阅读说明：本技术 一种Fe-Ni-Co-Al-Mo超弹性合金及其制备方法 (Fe-Ni-Co-Al-Mo hyperelastic alloy and preparation method thereof ) 是由 张中武 黄涛 张洋 杜康 马亚玺 郁永政 黄楷岚 董凯 于 2021-07-19 设计创作，主要内容包括：本发明公开一种Fe-Ni-Co-Al-Mo超弹性合金及其制备方法,该超弹性合金的表达式为Fe-(a)Ni-(b)Co-(c)Al-(d)Mo-(e),合金表达式中a,b,c,d,e分别表示各对应主元的原子百分比含量,且满足以下条件：a为40～60,b为28～40,c为10～20,d为10～16,e为1～10,a+b+c+d+e＝100。该合金的制备方法中包括熔炼、轧制、固溶和时效处理。本发明的超弹性合金通过调整每种主元素的含量、热处理方式和时间来调控析出相的大小和体积分数,以获得优良的超弹性。本发明的超弹性合金可回复应变量可达1.5％,展现出良好的超弹性。(The invention discloses a Fe-Ni-Co-Al-Mo hyperelastic alloy and a preparation method thereof, wherein the expression of the hyperelastic alloy is Fe a Ni b Co c Al d Mo e In the alloy expression, a, b, c, d and e respectively represent the atom percentage content of each corresponding principal element, and the following conditions are satisfied: a is 40-60, b is 28-40, c is 10-20, d is 10-16, e is 1-10, and a + b + c + d + e is 100. The preparation method of the alloy comprises smelting, rolling, solid solution and aging treatment. The super-elastic alloy of the invention regulates the size and volume fraction of precipitated phases by adjusting the content of each main element, the heat treatment mode and the time, so as to obtain excellent super-elasticity. The super-elastic alloy can recover the strain amount to 1.5 percent and shows good super-elasticity.)

1. A super elastic alloy of Fe-Ni-Co-Al-Mo is characterized in that the expression of the super elastic alloy is Fe_aNi_bCo_cAl_dMo_eIn the alloy expression, a, b, c, d and e respectively represent the atom percentage content of each corresponding principal element, and the following conditions are satisfied: the alloy is prepared by the following steps of melting, rolling, solid solution treatment and aging treatment, wherein the a is 40-60, the b is 28-40, the c is 10-20, the d is 10-16, the e is 1-10, and the a + b + c + d + e is 100.

2. A method for preparing the Fe-Ni-Co-Al-Mo superelastic alloy according to claim 1, comprising the steps of:

(1) according to the atomic percentage of each element in the super-elastic alloy, selecting metal iron, metal nickel, metal cobalt, metal aluminum and metal molybdenum, and smelting the metal iron, the metal nickel, the metal cobalt, the metal aluminum and the metal molybdenum into an alloy casting;

(2) hot rolling and cold rolling;

(3) and (6) heat treatment.

3. The method for preparing Fe-Ni-Co-Al-Mo superelastic alloy according to claim 2, wherein in step (1), the smelting and forming process is performed under vacuum or inert gas protection, and the metal solution is required to be fully mixed during the smelting process to ensure that the components are sufficiently uniform.

4. The method for preparing a Fe-Ni-Co-Al-Mo superelastic alloy according to claim 2, wherein in step (2), said rolling conditions are: heating the casting to 900-1300 ℃, preserving heat for 1-3 h to homogenize the casting, then carrying out hot rolling with small deformation of 0-70% at 900-1300 ℃, and carrying out cold rolling with large deformation of more than or equal to 80% after cooling to room temperature.

5. The method for preparing Fe-Ni-Co-Al-Mo superelastic alloy according to claim 2, wherein in step (3), the heat treatment process is as follows: carrying out solution treatment at 800-1300 ℃ for 0-20 h, and carrying out aging treatment at 500-700 ℃ for 0.5-100 h after the temperature is up to room temperature.

Technical Field

The invention relates to a Fe-Ni-Co-Al-Mo hyperelastic alloy with hyperelasticity and a preparation method thereof, belonging to the technical field of iron-based hyperelastic alloy materials.

Background

The super-elastic alloy has important application in the aspects of aerospace materials, ship damping materials, embedded surgical medical materials and the like. The currently developed more mature super-elastic alloys mainly comprise Cu-based, Ti-based and Fe-based super-elastic alloys. Among them, Cu-based and Ti-based superelastic alloys have been developed for decades, while Fe-based superelastic alloys, which are superior in terms of performance and cost, have been discovered and studied by researchers since the beginning of this century. Iron-based superelastic alloys, such as FeMnAl-based and FeNiCoAl-based superelastic alloys, have the advantages of low cost, excellent mechanical properties, good processability and the like compared with the traditional NiTi-based superelastic alloys, and have attracted extensive research attention. Iron-based shape memory alloys have been used in a significant portion of life practice, and researchers have been working on putting newly developed iron-based memory alloys into production applications. In the superelasticity test of Fe-based alloys, the superelasticity is generally poor, because the martensitic transformation in Fe-based alloys is generally non-thermal elastic martensitic transformation, and the thermal elastic martensitic transformation is an indispensable condition for obtaining good superelasticity. In 2010, Tanaka et Al reported that Fe-28Ni-17Co-11.5Al-2.5Ta-0.05B (at%) shape memory alloys have a thermo-elastic martensitic transformation with high superelastic strain, high hardness, high strength, high damping properties and good cold workability with a maximum recoverable strain of up to 13.5%. According to the development of iron-based superelastic alloys, it can be seen that efforts to obtain large room temperature superelastic strains have been made by controlling the composition or optimizing the process to obtain a thermoelastic martensitic transformation. Different from Fe-Ni-Co-Al-Ta-B super-elastic alloy, Mo is added into Fe-Ni-Co-Al series alloy to promote the formation of a nanometer precipitated phase, so that the thermo-elastic martensite phase transformation is obtained under a reasonable heat treatment process, and the super-elasticity is realized by inducing the martensite phase transformation through stress in the working process of the alloy.

The invention patent application with publication number CN 103509988A discloses a polycrystalline Fe-Ni-Co-Al-Nb-B shape memory alloy with super elasticity and a preparation method thereof. The alloy comprises the following atomic percentage: 30-50% of Fe, 28-40% of Ni, 10-30% of Co, 8-15% of Al, 1-4% of Nb and 0.1-3% of B. The maximum recoverable strain of the shape memory alloy obtained by the invention can reach 10.5%, and the shape memory alloy has excellent superelasticity. The present invention is different from the present invention in terms of composition, and does not add an element B for suppressing the precipitation of a β phase. The invention obviously improves the superelasticity of the FeNiCoAl-based alloy by using the element Mo as a precipitated phase promoting element, and also improves the strength, the plasticity and the processability of the FeNiCoAl-based alloy.

The invention patent application with publication number CN 103233159A discloses a polycrystalline iron-based shape memory super-elastic alloy and a preparation method thereof. The alloy comprises the following atomic percentage: 55-65% of Fe, 25-30% of Ni, 10-13% of Al, 0.8-1% of Ta and some inevitable impurities. The polycrystalline iron-based super-elastic alloy has the characteristics of large recoverable strain, good super-elasticity, high strength, good processability and the like. The invention is different from the alloy in terms of alloy components, and adds Co element besides the least element of Mo, so that the alloy can be precipitated with a large amount of nano-phase to form reinforcement, and the martensite phase transformation is changed into the thermoelastic martensite phase transformation, thereby realizing the superelasticity.

Disclosure of Invention

The first technical problem to be solved by the invention is as follows: provides a composition design of an iron-based super-elastic alloy with excellent super-elasticity.

The second technical problem to be solved by the invention is: provides a preparation method of iron-based super-elastic alloy with excellent super-elasticity.

In order to solve the first technical problem, the invention provides an iron-based super-elastic alloy with excellent super-elasticity, and the component is Fe_aNi_bCo_cAl_dMo_eIn the alloy expression, a, b, c, d and e respectively represent the atom percentage content of each corresponding principal element, and the following conditions are satisfied: a is 40-60, b is 28-40, c is 10-20, d is 10-16, e is 1-10, and a + b + c + d + e is 100.

In order to solve the second technical problem, the invention provides a method for preparing the iron-based superelastic alloy, and the preparation method comprises the processes of smelting, rolling, solid solution and aging treatment.

The preparation method of the Fe-Ni-Co-Al-Mo super elastic alloy is characterized by comprising the following preparation processes:

(1) the method comprises the steps of selecting industrially used pure metal raw materials of metal iron, metal nickel, metal cobalt, metal aluminum and metal molybdenum, mixing the raw materials according to the atomic percentage content of 40-60% of Fe, 28-40% of Ni, 10-20% of Co, 10-16% of Al and 1-10% of Mo, and carrying out a smelting forming process in vacuum or inert gas protection. The metal solution needs to be thoroughly mixed during the smelting process to ensure that the components are sufficiently uniform.

(2) Heating the casting to 900-1300 ℃, preserving heat for 1-3 h to homogenize the casting, then carrying out hot rolling with small deformation of 0-70% at 900-1300 ℃, and carrying out cold rolling with large deformation of more than or equal to 90% after cooling to room temperature.

(3) The rolled material is subjected to solution treatment for 0-20 h at 800-1300 ℃, and then is subjected to aging treatment for 0.5-100 h at 500-700 ℃ after being cooled to room temperature.

Compared with the prior art, the invention has the beneficial effects that:

according to the invention, reasonable component proportion is carried out on each alloy element, so that the alloy parent phase has a face-centered cubic structure, thermoelastic martensite phase transformation can be well generated, ordered precipitated phases can be precipitated from the alloy parent phase, the strength and the superelasticity of the alloy are increased, and the ductility of the alloy can be effectively improved. The strength and super-elasticity of the alloy are increased by obtaining strong texture through a reasonable rolling process. The strength of an austenite parent phase is improved through reasonable solution aging treatment, the critical stress of stress-induced martensite phase transformation is reduced, and the irreversible deformation is reduced, so that the iron-based super-elastic alloy with super elasticity and high strength is obtained.

Drawings

FIG. 1 is a stress-strain curve of Fe-Ni-Co-Al-Mo superelastic alloy of the present invention after aging for 5h, loaded-unloaded at room temperature;

FIG. 2 is a microstructure observed by an optical microscope after aging the Fe-Ni-Co-Al-Mo superelastic alloy of the invention for 5 h.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

Example 1

Selecting industrially used pure metal raw materials of metallic iron, metallic nickel, metallic cobalt, metallic aluminum and metallic molybdenum, mixing according to the atomic percentage content of Fe 41.5%, Ni 28%, Co 17%, Al 11.5% and Mo 2%, smelting by a vacuum non-consumable electric arc furnace under the protection of argon, uniformly mixing the metal solution by using a magnetic stirring technology in the smelting process, repeatedly smelting the alloy for 5 times in the smelting process, and finally performing suction casting to form a columnar piece. The casting was heated to 1200 ℃ for homogenization for 2h, water cooled, and hot rolled from 20mm to 2mm at room temperature. And aging the rolled sample at 600 ℃ for 5h, and then cooling with water.

The stress-strain curve obtained by loading and unloading the polycrystalline Fe-Ni-Co-Al-Mo superelastic alloy prepared in the example at room temperature is shown in the attached figure 1. As can be seen from the stress-strain curve shown in FIG. 1, the polycrystalline Fe-Ni-Co-Al-Mo superelastic alloy of this composition has a recoverable strain of 1.5% at room temperature.

The invention discloses a Fe-Ni-Co-Al-Mo hyperelastic alloy and a preparation method thereof, wherein the expression of the hyperelastic alloy is Fe_aNi_bCo_cAl_dMo_eIn the alloy expression, a, b, c, d and e respectively represent the atom percentage content of each corresponding principal element, and the following conditions are satisfied: a is 40-60, b is 28-40, c is 10-20, d is 10-16, e is 1-10, and a + b + c + d + e is 100. The preparation method of the alloy comprises smelting, rolling, solid solution and aging treatment. The super-elastic alloy of the invention regulates the size and volume fraction of precipitated phases by adjusting the content of each main element, the heat treatment mode and the time, so as to obtain excellent super-elasticity. The super-elastic alloy can recover the strain amount to 1.5 percent and shows good super-elasticity.