阅读说明：本技术 利用超声空化工艺制备合金材料的方法及所得合金材料 (Method for preparing alloy material by utilizing ultrasonic cavitation process and obtained alloy material ) 是由 林卓贤 杨铭 徐蕾 刘建 贺会军 王志刚 安宁 赵朝辉 张江松 卢茂成 朱学新 于 2020-12-31 设计创作，主要内容包括：本发明涉及一种利用超声空化工艺制备合金材料的方法及所得细晶合金材料。一种制备合金材料的方法：对熔融态合金进行超声空化破碎处理,之后定型形成合金材料；在所述超声空化破碎处理中,超声波分散设备的频率为100～1000kHz,产生的冲击波和微射流的速度为30～110m/s,使所述熔融态合金的运动加速度达到30～100倍重力加速度。本发明解决了传统方法中存在的工艺繁杂、设备要求高、易引入杂质,并且细化组织不均匀、组织受热易长大、组织在服役过程中不稳定、组织不可遗传等问题,同时该方法原料易得,设备简单,工艺流程短,效率高,成本低,适合工业化生产。(The invention relates to a method for preparing an alloy material by utilizing an ultrasonic cavitation process and an obtained fine-grained alloy material. A method for preparing an alloy material comprises the following steps: carrying out ultrasonic cavitation crushing treatment on the molten alloy, and then shaping to form an alloy material; in the ultrasonic cavitation and crushing treatment, the frequency of ultrasonic dispersion equipment is 100-1000 kHz, the speed of generated shock waves and micro-jet is 30-110 m/s, and the motion acceleration of the molten alloy reaches 30-100 times of the gravity acceleration. The invention solves the problems of complex process, high equipment requirement, easy introduction of impurities, uneven refined tissue, easy growth of the heated tissue, unstable tissue in the service process, non-heritable tissue and the like in the traditional method, and simultaneously the method has the advantages of easily obtained raw materials, simple equipment, short process flow, high efficiency, low cost and suitability for industrial production.)

1. A method for preparing an alloy material by utilizing an ultrasonic cavitation process is characterized by comprising the following steps:

ultrasonic cavitation crushing treatment is carried out on the molten alloy by utilizing ultrasonic dispersion equipment, and then the alloy material is formed through shaping;

in the ultrasonic cavitation and crushing treatment, the frequency of ultrasonic dispersion equipment is 100-1000 kHz, the speed of generated shock waves and micro-jet is 30-110 m/s, and the motion acceleration of the molten alloy reaches 30-100 times of the gravity acceleration.

2. The method according to claim 1, wherein the time of the ultrasonic cavitation disruption treatment is 20-120 min.

3. The method of claim 1, wherein the molten alloy is one of a tin alloy, a bismuth alloy, an indium alloy, an aluminum alloy, and a copper alloy.

4. The method of claim 1, wherein during the ultrasonic cavitation disruption treatment, the temperature is maintained above the liquidus of the alloy.

5. The method of claim 1, wherein the ultrasonic cavitation disruption treatment is performed in air, nitrogen, or an inert atmosphere.

6. The method of claim 1, wherein said sizing comprises:

cooling to prepare an alloy ingot, and then drawing the ingot into a strip material and a wire material;

or atomizing the molten alloy into alloy powder;

alternatively, the molten alloy is cast into alloy bars, sheets or profiles.

7. The method of claim 1, wherein the alloy is a tin-antimony alloy and the ultrasonic dispersion apparatus has a frequency of 800 kHz.

8. The method of claim 1, wherein the alloy is a bismuth antimony alloy and the ultrasonic dispersion apparatus has a frequency of 750 kHz.

9. The method of claim 1, wherein the alloy is an aluminum strontium alloy and the ultrasonic dispersion apparatus has a frequency of 1000 kHz.

10. A fine grained alloy material obtained by the method of any one of claims 1 to 9.

Technical Field

The invention relates to the technical field of metallurgy, in particular to a method for preparing an alloy material by utilizing an ultrasonic cavitation process and an obtained fine-grained alloy material.

Background

The quality of the structure and properties of the alloy article depends, above all, on the initial structure of the ingot. Compared with the ingot with the coarse crystal structure, the ingot with the fine crystal structure has a series of advantages: the cutting amount during machining is reduced, and the yield is improved; the cast ingot with uniform and fine structure has small casting stress, so that the plastic deformation capacity of the cast ingot is improved; the semi-finished product made of the cast ingot with the fine crystalline structure has higher mechanical performance; therefore, it is necessary to perform a structure-refining treatment on the alloy.

The traditional metallurgical tissue refining treatment method mainly adds a small amount of refiner. With the continuous progress and development of alloy manufacturing industry and processing industry, the grain refiner has also been improved continuously. However, the addition of the refiner is still insufficient in the grain refining process, and when certain specific elements are contained in the melt, the refining effect is lost, i.e., a "poisoning" phenomenon occurs.

The tissue thinning treatment is carried out by a physical action method mainly by adopting electromagnetic stirring. However, electromagnetic stirring imposes severe requirements on the melt casting temperature, and the casting temperature needs to be controlled to ensure that the sizes of the crystal grains and the branch cells at the lower and central parts of the induction coil are close to each other.

In recent years, the discovery and research of liquid structure transformation provide a new opportunity for the cognition of liquid-solid dependence relationship. In the material production and scientific research practice, people have deeper understanding on the alloy liquid structure, particularly find the phenomenon of liquid-liquid phase structure transformation induced by external force, and recognize that liquid-solid phase organization inheritance exists in the aspects of liquid-liquid phase structure transformation and material performance. By changing the liquid phase structure of the melt, the alloy material with uniformly refined solidification structure is obtained, and the mechanical property, the process property and the service stability of the material are improved.

How to realize the transformation of the melt liquid-liquid phase structure to prepare the fine-grained alloy product is a difficult point in the production of specific engineering application and process.

Disclosure of Invention

The invention aims to provide a method for preparing an alloy material, which avoids the defects of the traditional method, solves the problems of complex process, high equipment requirement, easy introduction of impurities, uneven refined tissue, easy growth of heated tissue, unstable tissue in the service process, unsuccessfully inherited tissue and the like in the traditional method, and is simple in equipment, short in process flow, high in efficiency, low in cost and suitable for industrial production.

In order to achieve the above purpose, the invention provides the following technical scheme:

a method of making an alloy material comprising:

carrying out ultrasonic cavitation crushing treatment on the molten alloy, and then shaping to form an alloy material;

in the ultrasonic cavitation and crushing treatment, the frequency of ultrasonic dispersion equipment is 100-1000 kHz, the speed of generated shock waves and micro-jet is 30-110 m/s, and the motion acceleration of the molten alloy reaches 30-100 times of the gravity acceleration.

The method utilizes ultrasonic dispersion equipment to generate cavitation bubbles in a melt, and then utilizes transient high temperature and high pressure generated when the cavitation bubbles collapse, high-speed shock waves and micro-jet flow to ensure larger shearing force and higher shearing speed, so that the repeated crushing and dispersion of similar solid type atomic clusters in the melt are realized, the atomic clusters which can be directly used as critical crystal nuclei in the melt are reduced or disappeared, the short-range ordered structure in the melt is broken and irreversible transformation occurs, the inherent nucleation substrate in the melt becomes dispersed and fine, the density of the nucleation substrate is increased, the liquid-liquid phase structure transformation of the melt is realized, and the melt subjected to the liquid-liquid phase structure transformation is treated by a subsequent process to prepare the optimal performance melt structure transformation alloy material with uniform dispersion, single distribution and tissue refinement of the crystal nuclei.

The process conditions of ultrasonic dispersion are very critical to the process, the frequency is preferably 100-1000 kHz, so that the speed of the generated shock wave and the micro jet reaches 30-110 m/s, and the solid-like atomic clusters reach the maximum linear speed under the driving of the shock wave and the micro jet generated when cavitation bubbles collapse. According to the formula of acceleration a ═ v²The acceleration of the solid-like atomic cluster (namely molten alloy) reaches 30-100 times of gravity acceleration; under the action of high-speed shearing force, the quasi-solid type atomic clusters are extruded and crushed, so that the atomic clusters which can be directly used as critical crystal nuclei in the melt are reduced or disappeared, the short-distance ordered structure in the melt is broken, irreversible transformation occurs, the inherent nucleation substrate in the melt becomes dispersed and fine, the density of the nucleation substrate is increased, and the liquid-liquid phase structure transformation of the melt is realized. The duration of the ultrasonic cavitation dispersion process is usually within 20-120 min until the formed melt is uniform and stable, and the structure in the melt is finer and disordered.

Further, the molten alloy can be obtained by directly melting the block alloy or melting a single metal block after being prepared in proportion; the alloys include, but are not limited to, tin alloys, bismuth alloys, indium alloys, aluminum alloys, copper alloys, and the like. In the alloy smelting process, according to the stability and the oxidation resistance of different alloys, the alloy can be smelted under the conditions of air, nitrogen, argon or other atmospheres.

Further, the temperature is kept above the liquidus line of the alloy in the ultrasonic cavitation crushing treatment process, so that the integral temperature of the melt is uniform and stable.

Further, the sizing comprises:

cooling to prepare an alloy ingot, and then drawing the ingot into a strip material and a wire material;

or atomizing the molten alloy into alloy powder;

alternatively, the molten alloy may be cast into alloy bars, sheets, or processed into shaped articles.

Further, the alloy is tin-antimony alloy, and the frequency of the ultrasonic dispersion equipment is 800 kHz.

Further, the alloy is bismuth-antimony alloy, and the frequency of the ultrasonic dispersion equipment is 750 kHz.

Further, the alloy is an aluminum strontium alloy, and the frequency of the ultrasonic dispersion equipment is 1000 kHz.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

FIG. 1 is a schematic flow diagram of a method of making a melt structure transition alloy according to the present invention;

FIG. 2 is a diagram of the growth process of cavitation bubbles in the alloy preparation method provided by the invention;

FIG. 3 is a graph of the change in radius of the cavitation bubbles of FIG. 2 at various stages;

FIG. 4 is a photograph of the microstructures of the materials prepared in comparative example 1 and example 1;

FIG. 5 is a photograph of the microstructures of the materials prepared in comparative example 2 and example 2;

fig. 6 is a microstructure photograph of the materials prepared in comparative example 3 and example 3.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to examples, but it will be understood by those skilled in the art that the following examples are only illustrative of the present invention and should not be construed as limiting the scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The raw materials, reagents or instruments used are not indicated by manufacturers, and all the raw materials, the reagents or the instruments are conventional products which can be obtained by commercial purchase or can be prepared according to the prior art.

Example 1

The procedure shown in FIG. 1:

putting 4kg of Sn-5% Sb alloy into a graphite smelting furnace of smelting-ultrasonic cavitation integrated equipment, and heating to 300 ℃ under the protection of argon atmosphere to completely melt the alloy to form uniform liquid-phase melt; raising the temperature of the melt to 550 ℃, and keeping the integral temperature of the melt uniform; starting an ultrasonic cavitation device to adjust the frequency to 800kHz, carrying out ultrasonic cavitation crushing dispersion for 60min, wherein cavitation bubbles are generated in the process, the growth process is shown as figure 2, the process of bubble generation, bubble growth, bubble explosion, new micronucleus generation and the like is carried out, and the particle size change of the bubbles is shown as figure 3 in the process; then the ultrasonic cavitation equipment is closed; and (3) casting the melt into an iron mold for cooling to obtain a melt structure transformation Sn-5% Sb alloy ingot, and then drawing the ingot to obtain a melt structure transformation Sn-5% Sb alloy wire material to obtain a structure shown in figure 4.

Comparative example 1

Putting 4kg of Sn-5% Sb alloy into a graphite smelting furnace of smelting-ultrasonic cavitation integrated equipment, and heating to 300 ℃ under the protection of argon atmosphere to completely melt the alloy to form uniform liquid-phase melt; raising the temperature of the melt to 550 ℃, and keeping the integral temperature of the melt uniform; after the temperature is kept for 60min, the melt is poured into an iron mold for cooling to obtain a conventional Sn-5% Sb alloy ingot, and then the ingot is drawn to obtain a conventional Sn-5% Sb alloy wire material, so that the structure shown in figure 4 is obtained.

Comparing example 1 with comparative example 1, it is apparent that the structure of example 1 is finer and more uniform than that of comparative example 1.

Example 2

Placing 3kg of Bi-10% Sb alloy into a graphite smelting furnace of smelting-ultrasonic cavitation integrated equipment, heating to 400 ℃ under the protection of argon atmosphere, and completely melting the alloy to form uniform liquid-phase melt; raising the temperature of the melt to 700 ℃, and keeping the integral temperature of the melt uniform; starting the ultrasonic cavitation equipment to adjust the frequency to 750 kHz; after 90min of ultrasonic cavitation, crushing and dispersing, closing the ultrasonic cavitation equipment; and pouring the melt into a sand mold for air cooling to obtain a Bi-10% Sb alloy bar with the melt structure changed, and obtaining the structure shown in figure 5.

Comparative example 2

Placing 3kg of Bi-10% Sb alloy into a graphite smelting furnace of smelting-ultrasonic cavitation integrated equipment, heating to 400 ℃ under the protection of argon atmosphere, and completely melting the alloy to form uniform liquid-phase melt; raising the temperature of the melt to 700 ℃, and keeping the integral temperature of the melt uniform; after the heat preservation for 90min, the melt is poured into a sand mold for air cooling to obtain a conventional Bi-10% Sn alloy bar, and the structure shown in figure 5 is obtained.

Comparing example 2 with comparative example 2, it is apparent that the structure of example 2 is finer and more uniform than that of comparative example 2.

Example 3

Placing 10kg of Al-18% Si alloy into a graphite smelting furnace of smelting-ultrasonic cavitation integrated equipment, heating to 760 ℃ under the protection of nitrogen atmosphere, and completely melting the alloy to form uniform liquid-phase melt; raising the temperature of the melt to 950 ℃, and keeping the integral temperature of the melt uniform; starting the ultrasonic cavitation equipment to adjust the frequency to 1000 kHz; after 30min of ultrasonic cavitation, crushing and dispersing, closing the ultrasonic cavitation equipment; the melt was poured into a hot metal mold and cooled to obtain a cast irregularly shaped part of Al-18% Si alloy with a transformed melt structure, and the structure shown in FIG. 6 was obtained.

Comparative example 3

Placing 10kg of Al-18% Si alloy into a graphite smelting furnace of smelting-ultrasonic cavitation integrated equipment, heating to 760 ℃ under the protection of nitrogen atmosphere, and completely melting the alloy to form uniform liquid-phase melt; raising the temperature of the melt to 950 ℃, and keeping the integral temperature of the melt uniform; after 30min of heat preservation, the melt is poured into an iron mold for cooling to obtain a conventional Al-18% Si alloy cast special-shaped piece, and the structure shown in figure 6 is obtained.

Comparing example 3 with comparative example 3, it is apparent that the structure of example 3 is finer and more uniform than that of comparative example 3.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.