阅读说明：本技术 一种镍钴锰磁性超弹性形状记忆合金及其制备方法 (Nickel-cobalt-manganese magnetic superelasticity shape memory alloy and preparation method thereof ) 是由 吴志刚 向婉婉 郭锦培 钟敏婷 刘义捷 于 2019-11-20 设计创作，主要内容包括：本发明公开了一种镍钴锰磁性超弹性形状记忆合金及其制备方法。本发明的镍钴锰磁性超弹性形状记忆合金的化学组成按原子百分比计为：镍48at％～50at％,钴1at％～4at％,锰34at％～39at％,铁0～5at％,锡8at％～9at％,其制备方法包括以下步骤：1)将镍、钴、锰、铁和锡按照设定的原子百分比混合加入金属熔炼炉；2)将适量锰加入金属熔炼炉补充熔炼过程中锰的挥发损失；3)将保护气充入金属熔炼炉,进行熔炼。本发明的镍钴锰磁性超弹性形状记忆合金的塑性大、强度高、机械循环稳定性好,且具有大于4％的超弹性能。(The invention discloses a nickel-cobalt-manganese magnetic superelasticity shape memory alloy and a preparation method thereof. The chemical composition of the nickel-cobalt-manganese magnetic superelasticity shape memory alloy is as follows by atomic percentage: 48 at% -50 at% of nickel, 1 at% -4 at% of cobalt, 34 at% -39 at% of manganese, 0-5 at% of iron and 8 at% -9 at% of tin, wherein the preparation method comprises the following steps: 1) mixing nickel, cobalt, manganese, iron and tin according to a set atomic percentage, and adding the mixture into a metal smelting furnace; 2) adding a proper amount of manganese into a metal smelting furnace to supplement the volatilization loss of manganese in the smelting process; 3) and (4) filling the protective gas into a metal smelting furnace for smelting. The nickel-cobalt-manganese magnetic superelasticity shape memory alloy has the advantages of high plasticity, high strength, good mechanical cycle stability and more than 4% of superelasticity.)

1. A nickel-cobalt-manganese magnetic superelasticity shape memory alloy is characterized in that: the chemical composition comprises the following components in atomic percentage: 48 at% -50 at% of nickel, 1 at% -4 at% of cobalt, 34 at% -39 at% of manganese, 0-5 at% of iron and 8 at% -9 at% of tin.

2. The nickel-cobalt-manganese magnetic superelastic shape memory alloy of claim 1, wherein: the chemical composition comprises the following components in atomic percentage: 48 at% of nickel, 4 at% of cobalt, 34 at% of manganese, 5 at% of iron and 9 at% of tin.

3. The method for preparing the nickel-cobalt-manganese magnetic superelastic shape memory alloy of claim 1 or 2, wherein: the method comprises the following steps:

1) mixing nickel, cobalt, manganese, iron and tin according to a set atomic percentage, and adding the mixture into a metal smelting furnace;

2) adding a proper amount of manganese into a metal smelting furnace to supplement the volatilization loss of manganese in the smelting process;

3) and filling the protective gas into a metal smelting furnace, and smelting to obtain the nickel-cobalt-manganese magnetic superelasticity shape memory alloy.

4. The production method according to claim 3, characterized in that: the purity of the nickel, the cobalt, the manganese, the iron and the tin in the step 1) is not lower than 99.995 at%.

5. The production method according to claim 3 or 4, characterized in that: the addition amount of the manganese in the step 2) is 0.8-1.2% of the total mass of the nickel, the cobalt, the manganese, the iron and the tin in the step 1).

6. The production method according to claim 3, characterized in that: and 3) the protective gas is argon.

7. The production method according to claim 3, 4 or 6, characterized in that: smelting current of the smelting in the step 3) is not less than 80A.

8. The production method according to claim 3, 4 or 6, characterized in that: and 3) smelting for at least 2 times on the front and back surfaces respectively, wherein the smelting time is at least 5min each time.

Technical Field

The invention relates to a nickel-cobalt-manganese magnetic superelasticity shape memory alloy and a preparation method thereof.

Background

The nickel-manganese magnetic shape memory alloy has excellent performances of magnetic induced recovery strain, large output stress, giant magnetocaloric effect, high response frequency, elastic magnetocaloric effect and the like, and is a potential new generation of driving and sensing material following piezoelectric ceramics and magnetostrictive materials. However, the intrinsic brittleness of intermetallic compounds severely limits the practical application of such materials.

At present, the nickel-manganese magnetic shape memory alloy is plasticized by a method of introducing a plastic second phase (gamma phase), the average size of the traditional gamma phase crystal grains is large (in the order of tens of microns), and although the typical plastic deformation mechanism of the traditional gamma phase crystal grains can effectively enhance the overall strength and plasticity of the alloy, the martensite phase transformation lattice shear of a Heusler matrix phase can be seriously hindered, so that the shape memory effect and the superelasticity of the alloy are greatly reduced.

Therefore, there is a need to develop a magnetic shape memory alloy having high plasticity, high strength, good mechanical cycle stability, and super-elastic properties.

Disclosure of Invention

The invention aims to provide a nickel-cobalt-manganese magnetic superelasticity shape memory alloy and a preparation method thereof.

The technical scheme adopted by the invention is as follows:

a nickel-cobalt-manganese magnetic superelasticity shape memory alloy comprises the following chemical compositions in atomic percentage: 48 at% -50 at% of nickel, 1 at% -4 at% of cobalt, 34 at% -39 at% of manganese, 0-5 at% of iron and 8 at% -9 at% of tin.

Preferably, the nickel-cobalt-manganese magnetic superelasticity shape memory alloy comprises the following chemical compositions in atomic percentage: 48 at% of nickel, 4 at% of cobalt, 34 at% of manganese, 5 at% of iron and 9 at% of tin.

The preparation method of the nickel-cobalt-manganese magnetic superelasticity shape memory alloy comprises the following steps:

1) mixing nickel, cobalt, manganese, iron and tin according to a set atomic percentage, and adding the mixture into a metal smelting furnace;

2) adding a proper amount of manganese into a metal smelting furnace to supplement the volatilization loss of manganese in the smelting process;

3) and filling the protective gas into a metal smelting furnace, and smelting to obtain the nickel-cobalt-manganese magnetic superelasticity shape memory alloy.

Preferably, the purity of the nickel, the cobalt, the manganese, the iron and the tin in the step 1) is not lower than 99.995 at%.

Preferably, the addition amount of the manganese in the step 2) is 0.8-1.2% of the total mass of the nickel, the cobalt, the manganese, the iron and the tin in the step 1).

Preferably, the protective gas in step 3) is argon.

Preferably, the smelting current of the smelting in the step 3) is not less than 80A.

Preferably, the smelting in the step 3) is carried out for at least 2 times on the front side and the back side respectively, and each time is carried out for at least 5 min.

The invention has the beneficial effects that: the nickel-cobalt-manganese magnetic superelasticity shape memory alloy has the advantages of high plasticity, high strength, good mechanical cycle stability and more than 4% of superelasticity.

Drawings

FIG. 1 shows as-cast Ni of example 1₄₈Co₄Mn₃₄Fe₅Sn₉Back-scattered SEM images of the alloys.

FIG. 2 shows as-cast Ni of example 1₄₈Co₄Mn₃₄Fe₅Sn₉XRD pattern of the alloy.

FIG. 3 shows as-cast Ni of example 1₄₈Co₄Mn₃₄Fe₅Sn₉Magnetization versus temperature curve of the alloy.

FIG. 4 shows as-cast Ni of example 1₄₈Co₄Mn₃₄Fe₅Sn₉Stress-strain relationship of the alloy when stretched at room temperature.

FIG. 5 shows as-cast Ni of example 1₄₈Co₄Mn₃₄Fe₅Sn₉The stress-strain relationship of the alloy was taken over 20 compression cycles at room temperature.

FIG. 6 shows as-cast Ni of example 1₄₈Co₄Mn₃₄Fe₅Sn₉Modulus of elasticity and energy dissipation curves of the alloy subjected to 20 compression cycles at room temperature.

FIG. 7 shows as-cast Ni of example 1₄₈Co₄Mn₃₄Fe₅Sn₉Maximum strain and residual strain curves of the alloy subjected to 20 compression cycles at room temperature.

Detailed Description

The invention will be further explained and illustrated with reference to specific examples.