An easily activated Ti-Fe-RE-Mn-Zr-Zn-Sb based hydrogen storage alloy and preparation method thereof

Abstract

The present invention relates to the technical field of hydrogen storage alloys, and in particular to an easily activated Ti-Fe-RE-Mn-Zr-Zn-Sb-based hydrogen storage alloy and a preparation method thereof. The chemical formula of the alloy is: Ti 1.1 Fe 0.8 Sm 0.04‑x Nd x Mn 0.35‑y‑z‑m Zr y Zn z Sb m , where x, y, z, and m are atomic ratios, with 0.01≤x≤0.04, 0.05≤y≤0.15, 0.02≤z≤0.08, and 0.01≤m≤0.05. The preparation method involves induction melting under an argon atmosphere to obtain an alloy ingot. The ingot is then mechanically crushed and subjected to a short period of mechanical ball milling to obtain an alloy powder with a nanocrystalline structure. The addition of small amounts of rare earth elements (Sm and Nd) and metals (Mn, Zr, Zn, and Sb) significantly enhances the alloy's hydrogen storage and activation properties. The rare earth elements readily form SmH₃ and NdH₃ during the initial hydrogen absorption, providing catalytically active centers for the alloy's activation. Mn forms the intermetallic compound ZrMn₂ with Zr, and Zn forms the SbZn phase with Sb, significantly improving the alloy's activation properties without significantly reducing its hydrogen storage capacity. Short-term ball milling significantly reduces grain size, improves the surface condition of the alloy particles, and significantly increases the crystal defect density, resulting in the alloy possessing excellent activation properties.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen storage alloy materials, and in particular to an easily activated Ti-Fe-RE-Mn-Zr-Zn-Sb-based hydrogen storage alloy and a preparation method thereof. Background Art

[0002] Hydrogen is currently attracting increasing attention due to its lightweight, high-energy density, and environmentally friendly properties, with potential applications in fuel cell vehicles and nickel-metal hydride batteries. However, the development of hydrogen as a 21st-century energy carrier will depend largely on its storage properties. Metal hydrides are currently the most commonly used hydrogen storage method due to their long charge-discharge cycle life, high energy density, good reversibility, and good environmental compatibility.

[0003] TiFe alloy is one of the most promising hydrogen storage alloys due to its excellent cycling performance, high hydrogen storage capacity, low room temperature equilibrium platform (0.41MPaH2) and low cost. However, the main disadvantages of TiFe alloy as a hydrogen storage material in commercial applications are poor absorption / desorption kinetics, difficulty in activation, the need for high temperature and high hydrogen pressure activation treatment, and low activation performance of TiFe alloy. Summary of the Invention

[0004] The main purpose of the present invention is to provide an easily activated Ti-Fe-RE-Mn-Zr-Zn-Sb-based hydrogen storage alloy and a preparation method thereof, so as to solve the problem of low activation performance of TiFe alloy in the prior art. Through the present invention, the activation performance of the alloy is greatly improved. The present invention achieves its purpose through the following technical solutions.

[0005] The first aspect of the present invention provides a high-capacity, easily activated Ti-Fe-RE-Mn-Zr-Zn-Sb based hydrogen storage alloy, which is characterized in that the alloy contains multiple rare earth and transition metal elements, and its composition is: Ti 1.1 Fe 0.8 Sm 0.04- x Nd x Mn 0.35-y-z-m Zr y Zn z Sb m , wherein x, y, z, and m are atomic ratios, 0.01≤x≤0.04, 0.05≤y≤0.15, 0.02≤z≤0.08, and 0.01≤m≤0.05. The preferred atomic ratio is x:y:z:m=0.02:0.12:0.04:0.03.

[0006] A second aspect of the present invention provides a method for preparing a high-capacity, easily activated Ti-Fe-RE-Mn-Zr-Zn-Sb-based hydrogen storage alloy, the preparation steps comprising:

[0007] Step 1: Ingredients: Ti according to the chemical formula 1.1 Fe 0.8 Sm 0.04-x Nd x Mn 0.35-y-z-m Zr y Zn z Sb m The ingredients are prepared, wherein the Sm, Nd, Mn, Zn and Sb in the chemical formula are increased by 5%-10% of the burn-off amount during the preparation, and the metal purity of the raw materials is ≥99.5%.

[0008] Step 2: Melting: Place the prepared raw materials in the zirconia crucible in order, place the pure iron rod vertically along the crucible wall, and add other metal raw materials in the following order: place the block rare earth Sm and Nd at the bottom of the crucible, place the sponge Ti and Zr on top of the rare earth Sm and Nd, place the electrolytic Mn on top of the sponge Ti and Zr, and finally add the metal Zn and Sb. Place the prepared raw materials in the crucible of the induction melting furnace in order, cover the furnace, and evacuate to 1×10 -2 -5×10 -5 Pa pressure, filled with 0.01-0.1MPa pressure of pure argon as a protective gas, the melting temperature is 1500-1650 ° C, to obtain molten Ti 1.1 Fe 0.8 Sm 0.04-x Nd x Mn 0.35-y-z-m Zr y Zn z Sb m The liquid master alloy is kept in a molten state for 3-5 minutes, and then poured into a copper casting mold to obtain a master alloy ingot.

[0009] Step 3: Mechanical ball milling: 1.1 Fe 0.8 Sm 0.04-x Nd x Mn 0.35-y-z-m Zr y Zn z Sb m After the alloy is mechanically crushed and passed through a 200-mesh sieve, it is placed into a stainless steel ball mill together with stainless steel grinding balls. After vacuuming, it is filled with high-purity argon gas and ball milled in an omnidirectional planetary high-energy ball mill for 0.5-2 hours, preferably 45 minutes, with a ball-to-material ratio of 1:20 and a rotation speed of 350 rpm.

[0010] Structure and performance testing: XRD was used to test the phase structure of the as-cast and ball-milled powders. High-resolution transmission electron microscopy (HRTEM) and scanning electron microscopy (SEM) were used to observe the morphology and microstructure of the ball-milled alloy particles. Selected area electron diffraction (SAED) was used to determine the crystalline state of the alloy. A semi-automatic Sieverts device was used to test the hydrogen absorption activation performance, hydrogen storage capacity, and hydrogen absorption and desorption kinetics of the alloy powders. The hydrogen absorption temperature was 30°C and the initial hydrogen pressure was 3 MPa; the hydrogen desorption temperature was 30°C and the hydrogen desorption was carried out at 1×10 -4 Carried out under MPa pressure.

[0011] TiFe alloys prepared by mechanical alloying and annealing, where Fe is substituted with Ni and Mn, respectively, not only increase the hydrogen storage capacity but also enhance the cycle life of the alloy. The results show that the substitution of Mn, V, Ni, and Pd for Fe plays a significant role in the hydrogen storage properties of TiFe alloys. The addition of Zr allows TiFe alloys to absorb hydrogen under moderate temperature-pressure conditions.

[0012] Mechanical ball milling, cold rolling, etc. are used for the synthesis and modification of hydrogen storage materials. These processes can introduce non-equilibrium phases, nanocrystalline structures and active sites, such as defects or grain boundaries, which can promote hydrogen absorption kinetics. Mechanical alloying and mechanical ball milling are one of the effective ways to improve the hydrogen adsorption / desorption properties of TiFe alloys. This method has a positive effect on the solid-state hydrogen storage of TiFe alloys, such as reducing particle size and creating new clean surfaces. Studies have confirmed the close relationship between the grain size of TiFe alloys and their hydrogen absorption activation properties. The smaller the grain size, the better the activation performance. In addition to reducing the particle size, ball milling also forms a clean surface, which promotes the absorption of hydrogen during the activation process of the alloy. Studies have found that TiFe alloy powder prepared by mechanical alloying (ball milling) with a small amount of Pd can absorb hydrogen without activation.

[0013] The present invention alloys the multi-element rare earth elements Sm and Nd and the transition metals Mn, Zr, Zn, and Sb, thereby reducing the activation conditions of the TiFe alloy and shortening the activation cycle. The as-cast sample is then ball-milled for varying periods of time. It is anticipated that a TiFe alloy with excellent activation properties and hydrogen absorption and desorption kinetics can be obtained by combining element substitution with short-term ball milling. The optimal ball milling time was determined by testing and analyzing the alloy's structure, activation properties, thermodynamics, and kinetic properties. Studies have shown that the alloy prepared by combining the alloy composition of the present invention with the ball milling process exhibits excellent activation properties and fully meets the performance requirements of the alloy for practical applications.

[0014] The application of the technical solution of the present invention has the following technical effects:

[0015] Compared with existing technologies, the advantages of the present invention lie in significantly increasing the activation properties of the alloy by adding a small amount of multi-component rare earth elements and transition metals. Combined with mechanical ball milling, the alloy's grain size is significantly reduced, and a large number of crystal defects are formed, increasing hydrogen nucleation sites and diffusion channels. This further reduces the alloy's thermal stability and improves its hydrogen absorption and desorption kinetics, resulting in a hydrogen storage material with excellent hydrogen absorption and desorption kinetics. The preparation process is simple and easy to operate, making it particularly suitable for large-scale production of TiFe alloys. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0017] Figure 1 XRD diffraction spectra of the cast alloys of Examples 1-6;

[0018] Figure 2 The SEM morphology of the ball-milled powder of Examples 1-6;

[0019] Figure 3 XRD patterns of the ball-milled alloys of Examples 1-6;

[0020] Figure 4 HRTEM morphology of the ball-milled alloys of Examples 1-6. DETAILED DESCRIPTION

[0021] It should be noted that, unless there is a conflict, the embodiments and features in the embodiments of this application may be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments. The design concept and mechanism of the present invention will be further described in detail in conjunction with the drawings and embodiments to make the technical solution of the present invention more clear.

[0022] In terms of composition design, the present invention utilizes Ti and Fe, elements with abundant reserves and low cost, facilitating large-scale industrial application. Research has shown that multi-element alloying can significantly improve the activation properties of TiFe alloys. In particular, the addition of a small amount of rare earth elements can significantly improve the activation properties of the alloy, significantly shorten the incubation time during alloy activation, and significantly increase the hydrogen storage capacity. This is because rare earth elements readily react with hydrogen atoms to form rare earth hydrides SmH3 and NdH3, which serve as catalytically active centers for the alloy. Zr and Mn can form a ZrMn2 phase, an intermetallic compound that significantly enhances activation ability and hydrogen storage capacity. The addition of Sb and Zn significantly improves the corrosion resistance of the alloy, while the resulting SbZn phase enhances the activation properties of the alloy. In terms of alloy preparation, mechanical ball milling significantly reduces the grain size of the alloy while significantly increasing the grain boundaries and defect density. This provides pathways for rapid diffusion of hydrogen atoms within the alloy, thereby significantly improving the hydrogen absorption / desorption kinetics of the alloy while improving activation properties. Scientific composition design combined with appropriate ball milling process can obtain alloy powder with special structure, thus making the alloy have excellent activation properties.

[0023] The present invention further illustrates the composition and preparation method of the high-capacity, easily activated Ti-Fe-RE-Mn-Zr-Zn-Sb-based hydrogen storage alloy through the following examples.

[0024] The high capacity and easily activated Ti-Fe-RE-Mn-Zr-Zn-Sb based hydrogen storage alloy of the present invention has the chemical formula of: Ti 1.1 Fe 0.8 Sm 0.04-x Nd x Mn 0.35-y-z-m Zr y Zn z Sb m , wherein x, y, z, and m are atomic ratios, 0.01≤x≤0.04, 0.05≤y≤0.15, 0.02≤z≤0.08, and 0.01≤m≤0.05. The preferred atomic ratio is x:y:z:m=0.02:0.12:0.04:0.03.

[0025] The preparation method of the high-capacity and easily activated Ti-Fe-RE-Mn-Zr-Zn-Sb-based hydrogen storage alloy of the present invention comprises the following steps:

[0026] A is composed of Ti according to the chemical formula 1.1 Fe 0.8 Sm 0.04-x Nd x Mn 0.35-y-z-m Zr y Zn z Sb mProceed with batching. Since Mn, Zn, Sb and rare earth elements Sm and Nd are easily volatile, a 5% burnout ratio is added during batching.

[0027] B. Place the prepared raw materials in the zirconia crucible in order. Place the pure iron rod vertically along the crucible wall. Place the block rare earth Sm and Nd at the bottom of the crucible. Place the sponge Ti and Zr on top of the rare earth Sm and Nd. Place the electrolytic Mn on top of the sponge Ti and Zr. Finally, add the metal Zn and Sb. After the materials are placed in order, cover the furnace and evacuate to 1×10 -2 -5×10 -5 After Pa, pure argon gas with a pressure of 0.01-0.1MPa is filled as a protective gas, and the melting temperature is 1500-1650℃ to obtain molten Ti 1.1 Fe 0.8 Sm 0.04-x Nd x Mn 0.35-y-z-m Zr y Zn z Sb m The liquid master alloy is kept in a molten state for 3-5 minutes, and then poured into a copper casting mold to obtain a master alloy ingot.

[0028] C will cast Ti 1.1 Fe 0.8 Sm 0.04-x Nd x Mn 0.35-y-z-m Zr y Zn z Sb m After mechanically crushing the alloy and passing it through a 200-mesh sieve, an alloy powder with a diameter of ≤75μm is obtained. This powder is then placed in a stainless steel milling jar along with stainless steel grinding balls. After evacuation, the jar is filled with high-purity argon gas and milled in an omnidirectional planetary high-energy ball mill for 0.5-2 hours at a ball-to-batch ratio of 1:20 and a rotation speed of 350 rpm. The milling time is preferably 45 minutes, resulting in the alloy powder described in the patent.

[0029] The phase structure of the as-cast and ball-milled powders was determined by XRD. The morphology and microstructure of the ball-milled alloy particles were observed using high-resolution transmission electron microscopy (HRTEM) and scanning electron microscopy (SEM). The crystalline state of the alloy was determined using selected area electron diffraction (SAED). The hydrogen absorption activation performance, hydrogen storage capacity, and hydrogen absorption and desorption kinetics of the alloy powders were determined using a semi-automatic Sieverts instrument. The hydrogen absorption temperature was 30°C and the initial hydrogen pressure was 3 MPa; the hydrogen desorption temperature was 30°C and the hydrogen desorption was carried out at 1×10 -4 Carried out under MPa pressure.

[0030] The chemical composition and proportions of the specific embodiments of the present invention are selected as follows:

[0031] Example 1: Ti 1.1 Fe 0.8 Sm 0.02 Nd 0.02 Mn 0.16 Zr 0.12 Zn 0.04 Sb 0.03

[0032] Example 2: Ti 1.1 Fe 0.8 Sm 0.03 Nd 0.01 Mn 0.16 Zr 0.12 Zn 0.04 Sb 0.03

[0033] Example 3: Ti 1.1 Fe 0.8 Sm 0.01 Nd 0.03 Mn 0.16 Zr 0.12 Zn 0.04 Sb 0.03

[0034] Example 4: Ti 1.1 Fe 0.8 Sm 0.02 Nd 0.02 Mn 0.16 Zr 0.15 Zn 0.04 Sb 0.03

[0035] Example 5: Ti 1.1 Fe 0.8 Sm 0.02 Nd 0.02 Mn 0.12 Zr 0.12 Zn 0.08 Sb 0.03

[0036] Example 6: Ti 1.1 Fe 0.8 Sm 0.02 Nd 0.02 Mn 0.14 Zr 0.12 Zn 0.04 Sb 0.05

[0037] Comparative Example 1: Ti 1.1 Fe 0.8 Mn 0.2 (Cast)

[0038] Rare earth metals Sm and Nd, sponge Ti and Zr, pure Fe, electrolytic Mn, and metallic Zn and Sb were selected according to the chemical formula composition of each embodiment. The pure iron rod was polished with sandpaper to remove the surface oxide layer. The rare earth metals Sm and Nd and electrolytic Mn, Zn, and Sb were added with a burnout amount of 5 wt.% during the batching process. The technical parameters of each stage were as follows: the vacuum induction melting furnace was evacuated to 1×10 -2 -5×10 -5 Pa; then, the furnace is filled with 0.01-0.1 MPa of inert argon as a shielding gas; the induction heating temperature is 1500-1650°C; the liquid alloy is kept molten for 3-5 minutes; the ingot alloy is mechanically crushed and passed through a 200-mesh sieve to a particle size of approximately 75 μm. The alloy powder is placed in a stainless steel mill along with stainless steel grinding balls and milled in an omnidirectional planetary ball mill for 0.5-2 hours. All process parameters can be appropriately selected within the above ranges to produce the hydrogen storage alloy powder described in the patent. Therefore, although the present invention only cites a typical embodiment, this embodiment is applicable to preparation methods with different parameters.

[0039] Process parameters of Example 1: According to the chemical formula Ti 1.1 Fe 0.8 Sm 0.02 Nd 0.02 Mn 0.16 Zr 0.12 Zn 0.04 Sb 0.03 , select bulk rare earth metals Sm and Nd, sponge Ti and Zr, pure Fe, electrolytic Mn, metallic Zn and Sb. The purity of these metals is 99.5%, and they are weighed according to the chemical dosage ratio, including 407.5 grams of sponge Ti, 84.71 grams of sponge Zr, 345.7 grams of pure iron, 24.4 grams of rare earth Sm, 23.4 grams of rare earth Nd, 71.4 grams of electrolytic Mn, 21.3 grams of metallic Zn, and 29.1 grams of metallic Sb. The weighed bulk metals are placed in the zirconia crucible of the medium frequency induction furnace according to the designed process. The pure iron rod is placed vertically along the wall of the crucible, the bulk rare earth Sm and Nd are placed at the bottom of the crucible, the sponge Ti and Zr are placed above the rare earth Sm and Nd, the electrolytic Mn is placed on the sponge Ti and Zr, and finally the metallic Zn and Sb are added. Then cover the furnace lid and evacuate for about 30 minutes to a vacuum degree of 5×10 -2 Pa, and then fill with high-purity argon protective gas until the pressure reaches -0.04MPa, adjust the heating temperature to about 1650℃, so that all the raw metals are melted, and the molten liquid metal is kept warm for 5 minutes to make it uniform. Then, the evenly mixed liquid metal is injected into a cylindrical copper mold with a diameter of 30mm and a depth of 80mm. After cooling to room temperature in the furnace, it is taken out to obtain a master alloy ingot.

[0040] Alloy Ti1.1 Fe 0.8 Sm 0.02 Nd 0.02 Mn 0.16 Zr 0.12 Zn 0.04 Sb 0.03 After the ingot was mechanically crushed and passed through a 200-mesh sieve, 20 g of the sieved alloy powder and 400 g of stainless steel grinding balls were placed in a 250 ml stainless steel ball milling jar, which was evacuated, filled with high-purity argon, and sealed. The jar was then ball milled in an omnidirectional planetary high-energy ball mill for 45 minutes.

[0041] Figure 1 The XRD patterns of the cast alloys of Examples 1 to 6 are shown below. When rare earth elements Sm, Nd, Mn, Zr, Zn, and Sb were added for alloying, it was found that the alloys had a multiphase structure, including the main phase TiFe, as well as various intermetallic compounds, ZrMn2 phases, and SbZn phases.

[0042] Figure 2 The SEM morphology of the ball-milled alloys of Examples 1-6 shows that the particles of the alloys are well dispersed after ball milling, without obvious agglomeration, which is obviously related to the short ball milling time.

[0043] Figure 3 The XRD patterns of the ball-milled alloys of Examples 1-6 show that ball milling significantly broadens the diffraction peaks of the alloys, which is obviously due to the lattice stress and grain refinement generated after ball milling.

[0044] Figure 4 HRTEM morphology of the ball-milled alloys of Examples 1-6, showing that the alloys have a nanocrystalline structure.

[0045] The hydrogen absorption activation performance, hydrogen absorption and desorption capacity and kinetics of the alloy powder were tested using a fully automatic Si everts device. The results are shown in Table 1.

[0046] Table 1 Solid-state hydrogen storage properties of alloys from different examples

[0047]

[0048] These results demonstrate that the ball-milled alloy powder exhibits excellent activation properties and high hydrogen absorption capacity. Clearly, the alloy preparation process of the present invention is simple and easy to operate, making it fully suitable for large-scale production. Its performance meets the requirements for hydrogen storage materials in various applications. Compared with similar alloys both domestically and internationally, the alloy of the present invention exhibits significantly improved hydrogen storage performance, offering distinct advantages.

[0049] This preparation method involves induction heating and melting an alloy ingot under an argon atmosphere. The alloy ingot is mechanically crushed and then subjected to short-term mechanical ball milling to obtain an alloy powder with a nanocrystalline structure. The addition of small amounts of rare earth elements Sm and Nd and metals Mn, Zr, Zn, and Sb significantly enhances the hydrogen storage and activation properties of the alloy. The rare earth elements readily form SmH3 and NdH3 during their initial hydrogen absorption, providing catalytically active centers for the alloy's activation. Mn and Zr form the intermetallic compound ZrMn2, while Zn and Sb form the SbZn phase. These compounds significantly improve the alloy's activation properties without significantly reducing its hydrogen storage capacity. Short-term ball milling significantly reduces grain size, improves the surface condition of the alloy particles, and significantly increases the crystal defect density, resulting in the alloy having excellent activation properties. Scientific composition design and the high-density dislocations formed by appropriate ball milling are key to maintaining the alloy's activation properties. Furthermore, the alloy's preparation process is easy to master and suitable for large-scale production.

[0050] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. An easily activated Ti-Fe-RE-Mn-Zr-Zn-Sb based hydrogen storage alloy, characterized in that: include: Multi-element rare earth elements Sm, Nd and transition metals Mn, Zr, Zn and Sb, whose chemical formula is: Ti 1.1 Fe 0.8 Sm 0.04-x Nd x Mn 0.35-y-z- m Zr y Zn z Sb m , where x, y, z, and m are atomic ratios, 0.01≤x≤0.04, 0.05≤y≤0.15, 0.02≤z≤0.08, 0.01≤m≤0.05; Sm and Nd form rare earth hydrides SmH3 and NdH, which become the catalytic active centers of the alloy; Zr and Mn form ZrMn2 phase, which improves the activation ability and increases the hydrogen storage capacity; the addition of Sb and Zn forms SbZn phase, which improves the activation performance of the alloy.

2. The easily activated Ti-Fe-RE-Mn-Zr-Zn-Sb based hydrogen storage alloy according to claim 1, characterized in that The atomic ratio of the chemical formula is: x: y: z: m = 0.02: 0.12: 0.04: 0.

03.

3. A method for preparing an easily activated Ti-Fe-RE-Mn-Zr-Zn-Sb based hydrogen storage alloy, characterized in that: The following steps are involved: Step 1: According to the chemical formula Ti 1.1 Fe 0.8 Sm 0.04-x Nd x Mn 0.35-y-z-m Zr y Zn z Sb m Prepare ingredients, where x, y, z, and m are atomic ratios, 0.01≤x≤0.04, 0.05≤y≤0.15, 0.02≤z≤0.08, and 0.01≤m≤0.05; Step 2: Use induction heating to melt all elements to obtain molten Ti 1.1 Fe 0.8 Sm 0.04-x Nd x Mn 0.35-y-z- m Zr y Zn z Sb m alloy; pouring the molten alloy into a copper mold to obtain a cast master alloy ingot; Step 3: Cast Ti 1.1 Fe 0.8 Sm 0.04-x Nd x Mn 0.35-y-z-m Zr y Zn z Sb m The alloy is mechanically crushed and sieved, mixed with stainless steel grinding balls and loaded into a stainless steel ball milling jar, which is then vacuumed and filled with high-purity argon gas, and ball milled in an omnidirectional planetary high-energy ball mill to obtain a ball-milled alloy.

4. The method for preparing the easily activated Ti-Fe-RE-Mn-Zr-Zn-Sb based hydrogen storage alloy according to claim 3, characterized in that: In step 1, the atomic ratio x: y: z: m = 0.02: 0.12: 0.04: 0.

03.

5. The method for preparing the easily activated Ti-Fe-RE-Mn-Zr-Zn-Sb based hydrogen storage alloy according to claim 3, characterized in that: In the step 2, the heating and melting conditions are to place the melting environment in a high-purity argon gas protection of 0.01 to 0.1 MPa.

6. The method for preparing the easily activated Ti-Fe-RE-Mn-Zr-Zn-Sb based hydrogen storage alloy according to claim 3, characterized in that: In the step 3, the mesh size of the sieve is 200 mesh, the ball milling process is 0.5-2 hours, the ball-to-material ratio is 1:20, and the rotation speed is 350 rpm.

7. The preparation method according to claim 3, characterized in that The ball-milled alloy has a nanocrystalline structure.

Images