KR20170038274A

KR20170038274A - Zr or Zr-based alloy powders for Production Method and thereof Zr or Zr-based alloy powders

Info

Publication number: KR20170038274A
Application number: KR1020150137400A
Authority: KR
Inventors: 김규진
Original assignee: 티엠나노테크 주식회사
Priority date: 2015-09-30
Filing date: 2015-09-30
Publication date: 2017-04-07
Also published as: KR101776111B1

Abstract

According to the present invention, by using a complex gas-water atomizing method; zirconium and zirconium alloy powders having an average particle diameter of 10 m or less is able to be prepared; and an oxygen and nitrogen content in the powder are equal or less than 1000 ppm respectively, which are very low. As a condition for the present invention, a nozzle diameter of a tundish should be 4-10 mm; an injection pressure of an inert gas should be 20-50 bar, and a quantity of injection should be in a range of 10-30 liter/min when a first injection is performed; and a water pressure should be in a range of 300-1000 bar and a quantity of injection should be in a range of 200-700 liter/min when a second injection is performed.

Description

[0001] The present invention relates to a method for producing zirconium powder or zirconium alloy powder and a zirconium powder or zirconium alloy powder,

The present invention is applied to special applications such as 3D printer and MIM (mold injection molding) requiring high purity by gas-water complex gas-water atomizing method while applying a pressure of 2 to 3 bar on the tundish A zirconium powder or zirconium alloy powder having an average particle diameter of 10 mu m or less and a zirconium powder or a zirconium alloy powder characterized by being produced by such a production method.

Zirconium is the ninth most abundant metal on the planet. It has superior corrosion resistance than any metal, and its mechanical properties and thermal conductivity are similar to those of conventional SUS and Ti materials. Therefore, , And is widely used in petrochemical industry parts.

At present, the production of general zirconium powder or zirconium alloy powder is made by chemical reaction, and more than 98% of the world applies this method.

That is, zirconium powder or zirconium alloy powder produced by a chemical reaction is produced by reacting gaseous zirconium tetrachloride (ZrCl ₄ ) with molten magnesium to prepare a metal sponge of zirconium and zirconium alloy, (Hydrogenation-dehydrogenation process), which is a method of preparing zirconium powder or zirconium alloy fine powder by forming zirconium oxide (ZrH ₂ ), pulverizing it into a powder form and finally dehydrogenating it, It is mainly applied.

However, such a hydrogenation-dehydrogenation process requires 1) a multi-step process including the production of a metal sponge, 2) involvement of hydrogen gas in the reaction, 3) the shape of the crushed powder is square, And 4) the risk of explosion at the time of pulverization.

Other methods for producing zirconium powder or zirconium alloy powder are disclosed in Korean Patent Laid-Open Publication No. 10-0372226 (published on Mar. 02, 2004), page 3, There is a process.

However, such a gas injection process has a technical difficulty in melting a metal having a high melting point such as zirconium and easily absorbing oxygen, nitrogen and hydrogen at a high temperature, and a zirconium or zirconium alloy has a high viscosity in a molten state The nozzle of the molten metal must be at least twice as large as that of the iron-based metal having a low viscosity, and thus, even in the case of the powder that has been successfully produced by the gas injection process, the particle size is usually as large as several hundred microns It is difficult to apply it to general powder molding and powder injection molding, so that there is practically no practical application.

On the other hand, it is possible to produce fine powder of 30 탆 or less by application of a high-pressure water pressure method of 300 bar or more. However, in the case of producing zirconium powder or zirconium alloy powder, Therefore, practical application is difficult.

Korean Patent Registration No. 10-0372226 (2003. 02. 14th Announcement), Summary, page 3, and Drawing 1

The present invention is characterized in that the oxygen content in the prepared zirconium powder or zirconium alloy powder is lowered to 1000 ppm or less and the average particle diameter of the zirconium powder or zirconium alloy powder is 10 탆 or less in order to solve the above- And a zirconium powder or a zirconium alloy powder according to the method of producing the zirconium powder or zirconium alloy powder.

The method according to the present invention is the same method as that of the " method of producing stainless steel and titanium alloy powder " by the applicant of the present invention and is described in Korean Patent Application 10-2014-0101638

According to the present invention, in order to solve the above-mentioned conventional problems, it has been proposed to provide the molten metal with flowability by applying a pressure of 1.5 to 3 bar to the upper part of the zirconium or zirconium alloy melt, Characterized in that the oxygen content in the zirconium powder or zirconium alloy powder produced by changing the content and the pressure of the gas-water by the composite injection nozzle of water is 1000ppm or less and the average particle diameter of the powder is 10μm or less Or a zirconium alloy powder and a zirconium powder or a zirconium alloy powder.

The zirconium powder or the zirconium alloy powder having an average particle diameter of 10 mu m or less and having a low oxygen content and which was impossible to produce by the conventional single water spraying method or gas spraying method by the gas- Can be stably manufactured, so that it can be applied to special applications such as 3D-printer and MIM (metal injection molding).

1 is a view showing a gas-water composite spraying apparatus according to the present invention.

As shown in the figure, the gas-water composite spraying apparatus for producing zirconium powder or zirconium alloy powder according to the present invention is as follows.

A tundish main body 10 and a tundish crucible 30 for storing the molten zirconium or zirconium alloy melt 20 dissolved in a vacuum induction melting furnace (not shown) A tundish heating device 40 for heating the dish crucible 30 and a tundish heating device 40 for heating the crucible 30 to form a melted zirconium or zirconium alloy melt 20 at the bottom of the tundish crucible 30 A tundish 60 connected to a lower portion of the tundish main body 10 and connected to the tundish nozzle 50 to supply the molten metal to the tundish nozzle 50; The upper portion of the injector main body 70 is connected to an upper portion of the injector main body 70 through the molten metal 20 supplied from the tundish nozzle 50, And the injector nozzle 80 for the combined injection do.

The injector nozzle 80 is a double annular type primary and secondary nozzles 90 and 100. The primary nozzle 90 performs gas injection processing with an inert gas (for example, argon, nitrogen) at a high pressure of 20 bar or more, The secondary nozzle 100 is subjected to water jetting with high-pressure water as described above.

An inert gas (for example, argon, nitrogen or the like) is injected into the vacuum induction melting furnace to maintain the atmospheric pressure of the molten metal 20 of zirconium or zirconium alloy at 1.5 to 3 bar.

The tundish crucible 30 of the tundish main body 10 is preheated to 70% or more of the melting temperature by the tundish heating device 40 provided in the vacuum induction melting furnace.

The tundish nozzle 50 is formed to have a diameter of 4 to 10 mm and a molten metal 20 of zirconium or zirconium alloy is discharged toward the injector main body 70 at a constant speed to form a double gas- The spraying process is performed by the process. The reason for this is that zirconium is easily oxidized easily at high temperature because it is sprayed first with gas rather than water.

The average particle size of the zirconium powder or the zirconium alloy powder to be produced and the oxygen content in the powder are controlled so that the diameter of the tundish nozzle 50 and the diameter of the primary and secondary nozzles of the double- The pressure of gas and water jetted from the nozzles 90 and 100, and the discharge amount of gas and water to be injected.

The temperature of the hot water of the zirconium or zirconium alloy melt 20 spouted into the tundish crucible 30 in the vacuum induction melting furnace is determined by the diameter of the tundish nozzle 50 and the pressure of the molten metal. Is required to have a superheated temperature in the range of 5 to 15% of the melting temperature of the zirconium and zirconium alloys. When the melting temperature is lower than 5%, the tundish nozzle 50 easily clogs. When the melting temperature is higher than 15%, the lifetime of the high melting point tundish crucible 30 is greatly reduced.

The pressure of the upper portion of the zirconium or zirconium alloy melt 20 is suitably 1.5 to 3 bar and the flowability of the molten metal 20 is significantly lowered below 1.5 bar. The excessive use of the gas and the production cost of the device for preventing the gas leakage are excessive.

Ar gas and nitrogen, which are inert gases, are suitable for the gas to be sprayed from the primary nozzle 90 of the injector nozzle 80, and the operating pressure is 20 to 50 bar and the used amount is 10 to 30 liter / min. When the working pressure is 20 bar or less and 10 liter / min or less, the initial atomization of the powder is impossible. When the operating pressure is 50 bar or more and 30 liter / min or more, the gas consumption is excessively increased and the cost of manufacturing the gas device is increased.

When water is injected from the secondary nozzle 100 of the injector nozzle 80, the water to be used determines the average particle size of the final powder, and the operating pressure is in the range of 300 to 1000 bar and the used amount is in the range of 200 to 700 liter / min . When the operating pressure is below 300 bar and 200 liter / min, the average particle size of the powder is coarse (larger particle size) than 15 μm, and when the operating pressure exceeds 1000 bar and 700 liter / min, the water consumption is excessively large and the apparatus cost becomes large.

In addition, the diameter of the tundish nozzle 50 in the tundish main body 10 is suitably 4 to 10 mm. When the diameter of the tundish nozzle 50 is less than 4 mm, the productivity is decreased. Further, the tundish nozzle 50 is easily clogged. When the diameter of the tundish nozzle 50 is 10 mm or more, The particle becomes large).

The process for producing a zirconium powder or a zirconium alloy powder by the gas-water composite spraying apparatus of FIG. 1 according to the present invention is as follows.

First, a step (S100) of injecting an inert gas (for example, argon, nitrogen, etc.) into the vacuum induction melting furnace to maintain the atmospheric pressure of the molten zirconium or zirconium alloy dissolved in the vacuum induction furnace at 1.5 to 3 bar,

The tundish crucible 30 of the tundish main body 10 preheated to 70% or more of the melting temperature by the tundish heating device 40 connected to the vacuum induction melting furnace is supplied with the molten metal 20 of the zirconium or zirconium alloy (S200) of tapping,

The stopper 60 blocking the tundish nozzle 50 is removed and the molten metal 20 is supplied to the atomizer body 70 at a constant speed through the tundish nozzle 50 having a diameter of 4 to 10 mm, (S300), and a step

The molten metal 20 emitted from the tundish nozzle 50 is first subjected to gas injection processing with an inert gas (for example, argon, nitrogen) at a high pressure of 20 bar or more by the primary nozzle 90, (S400) of grinding and cooling,

The powder 200 is subjected to water spraying as secondary water at a high pressure of 300 bar or more by secondary nozzle 100 in succession to the step (S400) of spraying and pulverizing and cooling the primary nozzle 90, (S500) of pulverizing and cooling the mixture,

The powder 110 pulverized and cooled into fine particles by the injector nozzle 80 is cooled in the injector main body 80 and then collected in the lower part and dried to produce final zirconium powder or zirconium alloy powder S600 ).

Hereinafter, embodiments of the present invention will be described in detail.

Best Mode for Carrying Out the Invention [

(Example 1)

100 kg of zirconium ingots having a purity of 99.8% was melted in a vacuum induction furnace of 10 ^-2 Torr and heated to 2,200 ° C. Then, Ar gas was injected into the vacuum induction melting furnace to adjust the pressure in the vacuum induction melting furnace to 2 bar. The zirconium or zirconium alloy melt 20 dissolved in the tundish crucible 30 of the tundish main body 10 preheated to 1,500 캜 was boiled and then the stopper blocking the tundish nozzle having a diameter of 6 mm was lifted The molten metal 20 is flowed to the atomizer main body 70 at a constant speed to perform a complex double gas-water spray process.

The argon gas pressure during the first gas injection was 30 bar, the gas injection amount was 15 liter / min, the water pressure during the second injection was 500 bar, and the water injection amount was 450 liter / min. The pulverized and cooled fine powder (110) is subjected to a drying treatment to produce a final powder. The properties of the powder thus produced are shown in Table 1.

Here, the average particle size of the powder was measured by a particle size analyzer, the phase structure of the powder was measured by X-ray diffraction, and the oxygen and nitrogen contents in the powder were measured as an oxygen / hydrogen / nitrogen analyzer.

(Example 2)

Except that 100 kg of the ingot of Zr ₄₅ Ti ₃₁ Cu ₁₅ Ni ₉ alloy composition (atomic%) was melted in a vacuum induction melting furnace and heated to 1850 ° C. and the molten metal 20 was injected into the tundish crucible 30 preheated at 1400 ° C. The procedure of Example 1 was repeated. Table 1 shows various properties of the powder thus prepared.

(Example 3)

Except that 100 kg of the ingot of Zr ₄₈ Cu ₃₅ Ag ₈ Al ₉ alloy composition (atomic%) was melted in a vacuum induction melting furnace and heated to 1600 캜 and the molten metal 20 was injected into the tundish crucible 30 preheated at 1400 캜 The procedure of Example 1 was repeated. Table 1 shows various properties of the powder thus prepared.

(Example 4)

Except that the diameters of the tundish nozzle 50 of the tundish main body 10 were set to 4 and 8 mm, respectively. Table 1 shows various properties of the powder thus prepared.

(Example 5)

The same procedure as in Example 1 was carried out except that the injection amount of argon gas injected from the primary nozzle 90 was 10 and 30 liter / min. Table 1 shows various properties of the powder thus prepared.

(Example 6)

The procedure of Example 1 was repeated except that the pressure of water injected from the secondary nozzle 100 was 300 bar. Table 1 shows various properties of the powder thus prepared.

(Example 7)

The same procedure as in Example 1 was carried out except that the injection amount of water injected from the secondary nozzle 100 was 200 liter / min. Table 1 shows various properties of the powder thus prepared.

(Example 8)

The same procedure as in Example 2 was carried out except that the gas used for gas injection from the primary nozzle 90 was nitrogen. Table 1 shows various properties of the powder thus prepared.

(Comparative Example 1)

Example 2 was carried out in the same manner as in Example 2, except that only the gas jet from the primary nozzle 90 was used under the conditions of Example 2, and no secondary moisture was used. Table 1 shows various properties of the powder thus prepared.

(Comparative Example 2)

The same procedure as in Example 2 was carried out except that only the water jetting by the secondary nozzle 100 was used under the condition of Example 2 without using the primary gas jetting. Table 1 shows the properties of the powder thus prepared.

(Comparative Example 3)

The procedure of Example 1 was repeated except that the diameter of the tundish nozzle 50 was 12 mm. Table 1 shows various properties of the powder thus prepared.

(Comparative Example 4)

The same procedure as in Example 1 was carried out except that the argon gas pressure at the time of gas injection by the primary nozzle 90 was 15 bar. Table 1 shows various properties of the powder thus prepared.

(Comparative Example 5)

The same procedure as in Example 1 was carried out except that the amount of argon gas injection at the time of gas injection by the primary nozzle 90 was 8 liter / min. Table 1 shows various properties of the powder thus prepared.

(Comparative Example 6)

The same procedure as in Example 1 was carried out except that the injection pressure of water at the time of water wetting by the secondary nozzle 100 was set to 250 bar. Table 1 shows the zener characteristics of the powder thus prepared.

(Comparative Example 7)

The same procedure as in Example 1 was carried out except that the amount of water sprayed by the secondary nozzle 100 was 180 liter / min. Table 1 shows various properties of the powder thus prepared.

Condition
number alloy Tundish nozzle diameter
(mm) gas water Powder
rescue Average particle size () Oxygen and nitrogen content (ppm) pressure
(bar) Injection quantity
(liter / min) pressure
(bar) Injection quantity
(liter / min) Oxygen nitrogen Example 1 Pure Zr 6 30 15 500 450 decision 3 1300 - Example 2 Zr ₄₅ Ti ₃₁ Cu ₁₅ Ni ₉ 6 30 15 500 450 Amorphous 4 750 - Example 3 Zr ₄₈ Cu ₃₅ Ag ₈ Al ₉ 6 30 15 500 450 Amorphous 3 730 - Example 4 Pure Zr 4 30 15 500 450 decision One 1410 - 8 30 15 500 450 decision 6 1240 - Example 5 Pure Zr 6 30 10 500 450 decision 3 1550 - 6 30 30 500 450 decision 3 980 - Example 6 Pure Zr 6 30 30 300 450 decision 7 720 - Example 7 Pure Zr 6 30 30 500 200 decision 9 690 - Example 8 Zr ₄₅ Ti ₃₁ Cu ₁₅ Ni ₉ 6 30 15 500 450 Amorphous 3 670 650 Comparative Example 1 Zr ₄₅ Ti ₃₁ Cu ₁₅ Ni ₉ 6 30 15 - - Amorphous + crystal 125 340 - Comparative Example 2 Zr ₄₅ Ti ₃₁ Cu ₁₅ Ni ₉ 6 - - 500 450 Amorphous 10 2500 - Comparative Example 3 Pure Zr 12 30 15 500 450 decision 85 630 - Comparative Example 4 Pure Zr 6 15 15 500 450 decision 21 760 - Comparative Example 5 Pure Zr 6 30 8 500 450 decision 35 1100 - Comparative Example 6 Pure Zr 6 30 15 250 450 decision 40 800 - Comparative Example 7 Pure Zr 6 30 15 500 180 decision 15 650 -

Here, as shown in the embodiment of Table 1, by applying the gas-water composite spraying method, it is possible to produce a metal material such as a zirconium or zirconium alloy having high viscosity at the time of melting by the conventional gas spraying method, It is possible to produce powders having an average particle diameter of not more than 10 μm and the oxygen content in the powder is as low as not more than 1000 ppm, which is not significantly different from the gas jet method. For this purpose, the diameter of the tundish nozzle 50 should be 4 to 10 mm. When the gas is injected by the primary nozzle 90, the injection pressure of the inert gas is 20 to 50 bar, the injection amount is 10 to 30 liter / min, and the water pressure should be in the range of 300 to 1000 bar and the injection amount should be in the range of 200 to 700 liter / min at the time of water leakage by the secondary nozzle (100).

On the other hand, as in the case of Comparative Example 1 in Table 1, when only the gas injection from the primary nozzle 90 was performed under the conditions of Example 2, the powder particle size was coarse (larger powder particles) And the water content in the powder is drastically increased in the case of performing only water jetting by the secondary nozzle 100 without using the primary gas jet as in the result of Comparative Example 2 in Table 1. [

The present invention relates to a 3D printer and a mold injection molding (MIM) which require high purity by applying a complex gas-water atomizing method of gas and water under a pressure of 1.5 to 3 bar on the tundish To a process for producing zirconium and zirconium alloy powders having an average particle diameter of 10 탆 or less.

10: tundish body 20: molten metal
30: tundish crucible 40: tundish heating device
50: tundish nozzle 60: stopper
70: atomizer body 80: injector nozzle
90: Primary nozzle 100: Secondary nozzle
110: Powder
ppm: the concentration of the solution in units of one millionth
bar: unit of barometric pressure

Claims

Characterized in that zirconium or zirconium alloy is produced by a powder having an average particle diameter of 10 m or less and a high purity by an inert gas such as argon and nitrogen and a gas-water spray with water. Manufacturing method

The method according to claim 1,
Characterized in that the oxygen content in the powder to be produced is 1,000 ppm or less and the nitrogen content is 1,000 ppm or less.

The method according to claim 1,
In the composite spraying method, the diameter of the tundish nozzle is 4 to 10 mm, the injection pressure of the inert gas is 20 to 50 bar, the injection amount is 10 to 30 l / min, the pressure of the water is 300 to 1000 bar, and the injection amount is in the range of 200 to 700 liter / min at the time of the second water flow.

A zirconium powder or zirconium alloy powder according to any one of claims 1 to 3, characterized in that it is produced by a process for producing a zirconium powder or a zirconium alloy powder

A tundish body;
A tundish crucible inside the tundish main body for storing a molten zirconium or zirconium alloy dissolved in a vacuum induction melting furnace;
A tundish heating device connected to the vacuum induction melting furnace to heat the tandish crucible;
A tundish nozzle formed below the tundish crucible to supply the molten zirconium or zirconium alloy melt to the lower injector body;
A stopper for blocking the tundish nozzle;
An injector main body formed at a lower portion of the tundish main body for spraying the molten metal supplied from the tundish nozzle at a constant speed;
Wherein the upper portion of the injector main body is formed with an injector nozzle for injecting the molten metal supplied from the tundish nozzle with a gas-water mist, the injector nozzle comprising a gas-water spray gun for producing a zirconium powder or a zirconium alloy powder

6. The sprayer according to claim 5,
Characterized in that the primary and secondary nozzles of the double annular type are formed by a primary nozzle for performing a gas injection process with an inert gas having a high pressure of 20 bar or more and a secondary nozzle for performing a water injection process with water having a high pressure of 300 bar or more, Or zirconium alloy powder for producing a gas-water mist composite spraying device

The method of claim 5,
Wherein the inert gas is injected into the vacuum induction melting furnace to maintain the atmospheric pressure of the molten metal of zirconium or zirconium alloy at 1.5 to 3 bar. The zirconium powder or zirconium alloy powder

A zirconium powder or zirconium alloy powder according to any one of claims 5 to 7, characterized in that it is produced by a gas-water composite spraying apparatus for producing a zirconium powder or a zirconium alloy powder

A method for producing a zirconium powder or a zirconium alloy powder,
A step (S100) of injecting an inert gas into the vacuum induction melting furnace to maintain the atmospheric pressure of the molten zirconium or zirconium alloy dissolved in the vacuum induction furnace at 1.5 to 3 bar,
(S200) tapping the molten zirconium or zirconium alloy into the tundish crucible of the tundish main body preheated to 70% or more of the melting temperature by the tundish heating device connected to the vacuum induction melting furnace,
Removing the stopper blocking the tundish nozzle to discharge the molten metal to the main body at a constant speed through a tundish nozzle having a diameter of 4 to 10 mm (S300)
(S400) of subjecting the molten metal discharged from the tundish nozzle to a gas injection treatment with an inert gas having a high pressure of 20 bar or more by means of a primary nozzle, thereby pulverizing and cooling the molten metal;
(S500) of spraying and pulverizing the fine particles by high-pressure water having a pressure higher than 300 bar by secondary nozzles in succession to the step (S400) of spraying and pulverizing and cooling the primary nozzle ,
(S600) a step of cooling the powder pulverized and cooled by the sprayer nozzle to cool the powder in the injector body, collecting the powder in the lower part and then drying the powder to prepare a final zirconium powder or zirconium alloy powder. Process for producing powder or zirconium alloy powder

The zirconium powder or the zirconium alloy powder according to claim 9, which is produced by the method for producing a zirconium powder or a zirconium alloy powder