melting vacuum with platinum and an alloying element having a greater oxidizing power than platinum, it is made of wire by swaging, drawing, etc., a plate is manufactured by using a hot spray, and a post process is performed to manufacture a final plate. Platinum material can be produced in a short time.

Therefore, the present invention is designed to solve the above problems of the prior art, and is used as a device that is exposed to high temperatures for a long time, such as devices of glass-related industries, and mechanical properties at high temperatures such as high temperature strength and creep resistance of platinum materials. In the production of the improved platinum material, by applying the thermal spraying method, a porous sheet material is easily manufactured, followed by post-processing and the like, and the oxide dispersion strengthening type using the thermal spraying method, which can produce the platinum material in a shorter time than the conventional powder production. It is an object to provide a method for producing a platinum material.

Another object of the present invention is to provide a method for producing an oxide-dispersed platinum group material using a thermal spraying method using a thermal spraying method, which has a lower manufacturing cost and a shorter manufacturing time than the conventional method and improves mechanical properties at high temperatures.

In order to solve the above problems, according to the present invention, in the method for producing a platinum material, the step of vacuum melting by adding a metal element of the target composition to platinum, and sway the ingot produced in the vacuum melting step Manufacturing a porous sprayed plate by spraying the wire manufactured through the swaging and the wire onto a graphite mold master having a desired size; and manufacturing the porous sprayed plate. Separating the thermally sprayed plate material prepared in the mold master and removing the carbon sheet by queuing, and performing hot forging and heat treatment on the thermally sprayed plate material from which the carbon sheet has been removed. Cold rolling and heat treatment on the reinforced platinum material obtained by performing the step of hot forging and heat treatment. The method of manufacturing an oxide dispersion strengthened type spraying method using a platinum material, characterized in that configured to include a step of performing the re is provided.

In addition, according to the present invention, in the method for producing a platinum group material, adding a metal element of the target composition to the platinum group material by vacuum dissolution, and the ingot prepared in the vacuum dissolution step by wire through the swaging and drawing Fabricating the thermal sprayed plate material by spraying the wire manufactured through the swaging and drawing to a graphite mold master having a desired size, and manufacturing the porous thermal sprayed plate material Removing the carbon sheet by quenching after separating from the mold master, and performing hot forging and heat treatment on the thermally sprayed plate material from which the carbon sheet has been removed to obtain a reinforced platinum group material close to a theoretical weight; Cold rolling and heat treatment are performed on the reinforced platinum group material obtained by forging and heat treatment. The method of manufacturing an oxide dispersion strengthened platinum group-type materials by thermal spraying, characterized in that configured is provided, including the steps:

According to the manufacturing method of the oxide dispersion-enhanced platinum material using the thermal spraying method of the present invention as described above, the powder manufacturing step and the powder pretreatment step are omitted, so that the platinum material can be produced in a short time and close to the theoretical weight, It is excellent in the creep properties, and at the same time used in the glass industry can produce a platinum material that does not produce blister (blister) at 1400 ℃.

In addition, the thermal spraying method applied to this invention is a technique of changing a powder or a linear material into a molten liquid from a high temperature heat source, and colliding with a base material at high speed, and forming a quenching, coagulation | solidification, and a laminated film. Thick film formation becomes possible. In addition, the thermal spraying method requires heat sources such as a flame, arc, plasma, and the like having high energy density for heating and melting of materials, and thus, materials such as metals, ceramics, glass, and plastics are used. Can be used.

Therefore, in the case of manufacturing the platinum group material by such a thermal spraying method, it is possible to omit a large number of steps to solve the problems occurring during the powder manufacturing and control process during the manufacturing by the conventional method, so that the oxide dispersion-reinforced platinum group material plate in a short time It is possible to manufacture.

Hereinafter, a method of manufacturing an oxide dispersion-enhanced platinum material using the thermal spraying method according to the present invention will be described in detail with reference to the accompanying drawings.

Fig. 1 is a flowchart showing the overall flow of the method for producing an oxide dispersion-enhanced platinum material using the thermal spraying method of the present invention.

As shown in FIG. 1, first, a metal of a desired composition is added to platinum and vacuum-dissolved (step S1). At this time, the material to be injected into the thermal spraying apparatus can be either powder or wire, but when the powder is produced by the wet method, it is preferable to perform vacuum dissolution because the production time of the powder is long and it is difficult to control the target composition.

Moreover, as a metal material used for addition to a platinum material for dispersion strengthening, zirconium (Zr), samarium (Sm), yttrium (Y), europium (Eu), hafnium (Hf), etc. are mentioned, for example. Since these metal elements have a strong affinity with oxygen than platinum and have a characteristic of forming oxides in preference to platinum when contacted with oxygen, the process of removing the thermal spraying process and the carbon sheet during the following process will be described later. And by hot forging.

In the step (S1), the amount of the metal element for the alloy is preferably from 0.05wt% to 5wt%. This is because the dispersion strengthening effect cannot be obtained at less than 0.05 wt%, and if it exceeds 5 wt%, the dispersion strengthening by the remaining dispersed particles is increased and the workability is also lowered.

In this way, an ingot is manufactured through step S1, and a wire is manufactured to a size to be injected into the thermal spraying apparatus through a swaging and drawing process (step S2). In this case, the manufactured ingot is gradually reduced in cross-sectional area using a swaging machine composed of multiple stages, and finally, wires are manufactured to a thickness suitable for a thermal spraying apparatus through drawing.

Thereafter, by spraying the wire drawn in the step (S2), using a thermal spray to a graphite mold master of the target size prepared in advance to produce a porous thermal spraying plate material (step S3). At this time, the size of the master is produced in consideration of the thickness of the final product, and after the thermal spraying using a carbon sheet for easy separation between the sprayed layer and the mold, or by using a super-high temperature BN to suppress the reaction of the mold and the sprayed layer. The thickness of the thermal spray plate is determined in consideration of the subsequent processes such as hot forging and cold rolling, and about 10 to 200 mm is suitable.

In addition, in order to increase the dispersibility of alloying elements and affinity with oxygen during hot forging and heat treatment of the subsequent process, the sprayed layer should be composed of fine particles and porosity, which is the spraying speed, the spraying distance, the wire feeding speed, This can be done by controlling the speed of fraud and the like. In addition, as the gas used for high pressure spraying during spraying, for example, argon (Ar), nitrogen (N ₂ ), oxygen (O ₂ ), air (Air), etc. may be used. Most preferably, oxygen (O ₂ ) is used.

Next, after separating the mold master and the thermal spray plate material obtained through the step (S3), the carbon sheet is removed by a queuing process (step S4). As described above, in step S3, a carbon sheet is used to facilitate separation between the mold master and the thermal spray plate material, and the carbon sheet is removed through heat treatment for 2 to 3 hours at a temperature of 1300 ° C. or higher in the air. . In general, the carbon sheet is easily removed at a temperature of 1000 ° C. or higher, but in the present invention, heat treatment is performed at a higher temperature to promote oxidation of metal elements in addition to the purpose of removing the carbon sheet.

After that, hot forging and heat treatment are performed on the thermally sprayed plate having the carbon sheet removed in step S4 (S5). The hot forging temperature is performed at a temperature of 1200 ° C. or more, which is a general forging temperature of platinum. Through such hot forging, a specific gravity close to the theoretical weight is secured.

Here, as described in the description of the prior art, in the conventional known patent document 2006-0011939, in order to overcome the risk of collapse during hot forging of a sintered product in the production of platinum material (Hot Press) After performing the work, it is disclosed to perform hot forging after the heat treatment to remove the carbon sheet, but according to the present invention can skip the steps and proceed directly to the hot forging operation. In addition, after hot forging, the annealing process of heat-processing for about 1 hour is performed at the temperature of 1200 degreeC or more.

Subsequently, cold rolling and heat treatment are performed on the plate material hot-forged and heat-treated in the step S5 (step S6). As such, the purpose of introducing the processed tissue in step S6 is, firstly, for homogenization of the tissue by recrystallization through post-heat treatment, and secondly, for increasing the size through cold rolling. In this case, the reduction ratio is preferably 50% or more so that recrystallization may occur through subsequent heat treatment.

As such, when heat-treating the cold-rolled material in air for recrystallization for homogenization of the cold-rolled tissue, the heat-treatment temperature is most suitably heat-treated at 1200-1400 ° C. for 1 hour. This is because recrystallization is difficult when the temperature is lower than 1200 ° C., and coarsening of crystals may occur when the temperature is 1400 ° C. or higher.

As described above, by using the method for producing an oxide dispersion-enhanced platinum material using the thermal spraying method according to the present invention, the oxide dispersion-enhanced platinum group which has a lower manufacturing cost and a shorter manufacturing time and improves mechanical properties at high temperatures as compared with the prior art. Material can be prepared.

EXAMPLE

Next, specific examples of the method for producing an oxide dispersion-enhanced platinum material using the thermal spraying method according to the present invention as described above will be described below.

First, 5 kg of a platinum-zirconium alloy ingot containing 0.3 wt% of zirconium was prepared using a vacuum induction melting furnace.

Thereafter, the produced ingot is made of a wire through a swaging machine made of multistage and drawn, wherein the diameter of the wire is 1.2 mmφ.

In this way, the final wire is injected into an arc spraying apparatus, melted by arc discharge, and then sprayed to a pre-fabricated carbon sheet and a graphite mold master coated with ultra high temperature BN to a thickness of about 50 mm.

At this time, the size of the master is 30mm (width) × 60mm (length) × 20mm (thickness), and the sprayed condition is in the range of 0.05 ~ 10㎛ from the result of the particle size analysis by performing a thermal spray test on distilled water through a preliminary experiment The particle size of the powder is controlled to have a size of 5 μm or less, and then the same conditions are performed.

Next, after the platinum-zirconium plate material is removed from the graphite mold master, the carbon sheet is removed and oxidized by queuing at 1300 ° C. for 3 hours.

Subsequently, as described above, the sheet obtained by removing the carbon sheet was subjected to hot forging at 1300 ° C. to have a relative specific gravity close to 100% of the theoretical specific ratio, and then, by heat treatment and cold rolling, the thickness was finally 1 mm. To prepare a platinum material after the heat treatment for 1 hour at 1300 ℃ in the air as a final heat treatment.

The specimens subjected to the heat treatment after cold working thus obtained were subjected to heat treatment at 1200 ° C., 1400 ° C., and 1600 ° C. for 1 hour, respectively, and then to evaluate the presence of blisters and the mechanical properties at high temperature. Creep test was carried out at ℃ and the results are shown in Table 1.

Blister after heat treatment Creep Strength Mpa (300 hours at 1400 ℃) 1200 ℃ 1400 ℃ 1600 ℃ Example none none none 10.1 Existing reporting example (GHT-Pt) none none none 10.3 Existing reporting example (ZGS-Pt) none none none 8.5 Industrial Pure Platinum (Pt) none none none 1.5

As shown in Table 1, all of the heat-treated specimens were not found blister, it can be confirmed that the creep resistance in the creep strength almost similar to the conventional platinum material.

Therefore, from all these results, it can be seen that the platinum material produced by the method of producing an oxide dispersion-enhanced platinum material using the thermal spraying method according to the present invention has very sound characteristics.

As mentioned above, the present invention has been described through the embodiments of the present invention as described above, but the present invention is not limited to the above embodiments, but is necessary for design by those skilled in the art to which the present invention pertains. It is a matter of course that various changes and modifications can be made without departing from the spirit of the present invention according to other factors.

As described above, according to the present invention, after vacuum-dissolving a metal of the target composition in platinum, and producing a wire by swaging, drawing, etc., a porous thermal spray plate material is manufactured by using arc spraying on a pre-fabricated graphite mold master. Then, through the process of hot forging, cold rolling and heat treatment, it is possible to produce a platinum material having the same characteristics as the conventional platinum material in a less process than the conventional method.

That is, according to the present invention, by manufacturing a plate directly by the thermal spraying method, by omission of the powder preparation and powder pretreatment process, the manufacturing process is much shorter than the conventional platinum material in manufacturing the platinum material and the manufacturing cost is reduced accordingly. The platinum material having the same characteristics as that of the conventional platinum material can be produced while being reduced.

In addition, according to the present invention, by directly manufacturing a plate using a thermal spraying method, by omission of powder preparation and powder pretreatment, etc., the manufacturing process of the platinum material is much shorter than that of the conventional method, and the manufacturing cost is reduced accordingly. At the same time, it is possible to provide a method for producing an oxide-dispersed platinum material using a thermal spraying method that can produce a platinum material having properties equivalent to those of a platinum material manufactured by a conventional manufacturing method.

In addition, according to the present invention, by directly manufacturing a plate using a thermal spraying method, by omission of the powder preparation and powder pretreatment process, the manufacturing process is much shorter than the conventional method in the production method of the platinum group material and the manufacturing cost is reduced accordingly. It is possible to provide a platinum group material which can be lowered and exhibit the same characteristics as that of a platinum group material produced by a conventional production method, and can also provide a method for producing an oxide dispersion-enhanced platinum group using a thermal spraying method capable of producing such a platinum group material. Can be.

Claims (15)

In the manufacturing method of the platinum material, Vacuum melting by adding a metal element of the objective composition to platinum; Ingot manufactured in the vacuum melting step (Ingot) and the step of producing a wire through the swaging and drawing; Manufacturing a porous sprayed plate material by spraying the wire manufactured through the swaging and drawing on a graphite mold master having a desired size; Separating the thermal sprayed plate material prepared in the step of manufacturing the porous thermal sprayed plate material from the mold master and removing the carbon sheet by queue treatment; Performing hot forging and heat treatment on the thermally sprayed plate material from which the carbon sheet is removed to obtain a reinforced platinum material close to a theoretical weight; Cold rolling and heat-treating the reinforced platinum material obtained by performing the hot forging and heat treatment, characterized in that it comprises a step of producing an oxide dispersed strengthening platinum material using a thermal spraying method. The method of claim 1, The metal element added in the vacuum melting step is at least one of zirconium (Zr) samarium (Sm), yttrium (Y), europium (Eu), and hafnium (Hf). Method for producing type platinum material. The method of claim 2, The amount of the added metal element is about 0.05wt% ~ 5wt% method of producing an oxide dispersion-enhanced platinum material using the thermal spraying method. The method of claim 1, In the step of producing the thermal spray plate, the gas used during the thermal spraying is one of argon (Ar), nitrogen (N ₂ ), oxygen (O ₂ ), air (Air), The size of the powder laminated on the thermal spray plate during the spraying is in the range of 0.05 ~ 10㎛, the central particle size is 5㎛ or less, The thickness of the thermal spray plate material is characterized in that 10 ~ 200mm method of producing an oxide dispersion-enhanced platinum material using the thermal spraying method. The method of claim 1, In the step of removing the carbon sheet, the queue treatment is a method of producing an oxide dispersion-enhanced platinum material using a thermal spraying method characterized in that the heat treatment for 2 to 3 hours at a temperature of 1300 ℃ or more. The method of claim 1, In the step of obtaining the reinforced platinum material, the hot forging is performed at a temperature of 1200 ° C. or more, which is a forging temperature of general platinum, and the heat treatment is performed by thermal spraying for 1 hour at a temperature of 1200 ° C. or more. Method for producing type platinum material. The method of claim 1, In the cold rolling and heat treatment step, the cold rolling is carried out so that the reduction ratio is 50% or more, and the heat treatment is oxide dispersion strengthened platinum using a spraying method, characterized in that it is configured to be carried out for 1 hour at 1200 ~ 1400 ℃. Method of manufacturing the material. In the method for producing a platinum group material, Vacuum melting by adding a metal element of the target composition to the platinum group material, Manufacturing the ingot prepared in the vacuum melting step into a wire through swaging and drawing; Manufacturing a porous sprayed plate material by spraying the wire manufactured through the swaging and drawing on a graphite mold master having a desired size; Separating the thermal sprayed plate material prepared in the step of manufacturing the porous thermal sprayed plate material from the mold master and removing the carbon sheet by queue treatment; Performing hot forging and heat treatment on the thermally sprayed plate material from which the carbon sheet is removed to obtain a reinforced platinum group material close to a theoretical weight; Cold rolling and heat-treating the reinforced platinum group material obtained by performing the hot forging and heat treatment, characterized in that it comprises a step of producing an oxide dispersed strengthening platinum group material using a thermal spraying method. The method of claim 8. The platinum group material is platinum (Pt), palladium (Pd), osmium (Os), rhodium (Rh) any one of the method of producing an oxide dispersion-enhanced platinum group material using a thermal spraying method. The method of claim 8, The metal element added in the vacuum melting step is at least one of zirconium (Zr) samarium (Sm), yttrium (Y), europium (Eu), and hafnium (Hf). Method for producing a type platinum group material. The method of claim 10, The amount of the added metal element is about 0.05wt% ~ 5wt% method of producing an oxide dispersion-enhanced platinum group material using the thermal spraying method. The method of claim 8, In the step of producing the thermal spray plate, the gas used during the thermal spraying is one of argon (Ar), nitrogen (N ₂ ), oxygen (O ₂ ), air (Air), The size of the powder laminated on the thermal spray plate during the spraying is in the range of 0.05 ~ 10㎛, the central particle size is 5㎛ or less, The thickness of the thermal spray plate is 10 ~ 200mm characterized in that the method of producing an oxide dispersion-enhanced platinum group material using the thermal spraying method. The method of claim 8, In the step of removing the carbon sheet, the queue treatment is a method of producing an oxide dispersion-enhanced platinum group material using the thermal spraying method characterized in that the heat treatment for 2 to 3 hours at a temperature of 1300 ℃ or more. The method of claim 8, In the step of obtaining the reinforced platinum material, the hot forging is performed at a temperature of 1200 ° C. or more, which is a forging temperature of general platinum, and the heat treatment is performed by thermal spraying for 1 hour at a temperature of 1200 ° C. or more. Method for producing a type platinum group material. The method of claim 8, In the cold rolling and heat treatment step, the cold rolling is carried out so that the reduction ratio is 50% or more, and the heat treatment is carried out for 1 hour at 1200 to 1400 ° C. Method of manufacturing the material.

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