阅读说明：本技术 一种Mo-Tb-Dy合金材料及其制备方法 (Mo-Tb-Dy alloy material and preparation method thereof ) 是由 姚茂海 王选理 罗天纵 吕晶 李�杰 张晓梅 杨瑞芳 于 2019-12-17 设计创作，主要内容包括：本发明公开了一种Mo-Tb-Dy合金材料,包括重量比为85.4-87.4：9～10：3.6～4.6的Mo、Tb和Dy,800℃时,Mo-Tb-Dy合金的抗拉强度Rm可达到173.3Mpa,本发明还公开了其制备方法,其包括以下步骤：通入惰性气体保护,将Mo、Tb、Dy三种金属粉末混合,进行球磨混料；将经球磨混料的Mo-RE粉末,进行装料填实,利用冷等静压工艺进行粉末预成型；将预成型的材料真空高温烧结。本发明制备的Mo-Tb-Dy合金材料,由于Tb、Dy稀土元素的加入,Mo-Tb-Dy合金材料的高温性能显著提高,在800℃时,Mo-Tb-Dy合金材料的抗拉强度Rm可达到173.3MPa。(The invention discloses a Mo-Tb-Dy alloy material, which comprises the following components in parts by weight of 85.4-87.4: 9-10: 3.6-4.6 of Mo, Tb and Dy, wherein the tensile strength Rm of the Mo-Tb-Dy alloy can reach 173.3Mpa at 800 ℃, and the invention also discloses a preparation method of the Mo-Tb-Dy alloy, which comprises the following steps: introducing inert gas for protection, mixing three metal powders of Mo, Tb and Dy, and carrying out ball milling and mixing; carrying out charging and filling on the Mo-RE powder subjected to ball milling and mixing, and carrying out powder preforming by utilizing a cold isostatic pressing process; and (4) sintering the preformed material in vacuum at high temperature. According to the Mo-Tb-Dy alloy material prepared by the invention, due to the addition of Tb and Dy rare earth elements, the high-temperature performance of the Mo-Tb-Dy alloy material is obviously improved, and the tensile strength Rm of the Mo-Tb-Dy alloy material can reach 173.3MPa at 800 ℃.)

1. The Mo-Tb-Dy alloy material is characterized by comprising the following components in a weight ratio of 85.4-87.4: 9-10: 3.6 to 4.6 of Mo, Tb and Dy, wherein the tensile strength Rm of the Mo-Tb-Dy alloy is not lower than 173.3MPa at 800 ℃.

2. A method for preparing the Mo-Tb-Dy alloy material according to claim 1, characterized by comprising the steps of:

introducing inert gas for protection, mixing three metal powders of Mo, Tb and Dy according to a weight ratio, and carrying out ball milling and mixing, wherein the ball milling time is 4-12 h, and the rotating speed of the ball mill is 200-500 r/min;

under the protection of inert gas, filling the ball-milled and mixed Mo-Tb-Dy powder into a silica gel tube, filling and compacting, fixing and straightening the outside of the silica gel tube, and performing powder material preforming by using a cold isostatic pressing process;

and (3) sintering the preformed material in vacuum, wherein the sintering temperature is 1100-1900 ℃, the sintering time is 8-16 h, and the vacuum degree is less than 133 Pa.

3. The method of preparing a Mo-Tb-Dy alloy material according to claim 2, wherein: the outer part of the silicone tube is fixedly straightened in a mode that the arc tube piece is fixed to the outer part of the silicone tube through the elastic piece.

4. The method of preparing a Mo-Tb-Dy alloy material according to claim 2, wherein: the parameters of the cold isostatic pressing process are that the pressure is more than or equal to 180MPa and less than 200MPa, and the pressure maintaining time is 3-6 min.

5. The method of producing a Mo-Tb-Dy alloy material according to any one of claims 2 to 4, wherein: and transversely placing the preformed material into heating equipment, coating alumina powder on the outer side of the preformed material, and sintering at high temperature in vacuum.

6. The method of producing a Mo-Tb-Dy alloy material according to any one of claims 2 to 4, wherein: the Ferris particle size of the Mo metal powder is 2.14 mu m, the purity is 99.95% -99.99%, the average Ferris particle size of the Tb metal powder and the Dy metal powder is 2.00 mu m, and the purity is 99.95% -99.99%.

Technical Field

The invention relates to the field of alloy material preparation, in particular to a Mo-Tb-Dy alloy material and a preparation method thereof.

Background

The molybdenum alloy has good high-temperature performance as a high-temperature alloy, and is widely applied to the industrial fields of machinery, electronics and the like. In the field of nuclear industry, molybdenum alloys are often used as structural materials in nuclear facilities due to their good compatibility with nuclear materials. At room temperature, the molybdenum alloy has poor high and low temperature brittleness transition temperature (DBTT), and is easy to oxidize at high temperature, so that the extension of the application field of the molybdenum alloy is limited.

The existing molybdenum alloys mainly comprise the following components: single crystal molybdenum alloy, molybdenum-rhenium alloy (Mo-Re), molybdenum-titanium-zirconium (MTZ), molybdenum-silicon alloy (Mo-Si), molybdenum rare earth oxide (Mo-REO) and the like, wherein the material properties of each molybdenum alloy are different, and the molybdenum alloy is suitable for different fields. The main problems of the existing molybdenum alloy are as follows: the room temperature brittleness and the high temperature oxidation of the molybdenum alloy. The literature reports that a certain amount of Rare Earth (RE) and Rare Earth Oxide (REO) are added into molybdenum, the recrystallization temperature of the molybdenum can be increased by about 500 ℃, and the rare earth oxide obviously improves the room-temperature tensile strength and the high-temperature performance of the molybdenum. Rare earth oxide is added into molybdenum alloy, and the molybdenum rare earth oxide (Mo-REO) is mainly prepared by a solid-liquid doping mode, a sol-gel doping mode, a sol-spray drying technology and the like.

A method for manufacturing a molybdenum alloy material used for a nuclear fusion device (application number: 201210307083.X) provides a method for preparing a 0.40-0.55 Ti-0.06-0.12 Zr-0.01-0.04C-Mo alloy material by using a powder metallurgy method. The molybdenum alloy material in the patent has poor high-temperature performance, and the rubber tube is adopted for filling and compacting during the cold isostatic pressing process, so that the densification degree of the molybdenum alloy material needs to be improved, and the problem that the size of the molybdenum alloy rod cannot be accurately controlled exists. The application numbers are: 200710034999.1, 20051002080.2, 200610043762.5 and 200610098707.6, the molybdenum rare earth alloy is prepared by different methods such as liquid-liquid doping, solid-liquid doping and solid-solid doping, but no relevant report is found on the preparation technology of molybdenum terbium dysprosium (Mo-Tb-Dy) molybdenum rare earth ternary alloy rods.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the problems in the prior art are solved, the Mo-Tb-Dy alloy material and the preparation method thereof are provided, and the high-temperature performance of the molybdenum alloy material is improved.

The technical scheme adopted by the invention is as follows:

a Mo-Tb-Dy alloy material comprises 85.4-87.4 by weight: 9-10: 3.6 to 4.6 of Mo, Tb and Dy, wherein the tensile strength Rm of the Mo-Tb-Dy alloy is not lower than 173.3Mpa at 800 ℃.

The invention also discloses a preparation method of the Mo-Tb-Dy alloy material, which comprises the following steps:

introducing inert gas for protection, mixing three metal powders of Mo, Tb and Dy, and carrying out ball milling and mixing for 4-12 h, wherein the rotating speed of the ball mill is 200-500 r/min;

under the protection of inert gas, filling the ball-milled and mixed Mo-Tb-Dy powder into a silica gel tube, filling and compacting, fixing and straightening the outside of the silica gel tube, and performing powder material preforming by using a cold isostatic pressing process;

and (3) sintering the preformed material in vacuum, wherein the sintering temperature is 1100-1900 ℃, the sintering time is 8-16 h, and the vacuum degree is less than 133 Pa.

Preferably, the mode of fixing and straightening the outside of the silicone tube is to fix the arc-shaped duct piece outside the silicone tube through an elastic piece.

Preferably, the parameters of the cold isostatic pressing process are that the pressure is more than or equal to 180MPa and less than 200MPa, and the pressure maintaining time is 3-6 min.

Preferably, the preformed material is horizontally placed into a heating device, aluminum oxide powder is coated on the outer side of the preformed material, and vacuum high-temperature sintering is carried out.

Preferably, the Freund granularity of the Mo metal powder is 2.14 μm, the purity is 99.95-99.99%, the average Freund granularity of the Tb metal powder and the Dy metal powder is 2.00 μm, and the purity is 99.95-99.99%.

Compared with the prior art, the invention has the following advantages:

(1) according to the Mo-Tb-Dy alloy material prepared by the invention, due to the addition of Tb and Dy rare earth elements, Mo and the rare earth elements Tb and Dy generate intermetallic compounds, and the intermetallic compounds have the characteristics of high melting point, high stability and the like, and pin crystal boundaries at high temperature, inhibit crystal boundary movement and further obviously improve the high-temperature performance of the alloy. At 800 ℃, the tensile strength Rm of the Mo-Tb-Dy alloy material can reach 173.3MPa, and the Mo-Tb-Dy alloy material has obvious advantages compared with the existing Mo-Tb-Dy alloy material.

(2) The invention adopts a powder metallurgy method to prepare the Mo-Tb-Dy alloy material: after the powder is preformed by cold isostatic pressing, vacuum high-temperature sintering is carried out, so that the densification of the material is facilitated, and the rare earth in the alloy is uniformly distributed. The whole process from mixing to preforming is carried out under the protection of inert gas, so that the impurity content in the alloy is prevented from rising due to the reaction of Tb and Dy rare earth elements and oxygen. Compared with other metallurgy preparation methods, the Mo-Tb-Dy high-temperature alloy is prepared by adopting powder metallurgy, and the technical problems of accurate control of pure rare earth material components, surface protection and coating of pure rare earth materials, forming and control of high-melting-point materials, control of densification processes of difficult-to-process materials and the like are solved.

(3) Fixing the preformed powder by using a silicone tube: compare with the fixed preforming powder of rubber tube, silica gel ductility is better for Mo-Tb-Dy powder is when cold isostatic pressing, and the degree of densification is higher, utilizes the fixed silicone tube of circular arc section of jurisdiction simultaneously, makes the straightness that hangs down of rod higher. The preformed powder is fixed by the silicone tube, so that the size of the prepared rod-shaped section is accurate and controllable, and the popularization and application of the Mo-Tb-Dy high-temperature alloy are facilitated.

(4) When the formed bar is sintered at high temperature, in order to ensure that the formed bar is uniformly heated and prevented from being oxidized at high temperature, the alloy bar is put into aluminum oxide powder for heating. The bar is transversely placed into the heating body, so that the bar is uniformly heated, and stress concentration is avoided.

Drawings

FIG. 1 is a flow chart of a preparation method according to the present invention;

FIG. 2 is a schematic structural view of a silicone tube, an arc tube piece and an elastic piece according to the present invention;

FIG. 3 is a cross-sectional view of FIG. 2;

FIG. 4 is a schematic view of a heating apparatus;

wherein, 1 is the silicone tube, 2 is the circular arc section of jurisdiction, 3 is the elastic component, 4 is the stopcock, 5 is preformed material, 6 is firing equipment, 7 is aluminium oxide, 8 is the preforming, 9 is first last spacer, 10 is second last spacer, 11 is third last spacer, 12 is last top, 13 is the depression bar, 14 is first lower spacer, 15 is last pressure power pole, 16 is second lower spacer, 17 is third lower spacer.

Detailed description of the preferred embodiments

In order to better understand the technical solution, the technical solution will be described in detail with reference to the drawings and the specific embodiments.