Oxygen-depleted alsc alloy powder and method for producing the same

Abstract

The present invention relates to A1Sc alloy powders characterized by high purity and low oxygen content, as well as to a method for their production and their use in the electronics industry.

Description

[0001] This invention relates to AlSc alloy powder characterized by high purity and low oxygen content, as well as its production method and its use in the electronics industry and electronic components.

[0002] Scandium, a rare earth metal, is experiencing steady growth in demand, particularly driven by its continued development in mobile communication technologies, electric vehicles, and advanced aluminum alloys with specific mechanical properties. As an alloying component, scandium is used alongside aluminum, for example, as a dielectric AlScN layer in BAW (bulk acoustic wave) filters, in electronic components in the electronics industry, and for wireless transmissions such as WLAN and mobile communications. For this purpose, an AlSc sputtering target is first prepared from AlSc alloy powder or elemental form, and then used to produce the dielectric layer.

[0003] Applications using AlSc alloy powders require high purity, which is challenging in the processing of scandium due to its tendency to form a natural oxide layer in air. Furthermore, scandium is difficult to produce in metallic or alloy form due to its highly reactive properties and strong affinity for oxygen. Therefore, there is a need for high-purity AlSc alloy powders and their production methods.

[0004] Typically, AlSc alloys are obtained through the interaction of these two metals, in which scandium can be pre-formed by the reaction of ScF3 with calcium. However, a drawback of this method is that after removing the CaF2 that is also formed as slag, scandium must be purified by sublimation at high temperatures, but the product usually still contains a large number of impurities, and due to the necessary high temperature, scandium is also contaminated by the crucible material.

[0005] Furthermore, existing technologies disclose several production methods in which scandium chloride reacts with aluminum according to the following reaction equation to form Al3Sc:

[0006] ScCl3 + 4Al → Al3Sc + AlCl3

[0007] Besides the high air and hydrolysis sensitivity of ScCl3, the production method also has the disadvantage of forming numerous byproducts due to the decomposition of raw materials, such as scandium oxide (Sc2O3) or scandium oxychloride (ScOCl), in addition to the target compound Al3Sc, as described by WWWendlandt in "The thermal decomposition of Yttrium, Scandium, and some rare-earth chloride hydrates" published in J. Inorg. Nucl. Chem., 1957, Vol. 5, pp. 118-122. Thus, the decomposition of ScCl3*6H2O leads to the formation of ScOCl and Sc2O3. To overcome this disadvantage, many methods involving the production of anhydrous ScCl3 as pure as possible are known.

[0008] WO 97 / 07057 describes a method for producing substantially pure and anhydrous rare earth metal halides by dehydration of their hydrated salts, wherein the hydrated rare earth metal halides are introduced into a fluidized bed system comprising a reactor or multiple coupled reactors, and a gaseous desiccant is added at elevated temperatures to obtain rare earth metal halides with a specific maximum water content and free from oxide impurities, but no description is given regarding chlorine oxide contamination.

[0009] EP 0 395 472 relates to dehydrated rare earth metal halides characterized by a water content of 0.01 to 1.5% by weight and a halide content of less than 3% by weight. Dehydration is achieved by passing a gas stream containing at least one dehydrated halogenated compound through a bed of the compound to be dehydrated at a temperature of 150 to 350°C. Hydrogen halides, halogens, ammonium halides, carbon tetrachloride, S₂Cl₂, SOCl₂, COCl₂, and mixtures thereof are mentioned as dehydrated halogenated compounds. However, this document does not indicate that the method is also applicable to the production of scandium.

[0010] US 2011 / 0014107 also discloses a method for producing anhydrous rare earth metal halides, wherein a slurry is formed from rare earth metal halide hydrates and an organic solvent, the slurry is heated under reflux, and water is finally distilled from the slurry.

[0011] CN 110540227 describes a method for producing high-quality anhydrous rare earth metal chlorides and bromides, wherein the hydrate of the rare earth metal halide, REX3*xH2O, is first pre-dried to obtain REX3. The pre-dried product is treated in a vacuum under water- and oxygen-free conditions and gradually heated to 1500°C to separate REX3 from the oxidation byproducts that also form during sublimation. A purity of 99.99% has been reported for the rare earth metal halides obtained in this manner. However, this method suffers from low yields, particularly for the production of ScCl3, because many oxidation byproducts, such as scandium oxide (Sc2O3) or scandium oxychloride (ScOCl), are formed during the pre-drying process.

[0012] Although the production methods for the high-purity feedstock compounds used to produce AlSc alloys are known in the prior art, it remains unknown how to convert these into the desired AlSc alloys on an industrial scale while maintaining high purity.

[0013] In this regard, WO 2014 / 138813 discloses a method for producing aluminum-scandium alloys from aluminum and scandium chloride, wherein scandium chloride is mixed with aluminum and then heated to a temperature of 600 to 900 °C, wherein the formed AlCl3 is removed by sublimation. The XRD pattern of the product (Figure 8) shows the formation of scandium metal and slight contamination by Sc2O3, except for the target compound Al3Sc; although this is not explicitly stated, it can be seen from the unmarked reflections at 31.5 2θ° (Cu) and 33 2θ° (Cu).

[0014] The common feature of existing methods is that they typically yield Al3Sc with relatively high oxygen and / or halide (chlorine and / or fluorine) content, which greatly limits the possibilities for the use of these powders.

[0015] Therefore, there remains a need for high-purity aluminum-scandium alloys (AlSc alloys) suitable for the electronics industry and mobile communication technologies, as well as methods for their production. In view of this, the object of the present invention is to provide a corresponding AlSc alloy suitable for the aforementioned applications.

[0016] It has been surprisingly discovered that this can be achieved through AlSc alloy powders characterized by low oxygen and other impurity content, particularly low chloride and / or fluoride content.

[0017] The first subject of this invention is therefore an alloy powder having an Al composition determined by means of X-ray fluorescence analysis (XRF). x Sc y , wherein 0.1≤y≤0.9 and x=1-y, and having a purity of 99% by weight or higher based on metallic impurities, wherein the alloy powder has an oxygen content of less than 0.7% by weight based on the total weight of the powder, as determined by means of a carrier gas thermal extraction method.

[0018] In one particular embodiment, the alloy powder of the present invention has an Al composition determined by X-ray fluorescence analysis (XRF). x Sc y Where 0.2 ≤ y ≤ 0.8, preferably 0.24 ≤ y ≤ 0.7, and in each case x = 1 - y. Furthermore, the alloy powder may also contain Al with different compositions. x Sc y The alloy powder of the present invention is particularly preferably a mixture of Al3Sc (x = 0.75; y = 0.25) or Al2Sc (x = 2 / 3; y = 1 / 3) and these compounds.

[0019] In another preferred embodiment, the alloy powder of the present invention has a purity of 99.5% or higher, particularly preferably 99.9% by weight or higher, based on metal impurities in each case.

[0020] The powder of the present invention is particularly characterized by its low oxygen content. Therefore, a preferred embodiment is one in which the alloy powder has an oxygen content of less than 0.5% by weight, preferably less than 0.1% by weight, and particularly preferably less than 0.05% by weight, in each case based on the total weight of the powder. The oxygen content of this powder can be determined here by means of a carrier gas thermal extraction method.

[0021] It has been surprisingly discovered that the powder of the present invention is particularly suitable for applications requiring high purity. In addition to its low oxygen content, it has also been surprisingly discovered that the powder has a low chloride content, which is crucial for the electronics industry. Therefore, a preferred embodiment is one in which the alloy powder of the present invention has a chloride content of less than 1000 ppm, preferably less than 400 ppm, particularly preferably less than 200 ppm, and especially less than 50 ppm, as determined by ion chromatography.

[0022] For the purposes of this invention, the data for "ppm" in each case refers to parts per million based on the total weight of the powder.

[0023] In practice, it has been found that, in particular, metallic scandium and oxide and halogen-containing impurities cause difficulties in further processing; these impurities are typically detectable by X-ray diffraction. These impurities are not only scandium oxides such as Sc₂O₃ and ScOCl, but also oxide impurities introduced via the reactants used. Therefore, an embodiment of the invention is preferred, wherein the X-ray diffraction pattern of the alloy powder of the invention shows no reflections from compounds selected from Sc₂O₃, ScOCl, ScCl₃, Sc, X₃ScF₆, XScF₄, ScF₃ and other oxide impurities and fluorinated foreign phases, where X is a potassium or sodium ion. Other oxide impurities can be, for example, MgO, Al₂O₃, CaO and / or MgAl₂O₄.

[0024] Furthermore, a preferred embodiment is one in which the alloy powder of the present invention has a magnesium content of less than 5000 ppm, preferably less than 2500 ppm, particularly preferably less than 500 ppm, and especially less than 100 ppm, as determined by ICP-OES. In another preferred embodiment, the alloy powder of the present invention has a calcium content of less than 5000 ppm, preferably less than 2500 ppm, particularly preferably less than 500 ppm, and especially less than 100 ppm, as determined by ICP-OES. In yet another preferred embodiment, the alloy powder of the present invention has a sodium content of less than 5000 ppm, preferably less than 2500 ppm, particularly preferably less than 500 ppm, and especially less than 100 ppm, as determined by ICP-OES. For the purposes of this invention, the terms "magnesium content," "sodium content," and "calcium content" encompass both elemental compounds and ions.

[0025] In another preferred embodiment, the alloy powder of the present invention has a fluorine content of less than 1000 ppm, preferably less than 400 ppm, particularly preferably less than 200 ppm, and especially less than 50 ppm, as determined by ion chromatography.

[0026] The alloy powder of the present invention is particularly suitable for further processing in the electronics industry, for example as a precursor for the production of sputtering targets and dielectric layers made therefrom, where not only high purity but also appropriate particle size is important. Therefore, a preferred embodiment is one in which the alloy powder has a particle size D90 of less than 2 mm, preferably 100 μm to 1 mm, and particularly preferably 150 μm to 500 μm, as determined according to ASTM B822-10. The D90 value of the particle size distribution refers to the particle size of 90% by volume of the particles having a particle size equal to or less than the value shown.

[0027] Another subject of this patent application is a method for producing the alloy powder of the present invention, wherein a scandium source is reacted together with aluminum metal or an aluminum salt in the presence of a reducing agent to produce Al. x Scy Wherein 0.1≤y≤0.9, preferably 0.2≤y≤0.8, particularly preferably 0.24≤y≤0.7, and in each case x=1-y. According to the invention, the reducing agent is different from aluminum or aluminum salts and does not contain any aluminum. The aluminum salt is preferably selected from X3AlF6, XAlF4, AlF3, and AlCl3, where X is a potassium or sodium ion. It has been surprisingly found that the method of the invention can avoid or significantly reduce the formation of undesirable oxide impurities, and in this way, AlSc alloy powder with high purity and low oxygen content can be obtained.

[0028] Although conventional production methods typically rely on expensively produced ScCl3 or Sc metal as raw materials, the method of the present invention is characterized by the fact that the reaction can also be initiated from scandium oxides and chlorides, and from ScCl3 contaminated with ScOCl and / or Sc2O3, thus eliminating the need for complex dehydration or purification of reactants as described in the prior art. Therefore, an embodiment of the method of the present invention is preferred, wherein the scandium source is selected from Sc2O3, ScOCl, ScCl3, ScCl3*6H2O, ScF3, X3ScF6, XScF4, and mixtures of these compounds, wherein X is a potassium or sodium ion.

[0029] In particular, alkali metals and alkaline earth metals have been found to be suitable reducing agents in the method of the present invention. In a preferred embodiment, the reducing agent is therefore selected from lithium, sodium, potassium, magnesium, and calcium, wherein, according to the present invention, sodium and potassium are particularly used for the reaction of scandium fluoride, and magnesium and calcium are used for the reaction of scandium chloride. The use of the reducing agent shown has the advantage that the oxidation products of the reducing agent formed in the reduction, such as MgO, MgCl2, and NaF, can be easily removed by washing. Therefore, an embodiment of the method is preferred, which further includes the step of washing the resulting alloy powder. For example, distilled water and / or dilute inorganic acids, such as H2SO4 and HCl, can be used to wash the powder.

[0030] It has been surprisingly found that the introduction of impurities can be further reduced when the reducing agent is introduced in vapor form. Therefore, an embodiment in which the reducing agent is used in vapor form is preferred.

[0031] It has been found particularly effective to react ScCl3, ScOCl, and / or Sc2O3, or mixtures of these compounds, as scandium sources with aluminum metal and magnesium as a reducing agent. Surprisingly, it has been found that the purity of the resulting AlSc alloy powder can be further improved when the aluminum metal and magnesium are pre-alloyed before the reaction. Therefore, a preferred embodiment of the method of the invention is one in which aluminum metal and magnesium are reacted in the form of an Al / Mg alloy with ScCl3, ScOCl, and / or Sc2O3, or mixtures of these compounds, to produce AlxScy, wherein 0.1 ≤ y ≤ 0.9, preferably 0.2 ≤ y ≤ 0.8, particularly preferably 0.24 ≤ y ≤ 0.7, and in each case x = 1 - y.

[0032] It has been found particularly advantageous to use aluminum metal and / or Al / Mg alloys in coarse powder form, as this reduces the surface oxygen introduced by these reactants and thereby further reduces the oxygen content of the resulting alloy powder. Therefore, a preferred embodiment is one in which the aluminum metal and / or Al / Mg alloy is present in powder form, wherein the powder preferably has an average particle size D50 greater than 40 μm, preferably 100 μm to 600 μm, and a D90 greater than 300 μm, preferably 500 μm to 2 mm, as determined by ASTM B822-10. The D90 value of the particle size distribution refers to 90% by volume of particles having a particle size equal to or less than the value shown; correspondingly, the D50 value refers to 50% by volume of particles having a particle size equal to or less than the value shown.

[0033] A preferred embodiment of the method of the present invention is characterized by the fact that it can be carried out at temperatures significantly lower than those conventional in the prior art, thus avoiding inclusions of oxidized reducing agents, such as MgCl2 or MgO, in the alloy powder and thereby further improving its purity. This is particularly suitable for the use of Al / Mg alloys, as a decrease in melting point is observed when alloying Al and Mg. Therefore, a preferred embodiment of the method of the present invention is characterized by the reaction being carried out at a temperature of 400 to 1050°C, preferably 400 to 850°C, and particularly preferably 400 to 600°C. Here, the reaction time is preferably 0.5 to 30 hours, preferably 1 to 24 hours.

[0034] Particularly when aluminum and magnesium are used with ScCl3 as a scandium source, it has been found advantageous that the reactants are vaporized separately and then combined as vapors in the reaction space. In this way, oxidized impurities in the feedstock can be separated before the reaction. Therefore, a preferred embodiment is one in which ScCl3, aluminum, and magnesium are vaporized separately, then combined as gaseous gases in the reaction space, and react to produce Al with the following composition. x Sc yThe alloy powder, wherein 0.1≤y≤0.9, preferably 0.2≤y≤0.8, particularly preferably 0.24≤y≤0.7, and in each case x=1-y.

[0035] It has been surprisingly discovered in this invention that the AlSc alloy powder of this invention can also be obtained from scandium fluoride salts. Therefore, another embodiment of the method of this invention is preferred, wherein the scandium fluoride salt is reacted with aluminum metal or an aluminum salt in the presence of sodium or potassium to produce an Al alloy having a composition of... x Sc y The alloy powder contains 0.1 ≤ y ≤ 0.9, preferably 0.2 ≤ y ≤ 0.8, particularly preferably 0.24 ≤ y ≤ 0.7, and in each case x = 1 - y. The scandium fluoride salt is preferably selected from ScF3, XScF4, X3ScF6, and any combination thereof, wherein X is potassium or sodium and mixtures thereof. The aluminum salt is preferably selected from AlF3, X3AlF6, and XAlF4, wherein X is potassium or sodium ion.

[0036] Reduction can be carried out using either a mixed reducing agent or a gaseous reducing agent. Alternatively, reduction can be carried out within the melt. The advantage of these alternatives according to the invention is that, unlike chlorides, scandium fluorides are stable in air and have low hygroscopicity, and can be obtained by precipitation from aqueous solutions. Therefore, they can be handled in air, which significantly facilitates their use in large-scale industrial processes.

[0037] The method of the present invention can produce particularly pure AlSc alloy powder characterized by low oxygen content. Another subject of the invention is therefore an alloy powder obtainable by the method of the invention, having an Al composition determined by X-ray fluorescence analysis (XRF). x Sc y Wherein 0.1 ≤ y ≤ 0.9, preferably 0.2 ≤ y ≤ 0.8, particularly preferably 0.24 ≤ y ≤ 0.7, and in each case x = 1 - y. The powder obtained in this manner preferably has an oxygen content of less than 0.7% by weight, preferably less than 0.5% by weight, particularly preferably less than 0.1% by weight, and especially less than 0.05% by weight, in each case based on the total weight of the powder and determined by means of a carrier gas thermal extraction method. The powder obtained in this manner particularly preferably has the above-described properties.

[0038] The alloy powder of the present invention is characterized by high purity and low oxygen content, making it particularly suitable for the electronics industry. Another subject of the invention is therefore to provide the use of the alloy powder of the present invention in the electronics industry or in electronic components, particularly for the production of sputtering targets and BAW filters.

[0039] The invention is explained in more detail by way of the following examples, but these should in no way be construed as limiting the inventive concept. Example:

[0040] 1. Production of the scandium sources ScCl3 and ScOCl (precursors P1 to P5) used

[0041] ScCl3 is produced in a manner similar to the prior art summarized in Table 1. Here, ScCl3*6H2O (purity Sc2O3 / TREO 99.9%), available from Shinwa Bussan Kaisha, Ltd., is used as a raw material in each case.

[0042] P1: Under P1 conditions, the reaction was carried out for 2 hours in an argon stream at 720°C without the addition of NH4Cl.

[0043] P2: P2 is based on Example 2 of EP 0 395 472 A1, but instead of NdCl3*6H2O described there, the corresponding Sc compound ScCl3*6H2O is used.

[0044] P3: P3 is based on Example 5 of CN110540117A, but instead of the LaCl3*7H2O / CeCl3*7H2O mixture described there, the corresponding hydrate ScCl3*6H2O is used.

[0045] P4: As P4, phase-pure ScOCl was prepared by heat treatment in a quartz glass tube with ScCl3*6H2O in an HCl gas stream at 900°C for 2 hours without the addition of NH4Cl.

[0046] P5: As P5, Sc2O3 (purity Sc2O3 / TREO 99.9%) is used, which is available from Shinwa Bussan Kaisha, Ltd.

[0047] The phase composition, oxygen content, and residual H2O content of each product as determined by X-ray diffraction (XRD) are also shown in Table 1.

[0048] 2. Comparative experiments C1 to C7

[0049] For comparative experiments C1 to C6, scandium-containing precursors P1 to P5, as shown in Table 2, were mixed with aluminum or magnesium powder and introduced into ceramic crucibles. The average particle size D50 of the aluminum powder used was 520 μm, and the average particle size D50 of the magnesium powder used was 350 μm. A thermal reaction was then carried out in an argon atmosphere, as shown in Table 2. The respective reaction products were then washed with dilute sulfuric acid, dried in a convection drying oven for at least 10 hours, and subsequently subjected to chemical analysis and X-ray diffraction examination. The results are also shown in Table 2.

[0050] For comparative experiment C7, Example 2 of WO 2014 / 138813A1 was repeated using precursor P3 (ScCl3) and aluminum powder with an average particle size D50 of 14 μm. After reaction under similar conditions as those disclosed therein, a powder with the following properties was obtained:

[0051] X-ray diffraction (XRD): Al3Sc

[0052] Chemical analysis: Oxygen 0.81 wt%, C 115000 ppm, F < 50 ppm, Mg < 10 ppm, Na < 10 ppm, Ca < 10 ppm

[0053] X-ray fluorescence analysis (XRF): Al:Sc ratio = 0.77:0.23

[0054] Particle size D50: 25μm

[0055] For all experiments, the total amount of all metallic impurities (including Mg, Ca, and Na) was determined to be <500 ppm.

[0056] 3. The experiment according to the present invention

[0057] a)E1 to E8

[0058] For experiments E1 to E8, scandium-containing precursors P1 to P5, as shown in Table 3, were mixed with powdered Al and Mg or Al / Mg alloys (69 wt% Al, 31 wt% Mg) and introduced into ceramic crucibles, similar to the methods used in comparative experiments C1 to C7. The average particle size D50 of the aluminum powder used was 520 μm, the average particle size D50 of the magnesium powder was 350 μm, and the average particle size D50 of the Al / Mg alloy was 380 μm. The thermal reaction was carried out in a steel distillation vessel with argon gas passing through throughout the reaction time, as shown in Table 3. The respective reaction products were then washed with dilute sulfuric acid, dried in a convection drying oven for at least 10 hours, and subsequently subjected to chemical analysis and X-ray diffraction examination. The results are also shown in Table 3. In all experiments, the sodium and calcium contents were <10 ppm in each case. In all experiments, the total amount of all metallic impurities (including Mg, Ca, and Na) was determined to be <400 ppm.

[0059] b) Experiments E9 to E34

[0060] Scandium- and aluminum-containing precursors were mixed and distributed on finely perforated niobium sheets in ratios similar to those shown in Tables 3 and 4. This mixture was placed in a steel reduction vessel filled with the amount of sodium required for the reaction plus a stoichiometric 50% excess. The niobium sheets were placed above the sodium but not in direct contact with it. The reaction took place in a steel distillation vessel through which argon gas passed throughout the reaction time. The sodium was vaporized, thus reducing the precursors to elemental Sc and Al, which reacted in situ to produce the target alloy.

[0061] After the reaction, the distillation vessel was carefully passivated with air, and then the steel reduction vessel was removed. Sodium fluoride formed during the reaction was washed from the reaction product with water, and then the product was dried at low temperature. For all experiments, the calcium content was <10 ppm and the sodium content was <50 ppm. For all experiments, the total amount of all metallic impurities (including Mg, Ca, and Na) was determined to be <400 ppm.

[0062] c) Experiments E35 to E42

[0063] Scandium- and aluminum-containing precursors (see Table 4) were mixed and introduced into a niobium vessel along with the required amount of sodium for the reaction, plus a stoichiometric 50% excess. The reaction took place in a steel distillation vessel through which argon gas passed throughout the reaction time. The precursors were reduced by sodium to elemental Sc and Al, which reacted in situ to produce the target alloy.

[0064] After the reaction, the distillation vessel was carefully passivated with air, and then the steel reduction vessel was removed. Excess sodium was dissolved by reaction with ethanol, and the remaining solid was washed with water. Sodium fluoride and / or sodium chloride were washed off from the reaction product, which was then dried at low temperature. For all experiments, the calcium content was <10 ppm and the sodium content was <50 ppm. For all experiments, the total amount of all metallic impurities (including Mg, Ca, and Na) was determined to be <400 ppm.

[0065] The oxygen content of the powder was determined by carrier gas thermal extraction (Leco TCH600), and particle size D50 and D90 were determined by laser diffraction (ASTM B822-10, MasterSizer S, dispersed in water and sonicated for 11.5 min in Daxad). Trace analysis of metallic impurities was performed using ICP-OES (Inductively Coupled Plasma Optical Emission Spectroscopy) with a PQ 9000 (Analytik Jena) or Ultima 2 (Horiba). The composition of the crystalline phase was determined by X-ray diffraction (XRD) on powdered samples using an instrument from Malvern-PANalytical (X′Pert-MPD Pro, with a semiconductor detector, a 40 kV / 40 mA CuLFF X-ray tube, and a Ni filter). The determination of halides F and Cl was based on ion chromatography (ICS 2100). The Axios and PW2400 instruments from Malvern-PANalytical were used for X-ray fluorescence analysis (XRF-X-ray fluorescence spectroscopy) of Al and Sc.

[0066] The various content data for chemical elements shown as % are all weight % and are based on the total weight of the powder in each case. Purity based on metal impurities in each case, expressed as weight %, is understood to be the result of subtracting all metal impurities determined as weight % from a 100% ideal value. The Al:Sc ratio was calculated from the Al and Sc contents determined by XRF.

[0067] The abbreviation TREO represents the total oxides of rare earth elements.

[0068] Table 1 - Production of ScCl3 precursors

[0069]

[0070] Table 2 Comparative examples used in the production of AlSc alloy powder

[0071]

[0072] Table 3: Embodiments of the present invention for producing AlSc alloy powder from ScCl3 precursors.

[0073]

[0074] Table 4: Embodiments of the present invention for producing AlSc alloy powder from Sc fluorides.

[0075]

[0076]

[0077] As can be seen from the data in Tables 3 and 4, the alloy powder of the present invention is characterized not only by its low oxygen content, but also by its low chlorine and fluorine content, which has not been achieved using methods known in the prior art. Furthermore, the experiments presented show that the method of the present invention can also produce high-purity AlSc alloy powder from scandium oxides, fluorides, and chlorides, thus eliminating the need for complex post-processing of the reactants.

[0078] Figure 1 The X-ray diffraction pattern of ScCl3 precursor P2 is shown.

[0079] Figure 2 The X-ray diffraction pattern of ScCl3 precursor P3 is shown.

[0080] Figure 3 The X-ray diffraction pattern of the AlSc alloy powder of Comparative Example C5 is shown.

[0081] Figure 4 The X-ray diffraction pattern of AlSc alloy powder according to Embodiment E7 of the present invention is shown.

[0082] Figure 5The X-ray diffraction pattern of AlSc alloy powder according to Embodiment E13 of the present invention is shown.

[0083] The X-ray diffraction patterns of the two AlSc alloy powders according to the invention depicted represent all experiments E1 to E42 described according to the invention. A comparison of the provided patterns shows that the patterns of the powders according to the invention exhibit no reflection other than that of the desired AlSc target compound.

Claims

1. Alloy powder, which has the composition Al x Sc y Where 0.1 ≤ y ≤ 0.9 and x = 1 – y, and having a purity of 99% by weight or higher based on metallic impurities, wherein the alloy powder has an oxygen content of less than 0.7% by weight based on the total weight of the powder, as determined by carrier gas thermal extraction, characterized in that… The X-ray diffraction pattern of the powder does not show Sc reflection.

2. The alloy powder according to claim 1, characterized in that... The alloy powder has a chlorine content of less than 1000 ppm, as determined by ion chromatography.

3. The alloy powder according to claim 1 or 2, characterized in that... The X-ray diffraction pattern of the powder shows no reflections from compounds selected from Sc2O3, ScOCl, ScCl3, Al2O3, X3ScF6, XScF4, ScF3 and other oxidized and fluorinated foreign phases, where X is a sodium or potassium ion.

4. The alloy powder according to claim 1 or 2, characterized in that... The alloy powder has a magnesium content of less than 5000 ppm, as determined by ICP-OES.

5. The alloy powder according to claim 1 or 2, characterized in that... The alloy powder has a particle size distribution D90 of less than 2 mm as determined according to ASTM B822-10.

6. The alloy powder according to claim 1 or 2, characterized in that... The alloy powder has a fluoride content of less than 1000 ppm, as determined by ion chromatography.

7. A method for producing alloy powder according to any one of claims 1 to 6, characterized in that... The scandium source is reacted with aluminum metal or aluminum salt in the presence of a reducing agent to produce Al. x Sc y Where 0.1 ≤ y ≤ 0.9, x = 1 – y, the reducing agent is selected from magnesium, calcium, lithium, sodium and potassium.

8. The method according to claim 7, characterized in that... The scandium source is selected from Sc2O3, ScOCl, ScCl3, ScCl3•6H2O, ScF3, X3ScF6 and XScF4 and mixtures of these compounds, wherein X is a potassium or sodium ion.

9. The method according to claim 7 or 8, characterized in that... Aluminum and magnesium are reacted with a scandium source in the form of an Al / Mg alloy to produce Al. x Sc y , where 0.1 ≤ y ≤ 0.9, x = 1 – y.

10. The method according to claim 9, characterized in that... Aluminum metal and / or Al / Mg alloys exist in powder form.

11. The method according to claim 7 or 8, characterized in that... Scandium fluoride salts are reacted with aluminum metal or aluminum salts in the presence of sodium or potassium to produce an Al-containing product. x Sc y The alloy powder, wherein 0.1 ≤ y ≤ 0.9, x = 1 – y.

12. The method according to claim 7 or 8, characterized in that... The reaction is carried out at a temperature of 400 to 1050 °C.

13. An alloy powder obtainable by the method according to any one of claims 7 to 12, having an Al composition. x Sc y , where 0.1 ≤ y ≤ 0.9, x = 1 – y.

14. Use of the alloy powder according to any one of claims 1 to 6 or the alloy powder according to claim 13 in electronic components in the electronics industry.

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