Titanium-chromium-based hydrogen storage alloy and preparation method thereof

Abstract

The invention relates to the technical field of hydrogen storage materials, in particular to a titanium-chromium-based hydrogen storage alloy and a preparation method thereof.The general formula of the titanium-chromium-based hydrogen storage alloy is (TixZr1-x) CryM2-y, and x is larger than 0 and smaller than or equal to 0.9; x is larger than or equal to 1.5 and smaller than 2, y is larger than or equal to 1.5 and smaller than 2, and M comprises at least one of Mn, Co, Fe, V, Si and Ni. According to the titanium-chromium-based hydrogen storage alloy, the hydrogen storage capacity and activation performance of the titanium-chromium-based hydrogen storage alloy are improved, meanwhile, the platform pressure of hydrogen absorption and desorption and the hysteresis effect are improved, in addition, the preparation method of the titanium-chromium-based hydrogen storage alloy is further provided, and through laser additive manufacturing, stress relief annealing and enhancement of the diffusion process of hydrogen in metal, the performance of the titanium-chromium-based hydrogen storage alloy is improved. The hydrogen storage performance of the alloy is obviously improved.

Description

Technical Field

[0001] The invention relates to the technical field of hydrogen storage materials, and in particular to a titanium-chromium-based hydrogen storage alloy and a preparation method thereof. Background Art

[0002] Titanium-based hydrogen storage alloys have the advantages of low cost, simple alloy design, and can be used under normal temperature and pressure. At the same time, they have the disadvantages of difficulty in activation, easy poisoning, and severe hysteresis. Titanium-based hydrogen storage alloys are mainly divided into three series: titanium-iron-based hydrogen storage alloys, titanium-chromium-based hydrogen storage alloys, and titanium-manganese-based hydrogen storage alloys. Among them, titanium-iron-based alloys are difficult to activate, and titanium-manganese-based alloys have poor resistance to gas poisoning, while titanium-chromium-based alloys are easy to activate and have a higher hydrogen storage density. At the same time, the chromium element can enhance its anti-poisoning performance. However, titanium-chromium-based alloys still have the disadvantages of high hydrogen absorption and desorption platform pressure and severe hysteresis, so it is necessary to further improve their hydrogen storage performance through reasonable composition design.

[0003] Laser additive manufacturing technology has the advantages of fast near-net shaping, high flexibility, and no need for a large amount of subsequent machining. Its extremely high temperature gradient and ultra-fast cooling rate can effectively refine the grains. Compared with the traditional vacuum induction melting method for preparing hydrogen storage alloys, laser additive manufacturing technology has a fast cooling rate and can significantly refine the grain boundaries, which is conducive to the diffusion of hydrogen through the grain boundaries and increases the hydrogen storage performance of the material.

[0004] In the process of using laser additive manufacturing technology to prepare titanium-chromium-based hydrogen storage materials, although introducing a certain amount of reinforcement phase by mixing powders can refine the grains and eliminate the coarse columnar crystal texture, the melting and solidification process of additive manufacturing is accompanied by rapid temperature changes, and the inside of the sample is prone to uneven plastic deformation caused by thermal expansion and contraction or solid phase change, so there is often a large residual stress, resulting in macro cracking and other phenomena. Therefore, it is also necessary to reduce the residual stress by introducing stress relief annealing, while reducing the resistance of hydrogen diffusion in the alloy structure. Summary of the invention

[0005] In order to solve the above technical problems, the embodiments of the present invention provide a titanium-chromium-based hydrogen storage alloy and a preparation method thereof, which improve the hydrogen storage capacity and activation performance of the titanium-chromium-based hydrogen storage alloy, while improving the platform pressure and hysteresis effect of hydrogen absorption and desorption. In addition, a preparation method of a titanium-chromium-based hydrogen storage alloy is provided, which enhances the diffusion process of hydrogen in the metal through laser additive manufacturing and stress relief annealing, thereby significantly improving the hydrogen storage performance of the alloy.

[0006] To achieve the above object, the embodiments of the present invention adopt the following technical solutions:

[0007] On the one hand, the present invention provides a titanium-chromium-based hydrogen storage alloy, the general formula of which is: (TixZr1-x)CryM2-y, wherein 0<x≤0.9; 1.5≤y<2, and M includes at least one of Mn, Co, Fe, V, Si and Ni.

[0008] In some embodiments, the Fe element is derived from an iron-vanadium alloy having an iron-vanadium mass ratio of 0.92-1.08.

[0009] In some embodiments, the V element is derived from an iron-vanadium alloy having an iron-vanadium mass ratio between 0.92 and 1.08.

[0010] In some embodiments, the titanium-chromium-based hydrogen storage alloy is composed of Ti 0.9 Zr 0.1 Cr 1.6 Mn 0.2 Fe 0.1 V 0.1 .

[0011] In some embodiments, the titanium-chromium-based hydrogen storage alloy is composed of Ti 0.9 Zr 0.1 Cr 1.5 Mn 0.2 Fe 0.2 V 0.1 .

[0012] In some embodiments, the titanium-chromium-based hydrogen storage alloy is composed of Ti 0.9 Zr 0.1 Cr 1.4 Mn 0.2 F e0.2 V 0.2 .

[0013] In another aspect, the present invention provides a method for preparing a titanium-chromium-based hydrogen storage alloy, comprising the following steps:

[0014] The titanium-chromium-based hydrogen storage alloy is obtained by mixing the metal raw materials according to their contents, atomizing them through vacuum gas, and then 3D printing, stress annealing and crushing them through laser melting deposition equipment.

[0015] In some embodiments, the alloy powder obtained by vacuum gas atomization has a particle size of 15 to 150 μm.

[0016] In some embodiments, the parameters of the laser melting deposition 3D printing are laser power 800-1200W, scanning speed 600-1000mm / min, scanning spacing 1-3mm, and layer height 0.2-0.5mm.

[0017] In some embodiments, the stress annealing treatment has an annealing heating rate of 10°C / min, a holding temperature of 400-600°C, argon protection is introduced during the holding process, the holding time is 1-4h, and the cooling medium is air.

[0018] In some embodiments, the particle size of the titanium-chromium-based hydrogen storage alloy obtained by crushing is 1-3 mm.

[0019] Compared with the prior art, the present invention has at least the following beneficial effects:

[0020] By adjusting the content of Ti-Zr-Cr-Mn-Fe-V elements, the hydrogen storage capacity and activation performance of titanium-chromium-based hydrogen storage alloys are significantly improved, while the platform pressure and hysteresis effect of hydrogen absorption and desorption are improved. In addition, laser additive manufacturing and stress relief annealing are used to enhance the diffusion process of hydrogen in the metal, significantly improving the hydrogen storage performance of the alloy.

[0021] The present invention adds Zr elements with a larger atomic radius to partially replace Ti in TiCr2 alloy, which can increase the unit cell volume of the alloy; after the lattice constant increases, the lattice gap that can accommodate hydrogen atoms in the alloy increases, thereby effectively improving the activation performance of the alloy, increasing the amount of hydrogen absorption, and reducing the reversible hydrogen storage capacity. Adding a small amount of Fe to replace Cr can increase the hydrogen absorption platform pressure and reversible hydrogen storage capacity of the alloy, reduce the hydrogen release enthalpy change, and increase the release temperature of residual hydrogen. Fe atoms improve the hydrogen absorption kinetics of the alloy by adjusting the interaction between hydrogen and other atoms, reduce the hysteresis effect of hydrogen absorption and desorption of the alloy, and enhance the activation performance. After adding V to replace part of Cr, the unit cell parameters of the alloy increase, the amount of hydrogen absorption increases, the hysteresis effect in the hydrogen absorption and desorption process increases, and the hydrogen absorption and desorption platform pressure decreases. Adding a certain amount of Mn element, as the Mn content increases, the initial activation performance of the Ti-Cr alloy is improved due to the appearance of a new phase, and the hydrogen absorption and desorption platform pressure and hysteresis effect are reduced.

[0022] The present invention uses laser additive manufacturing technology to prepare hydrogen storage alloys. During the preparation process, laser additive manufacturing has a fast cooling speed, which can significantly refine the grain boundaries, facilitate the diffusion of hydrogen through the grain boundaries, and increase the hydrogen storage performance of the material. At the same time, stress relief annealing is introduced to reduce the residual stress generated during the laser additive manufacturing process, thereby reducing the resistance to hydrogen diffusion in the alloy structure and improving the hydrogen storage performance of the alloy. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a scanning electron microscope image of the powder of the titanium-chromium-based hydrogen storage alloy after ball milling in Example 1 of the present invention. DETAILED DESCRIPTION

[0024] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in some embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments provided by the present disclosure, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present disclosure.

[0025] Example 1

[0026] The metal raw materials are mixed according to the content of the titanium-chromium-based hydrogen storage alloy, and a chemical formula of Ti is prepared by vacuum gas atomization. 0.9 Zr 0.1 Cr 1.6 Mn 0.2 Fe 0.1 V 0.1 The alloy powder particle size is 30μm, and it is additively manufactured by laser melting deposition 3D printing equipment. The laser melting deposition additive manufacturing parameters are as follows: laser power 900W, scanning speed 600mm / min, scanning spacing 1mm, layer height 0.2mm. The printed additively manufactured titanium-chromium-based alloy is kept in a resistance heating furnace set at a furnace temperature of 400℃ for 2h for stress relief annealing, and then cooled to room temperature with the furnace. The cooled alloy is crushed into powder material, and hydrogen charging test is carried out to detect the hydrogen storage performance of the alloy.

[0027] Example 2

[0028] The metal raw materials are mixed according to the content of the titanium-chromium-based hydrogen storage alloy, and a chemical formula of Ti is prepared by vacuum gas atomization. 0.9 Zr 0.1 Cr 1.5 Mn 0.2 Fe 0.2 V 0.1 The alloy powder particle size is 50μm, and it is additively manufactured using a laser melting deposition 3D printing device. The laser melting deposition additive manufacturing parameters are as follows: laser power 900W, scanning speed 600mm / min, scanning spacing 1mm, layer height 0.2mm. The printed additively manufactured titanium-chromium-based alloy is kept in a resistance heating furnace set at a furnace temperature of 500℃ for 2.5h for stress relief annealing, and then cooled to room temperature with the furnace. The cooled alloy is crushed into powder material, and a hydrogen charging test is carried out to detect the hydrogen storage performance of the alloy.

[0029] Example 3

[0030] The metal raw materials are mixed according to the content of the titanium-chromium-based hydrogen storage alloy, and a chemical formula of Ti is prepared by vacuum gas atomization. 0.9 Zr 0.1 Cr 1.4 Mn 0.2 F e0.2 V0.2 The alloy powder particle size is 100μm, and it is additively manufactured using a laser melting deposition 3D printing device. The laser melting deposition additive manufacturing parameters are as follows: laser power 900W, scanning speed 600mm / min, scanning spacing 1mm, layer height 0.2mm. The printed additively manufactured titanium-chromium-based alloy is kept in a resistance heating furnace set at a furnace temperature of 600℃ for 3h for stress relief annealing, and then cooled to room temperature with the furnace. The cooled alloy is crushed into powder material, and a hydrogen charging test is carried out to detect the hydrogen storage performance of the alloy.

[0031] The gaseous hydrogen absorption and desorption capacity and kinetics of the alloy were tested, and the results are shown in Table 1.

[0032] Table 1 Hydrogen storage capacity and cycle stability of hydrogen storage alloys with different alloy powder compositions

[0033]

[0034]

[0035] — Hydrogen absorption within 5 minutes at an initial hydrogen pressure of 3.5 MPa and 300 K (wt.%);

[0036] —At an initial pressure of 1×10 -4 MPa and 300K, the amount of hydrogen released within 30 minutes (wt.%); S 100 =C 100 / C max × 100%, where C max is the saturated hydrogen absorption capacity of the alloy, C 100 is the amount of hydrogen absorbed after the 100th cycle.

[0037] The results in Table 1 show that the alloy powder proposed in the present invention has a high hydrogen absorption and desorption capacity and excellent dynamic performance. Compared with similar alloys studied at home and abroad, the hydrogen storage performance of the alloy of the present invention at low temperature has been significantly improved, and the alloy has good hydrogen absorption and desorption cycle stability.

[0038] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0039] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A titanium-chromium-based hydrogen storage alloy, characterized in that: The general formula of the titanium-chromium-based hydrogen storage alloy is: x Zr 1-x )Cr y M 2-y , wherein 0<x≤0.9; 1.5≤y<2, and M includes at least one of Mn, Co, Fe, V, Si and Ni.

2. A titanium-chromium-based hydrogen storage alloy according to claim 1, characterized in that: The titanium-chromium-based hydrogen storage alloy comprises Ti 0.9 Zr 0.1 Cr 1.6 Mn 0.2 Fe 0.1 V 0.1 .

3. A titanium-chromium-based hydrogen storage alloy according to claim 1, characterized in that: The titanium-chromium-based hydrogen storage alloy comprises Ti 0.9 Zr 0.1 Cr 1.5 Mn 0.2 Fe 0.2 V 0.1 .

4. The titanium-chromium-based hydrogen storage alloy according to claim 1, characterized in that: The titanium-chromium-based hydrogen storage alloy comprises Ti 0.9 Zr 0.1 Cr 1.4 Mn 0.2 F e0.2 V 0.2 .

5. A method for preparing a titanium-chromium-based hydrogen storage alloy as claimed in any one of claims 1 to 4, characterized in that: The following steps are involved: The titanium-chromium-based hydrogen storage alloy is obtained by mixing the metal raw materials according to their contents, atomizing them through vacuum gas, and then 3D printing, stress annealing and crushing them through laser melting deposition equipment.

6. The preparation method according to claim 5, characterized in that: The alloy powder obtained by vacuum gas atomization has a particle size of 15 to 150 μm.

7. The preparation method according to claim 5, characterized in that: The parameters of the laser melting deposition 3D printing are laser power 800-1200W, scanning speed 600-1000mm / min, scanning spacing 1-3mm, and layer height 0.2-0.5mm.

8. The preparation method according to claim 5, characterized in that: The stress annealing treatment has an annealing heating rate of 10°C / min, a holding temperature of 400-600°C, argon protection during the holding process, a holding time of 1-4h, and air as the cooling medium.

9. The preparation method according to claim 5, characterized in that: The particle size of the titanium-chromium-based hydrogen storage alloy obtained by the crushing is 1-3 mm.

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