Preparation method and application of a high-purity powder material and an alloy strip

Abstract

The present invention relates to a method for preparing a high-purity powder material. First, an alloy strip with a solidification structure composed of a matrix phase and a dispersed particle phase is prepared by melt solidification. During the solidification process of the alloy strip, impurity elements are enriched in the matrix phase, so that the dispersed particle phase is purified. By removing the matrix phase in the alloy strip, a high-purity target powder material composed of the dispersed particle phase can be obtained. The preparation method of the present invention has the characteristics of simple process, easy operation and low cost, and can prepare high-purity powder materials including nanoscale, submicron scale, micron scale and millimeter scale, and has good application prospects in the fields of catalytic materials, powder metallurgy, composite materials, wave-absorbing materials, bactericidal materials, magnetic materials, metal injection molding, 3D printing, coatings, etc.

Description

Technical Field

[0001] The present invention relates to the technical field of metal materials, and particularly relates to a preparation method and application of a high-purity powder material and an alloy strip. Background Art

[0002] Powders with micro-nano particle sizes exhibit many peculiar properties different from traditional materials in aspects such as optics, electricity, magnetism, and catalysis due to special surface effects, quantum size effects, quantum tunneling effects, and Coulomb blockade effects, etc., and are thus widely applied in multiple fields such as optoelectronic devices, wave-absorbing materials, and high-efficiency catalysts.

[0003] Currently, the preparation methods of ultrafine powders are classified into solid-phase methods, liquid-phase methods, and gas-phase methods according to the state of substances. Solid-phase methods mainly include mechanical pulverization method, ultrasonic pulverization method, thermal decomposition method, explosion method, etc. Liquid-phase methods mainly include precipitation method, alcohol salt method, carbonyl method, spray thermal drying method, freeze drying method, electrolysis method, chemical coagulation method, etc. Gas-phase methods mainly include gas-phase reaction method, plasma method, high-temperature plasma method, evaporation method, chemical vapor deposition method, etc. Although there are many preparation methods for ultrafine powders, each method has certain limitations. For example, the disadvantages of liquid-phase methods are low yield, high cost, and complex process, etc. The disadvantage of mechanical methods is the difficulty in classification after powder preparation, and it is difficult to guarantee the purity, fineness, and morphology of the products. Rotary electrode method and atomization method are the main methods for preparing high-performance metal and alloy powders currently, but the production efficiency is low, the yield of ultrafine powders is not high, and the energy consumption is relatively large; Jet mill method and hydrogenation dehydrogenation method are suitable for large-scale industrial production, but they have strong selectivity for raw material metals and alloys.

[0004] In addition, the impurity content of powders, especially the oxygen content, has a great influence on their properties. Currently, the impurity content of metals or alloys is mainly controlled by controlling the purity of raw materials and the vacuum degree, with high costs. Therefore, it is of great significance to develop a new preparation method for high-purity powder materials. Summary of the Invention

[0005] Based on this, it is necessary to provide a preparation method and application of a high-purity powder material with simple process and easy operation for the above technical problems.

[0006] A preparation method of a high-purity powder material, characterized by comprising the following steps:

[0007] Step S1, select an initial alloy raw material, melt the initial alloy raw material according to the initial alloy composition ratio to obtain a uniform initial alloy melt containing impurity element T, where T includes at least one of O, H, N, P, S, F, Cl, I, Br, and the average composition of the initial alloy melt includes any one of the following combinations (1)-(4):

[0008] Combination (1): The average composition of the initial alloy melt is mainly A a (M x D y ) b T d , where A contains at least one of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu; M contains at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti; D contains at least one of Fe, Co, Ni, where x, y; a, b, d all represent the atomic percentage content of the corresponding constituent elements, and 24.9% ≤ a ≤ 99.4%, 0.5% ≤ b ≤ 75%, 0 < d ≤ 10%; preferably, 24.9% ≤ a ≤ 59.9%, 40% < b ≤ 75%, 0 < d ≤ 10%;

[0009] Furthermore, 10% ≤ x ≤ 55%, 45% ≤ y ≤ 90%;

[0010] Furthermore, the molar ratio x:y = 0.9 - 1.1;

[0011] Preferably, x = y = 50%, that is, the molar ratio x:y = 1:1;

[0012] Combination (2): The average composition of the initial alloy melt is mainly A a M b T d , where A contains at least one of Mg, Ca, Li, Na, K, Cu, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu; M contains at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti; where a, b, d represent the atomic percentage content of the corresponding constituent elements, and 24.9% ≤ a ≤ 99.4%, 0.5% ≤ b ≤ 75%, 0 < d ≤ 10%;

[0013] Preferably, when M contains at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti, A contains one of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu;

[0014] Preferably, when M contains at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti, A contains Cu;

[0015] Preferably, 24.9% ≤ a ≤ 54.9%, 45% < b ≤ 75%, 0 < d ≤ 10%;

[0016] Combination (3): The average composition of the initial alloy melt is mainly A a M b T d , where A contains at least one of Zn, Mg, Sn, Pb, Ga, In, Al, La, Ge, Cu, K, Na, Li; M contains at least one of B, Bi, Fe, Ni, Cu, Ag, Si, Ge, Cr, V, where a, b, d represent the atomic percentage contents of the corresponding constituent elements, and 24.9% ≤ a ≤ 59.9%, 40% < b ≤ 75%, 0 < d ≤ 10%;

[0017] Preferably, when M contains B, A contains at least one of Sn, Ge, Cu, Zn; when M contains Bi, A contains at least one of Sn, Ga, Al;

[0018] Preferably, when M contains at least one of Fe, Ni, Cu, Ag, A contains at least one of La, In, Na, K, Li, Pb, Mg; preferably, when M contains at least one of Fe, Ni, A contains at least one of La, In, Na, K, Li, Mg; when M contains at least one of Cu, Ag, A contains at least one of Pb, Na, K, Li;

[0019] Preferably, when M contains at least one of Si, Ge, A contains at least one of Zn, Sn, Pb, Ga, In, Al;

[0020] Preferably, when M contains at least one of Cr, V, A contains Zn;

[0021] Combination (4): When the average composition of the initial alloy melt is mainly A a M b Al c T d , A contains at least one of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu; M contains at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti; Al is aluminum; where a, b, c, d respectively represent the atomic percentage contents of the corresponding constituent elements, and 29.8% ≤ a ≤ 64.8%, 35% < b ≤ 70%, 0.1% ≤ c ≤ 25%, 0 < d ≤ 10%;

[0022] Furthermore, the average composition of the initial alloy melt is any one of the above combinations (1)-(4);

[0023] Step S2: Solidify the initial alloy melt into an initial alloy strip; the solidification structure of the initial alloy strip includes a matrix phase and a dispersed particle phase; the melting point of the matrix phase is lower than that of the dispersed particle phase, and the dispersed particle phase is coated in the matrix phase; during the solidification process of the initial alloy melt, the impurity element T in the initial alloy melt is redistributed between the dispersed particle phase and the matrix phase and enriched in the matrix phase, thereby purifying the dispersed particle phase;

[0024] When the average composition of the initial alloy melt is as described in combination (1) of step S1, the composition of the dispersed particle phase in the initial alloy strip is mainly (M x D y ) x1 T z1 , and the average composition of the matrix phase is mainly A x2 T z2 ; and 98.5% ≤ x1 < 100%, 0 < z1 ≤ 1.5%; 80% ≤ x2 < 100%, 0 < z2 ≤ 20%; z1 < d < z2, 2z1 < z2; x1, z1, x2, z2 respectively represent the atomic percentage contents of the corresponding constituent elements;

[0025] Preferably, when the average composition of the initial alloy melt is as described in combination (1) of step S1, the dispersed particle phase with the composition mainly (M x D y ) x1 T z1 does not contain element A.

[0026] Preferably, when the average composition of the initial alloy melt is as described in combination (1) of step S1, the composition of the dispersed particle phase in the initial alloy strip is (M x D y ) x1 T z1 , and the average composition of the matrix phase is A x2 T z2 ;

[0027] When the average composition of the initial alloy melt is as described in combination (2) or combination (3) of step S1, the composition of the dispersed particle phase in the initial alloy strip is mainly M x1 T z1 , and the average composition of the matrix phase is mainly A x2 T z2 ; and 98.5% ≤ x1 < 100%, 0 < z1 ≤ 1.5%; 80% ≤ x2 < 100%, 0 < z2 ≤ 20%; z1 < d < z2, 2z1 < z2; x1, z1, x2, z2 respectively represent the atomic percentage contents of the corresponding constituent elements;

[0028] Preferably, when the average composition of the initial alloy melt is as described in combination (2) or combination (3) of step S1, the composition is mainly M x1 T z1 The dispersed particle phase of does not contain element A.

[0029] Preferably, when the average composition of the initial alloy melt is as described in combination (2) or combination (3) of step S1, the composition of the dispersed particle phase in the initial alloy strip is M x1 T z1 , and the average composition of the matrix phase is A x2 T z2 ;

[0030] When the average composition of the initial alloy melt is as described in combination (4) of step S1, the composition of the dispersed particle phase in the initial alloy strip is mainly M x1 Al y1 T z1 , and the average composition of the matrix phase is mainly A x2 Al y2 T z2 ; and 77.8% ≤ x1 ≤ 99.8%, 0.1% ≤ y1 ≤ 22%, 0 < z1 ≤ 1.5%; 69.8% ≤ x2 ≤ 99.7%, 0.2% ≤ y2 ≤ 30%, 0 < z2 ≤ 20%, z1 < d < z2, 2z1 < z2, y1 < y2, where x1, y1, z1, x2, y2, z2 respectively represent the atomic percentage contents of the corresponding constituent elements;

[0031] Preferably, when the average composition of the initial alloy melt is as described in combination (4) of step S1, the composition is mainly M x1 Al y1 T z1 The dispersed particle phase of does not contain element A.

[0032] Preferably, when the average composition of the initial alloy melt is as described in combination (4) of step S1, the composition of the dispersed particle phase in the initial alloy strip is M x1 Al y1 T z1 , and the average composition of the matrix phase is A x2 Al y2 T z2 ;

[0033] Step S3, remove the matrix phase in the initial alloy strip, and retain the dispersed particle phase that cannot be removed simultaneously during the removal of the matrix phase, and collect the shed dispersed particle phase, thus obtaining the high-purity target powder material composed of the original dispersed particles.

[0034] In the said step S1,

[0035] Furthermore, the sources of T impurity elements in the initial alloy melt include: impurities introduced by the initial alloy raw materials, and impurities introduced by the atmosphere or crucible during the smelting process. Among them, the impurities introduced by the atmosphere refer to impurities such as O, N, H, etc. in the ambient atmosphere absorbed by the alloy melt.

[0036] Furthermore, T is an impurity element and includes at least one of O, H, N, P, S, F, Cl, I, Br; and the total content of these impurity elements is the content of T impurity elements;

[0037] Furthermore, if the raw materials are various single substances or master alloys containing impurity elements, they can be melted according to the ratio to prepare the initial alloy melt. If the provided raw materials are directly alloy raw materials corresponding to the components of the initial alloy melt, they can be remelted to obtain the initial alloy melt.

[0038] Furthermore, the initial alloy raw materials include M-T raw materials containing impurity element T. For example, when M is Ti and T includes O, the M-T raw material includes Ti-O raw materials containing O impurities.

[0039] Furthermore, in step S1, the combination of A and M in the average composition of the initial alloy melt is extremely important. The selection principle is to ensure that no intermetallic compound is formed between A and M during the solidification process of the alloy melt; or even if M can form a high-melting-point intermetallic compound with other elements (D), no intermetallic compound is formed between A and M. In this way, two-phase separation of the matrix phase mainly composed of A and the particle phase mainly composed of M can be achieved during the solidification process of the initial alloy melt, which is beneficial to the subsequent preparation of powder materials mainly composed of M.

[0040] In step S2,

[0041] Furthermore, the initial alloy strip does not contain intermetallic compounds composed of A and M;

[0042] Furthermore, the ways of solidifying the alloy melt include the strip casting method and the continuous casting method; generally speaking, thinner initial alloy strips can be obtained by the strip casting method; thicker alloy strips can be obtained by the continuous casting method.

[0043] Whether it is the thin alloy strip obtained by the strip casting method or the thick alloy strip obtained by the continuous casting method, their morphologies are completely different from those of the alloy ingots obtained by the ordinary casting method. The alloy ingots obtained by the ordinary casting method generally have no obvious differences in scale in terms of length, width, and thickness.

[0044] Further, the thickness of the initial alloy strip ranges from 5 μm to 50 mm; further, the thickness of the initial alloy strip ranges from 5 μm to 5 mm; preferably, the thickness of the initial alloy strip ranges from 5 μm to 1 mm; more preferably, the thickness of the initial alloy strip ranges from 5 μm to 200 μm; more preferably, the thickness of the initial alloy strip ranges from 5 μm to 20 μm.

[0045] It should be noted that when the thickness of the initial alloy strip is in millimeters, it can also be referred to as an alloy sheet.

[0046] Further, the width of the cross-section of the initial alloy strip is more than 2 times its thickness.

[0047] Further, the length of the initial alloy strip is more than 10 times its thickness.

[0048] Preferably, the length of the initial alloy strip is more than 50 times its thickness.

[0049] Preferably, the length of the initial alloy strip is more than 100 times its thickness.

[0050] Further, the solidification rate of the initial alloy melt is 1 K / s to 10 7 K / s.

[0051] Further, the particle size of the dispersed particle phase is related to the solidification rate of the initial alloy melt; generally speaking, the particle size of the dispersed particle phase is negatively correlated with the solidification rate of the initial alloy melt, that is, the greater the solidification rate of the initial alloy melt, the smaller the particle size of the dispersed particle phase.

[0052] Further, the particle size range of the dispersed particle phase is 2 nm to 3 mm; further, the particle size range of the dispersed particle phase is 2 nm to 500 μm; preferably, the particle size range of the dispersed particle phase is 2 nm to 99 μm; more preferably, the particle size range of the dispersed particle phase is 2 nm to 5 μm; more preferably, the particle size range of the dispersed particle phase is 2 nm to 200 nm; more preferably, the particle size range of the dispersed particle phase is 2 nm to 100 nm.

[0053] Further, when the solidification rate of the initial alloy melt is 10 5 K / s to 10 7 K / s, dispersed particles with a particle size mainly in the nanometer scale can be obtained.

[0054] Further, when the solidification rate of the initial alloy melt is 10 4 K / s to 10 5When the rate is K / s, dispersed particles with a mainly sub-micron scale particle size can be obtained.

[0055] Further, the solidification rate of the initial alloy melt is 10 2 K / s to 10 4 K / s, and dispersed particles with a mainly micron scale particle size can be obtained.

[0056] Further, when the solidification rate of the initial alloy melt is 1 K / s to 10 2 K / s, dispersed particles with a mainly millimeter scale particle size can be obtained.

[0057] Further, the particle shape of the dispersed particle phase is not limited, and may include at least one of dendritic, spherical, near-spherical, square, cake-shaped, rod-shaped; when the particle shape is rod-shaped, the size of the particle specifically refers to the diameter size of the rod cross-section.

[0058] Further, when the dispersed particles are at the nano-scale or sub-micron scale, spherical or near-spherical particles are likely to be obtained; when the dispersed particles are at the micron scale and above, dendritic particles are likely to be obtained.

[0059] Further, the dispersed particle phase solidifies and precipitates from the initial alloy melt. According to the nucleation and growth theory, whether it is a near-spherical nano-particle that has just nucleated and grown, or a micron-scale or millimeter-scale dendritic particle that has fully grown, its crystal growth has a fixed orientation relationship, so that each precipitated single particle is mainly composed of a single crystal.

[0060] When the volume percentage of the dispersed particles in the entire initial alloy strip is relatively high, during the endogenous precipitation process of the single crystal particles, the situation of two or more particles merging cannot be excluded. If two or more single crystal particles are only soft-aggregated, adsorbed to each other, or only in contact with a small part and connected together, and do not fully combine into one particle through a normal grain boundary like a polycrystalline material, they are still two single crystal particles. Its characteristic is that after removing the matrix phase in the subsequent process, these single crystal particles can be easily separated by techniques including ultrasonic dispersion treatment, jet milling, etc. For normal ductile metal or alloy polycrystalline materials, it is difficult to separate the grain boundaries by techniques including ultrasonic dispersion treatment, jet milling, etc.

[0061] Preferably, the proportion of the number of single crystal particles in the dispersed particles in the initial alloy strip in all the number of dispersed particles is not less than 60%.

[0062] As a further preference, the proportion of the number of single crystal particles in the dispersed particles in all the number of dispersed particles is not less than 90%.

[0063] Further, for a certain determined initial alloy strip, the volume percentage content of the dispersed particle phase in the initial alloy strip can be calculated and determined by combining the corresponding initial alloy melt composition, dispersed particle phase composition, matrix phase composition, elemental atomic weight, density parameter, etc.

[0064] When the main element of the matrix phase is a large atomic element, the matrix phase can obtain a higher volume percentage content with a smaller atomic ratio percentage. For example, for an initial alloy strip with an atomic percentage composition of La 25 Fe 75 (for the convenience of calculation, the presence of impurities is not considered), the weight percentage contents of La and Fe are 45.33 wt% and 54.67 wt% respectively. Combining their densities of 6.2 g / cm 3 and 7.8 g / cm 3 , the volume percentage contents of La and Fe in the initial alloy strip with an atomic percentage composition of La 25 Fe 75 can be calculated to be 51 vol.% and 49 vol.% respectively. This shows that: even if the atomic percentage content of Fe in the La-Fe alloy is as high as 75 at.%, its volume percentage content is still lower than 50 vol.%, which is beneficial to the dispersed distribution of Fe particles in the initial alloy strip.

[0065] Further, the volume percentage content of the dispersed particle phase in its corresponding initial alloy strip is not higher than 50% vol.

[0066] Further, the atomic percentage content z1 of the T impurity element in the dispersed particles is less than the atomic percentage content of the T impurity element in the M-T raw material.

[0067] Further, z1 < d < z2, and 2z1 < z2,

[0068] Preferably, z1 < d < z2, and 3z1 < z2,

[0069] Preferably, 0 < z1 < d < z2, 3z1 < z2, and 0 < z1 ≤ 1.5%; that is, the T impurity content in the dispersed particles is lower than the T impurity content in the initial alloy melt, and three times the T impurity content in the dispersed particles is still lower than the T impurity content in the matrix phase;

[0070] Preferably, 0 < z1 < d < z2, 3z1 < z2, and 0 < z1 ≤ 0.75%.

[0071] The present invention uses atomic percentage content to express the content of T impurities. By characterizing the composition of each element through the atomic percentage content of the element, the increase and decrease of the element content can be accurately expressed through the concept of the amount of substance, such as the increase and decrease and changes of impurity elements. If the mass percentage content of the element (or ppm concept) is used to characterize the content of each element, due to the different atomic weights of each element, incorrect conclusions are likely to be drawn. For example, for an alloy with an atomic percentage content of Ti 45 Gd 45 O 10 containing 100 atoms, the atomic percentage content of O is 10 at%. Divide these 100 atoms into Ti 45 O4 (with an atomic percentage composition of Ti 91.8 O 8.2 ) and Gd 45 O6 (with an atomic percentage composition of Gd 88.2 O 11.8 ). The atomic percentage content of oxygen in Gd 45 O6 increases to 11.8 at%, and the atomic percentage content of oxygen in Ti 45 O4 decreases to 8.2 at%. It can accurately express that O is enriched in Gd. However, if the mass percentage content of O is used to measure, the mass percentage content of O in Ti 45 Gd 45 O 10 is 1.70 wt%, and the mass percentage content of O in Ti 45 O4 and Gd 45 O6 are 2.9 wt.% and 1.34 wt.% respectively. It will lead to the incorrect conclusion that the O content in Ti 45 O4 is significantly higher than that in Gd 45 O6.

[0072] In the step S3,

[0073] Further, the method for removing the matrix phase in the alloy strip includes at least one of acid reaction removal, alkali reaction removal, and vacuum volatilization removal.

[0074] The composition and concentration of the acid solution and the alkali solution are not specifically limited, as long as they can ensure the removal of the matrix phase while retaining the dispersed particle phase.

[0075] The temperature and vacuum degree of the vacuum treatment are not specifically limited, as long as they can ensure the removal of the matrix phase while retaining the dispersed particle phase.

[0076] Further, the method for removing the matrix phase in the initial alloy strip includes natural oxidation - pulverization and exfoliation removal of the matrix phase.

[0077] When the matrix phase is an element that is extremely prone to natural oxidation with oxygen, such as La, Ce, etc., through the natural oxidation and pulverization process of the matrix phase, the matrix phase can be separated from the dispersed particle phase. With the assistance of other technical means, such as magnetic separation, the dispersed particle phase with magnetism, for example, can be separated from the natural oxide of the matrix phase.

[0078] Furthermore, since the target powder material is the dispersed particle phase detached from the initial alloy strip, the composition, particle size, etc. of the target powder material are equivalent to those of the corresponding dispersed particle phase.

[0079] Furthermore, the particle size range of the target powder material is 2 nm to 3 mm; preferably, the particle size range of the target powder material is 2 nm to 500 μm; preferably, the particle size range of the target powder material is 2 nm to 99 μm; more preferably, the particle size range of the target powder material is 2 nm to 5 μm; more preferably, the particle size range of the target powder material is 2 nm to 200 nm; more preferably, the particle size range of the target powder material is 2 nm to 100 nm.

[0080] Furthermore, after the initial alloy strip reacts with the acid solution, the dispersed particles detach from the initial alloy strip, and after cleaning and drying, the high-purity target powder material is obtained.

[0081] Preferably, when the average composition of the initial alloy melt is as described in combination (1) of step S1, the composition of the high-purity target powder material is mainly (M x D y ) x1 T z1 ;

[0082] Furthermore, when the average composition of the initial alloy melt is as described in combination (1) of step S1, the dispersed particles mainly composed of (M x D y ) x1 T z1 do not contain element A;

[0083] Preferably, when the average composition of the initial alloy melt is as described in combination (1) of step S1, the composition of the high-purity target powder material is (M x D y ) x1 T z1 ;

[0084] Furthermore, when the average composition of the initial alloy melt is as described in combination (2) or (3) of step S1, the composition of the high-purity target powder material is mainly M x1 T z1 ;

[0085] Preferably, when the average composition of the initial alloy melt is as described in combination (2) or (3) of step S1, the composition is mainly M x1 T z1 The dispersed particles of do not contain element A;

[0086] Preferably, when the average composition of the initial alloy melt is as described in combination (2) or (3) of step S1, the composition of the high-purity target powder material is M x1 T z1 ;

[0087] Furthermore, when the average composition of the initial alloy melt is as described in combination (4) of step S1, the composition of the high-purity target powder material is mainly M x1 Al y1 T z1 .

[0088] Preferably, when the average composition of the initial alloy melt is as described in combination (4) of step S1, the composition is mainly M x1 Al y1 T z1 The dispersed particles of do not contain element A;

[0089] Preferably, when the average composition of the initial alloy melt is as described in combination (4) of step S1, the composition of the high-purity target powder material is M x1 Al y1 T z1 .

[0090] Furthermore, the atomic percentage content of impurity element T in the target metal powder does not exceed 1.5%;

[0091] Preferably, the atomic percentage content of impurity element T in the target metal powder does not exceed 0.75%.

[0092] Furthermore, after step S3, the following steps are also carried out: After screening the high-purity powder material, select the high-purity powder material with a particle size range of 5 μm to 200 μm for plasma spheroidization treatment to obtain a spherical high-purity powder material;

[0093] The present invention also relates to the application of the high-purity powder material or spherical high-purity powder material obtained by the above preparation method in catalytic materials, powder metallurgy, composite materials, wave-absorbing materials, sterilization materials, metal injection molding, 3D printing, coatings.

[0094] Furthermore, for the application of the spherical high-purity powder material obtained by the above preparation method in the field of metal powder 3D printing, it is characterized in that the particle size range of the spherical high-purity powder material is 10 μm to 200 μm.

[0095] Furthermore, the application of the high-purity powder material obtained by the above preparation method in metal injection molding and powder metallurgy is characterized in that the particle size range of the high-purity powder material is 0.1 μm to 200 μm.

[0096] Furthermore, the application of the high-purity powder material obtained by the above preparation method in coatings is characterized in that the particle size range of the high-purity powder material is 2 nm to 5 μm.

[0097] The present invention also relates to an alloy strip, which is characterized in that it comprises endo-powder and a coating; the solidification structure of the alloy strip includes a matrix phase and a dispersed particle phase, the matrix phase is the coating, and the dispersed particle phase is the endo-powder; the melting point of the coating is lower than that of the endo-powder, and the endo-powder is coated in the coating;

[0098] The chemical composition and structure of the alloy strip include any one of the following four combinations:

[0099] 1) The main component of the endo-powder in the alloy strip is (M x D y ) x1 T z1 , and the average composition of the coating is mainly A x2 T z2 ; and 98.5% ≤ x1 < 100%, 0 < z1 ≤ 1.5%; 80% ≤ x2 < 100%, 0 < z2 ≤ 20%; z1 < d < z2, 2z1 < z2; x1, z1, x2, z2 respectively represent the atomic percentage contents of the corresponding constituent elements; wherein, A includes at least one of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, M includes at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti, D includes at least one of Fe, Co, Ni; T includes at least one of O, H, N, P, S, F, Cl, I, Br; x, y represent the atomic percentage contents of the corresponding constituent elements, 10% ≤ x ≤ 55%, 45% ≤ y ≤ 90%; furthermore, the molar ratio x:y = 0.9 to 1.1; preferably, x = y = 50%, that is, the molar ratio x:y = 1:1;

[0100] Preferably, the endo-powder with the main component of (M x D y ) x1 T z1 in the alloy strip does not contain element A.

[0101] Preferably, the composition of the endo-powder in the alloy strip is (M x D y )x1 T z1 , the average composition of the coating is A x2 T z2 ;

[0102] 2) The composition of the in-situ powder in the alloy strip is mainly M x1 T z1 , the average composition of the coating is mainly A x2 T z2 ; and 98.5% ≤ x1 < 100%, 0 < z1 ≤ 1.5%; 80% ≤ x2 < 100%, 0 < z2 ≤ 20%; z1 < d < z2, 2z1 < z2; x1, z1, x2, z2 respectively represent the atomic percentage contents of the corresponding constituent elements; wherein, A contains at least one of Mg, Ca, Li, Na, K, Cu, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and M contains at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti; T contains at least one of O, H, N, P, S, F, Cl, I, Br;

[0103] Preferably, when M contains at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti, A contains one of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu;

[0104] Preferably, when M contains at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti, A contains Cu;

[0105] Preferably, the composition of the in-situ powder in the alloy strip is mainly M x1 T z1 The in-situ powder does not contain element A;

[0106] Preferably, the composition of the in-situ powder in the alloy strip is M x1 T z1 , the average composition of the coating is A x2 T z2 ;

[0107] 3) The composition of the in-situ powder in the alloy strip is mainly M x1 T z1 , the average composition of the coating is mainly A x2 T z2; and 98.5% ≤ x1 < 100%, 0 < z1 ≤ 1.5%; 80% ≤ x2 < 100%, 0 < z2 ≤ 20%; z1 < d < z2, 2z1 < z2; x1, z1, x2, and z2 respectively represent the atomic percentage contents of the corresponding constituent elements; wherein, A comprises at least one of Zn, Mg, Sn, Pb, Ga, In, Al, La, Ge, Cu, K, Na, and Li, and M comprises at least one of B, Bi, Fe, Ni, Cu, Ag, Si, Ge, Cr, and V;

[0108] Preferably, when M comprises B, A comprises at least one of Sn, Ge, Cu, and Zn; when M comprises Bi, A comprises at least one of Sn, Ga, and Al;

[0109] Preferably, when M comprises at least one of Fe, Ni, Cu, and Ag, A comprises at least one of La, In, Na, K, Li, Pb, and Mg; preferably, when M comprises at least one of Fe and Ni, A comprises at least one of La, In, Na, K, Li, and Mg; when M comprises at least one of Cu and Ag, A comprises at least one of Pb, Na, K, and Li;

[0110] Preferably, when M comprises at least one of Si and Ge, A comprises at least one of Zn, Sn, Pb, Ga, In, and Al;

[0111] Preferably, when M comprises at least one of Cr and V, A comprises Zn;

[0112] Preferably, the main component of the alloy strip is M x1 T z1 The internal powder of T does not contain element A.

[0113] Preferably, the internal powder in the alloy strip has a composition of M x1 T z1 and the average composition of the coating is A x2 T z2 ;

[0114] 4) The main component of the internal powder in the alloy strip is M x1 Al y1 T z1 and the average composition of the coating is mainly A x2 Al y2 T z2; and 77.8% ≤ x1 ≤ 99.8%, 0.1% ≤ y1 ≤ 22%, 0 < z1 ≤ 1.5%; 69.8% ≤ x2 ≤ 99.7%, 0.2% ≤ y2 ≤ 30%, 0 < z2 ≤ 20%, z1 < d < z2, 2z1 < z2, y1 < y2, where x1, y1, z1, x2, y2, z2 respectively represent the atomic percentage contents of the corresponding constituent elements; wherein, A comprises at least one of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu; M comprises at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti; Al is aluminum;

[0115] Preferably, the main component of the alloy strip is M x1 Al y1 T z1 The endogenous powder of does not contain element A;

[0116] Preferably, the composition of the endogenous powder in the alloy strip is M x1 Al y1 T z1 , and the average composition of the coating is A x2 Al y2 T z2 ;

[0117] Preferably, the chemical composition and structure of the alloy strip are any one of the above four combinations 1)-4);

[0118] Furthermore, the thickness range of the alloy strip is 5 μm to 50 mm; preferably, the thickness range of the alloy strip is 5 μm to 5 mm; preferably, the thickness range of the alloy strip is 5 μm to 1 mm; further preferably, the thickness range of the alloy strip is 5 μm to 200 μm; further preferably, the thickness range of the alloy strip is 5 μm to 20 μm.

[0119] Furthermore, the width of the cross-section of the alloy strip is more than 2 times its thickness; furthermore, the length of the initial alloy strip is more than 10 times its thickness; preferably, the length of the initial alloy strip is more than 50 times its thickness; preferably, the length of the initial alloy strip is more than 100 times its thickness.

[0120] Further, the particle size range of the endogenic powder is 2 nm to 3 mm; preferably, the particle size range of the endogenic powder is 2 nm to 500 μm; preferably, the particle size range of the endogenic powder is 2 nm to 99 μm; more preferably, the particle size range of the endogenic powder is 2 nm to 10 μm; more preferably, the particle size range of the endogenic powder is 2 nm to 1 μm; more preferably, the particle size range of the endogenic powder is 2 nm to 200 nm; more preferably, the particle size range of the endogenic powder is 2 nm to 100 nm.

[0121] Further, the shape of the endogenic powder includes at least one of dendritic, spherical, near-spherical, square, cake-shaped, and rod-shaped.

[0122] Further, the proportion of the number of single crystal particles in the endogenic powder in the alloy strip is not less than 60% of the total number of all endogenic powder.

[0123] Further, the volume percentage content of the endogenic powder in the alloy strip does not exceed 50%.

[0124] Further, 2z2 ≤ z1, and 0 ≤ z2 ≤ 1.5%;

[0125] Preferably, 3z2 < z1, and 0 < z2 ≤ 1.5%;

[0126] More preferably, 3z2 < z1, and 0 < z2 ≤ 0.75%.

[0127] It should be noted that in the solution of the present invention, A, M, D or T may also contain other elements or impurity elements other than the above-listed elements. As long as the introduction of these elements or the change in their content does not cause a "qualitative change" in the initial alloy solidification process and law, it does not affect the implementation of the above technical solution of the present invention.

[0128] Specifically, the fact that the initial alloy solidification process and law do not undergo a "qualitative change" means that when A, M, D or T contains other elements or impurity elements other than the above-listed elements, the following factual processes and laws listed in 1)-3) still exist:

[0129] 1) The initial alloy strip does not contain intermetallic compounds mainly composed of A and M, or A and D;

[0130] 2) The solidification structure of the initial alloy strip includes a matrix phase and a dispersed particle phase; the melting point of the matrix phase is lower than that of the dispersed particle phase, and the dispersed particle phase is coated in the matrix phase;

[0131] 3) When the content of impurity T in the initial alloy melt is not 0, the content of impurity T in the dispersed particle phase is lower than that in the initial alloy melt, and twice the content of impurity T in the dispersed particle phase is still lower than that in the matrix phase.

[0132] The technical solution of the present invention has the following beneficial effects:

[0133] First, through ingenious alloy design, phase separation occurs during the solidification of the initial alloy melt, enabling the formation of endogenous particles of a target component with a certain particle size during the solidification process of the initial alloy melt and allowing for separation through subsequent processes. Generally speaking, it is relatively easy to prepare nano-metal particles through a bottom-up chemical method such as chemical reduction. However, when the particle size increases to hundreds of nanometers or even micrometers, it becomes difficult to prepare. Through top-down physical methods such as atomization and ball milling, it is relatively easy to prepare metal particles with a size of dozens of micrometers or hundreds of micrometers. However, when the particle size is reduced to hundreds of nanometers to a few micrometers, it is also very difficult to prepare. The technical solution of the present invention can very easily prepare target metal powder particles with nano-scale, sub-micron scale, micron scale, or even millimeter scale according to the different cooling rates during the solidification process of the initial alloy strip, breaking through the above technical difficulties and having great advantages.

[0134] Second, it realizes the obtaining of high-purity target powder materials from low-purity raw materials and points out a new way for preparing high-purity powder materials from low-purity raw materials, which has positive significance. The improvement of the purity of the target powder material of the present invention is mainly achieved through the following three mechanisms: 1) The "absorption" effect of the highly active matrix main element (such as RE rare earth element) on the impurity elements in the initial alloy melt. Since the matrix element is generally a highly active and low-melting-point element, it has a very strong affinity with the impurity element T during the melting and solidification processes of the alloy melt. This can cause the impurity element T in the initial alloy melt to either enter the matrix phase mainly composed of the matrix main element more or form a slag with the matrix main element in the molten state and be separated from the alloy melt; 2) During the nucleation and growth process of the endogenously precipitated dispersed particle phase, the impurity element T will be discharged into the remaining melt. As long as the endogenously precipitated dispersed particle phase does not precipitate later than the matrix phase during the solidification process, its impurities will be enriched in the last solidified part of the melt, that is, the part of the melt mainly composed of the matrix main element and solidifying to form the matrix phase. 3) Due to the presence of the second-phase matrix, the impurities related to the crucible that enter the melt due to the interaction between the crucible and the melt during the smelting process are generally concentrated in the second-phase matrix, which further reduces the impurity content in the target powder material, further reduces the requirements for the crucible during the smelting process, and greatly reduces the production cost.

[0135] Thirdly, the target metal powder mainly composed of single crystal particles can be obtained. Compared with polycrystalline powders, single crystal powders can achieve many remarkable and beneficial effects. During the solidification process of the initial alloy melt, each endogenous dispersed particle nucleates at a certain position in the melt and grows according to a specific atomic arrangement. By controlling the volume percentage of the dispersed particle phase in the initial alloy strip to not exceed 50%, ensuring that each endogenous particle can be dispersed, it is difficult for the endogenous particles to merge and grow with each other. Therefore, most of the finally obtained dispersed particle phases are single crystal phases. Even for dendritic particles with a scale as large as dozens of micrometers or millimeters, the growth direction of each secondary dendrite maintains a certain phase relationship with the growth direction of the primary dendrite, and it still belongs to single crystal particles. For polycrystalline materials, their grain boundaries generally tend to contain impurity elements discharged from the crystal interior during the solidification process, so it is difficult to obtain high-purity polycrystalline powder materials. When the target metal powder is mainly composed of single crystal particles, its purity can surely be guaranteed. Moreover, the surface atoms of single crystal particles have specific arrangements, such as (111) plane arrangement, etc. These specific arrangements will endow the target metal powder with special mechanical, physical, and chemical properties, thus producing beneficial effects.

[0136] Fourth, when the average composition of the initial alloy melt is as described in the combination (4) of step S1, the solid solution of Al element in a metal or alloy material containing elements such as W, Cr, Mo, V, Ta, Nb, Zr, Hf, and Ti is achieved. In the above alloy material, the addition of Al element plays a very important role. For example, the most widely used titanium alloy at present is the Ti6Al4V alloy. For Ti6Al4V alloy powder, generally, the Ti6Al4V alloy melt is smelted and then the Ti6Al4V alloy powder is obtained through atomization powder making technology. Limited by the atomization powder making technology, it is very difficult to obtain ultra-fine Ti6Al4V alloy powder, and even nano-scale Ti6Al4V alloy powder cannot be obtained through the atomization powder making technology. Therefore, it is of great significance to realize the addition of Al element in the Ti-V alloy through the "phase removal method" involved in the present invention and prepare Ti6Al4V alloy powder with various particle sizes. The present invention discovers that when a considerable amount of Al element (which can exceed 10 at.% or even higher) is added to an alloy composed of A (A = at least one of rare earth elements RE) and M (M = at least one of elements such as W, Cr, Mo, V, Ta, Nb, Zr, Hf, and Ti), the Al element in the alloy solidification structure can exist simultaneously in the matrix phase mainly composed of RE and the dispersed particle phase mainly composed of M through a certain content distribution relationship. Since the RE-Al matrix phase can be easily removed by acid reaction, while the Al in the Al-containing dispersed particles mainly composed of M is protected by the inert M element and will not be easily removed by acid reaction (such as the Ti6Al4V alloy has good acid corrosion resistance), this makes it possible to prepare Al-containing titanium alloy powder by removing the matrix phase through acid reaction.

[0137] Fifth, the alloy strip composed of the endogenic powder and the coating (matrix phase) creatively uses the in-situ generated matrix phase to wrap the endogenic powder, maintaining the high purity and high activity of the endogenic powder. Specifically, whether it is metal or alloy powder prepared by traditional chemical methods or physical methods, especially nanopowders with extremely large specific surface areas, are extremely prone to natural oxidation and face difficulties in powder preservation. To address this problem, after the alloy strip composed of the endogenic metal powder and the coating (matrix phase) is prepared in the technical solution involved in the present invention, the coating is not removed immediately, but the coating is directly used to protect the endogenic metal powder from natural oxidation. This alloy strip composed of the endogenic metal powder and the coating can be directly used as the raw material for downstream production, and thus has the potential to become a special type of product. When high-purity powder is required for downstream production, according to the characteristics of the next process, an appropriate timing can be selected and in an appropriate environment, the endogenic metal powder can be released from the coating in the alloy strip, and then the released endogenic powder can enter the next production process in the shortest possible time, thereby greatly reducing the chance of the endogenic metal powder being contaminated by impurities such as oxygen. For example, when the endogenic metal powder is nanopowder, it can be compounded with resin simultaneously or immediately after the endogenic metal powder is released from the coating, thereby preparing a resin-based composite material added with highly active endogenic metal powder.

[0138] Sixth, the solid alloy obtained by solidification in step S2 is in strip shape, which ensures the uniformity of the product shape and the feasibility of large-scale production. When the alloy strip is a thin alloy strip, it can be prepared by the melt-spinning method. As long as the flow rate of the alloy melt flowing towards the rotating roll is fixed and the rotation speed of the rotating roll is fixed, an alloy thin strip with uniform thickness can be obtained, and this preparation process can be carried out continuously, which is conducive to large-scale production. When the alloy strip is a thick alloy strip, it can be prepared by the mature continuous casting method. The principle of continuous casting is similar to that of the melt-spinning method, and a continuous and thick strip with uniform thickness can also be obtained from the melt, and the preparation process can also be carried out continuously, which is conducive to large-scale production. When the thickness of the alloy strip is uniform, the cooling rate is also relatively uniform, and the particle size of the dispersed particles obtained is also relatively uniform. In contrast, if the solid alloy obtained by solidification is in ingot shape, according to common sense, the ingot does not have a uniform thickness, nor obvious length and endpoints, which generally leads to difficult heat dissipation of the internal melt and is likely to obtain abnormally large endogenic particles. Such an operation is only required when simply collecting and purifying large endogenic particles. Moreover, ordinary ingots are difficult to produce continuously. Therefore, the alloy strip obtained by solidification in the present invention is suitable for the subsequent preparation of powder materials by the "phase removal method".

[0139] Therefore, the preparation method of the present invention has the characteristics of simple process, easy operation, and low cost, and can prepare various high-purity powder materials including nanoscale, sub-micron scale, and micron scale, and has good application prospects in the fields of catalytic materials, powder metallurgy, composite materials, wave-absorbing materials, sterilization materials, magnetic materials, metal injection molding, 3D printing, coatings, etc.

[0140] As an alternative, the present invention also provides a method for preparing high-purity metal powder, which comprises the following steps:

[0141] Step 1: Select an initial alloy, melt the initial alloy raw materials according to the composition ratio of the initial alloy to obtain a uniform alloy melt, and then prepare the alloy melt into an alloy strip by rapid solidification technology;

[0142] When the composition ratio of the initial alloy is A a M b At this time, A is selected from at least one of Mg, Ca, Li, Na, K, Zn, Pb, Sn, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and M is selected from at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti, Fe, Co, Ni, Cu, Ag, Si, Ge, and M does not contain only Fe alone; where a and b represent the atomic percentage contents of the corresponding constituent elements, 45% < b ≤ 75%, a + b = 100%; and A a M b The solidification structure of the alloy strip does not contain intermetallic compounds composed of A and M, and its solidification structure consists of a matrix phase with a composition of A and a dispersed particle phase with a composition of M;

[0143] When the composition ratio of the initial alloy is La a Fe b At this time, 40% < b ≤ 75%, a + b = 100%, a and b represent the atomic percentage contents of the corresponding constituent elements; and La a Fe b The solidification structure of the alloy strip does not contain intermetallic compounds composed of La and Fe, and its solidification structure consists of a matrix phase with a composition of La and a dispersed particle phase with a composition of Fe;

[0144] When the composition ratio of the initial alloy is A a M b Al cWhen, A is selected from at least one of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Al is aluminum, and M is selected from at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti, Fe, Co, Ni; where a, b, and c respectively represent the atomic percentage contents of the corresponding constituent elements, 35% < b ≤ 75%, 0.1% ≤ c ≤ 30%, and a + b + c = 100%; and A a M b Al c The solidification structure of the alloy strip does not contain intermetallic compounds composed of A and M, and its solidification structure consists of dispersed particle phases with a composition of M x1 Al y1 and matrix phases with a composition of A x2 Al y2 ; where x1, y1, x2, and y2 respectively represent the atomic percentage contents of the corresponding constituent elements, and 0.1% ≤ y1 ≤ 25%, 0.1% ≤ y2 ≤ 35%, x1 + y1 = 100%, and x2 + y2 = 100%;

[0145] During the solidification process of the initial alloy melt, impurity elements in the alloy melt and impurity elements introduced during the solidification process are enriched in the matrix phase, thereby purifying the dispersed particle phase;

[0146] Step 2: Remove the matrix phase in the alloy strip and retain the dispersed particle phase, and the impurity elements enriched in the matrix phase are removed accordingly, that is, high-purity target metal powder composed of dispersed particles is obtained.

[0147] Through the above technical solutions, the preparation of ultra-fine and low-impurity-content metal powder can be realized. In terms of obtaining fine powder, the higher the solidification rate of the alloy melt, the smaller the dispersed particle phase in the solidification structure of the obtained alloy strip. Therefore, the present invention can obtain nano-scale, sub-micron-scale, and micron-scale dispersed particle phases respectively by controlling the solidification rate, and then obtain target metal powder with corresponding particle size by removing the matrix phase, greatly reducing the preparation cost of ultra-fine metal powder. In terms of impurity control, since the matrix phase is generally composed of low-melting-point and high-activity elements, this enables impurity elements to be enriched in the matrix phase during alloy melting and rapid solidification, thereby purifying and protecting the dispersed particle phase and realizing the preparation of high-purity target metal powder.

[0148] In addition, in the selection of alloy component ratios, although the A a M b , La a Fe b and A a M b Al cThe maximum value of b (atomic percentage content) in the alloy is 75%, but this does not affect the dispersed precipitation of the dispersed particles in the matrix phase. Since the matrix phase of the present invention is mainly composed of large atomic elements, even if the atomic percentage content of the matrix phase is less than 50%, its volume percentage content in the alloy strip can be much higher than its atomic percentage content. Such as La 25 Fe 75 (atomic ratio composition) In the solidified structure of the alloy, the volume percentage content of the La matrix can still reach 51%. When the solidification rate of the alloy melt is fast enough and the Fe particles are nanoscale, La 25 Fe 75 The Fe particles in the solidified structure of the alloy do not have time to merge and grow, and can still be dispersed and precipitated.

[0149] Furthermore, in order to ensure the dispersed precipitation of the dispersed particles, the volume percentage content of the matrix phase in the alloy strip is not less than 44%.

[0150] Furthermore, the rapid solidification technology includes the melt spinning method of the alloy melt, and the solidification rate of the alloy melt is 50 K / s to 10 7 K / s. When the solidification rate is higher than 10 5 K / s, nanoscale dispersed particle phases can be obtained; when the solidification rate is 10 3 K / s to 10 5 K / s, sub-micron scale dispersed particle phases can be obtained; when the solidification rate is lower than 10 3 K / s, micron scale dispersed particle phases can be obtained.

[0151] Furthermore, the thickness of the alloy strip is 5 μm to 5 mm.

[0152] Furthermore, the shape of the dispersed particle phase includes at least one of dendritic, spherical, near-spherical, square, cake-shaped, rod-shaped, and the particle size ranges from 2 nm to 200 μm.

[0153] Furthermore, the impurity elements in the alloy melt and the impurity elements introduced during the solidification process include at least one of H, O, N, S, P, F, Cl, I, Br.

[0154] Furthermore, the method for removing the matrix phase in the alloy strip includes at least one of acid reaction removal, alkali reaction removal, and vacuum volatilization removal. The composition and concentration of the acid solution and the alkali solution are not specifically limited, as long as they can ensure the removal of the matrix phase while retaining the dispersed particle phase.

[0155] Furthermore, the method for removing the matrix phase in the alloy strip includes natural oxidation - pulverization and exfoliation removal of the matrix phase.

[0156] Furthermore, the particle size range of the high-purity target metal powder composed of the dispersed particle phase is 2 nm to 200 μm.

[0157] Furthermore, the shape of the high-purity target metal powder includes spherical, near-spherical, dendritic, rod-shaped, and plate-shaped.

[0158] Furthermore, the total content of H, O, N, S, P, F, Cl, I, and Br in the high-purity target metal powder is less than 2000 ppm.

[0159] The beneficial aspects of the above alternative technical features are further described in detail below:

[0160] First, the present invention can obtain nano-scale, sub-micron scale, and micron-scale dispersed particle phases by controlling the melt solidification rate respectively, and then obtain the target metal powder with corresponding particle size by removing the matrix phase, greatly reducing the preparation cost of ultra-fine metal powder.

[0161] Second, during the melt solidification process, the impurity elements in the melt are easily combined with the matrix phase and enriched in the matrix phase. Therefore, even if non-high-purity raw materials and ordinary crucibles are used, or other gas impurity elements enter the melt during the smelting process, dispersed particle phases and target metal powders with low impurity content can be obtained, which greatly reduces the production cost of high-purity powder materials.

[0162] Third, when M in the initial alloy A a M b or A a M b Al c is a combination of multiple elements, the obtained dispersed particle phase is also composed of multiple elements, which makes it more convenient and feasible to prepare the target alloy powder composed of the dispersed particle phase, greatly expanding the composition range and application field of the target alloy powder.

[0163] Finally, in the second step of the present invention, according to the characteristics that the matrix phase in the alloy strip is a low-melting-point and high-activity component, the matrix phase can be removed and the dispersed particle phase can be retained by at least one of the following three methods: 1) The matrix phase is removed by etching with an acid solution or an alkali solution while retaining the dispersed particle phase; 2) For the matrix phase that is extremely volatile, the matrix phase is removed by vacuum evaporation while retaining the dispersed particle phase; 3) For the matrix phase that is extremely prone to natural oxidation, such as the matrix phase mainly composed of rare earth elements, the matrix phase can also be made into powdered oxide powder by natural oxidation-pulverization of the matrix phase elements, and then the dispersed particle phase and the product after pulverization of the matrix phase are further separated to obtain the target metal powder.

[0164] Therefore, the preparation method of the present invention has the characteristics of simple process, easy operation and low cost, and can prepare various high-purity powder materials including nanoscale, sub-micron scale and micron scale, and has good application prospects in the fields of catalysis, powder metallurgy, composite materials, sterilization, metal injection molding, 3D printing, and other additive manufacturing fields. Detailed implementation manners

[0165] Hereinafter, the preparation method of the high-purity powder material will be further described through the following specific examples.

[0166] Example 1

[0167] This example provides a preparation method of nano CrV powder. The preparation method includes the following steps:

[0168] Select an alloy with an atomic ratio formula of Zn 54 Cr 23 V 23 According to the formula, weigh the raw materials. After melting and homogenizing the initial alloy raw materials, use the copper roller spinning technology to prepare an alloy strip with a thickness of 20 μm at a solidification rate of 10 6 K / s. The solidified structure of the alloy strip consists of a matrix phase with a composition of Zn and a large number of dispersed particle phases with a composition of Cr 54 Cr 23 V 23 The shape of the Cr 50 V 50 particles is nearly spherical, and the particle size ranges from 3 nm to 200 nm. The volume content of the Cr 50 V 50 particles in the alloy strip is about 42%; during the solidification process, impurity elements are enriched in the Zn matrix. 50 V 50 Remove the volatilized Zn in the alloy strip by vacuum heat treatment, so that the hardly volatile Cr

[0169] V 50 V 50 particles are separated, and nano Cr 50 V 50 powder is obtained, with a particle size ranging from 3 nm to 200 nm, and the total content of H, O, N, S, P, F, Cl, I, and Br in the nano Cr 50 V 50 powder is less than 1500 ppm.

[0170] Example 2

[0171] This example provides a preparation method of nano CrV powder. The preparation method includes the following steps:

[0172] The atomic ratio formula is selected as Zn 54 Cr 23 V 23 The raw materials are weighed according to the formula, and the initial alloy raw materials are melted uniformly and then the copper roller stripping technology is used to spin the raw materials at about 10 6 The solidification rate of K / s was 20 μm thick Zn 54 Cr 23 V 23 Alloy strip. The solidification structure of the alloy strip is composed of a matrix phase with Zn and a large amount of Cr. 50 V 50 The dispersed particle phase consists of Cr 50 V 50 The particle shape is nearly spherical, and the particle size ranges from 3nm to 200nm. 50 V 50 The volume content of particles in the alloy strip is about 42%; the impurity elements are enriched in the Zn matrix during solidification.

[0173] The Zn in the alloy strip is dissolved and removed by sodium hydroxide alkaline solution, so that the Cr in the alloy strip which is difficult to react with the alkaline solution 50 V 50 The particles are separated and nano-Cr is obtained. 50 V 50 Powder, the particle size range is 3nm ~ 200nm, and nano Cr 50 V 50 The total content of H, O, N, S, P, F, Cl, I and Br in the powder is less than 1500ppm.

[0174] Example 3

[0175] This embodiment provides a method for preparing nano-Ti powder, which comprises the following steps:

[0176] The atomic ratio formula is Ce 30 Ti 70 The raw materials are weighed according to the formula, and the initial alloy raw materials are melted uniformly and then the copper roller stripping technology is used to spin the raw materials at about 10 7 The solidification rate of K / s was used to prepare Ce with a thickness of 15 μm. 30 Ti 70 Alloy strip. The solidified structure of the alloy strip consists of a matrix phase with a component of Ce and a dispersed particle phase with a large component of Ti, wherein the shape of the Ti particles is nearly spherical and the particle size ranges from 3nm to 150nm. The volume content of Ti particles in the alloy strip is about 55%; during the solidification process, the impurity elements are enriched in the Ce matrix.

[0177] The Ce matrix in the alloy strip is dissolved and removed by hydrochloric acid solution, so that the Ti particles that are difficult to react with the acid solution in the alloy strip are separated out, namely nano-Ti powder is obtained. The particle size range of the nano-Ti powder is 3 nm to 150 nm, and the total content of H, O, N, S, P, F, Cl, I, and Br in the nano-Ti powder is less than 1500 ppm.

[0178] Example 4

[0179] This example provides a preparation method of nano-Ti-Zr-Hf-Nb-Ta powder. The preparation method includes the following steps:

[0180] Select an alloy with an atomic ratio formula of Ce 40 (Ti 20 Zr 20 Hf 20 Nb 20 Ta 20 ) 60 According to the formula, weigh the raw materials. After melting and homogenizing the initial alloy raw materials, use the copper roller spinning technology to prepare a Ce 7 (Ti 40 (Ti 20 Zr 20 Hf 20 Nb 20 Ta 20 ) 60 alloy strip with a thickness of 15 μm at a solidification rate of about 10 20 Zr 20 Hf 20 Nb 20 Ta 20 The solidification structure of the alloy strip consists of a matrix phase with a composition of Ce and a large number of dispersed particle phases with a composition of Ti 20 Zr 20 Hf 20 Nb 20 Ta 20 The shape of the particles is nearly spherical, and the particle size range is 3 nm to 150 nm. The volume content of Ti 20 Zr 20 Hf 20 Nb 20 Ta 20 particles in the alloy strip is about 50%; during the solidification process, impurity elements are enriched in the Ce matrix.

[0181] The Ce matrix in the alloy strip is dissolved and removed by hydrochloric acid solution, so that the Ti 20 Zr 20 Hf 20 Nb 20 Ta 20The particles are separated and nano-Ti is obtained. 20 Zr 20 Hf 20 Nb 20 Ta 20 Powder, the particle size range is 3nm ~ 150nm, and nano-Ti 20 Zr 20 Hf 20 Nb 20 Ta 20 The total content of H, O, N, S, P, F, Cl, I and Br in the powder is less than 1500ppm.

[0182] Example 5

[0183] This embodiment provides a method for preparing nano-submicron Ti-Nb powder, which comprises the following steps:

[0184] The atomic ratio formula is Ce 50 (Ti 50 Nb 50 ) 50 The raw materials are weighed according to the formula, and the initial alloy raw materials are melted uniformly and then the copper roller stripping technology is used to spin the raw materials at about 10 4 The solidification rate of K / s was 150 μm thick Ce 50 (Ti 50 Nb 50 ) 50 Alloy strip. The solidification structure of the alloy strip is composed of a matrix phase with a composition of Ce and a large amount of Ti 50 Nb 50 The dispersed particle phase consists of Ti 50 Nb 50 The particle shape is nearly spherical, and the particle size ranges from 50nm to 1μm. 50 Nb 50 The volume content of particles in the alloy strip is about 34%; the impurity elements are enriched in the Ce matrix during solidification.

[0185] The Ce matrix in the alloy strip is dissolved and removed by hydrochloric acid solution, so that the Ti in the alloy strip that is difficult to react with the acid solution is 50 Nb 50 The particles are separated, and nano-submicron Ti is obtained. 50 Nb 50 Powder, the particle size range is 50nm~1μm, and Ti 50 Nb 50 The total content of H, O, N, S, P, F, Cl, I and Br in the powder is less than 1500ppm.

[0186] Example 6

[0187] This embodiment provides a method for preparing micron-sized Ti-Co powder, and the preparation method includes the following steps:

[0188] Select an alloy with an atomic ratio formula of Gd 50 (Ti 50 Co 50 ) 50 According to the formula, weigh the raw materials. After melting and homogenizing the initial alloy raw materials, use the copper roller strip casting technology to prepare Gd 50 (Ti 50 Co 50 ) 50 alloy strips with a thickness of 3 mm at a solidification rate of about 150 K / s. The solidified structure of the alloy strip consists of a matrix phase with a composition of Gd and a large number of dispersed particle phases with a composition of Ti 50 Co 50 . Among them, the shape of the Ti 50 Co 50 particles is dendritic, and the particle size ranges from 1 μm to 100 μm. The volume content of Ti 50 Co 50 particles in the alloy strip is about 30%; during the solidification process, impurity elements are enriched in the Gd matrix.

[0189] Dissolve and remove the Gd matrix in the alloy strip through dilute hydrochloric acid solution, so that the Ti 50 Co 50 particles that are difficult to react with the dilute acid solution are separated out, and micron-sized Ti 50 Co 50 powder is obtained. Its particle size ranges from 1 μm to 100 μm, and the total content of H, O, N, S, P, F, Cl, I, and Br in the Ti 50 Co 50 powder is less than 1500 ppm.

[0190] Example 7

[0191] This embodiment provides a method for preparing submicron-micron Fe powder, and the preparation method includes the following steps:

[0192] Select an alloy with an atomic ratio formula of La 40 Fe 60 . According to the formula, weigh the raw materials. After melting and homogenizing the initial alloy raw materials, use the copper roller strip casting technology to prepare La 3 Fe 40 alloy strips with a thickness of 500 μm at a solidification rate of about 10 60Alloy strip. The solidification structure of the alloy strip consists of a matrix phase with a composition of La and a large number of dispersed particle phases with a composition of Fe. The shape of the Fe particles is nearly spherical, and the particle size ranges from 500 nm to 5 μm. The volume content of Fe particles in the alloy strip is about 32%; during the solidification process, impurity elements are enriched in the La matrix.

[0193] Convert La in the alloy through the natural oxidation-pulverization process of the La matrix in air 40 Fe 60 into lanthanum oxide, and then use the magnetic properties of Fe to separate the Fe particles from the lanthanum oxide, that is, obtain submicron-micron Fe powder with a particle size range of 500 nm to 5 μm, and the total content of H, O, N, S, P, F, Cl, I, and Br in the Fe powder is less than 1500 ppm.

[0194] Example 8

[0195] This example provides a method for preparing nano-Fe powder, and the preparation method includes the following steps:

[0196] Select an alloy with an atomic ratio formula of La 25 Fe 75 According to the formula, weigh the raw materials. After melting and homogenizing the initial alloy raw materials, use the copper roller spinning technology to prepare a La 6 Fe 25 alloy strip with a thickness of 20 μm at a solidification rate of about 10 75 K / s. The solidification structure of the alloy strip consists of a matrix phase with a composition of La and a large number of dispersed particle phases with a composition of Fe. The shape of the Fe particles is nearly spherical, and the particle size ranges from 3 nm to 200 nm. The volume content of Fe particles in the alloy strip is about 49%; during the solidification process, impurity elements are enriched in the La matrix.

[0197] Convert La in the La 25 Fe 75 alloy into lanthanum oxide through the natural oxidation-pulverization process of the La matrix in air, and then use the magnetic properties of Fe to separate the nano-Fe particles from the lanthanum oxide, that is, obtain nano-Fe powder with a particle size range of 3 nm to 200 nm, and the total content of H, O, N, S, P, F, Cl, I, and Br in the Fe powder is less than 1800 ppm.

[0198] Example 9

[0199] This example provides a method for preparing submicron-micron FeNi powder, and the preparation method includes the following steps:

[0200] Select an atomic ratio formula of Li 50 (Fe 50 Ni50 ) 50 The alloy, weigh the raw materials according to the formula. After melting and homogenizing the initial alloy raw materials, use the copper roller spinning technology to prepare an alloy strip with a thickness of 500 μm at a solidification rate of about 10 3 K / s. The solidified structure of the alloy strip consists of a matrix phase with a composition of Li and a large number of dispersed particle phases with a composition of Fe 50 (Fe 50 Ni 50 ) 50 The solidified structure of the alloy strip consists of a matrix phase with a composition of Li and a large number of dispersed particle phases with a composition of Fe 50 Ni 50 . The Fe 50 Ni 50 particles are nearly spherical or dendritic in shape, and the particle size ranges from 500 nm to 5 μm. The Fe 50 Ni 50 particles have a volume content of about 34% in the alloy strip; during the solidification process, impurity elements are enriched in the Li matrix.

[0201] Through the natural oxidation-pulverization process of the Li matrix in the air, the Li in the Li 50 (Fe 50 Ni 50 ) 50 alloy is converted into oxide powder, and then use the magnetic properties of Fe 50 Ni 50 to separate the Fe 50 Ni 50 particles from the oxidation product of Li, that is, obtain submicron-micron Fe 50 Ni 50 powder, the particle size of which ranges from 500 nm to 5 μm, and the total content of H, O, N, S, P, F, Cl, I, Br in the Fe 50 Ni 50 powder is less than 1800 ppm.

[0202] Example 10

[0203] This example provides a method for preparing nano-Ti-Al-V powder, and the preparation method includes the following steps:

[0204] Select an alloy with an atomic ratio formula of Ce 30 Al 12 (Ti 96 V4) 58 The alloy, weigh the raw materials according to the formula. After melting and homogenizing the initial alloy raw materials, use the copper roller spinning technology to prepare a Ce 6 K / s. The solidified structure of the alloy strip consists of a matrix phase with a composition of Li and a large number of dispersed particle phases with a composition of Fe 30 Al 12 (Ti 96 V4) alloy strip with a thickness of 20 μm at a solidification rate of about 1058 Alloy strip. The solidification structure of the alloy strip consists of a matrix phase with a composition of Ce 85 Al 15 and a large number of dispersed particle phases with a composition of (Ti 96 V4) 90 Al 10 . Among them, the (Ti 96 V4) 90 Al 10 particles are nearly spherical in shape, and the particle size ranges from 3 nm to 200 nm. The (Ti 96 V4) 90 Al 10 particles have a volume content of approximately 52% in the alloy strip; during the solidification process, impurity elements are enriched in the Ce 85 Al 15 matrix.

[0205] The Ce 30 Al 12 (Ti 96 V4) 58 in the alloy strip is removed by reacting with a dilute hydrochloric acid solution, so that the (Ti 85 Al 15 matrix phase that is difficult to react with the dilute hydrochloric acid solution is removed, and the (Ti 96 V4) 90 Al 10 particles are separated out, and nano (Ti 96 V4) 90 Al 10 powder is obtained. The particle size of the nano (Ti 96 V4) 90 Al 10 powder ranges from 3 nm to 200 nm, and the total content of H, O, N, S, P, F, Cl, I, and Br in the nano (Ti

[0206] Example 11

[0207] This example provides a method for preparing submicron-micron Ti-Al-V powder. The preparation method includes the following steps:

[0208] Select an alloy with an atomic ratio formula of Ce 30 Al 12 (Ti 96 V4) 58 . Weigh the raw materials according to the formula. After melting and homogenizing the initial alloy raw materials, use the copper roller spinning technology to prepare a Ce 3 with a thickness of about 500 μm at a solidification rate of about 10 30 Al 12 (Ti 96 V4)58 Alloy strip. The solidified structure of the alloy strip consists of a matrix phase with a composition of Ce 85 Al 15 and a large number of dispersed particle phases with a composition of (Ti 96 V4) 90 Al 10 . Among them, the (Ti 96 V4) 90 Al 10 particles are nearly spherical or dendritic in shape, and the particle size ranges from 500 nm to 5 μm. The (Ti 96 V4) 90 Al 10 particles have a volume content of about 52% in the alloy strip; during the solidification process, impurity elements are enriched in the Ce 85 Al 15 matrix.

[0209] The Ce 30 Al 12 (Ti 96 V4) 58 in the alloy strip is removed by reacting with a dilute hydrochloric acid solution, so that the (Ti 85 Al 15 matrix phase that is difficult to react with the dilute hydrochloric acid solution reacts, and the (Ti 96 V4) 90 Al 10 particles are separated, and sub-micron to micron (Ti 96 V4) 90 Al 10 powder is obtained. The particle size of the powder ranges from 500 nm to 5 μm, and the total content of H, O, N, S, P, F, Cl, I, and Br in the nano (Ti 96 V4) 90 Al 10 powder is less than 1400 ppm.

[0210] Example 12

[0211] This example provides a method for preparing nano-Ti powder. The preparation method includes the following steps:

[0212] Select sponge Ti and rare earth Ce raw materials with the atomic percentage contents of T (including O, H, N, P, S, F, Cl, Br, I) impurity elements being 3 at.% and 2.5 at.% respectively. According to the molar ratio of Ce to Ti being about 1:1, the sponge Ti and rare earth Ce are fully melted to obtain a uniform initial alloy melt with the main atomic percentage composition of Ce 47.25 Ti 47.25 T 2.5 .

[0213] Using the copper roller melt spinning technique, an initial alloy melt is prepared into a Ce 6 Ti 47.25 Ti 47.25 T 2.5 alloy strip with a thickness of 15 μm at a solidification rate of about 10 95.2 T 4.8 matrix phase with a main component of Ce 99.8 T 0.2 and a large number of dispersed particle phases with a main component of Ti 99.8 T 0.2 The shape of the Ti 99.8 T 0.2 dispersed particles is nearly spherical, and the particle size ranges from 3 nm to 150 nm. The volume content of the Ti

[0214] Ce 47.25 Ti 47.25 T 2.5 alloy strip obtained is an alloy strip composed of endogenic powder and a coating.

[0215] By using a dilute acid solution to remove the Ce 95.2 T 4.8 matrix in the alloy strip, the Ti 99.8 T 0.2 particles that are difficult to react with the dilute acid solution in the alloy strip are separated out, and Ti 99.8 T 0.2 nanopowder is obtained. The particle size ranges from 3 nm to 150 nm, and the total content of O, H, N, P, S, F, Cl, Br, and I it contains is 0.2 at.%.

[0216] Under a protective atmosphere, the nanopowder mainly composed of Ti 99.8 T 0.2 is mixed with epoxy resin and other coating components to prepare a nano-Ti modified polymer anticorrosive coating.

[0217] Example 13

[0218] This example provides a method for preparing micron dendritic Ti-Nb powder, and this preparation method includes the following steps:

[0219] Sponge Ti, Nb sheets, and rare earth Gd raw materials with atomic percentage contents of impurity elements T (including O, H, N, P, S, F, Cl, Br, I) of 3 at.%, 1 at.%, and 2.5 at.% respectively are selected. According to the molar ratio of Gd:Ti:Nb of about 2:1:1, the alloy raw materials are melted to obtain an alloy with an atomic percentage composition mainly of Gd 48.75 Ti 24.5 Nb24.5 T 2.25 Uniform initial alloy melt.

[0220] The initial alloy melt was prepared into Gd alloy strips with a thickness of about 300 μm at a solidification rate of about 10 3 K / s by the copper roller melt spinning technique. 48.75 Ti 24.5 Nb 24.5 T 2.25 The solidified structure of the alloy strip consists of a matrix phase with an atomic percentage composition mainly of Gd 95.9 T 4.1 and a large number of dispersed particle phases with a composition mainly of Ti 49.85 Nb 49.85 T 0.3 The shape of the Ti 49.85 Nb 49.85 T 0.3 dispersed particles is dendritic, and their particle size ranges from 1 μm to 50 μm. The volume percentage content of the Ti 49.85 Nb 49.85 T 0.3 dispersed particles in the alloy strip is about 35%;

[0221] The Gd 95.9 T 4.1 matrix phase in the alloy strip was removed by a dilute acid solution, so that the Ti 49.85 Nb 49.85 T 0.3 dispersed particles that are difficult to react with the dilute acid solution are separated out, and micro-powder mainly composed of Ti 49.85 Nb 49.85 T 0.3 is obtained. Its particle size ranges from 1 μm to 50 μm, and the total content of O, H, N, P, S, F, Cl, Br, and I it contains is 0.3 at.%.

[0222] The above-mentioned Ti 49.85 Nb 49.85 T 0.3 alloy powder was sieved through 1000-mesh and 2000-mesh sieves to obtain classified Ti 49.85 Nb 49.85 T 0.3 alloy powders with particle size ranges of 53 μm - 13 μm and 13 μm - 6.5 μm respectively. They were respectively subjected to plasma spheroidization treatment to further obtain Ti-Nb-T alloy powders with particle size ranges of 53 μm - 13 μm and 13 μm - 6.5 μm and shapes close to spherical. The obtained spherical Ti-Nb-T alloy powders can be used in the fields of 3D metal printing, metal injection molding, and powder metallurgy.

[0223] Example 14

[0224] This example provides a method for preparing nano-TiNi powder, and the preparation method includes the following steps:

[0225] Select Ti raw materials, Ni sheets, and rare earth Gd raw materials with the atomic percentage contents of impurity elements T (including O, H, N, P, S, F, Cl, Br, I) being 1 at.%, 0.5 at.%, and 2.5 at.% respectively. Melt the initial raw materials according to the molar ratio of Gd:Ti:Ni being approximately 2:1:1 to obtain a homogeneous initial alloy melt with the atomic percentage composition mainly being Gd 48.8 Ti 25.25 Ni 25.25 T 1.7 of.

[0226] Prepare the initial alloy melt into a Gd 6 Ti 48.8 Ti 25.25 Ni 25.25 T 1.7 alloy strip with a thickness of approximately 15 μm at a solidification rate of approximately ~10 96.8 T 3.2 The solidification structure of the alloy strip consists of a matrix phase mainly composed of Gd 49.9 Ni 49.9 T 0.2 and a large number of dispersed particle phases mainly composed of Ti 49.9 Ni 49.9 T 0.2 (which is a TiNi intermetallic compound). The shape of the Ti 49.9 Ni 49.9 T 0.2 dispersed particles is nearly spherical, and the particle size ranges from 3 nm to 150 nm. The volume content of the Ti

[0227] Remove the Gd 96.8 T 3.2 matrix in the alloy strip through a dilute acid solution, so that the Ti 99.8 T 0.2 particles that are difficult to react with the dilute acid solution in the alloy strip are separated out, that is, Ti 49.9 Ni 49.9 T 0.2 nano powder is obtained, whose particle size ranges from 3 nm to 150 nm, and the total content of O, H, N, P, S, F, Cl, Br, I contained therein is 0.2 at.%.

[0228] Example 15

[0229] This embodiment provides a method for preparing submicron-micron Fe powder, and the preparation method includes the following steps:

[0230] Select Fe sheets and rare earth La raw materials with the atomic percentage contents of impurity elements T (including O, H, N, P, S, F, Cl, Br, I) being 1 at.% and 2.5 at.% respectively. Melt each alloy raw material according to the molar ratio of La:Fe being about 1:2 to obtain a uniform initial alloy melt with the atomic percentage composition mainly being La 32.8 Fe 65.7 T 1.5 of.

[0231] Prepare the initial alloy melt into La 4 Fe 32.8 Fe 65.7 T 1.5 alloy strips with a thickness of about 100 μm at a solidification rate of about 10 95.9 T 4.1 K / s by means of copper roller strip casting technology. The solidified structure of the alloy strip consists of a matrix phase with the atomic percentage composition mainly being La 99.85 T 0.15 and a large number of dispersed particle phases with the composition mainly being Fe 99.85 T 0.15 . The shape of the Fe 99.85 T 0.15 dispersed particles is nearly spherical or dendritic, and the particle size range is 500 nm - 3 μm. The volume percentage content of the Fe

[0232] T 95.9 T 4.1 dispersed particles in the alloy strip is about 36%; 99.85 T 0.15 Remove the La 99.85 T 0.15 matrix phase in the alloy strip through a dilute acid solution, and at the same time, use the magnetism of Fe to quickly separate the separated Fe

[0233] Example 16

[0234] This embodiment provides a method for preparing nano-Ti-V-Al alloy powder, and the preparation method includes the following steps:

[0235] Select sponge Ti, V blocks, rare earth Ce, and Al raw materials with the atomic percentage contents of impurities T (including O, H, N, P, S, F, Cl) being 1 at.%, 1 at.%, 2.5 at.%, and 0.2 at.% respectively. Melt the initial alloy raw materials in a certain proportion to obtain an initial alloy melt with the atomic percentage composition mainly of Ce 40.2 (Ti 96 V4) 37.9 Al 20.5 T 1.4 of the initial alloy melt.

[0236] Prepare the initial alloy melt into a Ce 6 (Ti 40.2 (Ti 96 V4) 37.9 Al 20.5 T 1.4 alloy strip with a thickness of about 20 μm at a solidification rate of about 10 73.2 Al 24.3 T 2.5 K / s by means of the copper roller melt spinning technique. The solidified structure of the alloy strip consists of a matrix phase with an average composition mainly of Ce 96 Al 84 Al 15.8 T 0.2 and a large number of dispersed particle phases with a composition mainly of (Ti 96 V4) 84 Al 15.8 T 0.2 where the shape of the (Ti 96 V4) 84 Al 15.8 T 0.2 dispersed particles is nearly spherical, and the particle size ranges from 5 nm to 200 nm. The volume content of the (Ti

[0237] in the alloy strip is about 33%; 73.2 Al 24.3 T 2.5 Remove the Ce 96 V4) 84 Al 15.8 T 0.2 matrix in the alloy strip with a dilute acid solution, so that the (Ti 96 V4) 84 Al 15.8 T 0.2 particles that are difficult to react with the dilute acid solution are separated out, and thus (Ti

[0238] nanopowder is obtained, with a particle size ranging from 5 nm to 200 nm and the total content of O, H, N, P, S, F, Cl, Br, and I being 0.2 at.%.Under a protective atmosphere, nano-powders mainly composed of (Ti 96 V4) 84 Al 15.8 T 0.2 are mixed with epoxy resin and other coating components to prepare a nano-Ti alloy modified polymer anti-corrosion coating.

[0239] Example 17

[0240] This example provides a method for preparing nano-Ti-Al alloy powder, which includes the following steps:

[0241] Select sponge Ti, rare earth Ce, and Al raw materials with the atomic percentage contents of impurity elements T (including at least one of O, H, N, P, S, F, and Cl) being 3 at.%, 2.5 at.%, and 0.2 at.%, respectively. Among them, sponge Ti also contains 0.5 at.% of Mn; rare earth Ce also contains 0.7 at.% of Mg.

[0242] The initial alloy raw materials are fully melted according to a certain ratio to obtain an initial alloy melt with the atomic percentage composition mainly being (Ce 99.3 Mg 0.7 ) 40 (Ti 99.5 Mn 0.5 ) 38 Al 20.6 T 1.4 .

[0243] The initial alloy melt is prepared into an alloy strip with a thickness of about ~20 μm at a solidification rate of about ~10 6 K / s by the copper roller strip casting technique. The solidified structure of this alloy strip consists of a matrix phase with an average composition mainly being (Ce 99.3 Mg 0.7 ) 40 (Ti 99.5 Mn 0.5 ) 38 Al 20.6 T 1.4 and a large number of dispersed particle phases with a composition mainly being (Ti 99.3 Mg 0.7 )Al 24.3 T 2.5 . Among them, (Ti 99.5 Mn 0.5 ) 84 Al 15.8 T 0.2 99.5 Mn 0.5 ) 84 Al 15.8 T 0.2The shape of the dispersed particles is nearly spherical, and the particle size ranges from 5 nm to 200 nm. (Ti 99.5 Mn 0.5 ) 84 Al 15.8 T 0.2 The volume content of the dispersed particles in the alloy strip is about 33%; moreover, the introduction of Mn and Mg into the alloy melt does not result in the formation of intermetallic compounds composed of Ce, Mg, Ti, and Mn in the initial alloy strip; and it does not affect the structural characteristics of the matrix phase and the dispersed particle phase in the alloy strip, nor does it affect the law of the reduction of impurity content in the dispersed particle phase.

[0244] The (Ce 99.3 Mg 0.7 )Al 24.3 T 2.5 matrix in the alloy strip is removed by a dilute acid solution, so that the (Ti 99.5 Mn 0.5 ) 84 Al 15.8 T 0.2 particles that are difficult to react with the dilute acid solution in the alloy strip are separated out, and thus nanometer powder mainly composed of (Ti 99.5 Mn 0.5 ) 84 Al 15.8 T 0.2 is obtained. Its particle size ranges from 5 nm to 200 nm, and the total content of O, H, N, P, S, F, Cl, Br, and I it contains is 0.2 at.%.

[0245] Under a protective atmosphere, the nanometer powder mainly composed of (Ti 99.5 Mn 0.5 ) 84 Al 15.8 T 0.2 is mixed with epoxy resin and other coating components to prepare a nanometer Ti alloy modified polymer anticorrosive coating.

[0246] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0247] The above-described embodiments merely represent several implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all fall within the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims.

Claims

1. A method for preparing a high-purity powder material, characterized in that, It includes the following steps: Step S1, select the initial alloy raw materials, melt the initial alloy raw materials according to the initial alloy composition ratio to obtain a uniform initial alloy melt containing impurity element T, where T includes at least one of O, H, N, P, S, F, Cl, I, Br, and the average composition of the initial alloy melt includes any one of the following combinations: Composition (1): The average composition of the initial alloy melt is mainly A a (M x D y ) b T d , where A contains at least one of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu; M contains at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti; D contains at least one of Fe, Co, Ni, where x, y; a, b, d represent the atomic percentage contents of the corresponding constituent elements, and 24.9% ≤ a ≤ 99.4%, 0.5% ≤ b ≤ 75%, 0 < d ≤ 10%; 10% ≤ x ≤ 55%, 45% ≤ y ≤ 90%; Combination (2): The average composition of the initial alloy melt is mainly A a M b T d , where A contains at least one of Mg, Ca, Li, Na, K, Cu, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu; M contains at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti; where a, b, d represent the atomic percentage contents of the corresponding constituent elements, and 24.9% ≤ a ≤ 99.4%, 0.5% ≤ b ≤ 75%, 0 < d ≤ 10%; Combination (3): The average composition of the initial alloy melt is mainly A a M b T d , where A contains at least one of Zn, Mg, Sn, Pb, Ga, In, Al, La, Ge, Cu, K, Na, Li, M contains at least one of B, Bi, Fe, Ni, Cu, Ag, Si, Ge, Cr, V, where a, b, d represent the atomic percentage contents of the corresponding constituent elements, and 24.9% ≤ a ≤ 59.9%, 40% < b ≤ 75%, 0 < d ≤ 10%; Combination (4): When the average composition of the initial alloy melt is mainly A a M b Al c T d wherein, A contains at least one of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu; M contains at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti; Al is aluminum; a, b, c, and d respectively represent the atomic percentage contents of the corresponding constituent elements, and 29.8% ≤ a ≤ 64.8%, 35% < b ≤ 70%, 0.1% ≤ c ≤ 25%, 0 < d ≤ 10%; Step S2, solidify the initial alloy melt into an initial alloy strip; the solidification structure of the initial alloy strip includes a matrix phase and a dispersed particle phase; the melting point of the matrix phase is lower than that of the dispersed particle phase, and the dispersed particle phase is coated in the matrix phase; during the solidification process of the initial alloy melt, the impurity element T in the initial alloy melt is redistributed between the dispersed particle phase and the matrix phase and enriched in the matrix phase, thereby purifying the dispersed particle phase; When the average composition of the initial alloy melt is the combination (1) in step S1, the composition of the dispersed particle phase in the initial alloy strip is mainly (M x D y ) x1 T z1 , and the average composition of the matrix phase is mainly A x2 T z2 ; and 98.5% ≤ x1 < 100%, 0 < z1 ≤ 1.5%; 80% ≤ x2 < 100%, 0 < z2 ≤ 20%; z1 < d < z2, 2z1 < z2; x1, z1, x2, z2 respectively represent the atomic percentage contents of the corresponding constituent elements; When the average composition of the initial alloy melt is the combination (2) or the combination (3) in step S1, the composition of the dispersed particle phase in the initial alloy strip is mainly M x1 T z1 , and the average composition of the matrix phase is mainly A x2 T z2 ; and 98.5% ≤ x1 < 100%, 0 < z1 ≤ 1.5%; 80% ≤ x2 < 100%, 0 < z2 ≤ 20%; z1 < d < z2, 2z1 < z2; x1, z1, x2, z2 respectively represent the atomic percentage contents of the corresponding constituent elements; When the average composition of the initial alloy melt is the combination (4) in step S1, the composition of the dispersed particle phase in the initial alloy strip is mainly M x1 Al y1 T z1 , and the average composition of the matrix phase is mainly A x2 Al y2 T z2 ; and 77.8% ≤ x1 ≤ 99.8%, 0.1% ≤ y1 ≤ 22%, 0 < z1 ≤ 1.5%; 69.8% ≤ x2 ≤ 99.7%, 0.2% ≤ y2 ≤ 30%, 0 < z2 ≤ 20%, z1 < d < z2, 2z1 < z2, y1 < y2, x1, y1, z1, x2, y2, z2 respectively represent the atomic percentage contents of the corresponding constituent elements; Step S3, remove the matrix phase in the initial alloy strip and retain the dispersed particle phase that cannot be removed simultaneously during the removal of the matrix phase, and collect the exfoliated dispersed particle phase, thus obtaining a high-purity target powder material composed of the original dispersed particles.

2. The preparation method of the high-purity powder material according to claim 1, characterized in that, The sources of the T impurity elements in the initial alloy melt include: impurities introduced by the initial alloy raw materials, and impurities introduced by the atmosphere or crucible during the smelting process.

3. The preparation method of the high-purity powder material according to claim 1, characterized in that, The initial alloy strip does not contain intermetallic compounds composed of A and M.

4. The preparation method of the high-purity powder material according to claim 1, characterized in that The proportion of the number of single crystal particles of the dispersed particles in the initial alloy strip in all the dispersed particle numbers is not less than 60%.

5. The preparation method of the high-purity powder material according to claim 1, characterized in that The particles of the dispersed particle phase include at least one of dendritic, spherical, near-spherical, square, cake-shaped, and rod-shaped; and When the particle shape is rod-shaped, the size of the particle specifically refers to the diameter size of the rod cross-section.

6. The preparation method of the high-purity powder material according to claim 1, characterized in that, The methods for removing the matrix phase in the alloy strip include at least one of acid reaction removal, alkali reaction removal, vacuum volatilization removal, and matrix phase natural oxidation - pulverization and exfoliation removal.

7. The preparation method of the high-purity powder material according to claim 1, characterized in that, The particle size range of the high-purity powder material is 2 nm to 3 mm.

8. The preparation method of the high-purity powder material according to claim 1, characterized in that, After the step S3, the following steps are further carried out: after screening the high-purity powder material, the high-purity powder material with a particle size range of 5 μm to 200 μm is selected for plasma spheroidization treatment to obtain a spherical high-purity powder material.

9. Application of the high-purity powder material according to any one of claims 1-8 in a catalytic material.

10. Application of the high-purity powder material according to any one of claims 1-8 in powder metallurgy.

11. Application of the high-purity powder material according to any one of claims 1-8 in a composite material.

12. Application of the high-purity powder material according to any one of claims 1-8 in an absorbing material.

13. Application of the high-purity powder material according to any one of claims 1-8 in a bactericidal material.

14. Application of the high-purity powder material according to any one of claims 1-8 in a magnetic material.

15. Application of the high-purity powder material according to any one of claims 1-8 in metal injection molding.

16. Application of the high-purity powder material according to any one of claims 1-8 in 3D printing.

17. Application of the high-purity powder material according to any one of claims 1-8 in a coating.

18. An alloy strip, characterized in that, It includes an endogenic powder and a coating; the solidification structure of the alloy strip includes a matrix phase and a dispersed particle phase, the matrix phase is the coating, and the dispersed particle phase is the endogenic powder; the melting point of the coating is lower than the melting point of the endogenic powder, and the endogenic powder is coated in the coating; The chemical composition and structure of the alloy strip include any one of the following four combinations: 1) The composition of the internal powder in the alloy strip is mainly (M x D y ), x1 T z1 , and the average composition of the coating is mainly A x2 T z2 ; and 98.5% ≤ x1 < 100%, 0 < z1 ≤ 1.5%; 80% ≤ x2 < 100%, 0 < z2 ≤ 20%; z1 < d < z2, 2z1 < z2; x1, z1, x2, z2 respectively represent the atomic percentage contents of the corresponding constituent elements; where A contains at least one of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, M contains at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti, D contains at least one of Fe, Co, Ni; T contains at least one of O, H, N, P, S, F, Cl, I, Br; x, y represent the atomic percentage contents of the corresponding constituent elements, 10% ≤ x ≤ 55%, 45% ≤ y ≤ 90%; 2) The composition of the in-situ powder in the alloy strip is mainly M x1 T z1 , and the average composition of the coating is mainly A x2 T z2 ; and 98.5% ≤ x1 < 100%, 0 < z1 ≤ 1.5%; 80% ≤ x2 < 100%, 0 < z2 ≤ 20%; z1 < d < z2, 2z1 < z2; x1, z1, x2, z2 respectively represent the atomic percentage content of the corresponding constituent elements; wherein, A contains at least one of Mg, Ca, Li, Na, K, Cu, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, M contains at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti; T contains at least one of O, H, N, P, S, F, Cl, I, Br; 3) The composition of the internal powder in the alloy strip is mainly M x1 T z1 , and the average composition of the coating is mainly A x2 T z2 ; and 98.5% ≤ x1 < 100%, 0 < z1 ≤ 1.5%; 80% ≤ x2 < 100%, 0 < z2 ≤ 20%; z1 < d < z2, 2z1 < z2; x1, z1, x2, z2 respectively represent the atomic percentage contents of the corresponding constituent elements; where A includes at least one of Zn, Mg, Sn, Pb, Ga, In, Al, La, Ge, Cu, K, Na, Li, M includes at least one of B, Bi, Fe, Ni, Cu, Ag, Si, Ge, Cr, V; T includes at least one of O, H, N, P, S, F, Cl, I, Br; 4) The composition of the internal powder in the alloy strip is mainly M x1 Al y1 T z1 , and the average composition of the coating is mainly A x2 Al y2 T z2 ; and 77.8% ≤ x1 ≤ 99.8%, 0.1% ≤ y1 ≤ 22%, 0 < z1 ≤ 1.5%; 69.8% ≤ x2 ≤ 99.7%, 0.2% ≤ y2 ≤ 30%, 0 < z2 ≤ 20%, z1 < d < z2, 2z1 < z2, y1 < y2, where x1, y1, z1, x2, y2, z2 represent the atomic percentage contents of the corresponding constituent elements; wherein, A contains at least one of Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu; M contains at least one of W, Cr, Mo, V, Ta, Nb, Zr, Hf, Ti; Al is aluminum; T contains at least one of O, H, N, P, S, F, Cl, I, Br.

19. An alloy strip according to claim 18, characterized in that, The shape of the endogenic powder includes at least one of dendritic, spherical, near-spherical, square, cake-shaped, and rod-shaped.