Porous material and apparatus, method for producing the same

Abstract

The application discloses a porous material, comprising a porous framework, which is formed by mutual adhesion of spherical or non-spherical powder particles in different broken states. The application also discloses a preparation device of the porous material, comprising a melting mechanism, an atomization mechanism and an atomization chamber which are sequentially connected in a top-down manner, wherein a deposition base is arranged in the atomization chamber, and an atomization gas outlet of the atomization mechanism is located directly above the deposition base. The porous blank with high purity, low oxygen content, high porosity and fast solidification structure can be prepared by the device. The application also discloses a preparation method of the porous material, which comprises sequentially melting, atomization deposition, sintering and machining of raw materials, so that the risk of material pollution is reduced, and the composition uniformity, porous performance and mechanical performance of the porous material are ensured.

Description

Technical Field

[0001] This invention belongs to the field of materials technology, and relates to porous materials, as well as the apparatus for preparing the aforementioned porous materials and the method for preparing the aforementioned porous materials. Background Technology

[0002] Porous materials are a type of network structure material composed of a rigid framework and internal pores. They have the characteristics of low density, high specific strength, high specific surface area, as well as good sound insulation, heat insulation, permeability, photoelectric properties, bioactivity, and adsorption properties. They are a new type of structural functional material and are widely used in aerospace, machinery, electrical appliances, medicine and other fields.

[0003] Porous materials are typically prepared using powder metallurgy, a method that uses metal powder (or a mixture of metal and non-metal powders) as raw materials, which are then shaped and sintered to obtain porous metallic materials. In the preparation of porous materials, the choice of powder and process are key factors affecting the pore structure and properties of the material. Depending on the application requirements, the alloy powder used to prepare porous materials often needs to be obtained through mechanical mixing of different powders or by crushing and ball milling alloy ingots. However, the former method makes it difficult to achieve sufficient mixing and pre-alloying of the powders, adversely affecting the uniformity of the porous material's microstructure and mechanical properties (e.g., patent "A Method for Preparing Porous Titanium-Aluminum Alloys by Powder Metallurgy", application number 201610015767.0); while the latter method can directly obtain alloyed powder, the coarse grain structure present in the original ingot is difficult to refine during ball milling, and other impurity elements are easily introduced during the ball milling process, affecting the composition and mechanical properties of the porous material. Furthermore, to ensure high porosity in porous materials, a suitable amount of pore-forming agent is typically added to the powder raw material, mixed evenly, and then pressed into a pre-form with a certain density. During the curing and sintering process, the pore-forming agent is desorbed and decomposed to obtain the porous material (e.g., patent "A Method for Preparing Porous Molybdenum Metal by Powder Metallurgy", application number 201010532845.7). While this process can achieve high material porosity, the removal of the pore-forming agent can easily lead to contamination of the furnace body and the porous material, affecting the material's performance and application range. For example, when used as a getter material for gas purification and maintaining the vacuum level inside vacuum devices in the field of vacuum technology, the release of residual additives inside the material can easily cause contamination of the purified gas and damage to the internal vacuum environment of the device, or even contamination of the entire device. Summary of the Invention

[0004] The primary objective of this invention is to provide a method for preparing porous materials, which solves the problems of poor performance of porous materials and pollution during the preparation process in the prior art.

[0005] The first technical solution adopted in this invention is a porous material preparation device, which includes a melting mechanism, an atomizing mechanism, and an atomizing chamber connected in sequence from top to bottom. A deposition substrate is provided in the atomizing chamber. The atomizing gas outlet of the atomizing mechanism is located directly above the deposition substrate. A vacuum pump is connected to the atomizing chamber. A furnace door is provided on one side of the atomizing chamber. The deposition substrate is fixed to the furnace door by a connecting mechanism.

[0006] The invention is further characterized by:

[0007] The smelting mechanism includes a smelting chamber, in which a crucible is installed, and a guide pipe is connected to the bottom of the crucible; the atomizing mechanism includes an atomizer, which is located between the atomizing chamber and the smelting chamber, and is connected to a high-pressure gas cylinder; the guide pipe extends to the high-pressure gas outlet of the atomizer, and is located directly above the deposition substrate.

[0008] The connecting mechanism includes a base, an upper connecting plate connected to the base via a lifting mechanism, a motor connected below the upper connecting plate, the motor output shaft extending out of the upper connecting plate and connecting to the deposition substrate, and the base connected to the furnace door via a connector.

[0009] The deposition matrix includes a deposition disk, which has, but is not limited to, a groove.

[0010] A second objective of this invention is to provide a method for preparing porous materials.

[0011] The second technical solution adopted in this invention is a method for preparing porous materials, using the aforementioned apparatus for preparing porous materials, comprising the following steps:

[0012] Step 1: After evacuating the melting chamber using a vacuum pump, place the prepared raw materials into a crucible and melt them to obtain molten metal.

[0013] Step 2: Transfer the molten metal liquid through the guide tube to the atomizer outlet. Adjust the deposition substrate rotation speed and deposition distance through the connecting mechanism. The high-pressure atomizing gas in the atomizer breaks the molten metal liquid flowing out of the guide tube into droplets and deposits them on the deposition substrate to obtain a porous deposition billet.

[0014] Step 3: Open the furnace door, remove the deposited substrate, and perform enhanced sintering treatment on the porous deposited billet to obtain a porous sintered billet;

[0015] Step 4: Smooth the surface of the porous sintered billet to obtain the porous material.

[0016] In step 1, the pre-evacuation vacuum degree should not be less than 5×10. -2 Pa, the melting chamber adopts a vacuum or argon atmosphere, the superheat of the molten metal during the melting process is 100-350℃, and the holding time is 5-8min.

[0017] The inner diameter of the guide tube is 1.5-4.5mm, the high-pressure atomizing gas is N2 or Ar, and the atomizing gas pressure is 2-5MPa.

[0018] In step 2, the deposition distance is not less than the deposition distance corresponding to a porous deposited blank with a porosity of 30%, and the rotation speed of the deposition substrate is 60-120 R / min.

[0019] A third objective of this invention is to provide a porous material.

[0020] The third technical solution adopted in this invention is a porous material, which is obtained by the above-mentioned porous material preparation method and includes a porous framework. The porous framework is composed of spherical or non-spherical powder particles in different broken states bonded together.

[0021] The porous framework is made of one of the following materials: titanium, titanium-molybdenum, titanium-rare earth elements, or titanium-molybdenum-rare earth elements.

[0022] The beneficial effects of this invention are as follows: The method for preparing porous materials using spray deposition technology eliminates the traditional powder metallurgy processes of powder preparation, mixing, and pressing, reducing the risk of material contamination and improving production efficiency. It is suitable for preparing atomizable metal or composite porous materials. The melting and holding process ensures thorough mixing of elements, and the high cooling rate during atomization increases the atomic solid solubility within the atomized particles, reduces elemental segregation, refines the grain structure, and ensures the uniformity of the porous material's structure and mechanical properties after deposition. The atomized material exhibits different solidification states and flight characteristics. During the deposition process, the atomized particles collide with each other and with the deposition matrix, causing varying degrees of breakage and creating gaps. The inclusion of pre-solidified small particles in the deposition layer further increases the porosity of the porous preform. Most of the powder particles in the porous preform obtained by atomization deposition have already achieved metallurgical bonding. Only a lower temperature or shorter sintering time is needed to achieve the ideal mechanical strength of the porous material, avoiding the problems of excessive grain growth and impurity element contamination caused by long-term high-temperature sintering in traditional powder sintering processes.

[0023] The porous material preparation apparatus of the present invention allows for the deposition of multiple effective deposition areas in the substrate, which can be designed and arranged according to the product shape. The resulting porous preform has a shape and size similar to the product, reducing the amount of subsequent processing and improving production efficiency and product consistency. For oversprayed powder (powder particles that do not fall into the effective deposition area), porous materials can be directly pressed and sintered to prepare porous materials, or used as raw materials for remelting, effectively avoiding waste of raw materials.

[0024] The porous material of this invention, with the addition of rare earth elements, can effectively reduce the surface tension of molten metal droplets, maintain a relatively complex solidification morphology of deposited powder particles, and improve the porosity and specific surface area of ​​the deposited preform; it can refine grains, increase grain boundary density, and create more favorable conditions for the diffusion of gas atoms in the getter material; it can purify impurities, accelerate the decomposition of oxides on the surface of the getter material, and enable the alloy to quickly exhibit a fresh metallic surface during the activation process, which is beneficial to reducing the activation temperature. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of the porous material preparation device of the present invention;

[0026] Figure 2 This is a schematic diagram of the internal connection mechanism of the porous material preparation device of the present invention;

[0027] Figure 3 This is a schematic diagram of the first structure of the deposition substrate in the porous material preparation device of the present invention;

[0028] Figure 4 This is a flowchart of the method for preparing the porous material of the present invention;

[0029] Figure 5 This is a schematic diagram of the second structure of the deposition substrate in the porous material preparation device of the present invention;

[0030] Figure 6 This is a schematic diagram of the third structure of the deposition substrate in the porous material preparation device of the present invention;

[0031] Figure 7 This is a schematic diagram of the fourth structure of the deposition substrate in the porous material preparation device of the present invention;

[0032] Figure 8 This is a microscopic morphology image of the surface of a porous deposited blank prepared by the porous material preparation method of the present invention.

[0033] In the figure, 1. Atomization chamber, 2. Deposition substrate, 201. Deposition plate, 202. Groove, 3. Vacuum pump, 4. Furnace door, 5. Melting chamber, 6. Crucible, 7. Guide pipe, 8. Atomizer, 9. High-pressure gas cylinder, 10. Base, 11. Lifting mechanism, 12. Connecting plate, 13. Motor, 14. First powder collection device, 15. Second powder collection device, 16. Connector, 17. Observation window, 18. Gas valve. Detailed Implementation

[0034] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0035] Devices for preparing porous materials, such as Figure 1As shown, the system includes a melting mechanism, an atomizing mechanism, and an atomizing chamber 1 connected sequentially from top to bottom. A deposition substrate 2 is disposed within the atomizing chamber 1. The atomized gas outlet of the atomizing mechanism is located directly above the deposition substrate 2. A vacuum pump 3 is connected to the atomizing chamber 1. A furnace door 4 is located on one side of the atomizing chamber 1, and the deposition substrate 2 is fixed to the furnace door 4 via a connecting mechanism. The atomizing chamber 1 also has an observation window 17 for easy observation of the atomization deposition process. The melting mechanism includes a melting chamber 5, within which a crucible 6 is disposed. A guide pipe 7 is connected to the bottom of the crucible 6, extending out from the atomizing mechanism. The atomizing mechanism includes an atomizer 8, located between the atomizing chamber 1 and the melting chamber 5. The atomizer 8 is connected to a high-pressure gas cylinder 9, and a gas valve 18 is installed on the pipeline between the high-pressure gas cylinder 9 and the atomizer 8. A guide pipe 7 extends to the high-pressure gas outlet of the atomizer 8, and is located directly above the deposition substrate 2. The guide pipe 7, the atomizer 8, and the deposition substrate 2 are collinear and coaxial. Preferably, the atomizer 8 is an annular or slit type. The high-pressure atomized gas ejected by the atomizer 8 breaks up and cools the liquid flowing out of the guide pipe 7. A first powder collection device 14 is provided at the bottom of the atomizing chamber 1. The atomizing chamber 1 is connected to a second powder collection device 15 via a pipeline. In this embodiment, the second powder collection device 15 is a cyclone separator. The first powder collection device 14 collects powder particles suspended in the atomizing chamber 1 during the atomization deposition process, and the second powder collection device 15 collects powder particles that settle at the bottom of the atomizing chamber 1. The oversprayed powder (powder particles that do not fall into the effective deposition area) collected by the first powder collection device 14 and the second powder collection device 15 can be directly pressed and sintered to prepare porous materials, or used as raw materials for remelting, effectively avoiding waste of raw materials.

[0036] like Figure 2 As shown, the connecting mechanism includes a base 10, on which an upper connecting plate 12 is connected via a lifting mechanism 11. A motor 13 is connected below the upper connecting plate 12, and the output shaft of the motor 13 extends out of the upper connecting plate 12 and connects to the deposition substrate 2. The base 10 is connected to the furnace door 4 via a connector 16, which can be a hollow rod or plate, allowing the connecting mechanism to be fixed to the furnace door and also providing passage for water and electricity lines. An outlet is provided on the side wall of the atomization chamber 1, and the furnace door 4 is fixed to the outlet with fasteners, such as bolts, and the deposition substrate 2 is positioned via the connecting mechanism. The lifting mechanism can be an electric telescopic rod or a cylinder, as long as it can extend and retract. The motor 13 drives the deposition substrate 2 to rotate, and the rotation speed is adjusted. The lifting mechanism 11 adjusts the deposition distance of the deposition substrate 2 by raising and lowering it.

[0037] like Figure 3As shown, the deposition substrate 2 includes a deposition disk 201, within which grooves 202 are formed. The number of grooves 202 includes, but is not limited to, one. The shape of the grooves 202 can be circular, rectangular, elliptical, heart-shaped, or annular, etc. The grooves 202 are effective deposition areas, which are areas that can limit the size and shape of the resulting porous deposited preform. When there are multiple grooves 202, they are evenly distributed on the deposition disk 201.

[0038] The method for preparing porous materials uses the aforementioned apparatus for preparing porous materials, such as... Figure 4 As shown, it includes the following steps:

[0039] Step 1: Prepare the raw materials and remove the surface oxide layer; place the prepared raw materials in the crucible 6, and use the vacuum pump 3 to evacuate the melting chamber 5, with a pre-evacuation degree of not less than 5×10⁻⁶. -2 Pa, and then heated and smelted under vacuum or argon protection to obtain molten metal liquid. During the smelting process, the superheat of the molten metal liquid is 100-350℃, and the holding time is 5-8min. The holding process can be achieved in the following ways: the transfer can be achieved by adding an intermediate crucible, that is, two crucibles are set in the smelting chamber, one is the smelting crucible, which is held at the temperature after smelting, and then transferred to the other crucible after the holding time is reached. This crucible is connected to the guide pipe 7. Alternatively, the transfer can be controlled by removing the plug, that is, during the holding time, the bottom outlet of the crucible 6 is blocked by removing the plug, and after the holding time is completed, the plug is raised away from the bottom outlet of the crucible 6.

[0040] Step 2: Transfer the molten metal liquid through the guide tube 7 to the outlet of the atomizer 8. Adjust the rotation speed and deposition distance of the deposition substrate 2 through the connecting mechanism. The deposition distance should not be less than the deposition distance corresponding to the porous deposition blank with a porosity of 30%, specifically 600-900mm. The rotation speed of the deposition substrate 2 is 60-120R / min, and the inner diameter of the guide tube 7 is 1.5-4.5mm. The molten metal liquid flowing out of the guide tube 7 is broken into droplets by the high-pressure atomizing gas in the atomizer 8 and deposited on the deposition substrate 2. The high-pressure atomizing gas is N2 or Ar, and the atomizing gas pressure is 2-5MPa, to obtain a porous deposition blank with a porosity of 30%-75%.

[0041] Step 3: Open the furnace door 4, remove the deposited substrate 2, and perform strengthening sintering treatment on the porous deposited billet. The sintering environment is a vacuum or inert gas, and the sintering temperature is 0.6-0.85T for the porous material. 熔点 The holding time is 30-90 minutes to obtain a porous sintered blank;

[0042] Step 4: Smooth the surface of the porous sintered billet to obtain the porous material.

[0043] The porous material, obtained by the above-mentioned method for preparing porous materials, includes a porous framework, which is composed of spherical or non-spherical powder particles in different broken states bonded together.

[0044] The porous material has a chemical composition of titanium (Ti), and may also include molybdenum (Mo) or auxiliary rare earth elements. The rare earth elements may be one or more of lanthanum (La), cerium (Ce), yttrium (Y), praseodymium (Pr), scandium (Sc), ytterbium (Yb), and neodymium (Nd). Specifically, it comprises the following components by mass fraction: 5–15 wt.% molybdenum, 0.5–3.5 wt.% rare earth elements, and the balance being titanium.

[0045] The concept of this invention is as follows: Traditional spray deposition technology is mainly used for the preparation of dense alloys or composite materials. To obtain high material density, a small deposition distance is often selected. However, the prepared billet inevitably contains a small number of pore defects, which need to be eliminated by means of extrusion, hot rolling, cold rolling, or hot isostatic pressing to obtain ideal microstructure and properties. Generally, when the number of pores in the material increases to a certain extent, the material will develop some special functions due to the presence of pores. This invention uses an optimized deposition distance and matches specific atomization parameters to increase the pore size of the billet to a certain extent, and then sinters the resulting porous deposited billet to obtain an ideal porous material, thus transforming the inferior pore defects in the deposited billet prepared by traditional processes into superior ones. The principle is that during the spray deposition process, the molten metal undergoes a crushing and cooling process under the action of high-pressure atomized gas. By controlling the deposition distance, the broken droplets are deposited in different solidification states, thus obtaining deposited billets with different porosities.

[0046] Given that atomization deposition technology has the characteristics of rapid solidification, it can obtain porous preforms with uniform composition, fine structure, and low impurity content, which greatly improves the mechanical, gas adsorption, and other porous properties of porous materials. In particular, the fine grain structure has a significant effect on improving the gas adsorption performance and activation temperature of gas adsorption porous materials. Therefore, the porous material preparation technology of this invention is applied to the preparation of gas-adsorbing porous materials, and titanium, an active element, is selected as the matrix material. After heating and activation (removing the surface oxide layer), the resulting porous gas-adsorbing material exhibits strong adsorption characteristics for substances such as H2, O2, N2, CO, and water vapor, and can be used for gas adsorption in the fields of vacuum maintenance and gas purification.

[0047] Through the above methods, the porous material preparation method of this invention uses jet deposition technology to prepare porous materials, eliminating the powder preparation, mixing, and pressing processes in traditional powder metallurgy, reducing the risk of material contamination, and improving production efficiency. It is suitable for preparing atomizable metal or composite porous materials. The melting and holding process ensures thorough mixing of elements, and the high cooling rate during atomization increases the atomic solid solubility of the atomized particles, reduces elemental segregation, refines the grain structure, and ensures the uniformity of the porous material's structure and mechanical properties after deposition. The atomized material exhibits different solidification states and flight speeds. During the deposition process, the atomized particles collide with each other and with the deposition matrix, causing the deposited particles to break down to varying degrees and create gaps. The inclusion of smaller, pre-solidified particles in the deposition layer further increases the porosity of the porous preform. Most of the powder particles in the porous preform obtained by atomization deposition have already achieved metallurgical bonding. Only a lower temperature or shorter sintering time is needed to achieve the ideal mechanical strength of the porous material, avoiding the problems of excessive grain growth and severe oxidation caused by long-term high-temperature sintering in traditional powder sintering processes.

[0048] The porous material preparation apparatus of the present invention allows for the deposition of multiple effective deposition areas in the substrate, which can be designed and arranged according to the product shape. The resulting porous preform has a shape and size similar to the product, reducing the amount of subsequent processing and improving production efficiency and product consistency. For oversprayed powder (powder particles that do not fall into the effective deposition area), porous materials can be directly pressed and sintered to prepare porous materials, or used as raw materials for remelting, effectively avoiding waste of raw materials.

[0049] The porous material of this invention, with the addition of rare earth elements, can effectively reduce the surface tension of molten metal droplets, maintain a relatively complex solidification morphology of deposited powder particles, and improve the porosity and specific surface area of ​​the deposited preform; it can refine grains, increase grain boundary density, and create more favorable conditions for the diffusion of gas atoms in the getter material; it can purify impurities, accelerate the decomposition of oxides on the surface of the getter material, and enable the alloy to quickly exhibit a fresh metallic surface during the activation process, which is beneficial to reducing the activation temperature.

[0050] Example 1

[0051] Step 1: Prepare Ti blocks of porous material with a chemical composition of 100 wt.% Ti, and remove the surface oxide layer; place the prepared raw material in crucible 6, and evacuate the melting chamber 5 using vacuum pump 3, with a pre-evacuation degree of not less than 5 × 10⁻⁶. -2 Pa, and then heated under vacuum to obtain molten metal liquid. During the melting process, the superheat of the molten metal liquid is 100℃, and the temperature is held for 5 minutes.

[0052] Step 2: Transfer the molten metal liquid through the guide tube 7 to the outlet of the atomizer 8. Adjust the rotation speed of the deposition substrate 2 to 120 R / min and the deposition distance to 600 mm through the connecting mechanism. During the atomization deposition process, the inner diameter of the guide tube is 1.5 mm, the high-pressure atomizing gas is Ar, and the atomizing gas pressure is 2 MPa. The deposition substrate 2 is as follows... Figure 3 As shown, the molten metal liquid is broken into droplets by the high-pressure atomizing gas in the atomizer 8 and deposited on the deposition substrate 2 to obtain a single cylindrical pure Ti porous deposition billet with a porosity of 30%.

[0053] Step 3: Open the furnace door 4, remove the deposited substrate 2, and perform enhanced sintering treatment on the porous deposited billet. The sintering environment is vacuum, and the sintering temperature is 0.6T for porous materials. 熔点 The holding time was 30 minutes to obtain a pure Ti porous sintered blank;

[0054] Step 4: The surface of the pure Ti porous sintered billet is smoothed to obtain a pure Ti type porous material with a porosity of 27%.

[0055] Example 2

[0056] Step 1: Prepare Ti and Mo blocks, the raw materials required for the porous material, according to the chemical composition Ti-5Mo, and remove the surface oxide layer; place the prepared Ti and Mo blocks in crucible 6, and evacuate the melting chamber 5 using vacuum pump 3, with a pre-evacuation degree of not less than 3×10⁻⁶. -2 Pa, and then under vacuum protection, the temperature was raised to obtain Ti-5Mo molten alloy liquid. During the melting process, the superheat of the molten alloy liquid was 150℃ and the holding time was 6min.

[0057] Step 2: Transfer the Ti-5Mo molten alloy liquid through the guide tube 7 to the outlet of the atomizer 8. Adjust the rotation speed of the deposition substrate 2 to 110 R / min and the deposition distance to 650 mm through the connecting mechanism. During the atomization deposition process, the inner diameter of the guide tube is 2 mm, the high-pressure atomizing gas is Ar, and the atomizing gas pressure is 3 MPa. The deposition substrate 2 is as follows... Figure 5 As shown, the molten metal liquid is broken into droplets by the high-pressure atomizing gas in the atomizer 8 and deposited on the deposition substrate 2 to obtain a single annular Ti-5Mo porous deposition billet with a porosity of 38%.

[0058] Step 3: Open the furnace door 4, remove the deposited substrate 2, and perform strengthening sintering treatment on the Ti-5Mo porous deposited billet. The sintering environment is vacuum, and the sintering temperature is 0.65T for porous materials. 熔点 The holding time was 45 min to obtain a Ti-5Mo porous sintered blank;

[0059] Step 4: The surface of the Ti-5Mo porous sintered billet is smoothed to obtain a Ti-5Mo porous material with a porosity of 35%.

[0060] Example 3

[0061] Step 1: Prepare Ti and La blocks (with a chemical composition of Ti-0.5La) for the porous material, and remove the surface oxide layer. Place the prepared Ti and La blocks in crucible 6, and evacuate the melting chamber 5 using vacuum pump 3. The pre-evacuation degree should not be less than 5 × 10⁻⁶. -2 Pa, and then under vacuum protection, the temperature was raised to obtain Ti-0.5La molten alloy liquid. During the melting process, the superheat of the molten alloy liquid was 200℃, and the temperature was held for 7min.

[0062] Step 2: Transfer the Ti-0.5La molten alloy liquid through the guide tube 7 to the outlet of the atomizer 8. Adjust the rotation speed of the deposition substrate 2 to 100 R / min and the deposition distance to 700 mm through the connecting mechanism. During the atomization deposition process, the inner diameter of the guide tube is 2.5 mm, the high-pressure atomizing gas is Ar, and the atomizing gas pressure is 4 MPa. The deposition substrate 2 is as follows... Figure 6 As shown, the molten metal liquid is broken into droplets by the high-pressure atomizing gas in the atomizer 8 and deposited on the deposition substrate 2 to obtain multiple cylindrical Ti-0.5La porous deposition blanks with a porosity of 46%.

[0063] Step 3: Open the furnace door 4, remove the deposited substrate 2, and perform strengthening sintering treatment on the Ti-0.5La porous deposited billet. The sintering environment is vacuum, and the sintering temperature is 0.6T for porous materials. 熔点 The holding time was 40 min to obtain a porous Ti-0.5La sintered blank;

[0064] Step 4: The surface of the Ti-0.5La porous sintered billet is machined to be flat, and Ti-0.5La porous material with a porosity of 42% is obtained.

[0065] Example 4

[0066] Step 1: Prepare Ti, Mo, and La blocks according to the chemical composition Ti-5Mo-0.5La, and remove the surface oxide layer; place the prepared Ti, Mo, and La blocks in crucible 6, and evacuate the melting chamber 5 using vacuum pump 3, with a pre-evacuation degree of not less than 3×10⁻⁶. -2 Pa, and then under vacuum protection, the temperature was raised to obtain Ti-5Mo-0.5La molten alloy liquid. During the melting process, the superheat of the molten alloy liquid was 250℃, and the temperature was held for 6 minutes.

[0067] Step 2: Transfer the Ti-5Mo-0.5La molten alloy liquid to the outlet of the atomizer 8 through the guide tube 7. Adjust the rotation speed of the deposition substrate 2 to 90 R / min and the deposition distance to 800 mm through the connecting mechanism. During the atomization deposition process, the inner diameter of the guide tube is 2.5 mm, the high-pressure atomizing gas is Ar, and the atomizing gas pressure is 3 MPa. The deposition substrate 2 is as follows... Figure 7 As shown, the molten metal liquid is broken into droplets by the high-pressure atomizing gas in the atomizer 8 and deposited on the deposition substrate 2 to obtain multiple annular Ti-5Mo-0.5La porous deposition blanks with a porosity of 57%.

[0068] Step 3: Open the furnace door 4, remove the deposited substrate 2, and perform strengthening sintering treatment on the Ti-5Mo-0.5La porous deposited billet. The sintering environment is vacuum, and the sintering temperature is 0.65T for porous materials. 熔点 The holding time was 60 min to obtain a porous Ti-5Mo-0.5La sintered blank;

[0069] Step 4: The surface of the Ti-5Mo-0.5La porous sintered billet is smoothed to obtain a Ti-5Mo-0.5La porous material with a porosity of 50%.

[0070] Example 5

[0071] Step 1: Prepare Ti, Mo, and Y blocks (with the chemical composition Ti-10Mo-1.5Y) for the porous material, and remove the surface oxide layer. Place the prepared Ti, Mo, and Y blocks in crucible 6, and evacuate the melting chamber 5 using vacuum pump 3, ensuring a pre-evacuation degree of not less than 5 × 10⁻⁶. -2 Pa, and then under vacuum protection, the temperature was raised to obtain Ti-10Mo-1.5Y molten alloy liquid. During the melting process, the superheat of the molten alloy liquid was 300℃, and the temperature was held for 7min.

[0072] Step 2: Transfer the Ti-10Mo-1.5Y molten alloy liquid to the outlet of the atomizer 8 through the guide tube 7. Adjust the rotation speed of the deposition substrate 2 to 80 R / min and the deposition distance to 850 mm through the connecting mechanism. During the atomization deposition process, the inner diameter of the guide tube is 3.5 mm, the high-pressure atomizing gas is Ar, and the atomizing gas pressure is 4 MPa. The deposition substrate 2 is as follows... Figure 6 As shown, the molten metal liquid is broken into droplets by the high-pressure atomizing gas in the atomizer 8 and deposited on the deposition substrate 2 to obtain multiple cylindrical Ti-10Mo-1.5Y porous deposition blanks with a porosity of 65%.

[0073] Step 3: Open the furnace door 4, remove the deposited substrate 2, and perform strengthening sintering treatment on the Ti-10Mo-1.5Y porous deposited billet. The sintering environment is vacuum, and the sintering temperature is 0.75T for porous materials. 熔点The holding time was 75 min to obtain a Ti-10Mo-1.5Y porous sintered blank;

[0074] Step 4: The surface of the Ti-10Mo-1.5Y porous sintered billet is smoothed to obtain Ti-10Mo-1.5Y porous material with a porosity of 58%.

[0075] Example 6

[0076] Step 1: Prepare Ti, Mo, and Ce blocks according to the chemical composition Ti-15Mo-3.5Ce, and remove the surface oxide layer; place the prepared Ti, Mo, and Ce blocks in crucible 6, and evacuate the melting chamber 5 using vacuum pump 3, with a pre-evacuation degree of not less than 1×10⁻⁶. -2 Pa, and then under vacuum protection, the temperature was raised to obtain Ti-15Mo-3.5Ce molten alloy liquid. During the melting process, the superheat of the molten alloy liquid was 350℃, and the temperature was held for 8 minutes.

[0077] Step 2: The Ti-15Mo-3.5Ce molten alloy liquid is transferred to the outlet of the atomizer 8 through the guide tube 7. The rotation speed of the deposition substrate 2 is adjusted to 70 R / min and the deposition distance to 900 mm through the connecting mechanism. During the atomization deposition process, the inner diameter of the guide tube is 4.5 mm, the high-pressure atomizing gas is Ar, and the atomizing gas pressure is 5 MPa. The deposition substrate 2 is as follows... Figure 7 As shown, the molten metal liquid is broken into droplets by the high-pressure atomizing gas in the atomizer 8 and deposited on the deposition substrate 2 to obtain multiple annular Ti-15Mo-3.5Ce porous deposition blanks with a porosity of 75%.

[0078] Step 3: Open the furnace door 4, remove the deposited substrate 2, and perform strengthening sintering treatment on the Ti-15Mo-3.5Ce porous deposited billet. The sintering environment is vacuum, and the sintering temperature is 0.85T for porous materials. 熔点 The holding time was 90 min to obtain a Ti-15Mo-3.5Ce porous sintered blank;

[0079] Step 4: The surface of the Ti-15Mo-3.5Ce porous sintered billet is smoothed to obtain a Ti-15Mo-3.5Ce porous material with a porosity of 67%.

[0080] Example 7

[0081] Step 1: Prepare Cu-B and Cu-Ti alloy blocks (with a chemical composition of Cu-2TiB2) for the porous material, and remove the surface oxide layer; place the prepared Cu-B and Cu-Ti alloy blocks in crucible 6, and evacuate the melting chamber 5 using vacuum pump 3, ensuring a pre-evacuation degree of not less than 3 × 10⁻⁶. -2Pa, and then under vacuum protection, the temperature was raised to obtain Cu-2TiB2 molten alloy liquid. During the melting process, the superheat of the molten alloy liquid was 250℃, and the temperature was held for 5min.

[0082] Step 2: Transfer the Cu-2TiB2 molten alloy liquid to the outlet of the atomizer 8 through the guide tube 7. Adjust the rotation speed of the deposition substrate 2 to 100 R / min and the deposition distance to 650 mm through the connecting mechanism. During the atomization deposition process, the inner diameter of the guide tube is 3 mm, the high-pressure atomizing gas is Ar, and the atomizing gas pressure is 3 MPa. The deposition substrate 2 is as follows... Figure 3 As shown, the molten metal liquid is broken into droplets by the high-pressure atomizing gas in the atomizer 8 and deposited on the deposition substrate 2 to obtain a single cylindrical Cu-2TiB2 porous deposition blank with a porosity of 40%.

[0083] Step 3: Open the furnace door 4, remove the deposition substrate 2, and perform strengthening sintering treatment on the Cu-2TiB2 porous deposition billet. The sintering environment is vacuum, and the sintering temperature is 0.7T for porous materials. 熔点 The holding time was 50 min to obtain Cu-2TiB2 porous sintered blank;

[0084] Step 4: The surface of the Cu-2TiB2 porous sintered billet is smoothed to obtain Cu-2TiB2 porous material with a porosity of 36%.

[0085] The tensile properties of the porous materials in Examples 1-7 were tested using a universal testing machine. Simultaneously, the gas absorption performance (dynamic constant pressure method) of the porous material samples obtained in Examples 1-6 was tested. Before testing, the samples were activated by heating in a 300℃ oven for 30 minutes. The test gas was high-purity hydrogen, and the working temperature was room temperature. The 10-minute gas absorption rate S10′ and the 240-minute gas absorption capacity Q240′ of the samples were obtained. The test results are detailed in Table 1.

[0086] Table 1 Mechanical properties and air absorption properties of porous material samples from Examples 1-7

[0087]

[0088] In summary, porous materials with different porosities can be obtained by controlling the atomization deposition and sintering processes, and different excellent porous properties can be exhibited by adjusting the chemical composition of the materials. As shown in Table 1, the porous materials prepared in Examples 1-6 have higher gas absorption rates, gas absorption capacities, and mechanical properties compared with gas-absorbing porous materials prepared by traditional processes, and have lower activation temperatures. The main reason for this is that the preparation method provided by this invention is simple and pollution-free, has the characteristics of rapid solidification technology, can achieve full solid solution of elements, reduce element segregation, refine grains, and ensure good mechanical and porosity properties of porous materials.

[0089] Figure 8 The microstructure of the porous deposited preform obtained in Example 7 shows that the material is composed of spherical or non-spherical powder particles in different fragmentation states bonded together to form a porous framework, with numerous pores distributed between and within the powder particles. As shown in Table 1, the final porous material after sintering also exhibits good mechanical properties. Example 7 further demonstrates that the method and apparatus for preparing porous materials described in this invention are not only applicable to ordinary metallic materials, but also to other atomizable composite materials besides metallic materials, and the prepared porous materials possess high porosity and mechanical properties.

Claims

1. A method for preparing porous materials, characterized in that, The apparatus for preparing porous materials includes a melting mechanism, an atomizing mechanism, and an atomizing chamber (1) connected from top to bottom. A deposition substrate (2) is provided inside the atomizing chamber (1). The atomizing gas outlet of the atomizing mechanism is located directly above the deposition substrate (2). A vacuum pump (3) is connected to the atomizing chamber (1). A furnace door (4) is provided on one side of the atomizing chamber (1). The deposition substrate (2) is fixed to the furnace door (4) by a connecting mechanism. The smelting mechanism includes a smelting chamber (5), a crucible (6) is provided inside the smelting chamber (5), and a guide pipe (7) is connected to the bottom of the crucible (6); the atomizing mechanism includes an atomizer (8), the atomizer (8) is located between the atomizing chamber (1) and the smelting chamber (5), and the atomizer (8) is connected to a high-pressure gas cylinder (9); the guide pipe (7) extends to the high-pressure gas outlet of the atomizer (8), and the guide pipe (7) is located directly above the deposition substrate (2); The connecting mechanism includes a base (10), an upper connecting plate (12) is connected to the base (10) via a lifting mechanism (11), a motor (13) is connected below the upper connecting plate (12), the output shaft of the motor (13) extends out of the upper connecting plate (12) and is connected to the deposition substrate (2), and the base (10) is connected to the furnace door (4) via a connector (16). The deposition substrate (2) includes a deposition disk (201), and the deposition disk (201) has at least one groove (202) inside. Includes the following steps: Step 1: After evacuating the melting chamber (5) by vacuum pump (3), place the prepared raw materials into the crucible (6) and melt them to obtain molten metal liquid; Step 2: Transfer the molten metal liquid through the guide pipe (7) to the outlet of the atomizer (8). Adjust the rotation speed and deposition distance of the deposition substrate (2) through the connecting mechanism. The high-pressure atomizing gas in the atomizer (8) breaks the molten metal liquid flowing out of the guide pipe (7) into droplets and deposits them on the deposition substrate (2) to obtain a porous deposition blank. Step 3: Open the furnace door (4), take out the deposition substrate (2), and perform strengthening sintering treatment on the porous deposition billet to obtain a porous sintered billet; Step 4: The surface of the porous sintered billet is smoothed to obtain a porous material; The inner diameter of the guide tube (7) is 1.5-4.5 mm, the high-pressure atomizing gas is N2 or Ar, and the atomizing gas pressure is 2-5 MPa; The deposition distance in step 2 is not less than the deposition distance corresponding to a porous deposition blank with a porosity of 30%, and the rotation speed of the deposition substrate (2) is 60-120 R / min; The porous material is one of titanium, titanium-molybdenum, titanium-rare earth elements, or titanium-molybdenum-rare earth elements.

2. The method for preparing porous materials according to claim 1, characterized in that, In step 1, the pre-vacuum degree shall not be less than 5×10⁻⁶. -2 Pa, the melting chamber (5) adopts a vacuum or argon atmosphere, the superheat of the molten metal during the melting process is 100-350℃, and the temperature is maintained for 5-8 minutes.

3. A porous material, characterized in that, The porous material is obtained by the preparation method of claim 1 or 2, and includes a porous framework, wherein the porous framework is composed of spherical or non-spherical powder particles in different broken states bonded together. The porous framework is made of one of the following materials: titanium, titanium-molybdenum, titanium-rare earth elements, or titanium-molybdenum-rare earth elements.

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