KR20160010874A - Process for manufacturing metal containing powder - Google Patents

Abstract

The present invention provides a process for preparing a mixture comprising: a) mixing at least one metal oxide with Ca, Mg, calcium hydride, magnesium hydroxide or a mixture thereof in granular or powder form to form a mixture; b) maintaining said mixture at a temperature between 1000 ° C and 1500 ° C for 1 to 10 hours under an atmosphere of H ₂ ; And then c) recovering the powder containing the metal. In one embodiment, the metal hydroxide powder is recovered. In another embodiment, the process comprises the steps b) and c) of: d) converting the H ₂ atmosphere to an Ar atmosphere and maintaining the mixture under this atmosphere for a period of 20 minutes to 5 hours; Followed by e) cooling under an Ar atmosphere, wherein the metal powder is recovered in step c).

Description

PROCESS FOR MANUFACTURING METAL CONTAINING POWDER [0002]

The present invention utilizes certain reducing agents and specific reducing conditions to perform a reduction reaction of the metal oxides under a hydrogen gas protection, preferably by a simplified and cost-effective process, whereby metal powders, metal alloy powders , Intermetallic powders and / or hydride powders of the same. BACKGROUND OF THE INVENTION

Powder metallurgical (PM) technologies are well established routes for the effective production of complex metal based components. These techniques are commonly used in applications where iron based alloys, stainless steel, copper or nickel are required. However, the use of PM technologies which require materials such as titanium, chromium and tantalum has hitherto been limited due to the lack of availability of high quality corresponding powders.

Among the advanced materials are titanium metal base alloys and non-titanium metal based alloy powders which are critical to performance improvements and have high strength to weight ratio, good ductility and fracture toughness ), High corrosion resistance, and high melting point, which properties enable these alloys and powders to be used in the aerospace, chemical treatment, construction, and terrestrial systems, Making them important engineering materials for a number of applications. However, the main problem with titanium-based materials is that they are more expensive than competitive materials.

The present invention relates to the cost-effective production of metal powders, metal alloy powders, intermetallic powders and / or hydride powders thereof resulting in a high level of purity.

A conventional method of producing titanium alloy powders includes the steps of producing a titanium sponge by the Kroll process today, and vacuum arc melting the sponge followed by gas atomization. The crawling process involves the reaction of TiO ₂ with carbon under a chlorine gas at a temperature of about 800 ° C, thereby forming titanium chloride, TiCl ₄ .

The TiCl ₄ produced in this reaction is in the form of a liquid and must first be purified by distillation. This means that these processes are complex and use products that are difficult to handle, such as Mg and / or chlorine.

There are a number of attempts to produce titanium alloys in a more cost-effective manner, but require the use of more than one heat treatment step that lasts for several hours so far.

US 6,264, 719 discloses a process for the production of Al ₂ O ₃ in a Ti-rich metal or intermetallic phase, Discloses a method of producing a titanium-alumina composite resulting in the formation of particles.

JP 05299216 relates to the production of a rare earth based alloy magnetic material in which a rare earth oxide, a reducing agent and a metal are mixed and a reduction-diffusion reaction treatment is carried out to produce hydrogen- Described is how a cake-like reaction product that is treated and obtained in a reducing atmosphere is cooled. The reducing atmosphere is converted to an inert gas atmosphere when the cake-like reaction product is cooled. This conversion is carried out in a temperature window of 770 to 870 캜. The conversion treatment in this particular temperature window is said to result in a rare earth alloy product with good magnetic properties. In particular, it is important that the conversion treatment in this temperature window ensures that the product does not contain any undesired metal hydride products. There is no suggestion that any intermediate metal hydride product that can be formed during the reduction step has any useful properties.

WO2008 / 010733 describes a process for producing titanium alloy powders. TiO ₂ and Al powder are mixed and heat treated to form a TiAl / Al ₂ O ₃ metal matrix ceramic composite material in the first heat treatment step. The complex is with a CaH ₂ is reduced further in the second heat treatment step.

Attempts have also been made to produce various metal powders from metal oxides of various metal powders by using a so-called self-ignition synthesis method (Akiyama et al.). These methods usually result in products of low purity.

Consequently, there is still a need for a more cost-effective process for producing high-purity high-quality metal powders, metal alloy powders, intermetallic powders and / or hydride powders thereof.

The present invention is based on the recognition that it is possible to completely reduce metal oxides under a hydrogen atmosphere using calcium and / or calcium hydride granules or powders to obtain a high proportion of pure metal or metal alloy powders at the specified temperature . Surprisingly, the process of the present invention allows excellent control over reaction conditions, particularly in the context of the preferred metal oxides discussed herein, which means that there is no need to take additional steps that can be used in conventional methods . Such additional steps include providing a "buffer" material that does not contribute to the reaction step to act as a buffer during heat uptake / generation to avoid a sharp rise / fall in temperature. The process of the present invention also enables the production of metal powders, metal alloy powders, intermetallic powders and / or hydride powders thereof having a high quality especially in terms of purity and particle size distribution. The process can be applied to the production of a wide range of metal-containing powders such as metal powders, metal hydride powders, and / or metal alloy powders.

As starting materials, the metal oxides in powder form are mixed with a reducing agent such as calcium or magnesium in powder form or in granular form. The powder mixture is preferably not compressed. The powder mixture is heated to a temperature in the range of 1000 ° C to 1500 ° C and held under a hydrogen atmosphere. This results in the formation of metal hydrides which are selectively dehydrogenated under vacuum or under an inert gas atmosphere (e.g. argon).

The invention is defined in the claims.

The resulting product has a higher purity than that achieved with previously known techniques. This makes it possible to use the resulting metal powders in a variety of different applications within the powder metallurgy industry.

The present invention will now be described, by way of non-limiting example only, with reference to the accompanying drawings.
Figure 1 is an SEM micrograph of the product powder generated from TiO ₂ + 1.3XCa granules at 1100 ° C for 2 hours under an argon gas atmosphere.
Figure 2 shows the EDS spectrum of the resulting product powder from TiO ₂ + 1.3XCa granules at 1100 ° C for 2 hours under an argon gas atmosphere.
Figure 3 shows the XRD pattern of the resulting product material for reduction of TiO ₂ and 1.2XCa granules heat treated at 1100 ° C for 2 hours under argon gas protection. The XRD pattern showed that titanium was the first major phase of the material, but at the same time showed calcium titanium oxide as the second phase of the material. This means that the reduction reaction process has not been successfully processed under the above-mentioned conditions.
Figure 4 is a SEM micrograph of the resulting powder from TiO ₂ + 1.3X Ca granules at 1100 ° C for 2 hours under H ₂ , which is then converted to Ar gas.
Figure 5 shows the EDS spectrum of the resulting product powder from TiO ₂ + 1.3X Ca granules at 1100 ° C for 2 hours under H ₂ then converted to Ar gas.
Figure 6 shows the XRD pattern of the resulting product powder from TiO ₂ + 1.3xCa granules at 1100 ° C for 2 hours under H ₂ gas converted to argon gas. The XRD pattern shows the major components in the resulting product where the titanium metal has little or no contaminants.
FIG. 7 shows the results of a comparison of Cr ₂ O ₃ and 1.3X CaH ₂ for 2 hours at 1100 ° C under H ₂ gas during both heating and cooling periods SEM micrographs of Cr from the powder. The particles have a spheroidal shape.
8 is a graph showing the relationship between Cr ₂ O ₃ and 1.3X CaH ₂ for 2 hours at 1100 ° C under H ₂ gas during both heating and cooling periods The EDS spectrum of the resulting product powder from the powder is shown.
9 is a graph showing the relationship between Cr ₂ O ₃ and 1.3X CaH ₂ for 2 hours at 1100 ° C under H ₂ gas during both heating and cooling periods XRD < / RTI > of the resulting product powder of the chromium powder from the powder.
10 is an SEM micrograph of Nb metal powder from Nb ₂ O ₅ + 1.2 CaH ₂ - Ar heating during both heating and cooling periods.
Figure 11 shows the EDS spectrum of product powder Nb ₂ O ₅ + 1.2 CaH ₂ -Ar heating that occurred during both heating and cooling periods.
12 is an SEM micrograph of the tantalum powder prepared according to Example 12. Fig.

The present invention relates to a cost effective process for producing hydrides or alloys of metal powders and metal powders comprising the following steps or comprising the steps of:

The present invention provides a process for preparing a metal-containing powder, said process comprising:

a. Mixing one or more metal oxide powders in the form of granules or powder with Ca, Mg, calcium hydride, manganese hydride or a mixture thereof;

b. Maintaining the mixture under an atmosphere of H ₂ at a temperature of 1000 ° C to 1500 ° C for 1 to 10 hours; next

c. And recovering the powder containing the metal.

In one embodiment, the metal-containing powder is a metal hydride powder or metal alloy or intermetallic hydride. In this aspect, the invention provides a process as defined above, wherein the metal hydride powder is recovered.

The present invention provides a process for producing a metal hydride powder,

a. Mixing at least one metal oxide powder with Ca or Mg granules and / or a calcium hydride in granular or powder form to form a mixture;

b. Maintaining the mixture under a H ₂ atmosphere at a temperature of 1020 ° C to 1100 ° C for 2 to 4 hours; After that

c. And recovering the metal hydride powder.

In another embodiment, the metal-containing powder is a metal powder, a metal alloy, or an intermetallic powder. In this aspect, the invention provides a process as defined above, further comprising: between steps (b) and (c):

(d) converting the H ₂ atmosphere to an Ar atmosphere and maintaining the mixture under this atmosphere for a period of 20 minutes to 5 hours (preferably 1 hour or more, usually about 1 hour or less); After that

(e) cooling in an Ar atmosphere,

The metal powder is recovered in step (c).

In one aspect, step (a) comprises mixing at least one metal oxide powder with calcium hydride or magnesium hydride in the form of Ca or Mg granules and / or granules or powder to form a mixture.

The one or more metal oxides are preferably selected from the following oxides:

(I.e., Sc, Y, La, Ce, Pr, and the like), Al, Si, Ti, V, Vr, Mn, Ge, Zr, Nb, In, Sn, Sb, Hf, Ta, W, , Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb), Th and / or U;

More preferably, Al, Si, Ti, V, Cr, Mn, Ge, Zr, Nb, In, Sn, Sb, Hf, Ta, W, Pb, Bi, Th and / or U;

And more preferably Al, Si, Ti, Cr, Mn, Ge, Zr, Nb, In, Sn, Sb, Hf, Ta, W, Pb, Bi, Th and / or U;

More preferably, Ti, Cr, Nb, Ta and / or W; And

Most preferably Ti, Cr, Nb and / or Ta.

In one embodiment, the at least one metal oxide is selected from oxides of Sc, Ti, V, Cr, Mn, Y, Zr, Nb, Hf, Ta, rare earth metals, Th, U and / or Si. In other embodiments, the oxides that can be used as starting materials are oxides of Al, In, Sb, Sn, Ge, Bi, and / or Pb. The oxides that can be used as starting materials in other embodiments are oxides of Ti, Cr, Al, V, La, Nb and / or Ta.

The preferences for the metal (s) present in the metal oxide (s) are applied corresponding to the metal (s) present in the product.

The temperature range for holding the mixture under an H ₂ atmosphere is preferably 1000 ° C to 1500 ° C, more preferably 1020 ° C to 1400 ° C, more preferably 1020 ° C to 1300 ° C, and further preferably 1020 ° C to 1200 ° C , More preferably from 1020 占 폚 to 1100 占 폚.

The time for which the mixture is maintained under an H ₂ atmosphere is preferably 1 to 10 hours, more preferably 1 to 5 hours, more preferably 2 to 4 hours and most preferably about 3 hours.

More specifically, the present invention provides a process for producing a metal hydride powder,

a) mixing at least one metal oxide powder with Ca or Mg granules or a calcium hydride or magnesium hydride in powder and / or granular or powder form to form a mixture;

b) maintaining the mixture under an H ₂ atmosphere at a temperature of 1020 ° C to 1100 ° C for 2 to 4 hours; After that

c) recovering the metal hydride powder.

The present invention also provides a metal powder making process comprising the steps a) and b) above, followed by the following.

d) converting the H ₂ atmosphere to an Ar atmosphere and maintaining the mixture under this atmosphere for a period of at least 1 hour; After that

e) cooling in an Ar atmosphere; And

f) recovering the metal powder.

In this connection, step d) is carried out at a temperature of from 1000 캜 to 1500 캜, preferably from 1020 캜 to 1400 캜, more preferably from 1020 캜 to 1300 캜, more preferably from 1020 캜 to 1200 캜 and still more preferably from 1020 캜 RTI ID = 0.0 > 1100 C. < / RTI > Typically, the temperature maintained in step d) is substantially equal to the temperature used in step b).

The mixture is maintained under an Ar atmosphere for about 1 hour, but it can vary between 20 minutes and 5 hours, preferably between 40 minutes and 3 hours, preferably between 50 minutes and 2 hours, more preferably between 55 minutes and 80 minutes have.

Alternatively, the ratio of the number of oxygen atoms to the number of calcium atoms in the metal oxide (O: Ca) ranges from 1: 1.7 to 1.1 or 1: 1.5 to 1: 1.1 or 1: 1.5 to 1: 1.05 or 1: 1: 2, or 1: 1.2.

Optionally, the metal oxide powder is a TiO ₂ powder and the powder mixture is maintained at a temperature between 1020 ° C and 1100 ° C for about 3 hours under an H ₂ atmosphere in step b).

The present invention also includes a metal powder or metal hydride powder prepared according to the above methods.

In one aspect, the present invention provides a metal powder or metal hydride powder, wherein the metal is defined herein to be other than Ti. The present invention comprises a metal powder or metal hydride powder to be produced, wherein the metal is Ti, Cr, Nb or Ta. In a particularly preferred embodiment, the metal is Cr.

The present invention comprises a metal powder or metal hydride powder to be produced, wherein the metal is substantially free of oxygen.

The present invention includes a metal powder or metal hydride powder to be produced having an oxygen content of less than 0.35 wt%.

The term "metal oxide" refers to a metal oxide in the form of dissolved oxygen, oxide inclusions and / or oxide coatings in such quantities that make the metal particles unsuitable for use in manufacturing using PM technologies. It may also comprise metal particles containing positive oxygen.

The Ca or Mg granules are preferably in the range of 0.03 to 2 mm in size. Of the same size range Ca hydride (CaH ₂₎ and / or magnesium hydride granules may also be used.

As defined herein, the term "powder" is intended to describe a collection of particles having a size in the range of 50 nm to 1 mm.

The particle size distribution X50 (sometimes denoted as D50) is also known as the median diameter or the median value of the particle size variance, and is the value of the particle diameter at 50% of the cumulative dispersion. The particle size distribution of the products produced by the present process typically has an X50 of less than 40 [mu] m, less than 35 [mu] m, less than 25 [mu] m or less than 20 [mu] m. The particle size and size distribution can be determined, for example, by light scattering.

X50 dispersions are described in Powder Metallurgy, Powder Metallurgy for Metals, ISBN 0-87170-013-1, Volume 7, 9th Revised Edition, Metals Park, OHIO 44073, American Society for Metals Quot; Handbook "pages 216-218.

The amount of contaminants (e.g., oxygen or nitrogen) of the resulting product can be determined by combustion analysis and detection through IR absorption (to determine oxygen levels) or thermal conductivity (to determine nitrogen levels).

The starting materials also include one or more additional metal-containing reagents that can be, in addition to just one metal oxide, one or more metals or metal oxides (preferably metal oxides). In this case, the resulting product may be a metal alloy or an intermetallic compound. Preferably, it is a metal alloy. The term "metal powder" is thus intended to include pure metals, metal alloys and also intermetallic compounds. In this regard, elemental metal powders such as iron, aluminum, nickel, copper, etc. may be added to the reaction mix to provide a source of additional elements (e.g., to provide alloying elements). Oxides of these elements, for example Fe ₃ O ₄ , can also be used. The resulting product is metal alloy powder or intermetallic compound powder. In a preferred embodiment, the metal oxide powder is a TiO ₂ powder.

Similar considerations apply to embodiments of the present invention in which the product is a hydride, that is, the product of step b) is recovered (without subsequent possible steps of conversion to an Ar atmosphere and cooling under an Ar atmosphere and recovering the metal powder) . Thus, the starting materials also include one or more additional metal-containing reagents which can be, in addition to only one metal oxide, one or more metals or metal oxides (preferably metal oxides). In such a case, the resulting product may be a metal alloy hydride or an intermetallic hydride compound. In this regard, elemental metal powders such as iron, aluminum, nickel, copper, etc. may be added to the reaction mixture to provide a source of additional elements (e.g., to provide alloying elements). Oxides of these elements, for example Fe ₃ O ₄ , can also be used. The resulting product is a hydride (in powder form) of a metal alloy or intermetallic compound.

The one or more additional metal-containing reagents are preferably included in the reaction mixture in powder or granular form, most preferably in powder form.

When the product of the process of the present invention is a hydride, hydrogen may be part of a substantially ordered crystal structure, but alternatively hydrogen may be contained in the metal (s) in the form of a solid solution.

As a general rule, the percentages provided in connection with the content of components imparted in the alloy are preferably expressed in percentage by weight, and the percentages provided relative to the content of the imparted component of the intermetallic compound are preferably Are expressed in percentage by mol. Unless otherwise indicated, the percentages referred to herein follow these general rules.

The metal oxides may be present on the surface of the metal particles or components as, for example, the peripheral layer on the metal particles is exposed to oxidizing conditions.

The powder mixture of step b) is preferably maintained under a H ₂ atmosphere at a temperature between 1020 ° C and 1100 ° C, preferably for 3 hours.

It is desirable to perform a reduction under conditions that avoid initiation of a strong exothermic reaction. In this sense, the "strong" exothermic reaction is analyzed as an uncontrolled, thermal runaway reaction. Such uncontrolled exothermic reactions (eg, self-ignition combustion synthesis) are considered to cause less pure material.

These unwanted reactions can be avoided, for example, by using a specific ratio between oxygen and calcium, and optionally maintaining the reactants in a non-compressed form. In addition, the reduction reaction should ideally occur under a hydrogen atmosphere. If a compacted form of the reaction is used, it should ideally be in the form of thin plates, pellets, or granules.

The resulting powders may undergo a drying step to remove moisture.

The resulting metal powder typically has a particle size of less than 25 [mu] m. In addition, the metal powder is of high purity and has an oxygen content of less than 0.35% by weight.

Examples

The devices used to perform the experimental work are:

Any type of furnace suitable for operation under temperatures for the reduction reaction, i. E. Up to 1500 DEG C, may be used. The furnace also has to be fitted with means for supplying various types of gases, or applying vacuum to some cases. For the purposes herein, an open muffle open furnace was used to perform the thermal treatment processes to achieve the reduction reaction of the oxides used in the different working steps.

A crucible of rectangular cross-section with a flat base was used. The crucible is made of a high temperature resistant material, such as chrome nickel steel (253 MA), for example. The crucible was introduced into the furnace in each heat treatment process.

The heat treatment was carried out at different temperatures and times according to the examples below. The actual temperature of the furnace was measured using a thermocouple to compare the set temperature with the actual temperature. The difference between the actual temperature and the set temperature was less than 10 ° C.

Containers filled with water were used for cleaning. The intermediate product after the heat treatment was added to the water and cleaned. The containers were equipped with stirrers to stir the mixture of water and intermediate material. Acetic acid was added to the slurry by continuous stirring.

After cleaning, the resulting powder was dried to produce the resulting product.

The starting materials, metal hydrides and their alloy powders used to produce the different metals are as follows:

Table 1. Starting materials used in the following examples

The calcium hydride can be prepared from its elements by a direct combination of calcium and hydrogen at 300 to 400 < 0 > C. Calcium granules were obtained from the Mashinostroitelny Zavod division (Russia, 144001, Moscow region, Yellowtrol).

The amount of contaminants (e.g., oxygen or nitrogen) was determined by combustion analysis, followed by IR absorption (to determine oxygen levels) or by thermal conductivity (to determine nitrogen levels). The instrument used was LECO TC436DR.

Example 1:

Comparison of the preparation of titanium from TiO ₂ powder and calcium granules as starting materials

100 g of 325 mesh, 99% pure, TiO ₂ (Aldrich) in powder form was mixed with 130 g of 0.4-2 mm calcium granules (Mashinostroitel'nyi zavod, Russia). The powders and granules were thoroughly mixed and placed in the crucible as described above. The mixture was heated to 1100 < 0 > C for 2 hours in an open muffle furnace under argon gas. The resulting titanium powder particles had an X50 particle size of 35 mu m and formed into agglomerates. The oxygen content was 2.7%, the nitrogen content was 0.38%, and the hydrogen content was 0.26%. The XRD pattern shows that titanium is the first major phase of the material and also shows that calcium titanium oxide is the second phase of the material. This means that the reduction reaction process was not completely treated under the conditions mentioned above.

The calcium content was 2.9% as shown by ICP analysis.

Example 2:

Preparation of titanium from TiO ₂ powder (100 g) and calcium granules (130 g) as starting materials

This example was carried out by the above-mentioned heat treatment conditions except that heating was only carried out under hydrogen gas and also for 2 hours and thereafter converted to argon gas. The resulting titanium powder particles had an X50 particle size of 117.64 탆 and did not form agglomerates. The oxygen content was 0.30%, the nitrogen content was 0.08%, and the hydrogen content was 0.28%. The XRD pattern showed that titanium was obtained without impurities. This confirms that the heat treatment of the TiO ₂ and calcium granules was successful under the same heat treatment conditions, except that the dehydrogenation reaction was carried out under hydrogen gas protection and subsequently in an argon atmosphere.

The calcium content was 0.25% as shown by ICP analysis.

Example 3:

Preparation of titanium from (100 g) TiO ₂ and (145 g) CaH ₂ granules. TiO ₂ (Aldrich) in powder form was mixed with CaH ₂ granules (Hoeganaes AB) (less than 0.4 to 2 mm).

The mixture was heated to 1100 占 폚 for 2 hours under hydrogen gas in an open muffle furnace. After heating, the mixture was cooled under an argon atmosphere for 1 hour.

The resulting titanium powder particles had an X50 particle size of 20.06 mu m and did not form agglomerates. The oxygen content was 0.27%, the nitrogen content was 0.016%, and the hydrogen content was 0.17%. The XRD pattern showed that titanium was obtained without impurities.

The calcium content was 0.22% as shown by ICP analysis.

Example 4:

Preparation of titanium hydrides from TiO ₂ and CaH ₂ granules

100 g (Aldrich) of TiO ₂ in powder form was mixed with 145 g of calcium hydride granules (Hoeganaes AB) in the size of 0.4 to 2 mm. The mixture of powders and granules was heated to 1100 캜 for 2 hours under hydrogen gas in an open muffle furnace. After heating, the mixture was cooled under a hydrogen atmosphere for 1 hour.

The resulting titanium hydride powder particles had an X50 particle size of 6.35 mu m and did not form agglomerates. The oxygen content was 0.17%, the nitrogen content was 0.73%, and the hydrogen content was 3.63%. The XRD pattern showed that the titanium hydride was obtained without impurities.

The calcium content was 0.17% as shown by ICP analysis.

Example 5:

Preparation of Cr from Cr ₂ O ₃ and CaH ₂ Powders (100 g of Cr ₂ O ₃ (Aldrich) in powder form was mixed with 99.7 g of calcium hydride powder (Aldrich)).

The mixture was heated to 1100 占 폚 for 2 hours under hydrogen gas in an open muffle furnace. Both the heating and cooling periods were carried out under hydrogen gas protection.

The resulting chromium metal powder particles had an X50 particle size of 5.93 mu m and did not form agglomerates. The oxygen content was 0.08%, the nitrogen content was 0.003%, and the hydrogen content was 0.006%. The XRD pattern shows that chromium was obtained without impurities.

The calcium content was 0.004% as shown by ICP analysis.

Example 6:

Preparation of Titanium Hydride from TiO ₂ and CaH ₂ Powder (Metal Hydride)

TiO _{2 in} powder form (Aldrich) 100 g was mixed with 145 g of calcium hydride powder (Aldrich) in -325 mesh. The mixture was heated to 1100 占 폚 for 2 hours under a hydrogen gas in an open muffle furnace. Both the heating and cooling periods were maintained under hydrogen gas protection.

The resulting titanium hydride powder particles had an X50 particle size of 8.06 mu m and did not form agglomerates. The oxygen content was 0.12%, the nitrogen content was 0.72% and the hydrogen content was 3.42%. The XRD pattern shows that the titanium hydride was obtained without impurities.

The calcium content was 0.19% as shown by ICP analysis.

Example 7

Preparation of Ti19Al (alloy)

135 g of TiO _{2 in} powder form (Aldrich) were mixed with 19 g of Al powder (Aldrich) which had been mixed with 141.7 g of calcium granules (Mashinostroitel'nyi zavod, Russia)).

The mixture was heated to 1100 占 폚 for 2 hours under hydrogen gas, then argon gas, in an open muffle furnace.

The resulting Ti19Al powder particles had an X50 particle size of 16.4 mu m and did not form agglomerates. The oxygen content was 0.28%, the nitrogen content was 0.03%, and the hydrogen content was 0.27%. The XRD pattern shows that Ti19Al was obtained without impurities.

The calcium content was 0.03% as shown by ICP analysis.

Example 8

Manufacture of ferro-titanium hydride powders (intermetallic, solid solution of hydrogen)

103.5 g of TiO _{2 in} powder form (Aldrich) was mixed with CaH ₂ Was mixed with 218.1 g of powder (Aldrich) and 100 g of Fe ₃ O ₄ powder (Aldrich) mixed. The mixture was heated to 1100 占 폚 for 3 hours under a hydrogen gas in an open muffle furnace. Both the heating and cooling treatments were maintained under hydrogen gas protection.

The resulting ferrotitanium powder particles had a particle size with an X50 of 10.69 mu m and did not form agglomerates. The oxygen content was 0.13%, the nitrogen content was 0.06% and the hydrogen content was 2.07%. The XRD pattern shows that the ferro-titanium hydride powder was obtained without impurities.

The calcium content was 0.026% as shown by ICP analysis.

Example 9

Manufacture of Ti6Al4V (alloy)

TiO _{2 in} powder form (Aldrich) 150 g was mixed with 7.1 g of V ₂ O ₅ powder, and 6 g of Al (Aldrich) powders were mixed with 245 g of CaH ₂ granules 0.4 to 2 mm in size (syneresis ratio).

The mixture was converted to hydrogen gas in an open muffle furnace, followed by an argon gas atmosphere and heated to 1100 DEG C for 3 hours. The conversion of the gases was carried out in an open muffle furnace, without the need for transfer to another furnace for the dehydrogenation stage.

The resulting Ti6Al4V powder particles had an X50 particle size of 9.73 mu m and did not form agglomerates. The oxygen content was 0.24%, the nitrogen content was 0.05%, and the hydrogen content was 0.08%. The XRD pattern shows that Ti6Al4V was obtained without impurities.

The calcium content was 0.017% as shown by ICP analysis.

Example 10

Preparation of LaNi ₅ powder (intermetallic)

La ₂ O ₃ in the form of a powder (Aldrich) 55.5 g was mixed with (a time Nass ABS) CaH2 granules of 0.4-2mm size Ni powder 100 g was mixed with 43 g.

The mixture was hydrogen gas protected in an open muffle furnace, then converted to an argon gas atmosphere and heated to 1080 DEG C for 6 hours. Conversion gases were run in the same furnace without the need for transfer to another furnace for the dehydrogenation step.

The resulting LaNi ₅ powder particles had an X50 particle size of 9.57 탆 and did not form agglomerates. The oxygen content was 0.17%, the nitrogen content was 0.08%, and the hydrogen content was 0.04%. The XRD pattern shows that LaNi ₅ was obtained without impurities.

The calcium content was 0.06% as shown by ICP analysis.

Example 11

The niobium metal powder is subjected to heat treatment at 1050 ° C for 2 hours under transition gases after hydrogen for the cooling period to be carried out under argon gas protection of starting materials Nb ₂ O ₅ and CaH ₂ granules (as a stoichiometric ratio) Respectively.

Example 12

The tantalum metal powder from the Ta ₂ O ₅ and CaH ₂ granules (as an equivalent ratio of 1.2) was heat treated at 1050 ° C for 2 hours. After the hydrogen gas protection for dehydrogenation, it was heated under the argon gas environment (in the same furnace without changing the furnace). SEM micrographs showed that the material consisted of agglomerates of different sizes. These agglomerates consisted mainly of very fine size particles except for slightly larger sizes of large agglomerates. Generally, the agglomerates were very fine particle sizes as shown in Fig.

Claims (12)

As a process for producing a metal-containing powder,
The method comprises:
a. Mixing at least one metal oxide with Ca, Mg, calcium hydride, magnesium hydride or a mixture thereof in granular or powder form to form a mixture;
b. Maintaining the mixture at a temperature between 1000 ° C and 1500 ° C for 1 to 10 hours under an atmosphere of H ₂ ,
c. And recovering the metal-containing powder.
A method for producing a metal-containing powder.
The method according to claim 1,
A method for producing a metal hydride powder,
The method comprises:
a. Mixing at least one metal oxide with Ca, Mg, calcium hydride, magnesium hydride or a mixture thereof in granular or powder form to form a mixture;
b. Maintaining the mixture at a temperature between 1020 ° C and 1100 ° C for 2 to 4 hours under an atmosphere of H ₂ ,
c. And recovering the metal hydride powder.
A method for producing a metal-containing powder.
The method according to claim 1,
A method for producing a metal powder,
Comprising steps a) and b) of claim < RTI ID = 0.0 > 1,
d. Converting the H ₂ atmosphere to an Ar atmosphere and maintaining the mixture under the atmosphere at a temperature between 1000 ° C. and 1500 ° C. for 20 minutes to 5 hours,
e. Cooling in an Ar atmosphere, and
f. And recovering the metal powder.
A method for producing a metal-containing powder.
4. The method according to any one of claims 1 to 3,
The ratio (O: Ca) between the number of oxygen atoms of the metal oxide and the number of calcium atoms is 1: 1.7-1.1 or 1: 1.5-1: 1.1 or 1: 1.5-1: 1.05 or 1: 1.4-1: Or 1: 1.2,
A method for producing a metal-containing powder.
5. The method according to any one of claims 1 to 4,
The metal may be selected from the group consisting of Al, Si, Ti, V, Cr, Mn, Ge, Zr, Nb, In, Sn, Sb, Hf, Ta, W, Pb, Bi, rare earth metals , La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm and Yb), Th and /
A method for producing a metal-containing powder.
6. The method of claim 5,
Wherein the metal is Ti, Cr, Nb, W or Ta,
A method for producing a metal-containing powder.
5. A method for producing a metal powder according to any one of claims 1 to 4,
Wherein the metal powder is a TiO ₂ powder and the powder mixture is maintained in step b) under an H ₂ atmosphere at a temperature between 1020 ° C. and 1100 ° C. for 3 hours,
A method for producing a metal-containing powder.
8. The method according to any one of claims 1 to 7,
Wherein the step comprises including one or more additional reagents in the mixture, wherein the one or more additional reagents are one or more metals or metal oxides,
A method for producing a metal-containing powder.
A metal powder or metal hydride powder prepared according to the process of any one of claims 1 to 8.
10. The method of claim 9,
The metal may be Ti, Cr, Nb, W or Ta,
Metal powder or metal hydride powder.
11. The method according to claim 9 or 10,
The metal is substantially free of oxygen,
Metal powder or metal hydride powder.
The method according to any one of claims 9, 10 or 11,
Having an oxygen content of less than 0.35 wt%
Metal powder or metal hydride powder.

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