CN-122013020-A - Preparation method of TiFe-based hydrogen storage alloy containing C

CN122013020ACN 122013020 ACN122013020 ACN 122013020ACN-122013020-A

Abstract

The invention relates to a preparation method of a TiFe-based hydrogen storage alloy containing C, which comprises the following steps of 1, weighing and mixing three raw materials of Ti, fe and C according to a preset stoichiometric ratio for forming the TiFe-based hydrogen storage alloy containing C, 2, placing the raw materials mixed in the 1 into a crucible of a vacuum arc melting furnace, sequentially carrying out rough pumping, furnace washing and vacuumizing operation, and then smelting to obtain an alloy ingot, 3, cutting the alloy ingot into thin slices, 4, carrying out heat treatment on the thin metal slices obtained by cutting in the 3, 5, polishing the thin metal slices subjected to heat treatment in the 4, carrying out physical crushing, 6, carrying out ball milling treatment on the crushed materials in the 5 to obtain metal powder, and 7, carrying out heat treatment on the metal powder obtained in the 6. The invention adds a small amount of C element into TiFe alloy to generate a second phase in the alloy, so that the hydrogen storage performance of the alloy is improved.

Inventors

LI GUANGLONG
ZHANG XIANG
GUO JINGBIN
ZHANG SIRUO
ZHANG WEI
DONG SHULIN
QU YINGDONG

Assignees

沈阳工业大学

Dates

Publication Date: 20260512
Application Date: 20251229

Claims (10)

1. The preparation method of the TiFe-based hydrogen storage alloy containing C is characterized by comprising the following steps of: step 1, weighing and mixing three raw materials Ti, fe and C according to a preset stoichiometric ratio for forming a TiFe-based hydrogen storage alloy containing C; Step 2, placing the mixed raw materials in the step 1 into a crucible of a vacuum arc melting furnace, sequentially performing rough pumping, furnace washing and vacuumizing operation, and then smelting to obtain an alloy ingot; Step 3, cutting the alloy ingot into slices; step 4, performing heat treatment on the metal sheet obtained by cutting in the step 3; Step 5, polishing the metal sheet subjected to the heat treatment in the step 4, and then physically crushing; step 6, ball milling the crushed material in the step 5 to obtain metal powder; and 7, performing heat treatment on the metal powder obtained in the step 6.
2. The method for preparing a C-containing TiFe-based hydrogen storage alloy according to claim 1, wherein the granularity of the C raw material in the step 1 is 180-200 meshes, the atomic ratio of Ti element to Fe element in a base phase of the C-containing TiFe-based hydrogen storage alloy is 1:1, the atomic ratio of the C element of the C-containing TiFe-based hydrogen storage alloy is 0-6% of the total atomic number of Ti, fe and C elements, the atomic ratio of the C element is not 0, and the chemical formula of the alloy is (TiFe) 1−x C x , wherein x is the atomic ratio coefficient of the C element, and x is 0< 0.06.
3. The method for producing a C-containing TiFe-based hydrogen storage alloy according to claim 1 or 2, wherein the raw materials in step 2 are placed in a crucible in such a manner that a Fe raw material is placed in a bottom layer, an agglomerated and wrapped C raw material is placed in a middle layer, a Ti raw material and an Fe raw material are placed in an upper layer, and the amounts of the raw materials of the respective layers are matched to the stoichiometric ratio predetermined in step 1.
4. The method for preparing a C-containing TiFe-based hydrogen storage alloy according to claim 3, wherein the agglomeration treatment of the C raw material adopts E51 epoxy resin glue to agglomerate the C raw material into spheres, and the wrapping treatment adopts metal foil to wrap the agglomerated C raw material spheres.
5. The method for preparing a TiFe-based hydrogen storage alloy containing C according to claim 1, wherein in the step 2, the smelting operation is that a plurality of times of smelting are carried out, during each time of smelting, the current is firstly increased to a first current value for melting Ti and Fe on the upper surface of the raw material and stays, then the current is increased to a second current value for melting the residual Ti and Fe, then the current is gradually increased according to a set amplitude, the current stays for a set period of time each time until the current reaches a preset third current value and stays for a set time, and finally the smelting is stopped after the current is reduced to be lower than the first current value.
6. The method for producing a C-containing TiFe-based hydrogen storage alloy according to claim 5, wherein the number of times of melting is 6, and when the 6 th time of melting is performed, electromagnetic stirring is started after all the metals in the raw materials are melted, the stirring intensity is adjusted to a predetermined range, and the electromagnetic stirring is stopped before the melting is completed.
7. The method for producing a C-containing TiFe-based hydrogen storage alloy according to claim 6, wherein the first current value is 150 to 170mA, the second current value is 250 to 270mA, the current setting amplitude is 90 to 110mA, the residence time per rise of the current is 20 to 25s, the third current value is 500 to 550mA, the duration time under the third current value is 30 to 40s, and the preset range of the electromagnetic stirring intensity is 10 to 14rpm.
8. The method for preparing the TiFe-based hydrogen storage alloy containing C according to claim 1, wherein in the step 3, an electron beam cutting mode is adopted to cut the alloy ingot into metal sheets with the thickness of 1-1.1 mm, and in the step 5, a tungsten mortar is adopted to carry out the physical crushing operation.
9. The method for preparing a TiFe-based hydrogen storage alloy containing C according to claim 1, wherein the heat treatment condition in the step 4 is that the heat preservation is carried out for 1h to 1.5h at 1373K, the metal sheet is immersed in ice brine immediately after the heat preservation is finished, and the metal sheet is taken out after being cooled to room temperature.
10. The preparation method of the TiFe-based hydrogen storage alloy containing C according to claim 1, wherein the ball milling treatment in the step 6 is forward and reverse alternate ball milling, the interval time between the forward and reverse rotations is 5-6min, absolute ethyl alcohol with the mass being 20% of the mass of materials to be ball milled is added into a ball milling tank during ball milling, argon is filled into the ball milling tank, the ball milling ball mass ratio is 40:1, molecules are the total mass of all grinding balls participating in ball milling, denominators are the total mass of materials to be ball milled after breaking in the step 5, wherein the mass of large-size grinding balls accounts for 1/4 of the total mass of all grinding balls in the grinding balls, and the heat treatment in the step 7 is carried out under the condition of heating for 1.5-2 h at 873K.

Description

Preparation method of TiFe-based hydrogen storage alloy containing C Technical Field The invention relates to the technical field of hydrogen storage materials, in particular to a preparation method of a TiFe-based hydrogen storage alloy containing C. Background Hydrogen energy is an extremely clean energy source, and the product of hydrogen combustion is mainly water, and does not generate any harmful greenhouse gases or pollutants. The energy density of hydrogen energy is very high, and the energy contained in hydrogen per unit mass is far superior to that of traditional fossil fuel. The hydrogen energy is used as a green, clean and pollution-free high-efficiency new energy source, and plays a vital role in the society with continuously increasing new energy demands. In order to effectively exploit hydrogen energy, the production, storage and transportation of hydrogen are critical issues to be addressed. The existing hydrogen storage modes mainly comprise high-pressure gas storage, ‌ low-temperature liquid hydrogen storage, metal hydride storage ‌ and the like. The metal hydride has higher mass percent density and reversibility. The maximum hydrogen absorption capacity of the TiFe-based hydrogen storage alloy material can reach 1.87wt%, and the TiFe-based hydrogen storage alloy material has the advantages of high hydrogen absorption and desorption rate, good reversibility, good circularity and low cost, but has the problem of difficult activation. Therefore, there is a need to provide a method for preparing a C-containing TiFe-based hydrogen storage alloy. Disclosure of Invention Object of the Invention In order to solve the problems in the prior art, the invention provides a preparation method of a TiFe-based hydrogen storage alloy containing C, which can be used for preparing the TiFe-based hydrogen storage alloy with low cost and good performance. In order to achieve the above purpose, the present invention provides the following technical solutions: A preparation method of a TiFe-based hydrogen storage alloy containing C comprises the following steps: step 1, weighing and mixing three raw materials Ti, fe and C according to a preset stoichiometric ratio for forming a TiFe-based hydrogen storage alloy containing C; Step 2, placing the mixed raw materials in the step 1 into a crucible of a vacuum arc melting furnace, sequentially performing rough pumping, furnace washing and vacuumizing operation, and then smelting to obtain an alloy ingot; Step 3, cutting the alloy ingot into slices; step 4, performing heat treatment on the metal sheet obtained by cutting in the step 3; Step 5, polishing the metal sheet subjected to the heat treatment in the step 4, and then physically crushing; step 6, ball milling the crushed material in the step 5 to obtain metal powder; and 7, performing heat treatment on the metal powder obtained in the step 6. As further description of the scheme, in the step 1, the granularity of the C raw material is 180-200 meshes, the atomic ratio of Ti element to Fe element in a basic phase of the C-containing TiFe-based hydrogen storage alloy is 1:1, the atomic ratio of C element of the C-containing TiFe-based hydrogen storage alloy is 0-6% of the total atomic number of Ti, fe and C elements, the atomic ratio of C element is not 0, the chemical formula of the alloy is (TiFe) 1−xCx, wherein x is the atomic ratio coefficient of C element, and x is 0< x less than or equal to 0.06. As a further description of the scheme, the raw materials in the step 2 are placed in a crucible in such a way that the Fe raw materials are placed at the bottom layer, the agglomerated and wrapped C raw materials are placed at the middle layer, the Ti raw materials and the Fe raw materials are placed at the upper layer, and the dosage of the raw materials of each layer is matched with the stoichiometric ratio preset in the step 1. As further description of the scheme, the agglomeration treatment of the C raw material adopts E51 epoxy resin glue to agglomerate the C raw material into spheres, and the wrapping treatment adopts metal foil to wrap the agglomerated C raw material spheres. In step 2, the smelting operation is that smelting is performed for multiple times, and during each smelting, the current is raised to a first current value for smelting Ti and Fe on the upper surface of the raw material and stays, then the current is raised to a second current value for smelting the residual Ti and Fe, then the current is raised gradually according to a set amplitude, the current stays for a set period every time until the current reaches a preset third current value and continues for a set period, and finally the current is reduced to be lower than the first current value and then smelting is stopped. As a further description of the above scheme, the number of smelting passes is 6, and in the 6 th smelting pass, after all the metal in the raw material is melted, electromagnetic stirring is started, the stirring inten