Electron beam selective melting printing porous thin-walled structure preparation method

Abstract

The application provides a preparation method of an electron beam selective melting printing porous thin-wall structure and relates to the technical field of medical bone repair. The preparation method of the electron beam selective melting printing porous thin-wall structure comprises titanium alloy powder selection, software modeling, printing parameter setting, scanning line selection, stress relief annealing heat treatment, hot isostatic pressing, acid solution treatment and zinc hydroxide aqueous solution low-temperature treatment. The preparation method can synergistically improve the formability, porosity, mechanical properties and biocompatibility of the prepared porous thin-wall structure. The thickness, porosity, strength and other properties can be customized, the resource utilization rate is high, the process is short, the efficiency is high, the product is suitable for a wide range of applications in the field of biological medicine, and the industrial large-scale production and popularization are facilitated.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical bone repair, and particularly relates to a method for preparing a porous thin-walled structure by electron beam selective melting printing. BACKGROUND

[0002] Titanium alloys are widely used in the biomedical field due to their high specific strength, high corrosion resistance and good biocompatibility. Since cell growth needs to be attached to the surface of the implant, a special structure with a high specific surface area, i.e., a porous structure, is introduced into the research of biomedical titanium alloys. Traditional methods for preparing titanium alloys can only prepare samples with regular shapes such as cylinders, while human bones and joints have more complex geometrical shapes and internal structures, which cannot be achieved by traditional preparation methods.

[0003] Additive manufacturing, a preparation method for slicing a three-dimensional CAD model layer by layer, can realize the precise printing of complex models in three-dimensional space. This process makes it possible to precisely control the complex geometry and internal microporous structure of biological structures, allowing for the free design of pore size and structure.

[0004] At present, the crystal lattice structure of different materials has been fully studied, and its formation, microstructure, mechanical properties and biological properties have been deeply studied. However, in the current study of crystal lattices, the mechanical properties mainly focus on compression performance. In terms of biological materials, the load borne by human bones includes compression load and tensile load, which is more prone to damage and destruction under tensile load. There is still less research on the relationship between the existing technology about the influence of tensile load on destruction and the porous structure, and the mechanism is not clear. In particular, although the increase of porosity in the porous structure is beneficial to the growth of human tissues after implantation, it also increases the difficulty of preparation and reduces the mechanical properties.

[0005] Therefore, how to balance the formability, porosity and mechanical properties in the preparation of titanium alloys with complex geometrical shapes and internal microporous structures is a problem to be solved.

[0006] For example: Chinese patent CN117548691A discloses a method for additive manufacturing of porous materials, which controls the lap joint rate of the molten pool to be above 80%, so that the elements inside each molten pool are fully evaporated to form pores, and a porous material is obtained. By artificially manufacturing the hole defects in the printing process, the preparation of bulk porous materials is realized; however, the defects introduced by this method are randomly distributed, and there are no channels connecting the holes, which is not suitable for application in biological materials.

[0007] Chinese patent CN118022054A discloses a personalized customized bone defect repair material and its preparation method. The method uses collagen as a framework material and decalcified bone matrix with good osteogenic performance as a hard material to enhance the mechanical support of the reinforcing material. Although this method is excellent in repairing bone defects, it has defects in mechanical properties and is difficult to meet the requirements of high mechanical properties in some scenes, such as bone support.

[0008] Chinese patent CN117883222A discloses a combined femoral stem for hip joint prosthesis and its preparation method. The method uses a forged titanium alloy plate and / or a forged cobalt-chromium alloy plate as the first raw material and is processed into a femoral stem. The porous part is made of forged titanium alloy powder and / or forged cobalt-chromium alloy powder as the second raw material and is made by 3D printing. Obviously, the manufacturing difficulty of this method is high, the process is complex, and a targeted prosthesis needs to be prepared according to the patient's bone morphology. The large pores of the porous structure on both sides have low surface area, and cells are difficult to adhere and grow.

[0009] Chinese patent CN104645419A discloses a preparation method of a porous titanium alloy femoral head support rod with bionic trabecular structure. The titanium alloy powder is Ti6Al4V or Ti2448 spherical powder. After printing, an acidic solution is needed to increase the surface roughness. Then, PLGA nanospheres, BMP-2 and VEGF complex are constructed on the surface to facilitate bone tissue ingrowth. Obviously, the biocompatibility is improved, but the relationship between the mechanism of material destruction and the porous structure and porosity is not known.

[0010] Chinese patent CN112168431A discloses a preparation method of a functional bionic porous titanium alloy femoral head support rod. The method first prints a porous titanium alloy femoral head support rod, and then prepares a high-purity magnesium coating on its inner and outer surfaces. The prepared product is not a porous thin-walled structure, and the shape, mechanical properties and specific surface area are not suitable for a porous thin-walled structure. The biocompatibility is achieved through the magnesium coating. SUMMARY

[0011] To solve the technical problems in the prior art that printing of biological materials titanium alloy can generally only prepare block porous materials, cylindrical bodies, femoral stems, bionic trabecular structure femoral head support rods and other regular shaped samples, and that the improvement of biocompatibility is achieved through coating and biological factor complex, the embodiments of the present application provide an electron beam selective melting printing porous thin-walled structure preparation method which can coordinate the formability, porosity, mechanical properties and biocompatibility of the porous thin-walled structure. The technical solution is as follows:

[0012] An electron beam selective melting printing porous thin-walled structure preparation method, which comprises the following steps:

[0013] S1, raw material selection: according to the performance requirements of the porous thin-walled structure to be prepared, the titanium alloy rotating electrode powder is selected to obtain the raw material titanium alloy powder or the raw material titanium-aluminum alloy powder;

[0014] S2, modeling: using a three-dimensional modeling software, modeling is performed according to the size of the porous thin-walled structure to be prepared, a porous thin-walled model is obtained, and the width of the molten pool and the interval of the point-shaped molten pool in the porous thin-walled model are set with corresponding parameters;

[0015] S3, printing parameter setting: the printing parameters need to be selected within the dense parameter interval of the porous thin-walled structure to be prepared, so as to print a molten pool with a relatively narrow width and a high lap joint efficiency;

[0016] S4, scanning line selection and printing: when the scanning line is selected, the point-shaped melting and jumping strategy is used; after the parameters are set and the scanning line is selected, the printing of the porous thin-walled structure is started;

[0017] S5, cutting and stress relief annealing heat treatment: after the printing is completed, the porous thin-walled sample is cut from the bottom plate using a wire cutting method, a quartz tube is used for sealing and argon is filled into the tube, and then the tube is placed in a muffle furnace for stress relief annealing heat treatment, and the furnace is heated and cooled;

[0018] S6, hot isostatic pressing: the sample after annealing is subjected to hot isostatic pressing treatment to obtain a porous thin-walled sample with enhanced powder adsorption;

[0019] S7, acid solution treatment: the porous thin-walled sample with enhanced powder adsorption is subjected to acid solution treatment, and then subjected to ultrasonic cleaning to obtain a porous thin-walled sample with increased surface roughness;

[0020] S8, zinc hydroxide aqueous solution treatment: the porous thin-walled sample with increased surface roughness is subjected to low-temperature treatment with zinc hydroxide aqueous solution, then subjected to high-temperature treatment, and finally subjected to ultrasonic cleaning and drying to obtain a final product of the porous thin-walled structure with high biocompatibility and fine zinc titanate grown on the surface.

[0021] Optionally, the particle size of the raw material titanium alloy powder in S1 is 50-200 μm, and the titanium alloy types include α-type titanium alloy and α+β dual-phase titanium alloy; the particle size of the raw material titanium-aluminum alloy powder is 50-150 μm, and the titanium-aluminum alloy types include 4822 alloy.

[0022] Optionally, the three-dimensional modeling software in S2 includes Solidworks or UG, the size range of the porous thin-walled model is 300-900 μm, the porous part is obtained by the interval of the point-shaped molten pool, the width of the molten pool in the model is 150-300 μm, the actual width of the molten pool is determined by the printing parameters, and the printing parameter interval of the porous thin-walled structure to be prepared needs to be feedback corrected.

[0023] Optionally, in S3, when the porous thin-walled structure to be prepared is TC4, the printing parameters are set to a scanning speed of 1.5-3.0 m / s, a defocus value of 50, and a current of 60-120 mA; when the porous thin-walled structure to be prepared is TA15, the printing parameters are set to a scanning speed of 1.0-2.5 m / s, a defocus value of 30, and a current of 70-130 mA; when the porous thin-walled structure to be prepared is TC11, the printing parameters are set to a scanning speed of 1.0-2.5 m / s, a defocus value of 50, and a current of 80-150 mA; and when the porous thin-walled structure to be prepared is TA17, the printing parameters are set to a scanning speed of 1.2-2.8 m / s, a defocus value of 40, and a current of 90-160 mA.

[0024] Optionally, the heating temperature of the stress-relief annealing heat treatment in S5 is 650-750℃, the heating rate with furnace is 5-10℃ / min, the holding time is 1-2h, and the cooling rate with furnace is 10-20℃ / min.

[0025] Optionally, the heating temperature of the hot isostatic pressing treatment in S6 is 850-1000℃, the gas pressure is 100-150MPa, the gas medium is argon, and the holding time is 2-4h.

[0026] Optionally, in S7, the acid solution used for acid treatment has a ratio of HF:HNO3:H2O of 1:1:2, and the treatment time is 10-30 min; the ultrasonic cleaning frequency is 20-40 Hz, and the power is 50-300 W; the thickness of the porous thin-walled sample with increased surface roughness is 100-500 μm, the porosity is 10-30%, the pore diameter is 50-200 μm, the surface roughness is Ra1-10 μm, the surface area is 200-1000 m² / m³, and the tensile strength is 100-400 MPa.

[0027] Optionally, in S8, the low-temperature treatment with zinc hydroxide aqueous solution involves immersing the porous thin-walled sample with increased surface roughness in a 0.1-0.5M zinc hydroxide aqueous solution at 20-30℃ for 1-2 hours; the high-temperature treatment involves subjecting the porous thin-walled sample with increased surface roughness after the low-temperature treatment with zinc hydroxide aqueous solution to a high-temperature treatment at 80-90℃ for 5-7 hours; the fine zinc titanate is in the shape of plate-like or columnar crystals with an average size of 1-10 μm.

[0028] Technical principle of the invention:

[0029] The present application uses three-dimensional software to draw a porous thin-walled model, imports the model into a slicing software to generate a printing model, uses printing parameters to generate a point-like narrow molten pool, and performs stress relief annealing after printing, and further increases the binding force between powders through hot isostatic pressing.

[0030] The present application uses acid solution treatment to increase the surface roughness and generate dendritic nanoscale titanium alloy on the surface, and then uses a zinc hydroxide solution for multi-step hydrothermal treatment to generate finer zinc titanate on the surface of the titanium alloy, further enhancing the contact area and biocompatibility.

[0031] The porous thin-walled structure prepared by the present application not only has an extremely small thickness, but also has excellent mesoporous characteristics and excellent mechanical properties.

[0032] The above technical solution has at least the following beneficial effects compared with the prior art:

[0033] The above scheme proposes a method for preparing a porous thin-walled structure by electron beam selective melting printing, which can solve the technical problems in the prior art that printing of titanium alloy as a biomaterial can only prepare bulk porous materials, cylindrical bodies, femoral stems, and regular-shaped samples such as bionic trabecular bone structure femoral head support rods, and that the improvement of biocompatibility is achieved through coating, biological factor complex, etc.

[0034] The porous thin-walled structure prepared by the present application has an extremely small thickness, which is 300-400 mu m at the minimum, much lower than the porous structures in other prior art, and can provide high strength and plasticity while maintaining porosity, making it more widely applicable in biomedical applications.

[0035] The porous thin-walled structure prepared by the present application has excellent mechanical properties, with a porosity of up to 30%, a pore diameter of up to 200 mu m, a surface roughness of up to Ra1, a surface area of up to 1000 m² / m³, and a tensile strength of up to 400 MPa, which can meet the high mechanical property requirements of bone fixation and repair materials.

[0036] The porosity of the porous thin-walled structure prepared by the present application is controllable in the range of 10-30%, and different porosities can be controlled by adjusting the model and printing parameters.

[0037] The porous thin-walled structure prepared by the present application can increase the surface roughness by at least 50% through acid solution treatment and zinc hydroxide solution treatment.

[0038] The present application can be bent and wrapped around various shaped bones, and since the electron beam selective melting preparation technology has small residual stress, the acid treatment and zinc hydroxide solution treatment significantly increase the surface contact area, which is very beneficial for orthopedic repair applications and has a wide application prospect.

[0039] In summary, the method of the present application, by titanium alloy powder selection, software modeling, printing parameter setting, scanning line selection, stress relief annealing heat treatment, hot isostatic pressing, acid solution treatment and low temperature treatment of zinc hydroxide aqueous solution, the forming property, porosity, mechanical property and biocompatibility of the prepared porous thin-walled structure are synergistically improved; and the thickness, porosity, strength and other properties can be customized, the resource utilization rate is high, the process is short, the efficiency is high, the product is suitable for a wide range of biological medical applications, and is conducive to industrial large-scale production and promotion. BRIEF DESCRIPTION OF DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0041] Figure 1 is a schematic diagram of the point scanning and jumping strategy in the preparation method of the porous thin-walled structure by electron beam selective melting printing of embodiment 1 of the present application;

[0042] Figure 2 is a physical diagram of measuring the thickness of the printed porous thin-walled sheet by a spiral micrometer in the preparation method of the porous thin-walled structure by electron beam selective melting printing of embodiment 1 of the present application;

[0043] Figure 3 is a physical diagram of large-angle bending of the printed porous thin-walled sheet in the preparation method of the porous thin-walled structure by electron beam selective melting printing of embodiment 1 of the present application;

[0044] Figure 4 is a physical diagram of a fractured bone model used for demonstration in the preparation method of the porous thin-walled structure by electron beam selective melting printing of embodiment 1 of the present application;

[0045] Figure 5 is a physical diagram of the fractured bone model used for demonstration using the printed porous thin-walled sheet for cladding fixation in the preparation method of the porous thin-walled structure by electron beam selective melting printing of embodiment 1 of the present application;

[0046] Figure 6 is a scanning electron microscope image of the printed porous thin-walled sheet in the preparation method of the porous thin-walled structure by electron beam selective melting printing of embodiment 2 of the present application;

[0047] Figure 7 is a porosity curve of the printed porous thin-walled sheet in the preparation method of the porous thin-walled structure by electron beam selective melting printing of embodiment 2 of the present application;

[0048] Figure 8 is a tensile specimen actual picture of a porous thin-walled piece printed in the method for preparing a porous thin-walled structure by electron beam selective melting printing according to Embodiment 3 of the present application;

[0049] Figure 9 is a fracture actual picture of a tensile specimen after printing in the method for preparing a porous thin-walled structure by electron beam selective melting printing according to Embodiment 3 of the present application;

[0050] Figure 10 is a scanning electron microscope picture of a surface after solution treatment of a porous thin-walled piece printed in the method for preparing a porous thin-walled structure by electron beam selective melting printing according to Embodiment 4 of the present application. DETAILED DESCRIPTION

[0051] The technical solutions in the present application will be described below with reference to the drawings.

[0052] In the embodiments of the present application, the words such as "example", "for example" and the like are used to represent as an example, illustration or description. Any embodiment or design scheme described as "example" in the present application should not be interpreted as more preferred or more advantageous than other embodiments or design schemes. In fact, the word "example" is intended to present the concept in a specific way. In addition, in the embodiments of the present application, the meaning expressed by "and / or" can be both, or can be one of the two.

[0053] In the embodiments of the present application, "image" and "picture" can be used interchangeably at times. It should be pointed out that the meanings expressed are consistent when the distinction is not emphasized. "The", "corresponding" and "corresponding" can be used interchangeably at times. It should be pointed out that the meanings expressed are consistent when the distinction is not emphasized.

[0054] In the embodiments of the present application, sometimes the subscript such as W1 can be written in the form of non-subscript such as W1. The meanings expressed are consistent when the distinction is not emphasized.

[0055] In order to make the technical problems, technical solutions and advantages to be solved by the present application more clear, the following will be described in detail with reference to the drawings and specific embodiments.

[0056] A method for preparing a porous thin-walled structure by electron beam selective melting printing, the method for preparing a porous thin-walled structure by electron beam selective melting printing comprising the following steps:

[0057] S1, raw material selection: according to the performance requirements of the porous thin-walled structure to be prepared, titanium alloy rotating electrode powder is selected to obtain titanium alloy powder or titanium-aluminum alloy powder as raw material;

[0058] S2, modeling: using three-dimensional modeling software to model according to the size of the porous thin-walled structure to be prepared, obtaining a porous thin-walled model, and setting corresponding parameters for the width of the molten pool and the interval of the point-like molten pool in the porous thin-walled model;

[0059] S3, printing parameter setting: the setting of printing parameters needs to be selected within the dense parameter interval of the porous thin-walled structure to be prepared, so as to print a molten pool with a relatively narrow width and high lap efficiency;

[0060] S4, scanning line selection and printing: when selecting the scanning line, the point-like melting and skipping strategy is used; after the parameters are set and the scanning line is selected, the printing of the porous thin-walled structure is started;

[0061] S5, cutting and stress relief annealing heat treatment: after printing is completed, the porous thin-walled sample is cut off from the bottom plate using a wire cutting method, sealed in a quartz tube and filled with argon, and then placed in a muffle furnace for stress relief annealing heat treatment, heated and cooled with the furnace;

[0062] S6, hot isostatic pressing: the sample after annealing is subjected to hot isostatic pressing treatment to obtain a porous thin-walled sample with enhanced powder adsorption;

[0063] S7, acid solution treatment: the porous thin-walled sample with enhanced powder adsorption is subjected to acid solution treatment, and then subjected to ultrasonic cleaning to obtain a porous thin-walled sample with increased surface roughness;

[0064] S8, zinc hydroxide aqueous solution treatment: the porous thin-walled sample with increased surface roughness is subjected to low-temperature treatment with zinc hydroxide aqueous solution, then subjected to high-temperature treatment, and finally subjected to ultrasonic cleaning and drying to obtain a final product of the porous thin-walled structure with high biocompatibility and fine zinc titanate grown on the surface.

[0065] In particular, the particle size of the raw titanium alloy powder in S1 is 50-200 μm, and the types of titanium alloy include α-type titanium alloy and α+β dual-phase titanium alloy; the particle size of the raw titanium-aluminum alloy powder is 50-150 μm, and the types of titanium-aluminum alloy include 4822 alloy.

[0066] In particular, the three-dimensional modeling software in S2 includes Solidworks or UG, and the size range of the porous thin-walled model is 300-900 μm; the porous part is obtained by the interval of the point-like molten pool, and the width of the molten pool in the model is 150-300 μm; the actual width of the molten pool is determined by the printing parameters, which need to be feedback corrected by the previous printing parameter interval of the porous thin-walled structure to be prepared.

[0067] In particular, in S3, when the porous thin-walled structure component to be prepared is TC4, the printing parameters are set as a scanning speed of 1.5-3.0 m / s, a defocusing value of 50, and a current of 60-120 mA; when the porous thin-walled structure component to be prepared is TA15, the printing parameters are set as a scanning speed of 1.0-2.5 m / s, a defocusing value of 30, and a current of 70-130 mA; when the porous thin-walled structure component to be prepared is TC11, the printing parameters are set as a scanning speed of 1.0-2.5 m / s, a defocusing value of 50, and a current of 80-150 mA; and when the porous thin-walled structure component to be prepared is TA17, the printing parameters are set as a scanning speed of 1.2-2.8 m / s, a defocusing value of 40, and a current of 90-160 mA.

[0068] In particular, in S5, the heating temperature of the stress relief annealing heat treatment is 650-750℃, the heating rate of the furnace heating is 5-10℃ / min, the holding time is 1-2h, and the cooling rate of the furnace cooling is 10-20℃ / min.

[0069] In particular, in S6, the heating temperature of the hot isostatic pressing treatment is 850-1000℃, the gas pressure is 100-150 MPa, the gas medium is argon, and the holding time is 2-4h.

[0070] In particular, in S7, the acid solution for the acid solution treatment is an acid solution with a ratio of HF:HNO3:H2O of 1:1:2, the treatment time is 10-30 min; the frequency of the ultrasonic cleaning is 20-40 Hz, and the power is 50-300 W; the thickness of the porous thin-walled sample with increased surface roughness is 100-500μm, the porosity is 10-30%, the pore diameter is 50-200μm, the surface roughness is Ra1-10μm, the surface area is 200-1000m² / m³, and the tensile strength is 100-400MPa.

[0071] In particular, in S8, the low-temperature treatment of the zinc hydroxide aqueous solution is to place the porous thin-walled sample with increased surface roughness into a 0.1-0.5M zinc hydroxide aqueous solution for low-temperature treatment at 20-30℃, and the treatment time is 1-2h; the high-temperature treatment is to perform high-temperature treatment on the porous thin-walled sample with increased surface roughness after the low-temperature treatment of the zinc hydroxide aqueous solution at 80-90℃, and the treatment time is 5-7h; and the fine zinc titanate has a shape of flaky or columnar crystals, and the average size is 1-10μm.

[0072] Example 1

[0073] A preparation method of an electron beam selective melting printing 300μm thick porous thin-walled TC4 alloy, the preparation method comprising the following steps:

[0074] S1, raw material selection: according to the performance requirements of the porous thin-walled TC4 alloy to be prepared, TC4 alloy rotating electrode powder with a particle size of 50-100 μm is selected, so as to obtain the raw material titanium alloy powder;

[0075] S2, modeling: using three-dimensional modeling software Solidworks, a model of a 300 μm thick porous thin-walled structure is obtained according to the size of the porous thin-walled TC4 alloy to be prepared, and the width of the molten pool and the interval of the point-shaped molten pool in the porous thin-walled model are set accordingly. The width of the molten pool is set to 280 μm, and the interval is set to 100 μm;

[0076] S3, printing parameter setting: the printing parameters need to be selected within the dense parameter range of the porous thin-walled structure to be prepared, including a scanning speed of 4 m / s, a defocusing value of 0, and a current of 8.5 mA, so as to print a molten pool with a relatively narrow width and high lap efficiency;

[0077] S4, scanning line selection and printing: when selecting the scanning line, a point-shaped melting and jumping strategy is used. After the parameters are set and the scanning line is selected, the printing of the porous thin-walled structure is started. The jumping strategy is short line jumping, and the schematic diagram of the jumping strategy is shown in Figure 1 ;

[0078] S5, cutting and stress relief annealing heat treatment: after printing is completed, the porous thin-walled sample is cut off from the bottom plate using a wire cutting method, and the specific physical diagram is shown in Figure 2 and Figure 3 ; the quartz tube is sealed and filled with argon, and then placed in a muffle furnace for stress relief annealing heat treatment. The heating temperature of the stress relief annealing heat treatment is 650℃, the heating rate of the furnace is 5℃ / min, the holding time is 3h, and the cooling rate of the furnace is 5℃ / min;

[0079] S6, hot isostatic pressing: the sample after annealing is subjected to hot isostatic pressing treatment. The heating temperature is 850℃, the gas pressure is 100 MPa, the gas medium is argon, and the holding time is 2h. The powder adsorption enhanced porous thin-walled sample is obtained;

[0080] S7, acid solution treatment: the powder adsorption enhanced porous thin-walled sample is subjected to acid solution treatment. The acid solution is HF:HNO3:H2O with a ratio of 2:6:92, and the treatment time is 20 min. Then, ultrasonic cleaning is performed with a frequency of 20 Hz and a power of 50 W. The porous thin-walled sample with increased surface roughness is obtained. The thickness of the porous thin-walled sample with increased surface roughness is 300 μm, the porosity is 10%, the pore diameter is 50 μm, the surface roughness is Ra2, the surface area is 200 m² / m³, and the tensile strength is 150 MPa;

[0081] S8, zinc hydroxide aqueous solution treatment: the porous thin-walled sample with increased surface roughness is treated with zinc hydroxide aqueous solution at low temperature, that is, the porous thin-walled sample with increased surface roughness is placed in 0.1M zinc hydroxide aqueous solution at 20℃ for low-temperature treatment, and the treatment time is 1h; then high-temperature treatment is performed, that is, the porous thin-walled sample with increased surface roughness after the low-temperature treatment of zinc hydroxide aqueous solution is treated at 80℃ for high-temperature treatment, and the treatment time is 5h; finally, ultrasonic cleaning is performed and then dried to obtain the final product of the porous thin-walled sample with high biocompatibility and fine zinc titanate grown on the surface.

[0082] The final product of the porous thin-walled sample with high biocompatibility and fine zinc titanate grown on the surface of the present embodiment is wrapped around a fractured bone as shown in Figure 4 , and the effect after wrapping is shown in Figure 5 . It can be seen that the porous thin-walled structure can be effectively deformed and attached to the fractured bone, and can play a good fixing role.

[0083] In the present embodiment, the fine zinc titanate has a shape of fine platelet crystals, and the average size is 3μm.

[0084] Example 2

[0085] A preparation method of electron beam selective melting printing of 350-600μm thick porous thin-walled TC4 alloy, the preparation method comprises the following steps:

[0086] S1, raw material selection: according to the performance requirements of the porous thin-walled TC4 alloy to be prepared, TC4 alloy rotating electrode powder with a powder particle size of 50-120μm is selected to obtain titanium alloy powder as raw material;

[0087] S2, modeling: using a three-dimensional modeling software Solidworks, modeling is performed according to the size of the porous thin-walled TC4 alloy to be prepared, and a plurality of porous thin-walled models with a thickness of 350-600μm are obtained, and the width of the molten pool and the interval of the point-shaped molten pool in the porous thin-walled model are set with corresponding parameters, the width of the molten pool is set to 200μm, and the interval is set to 80μm;

[0088] S3, printing parameter setting: the printing parameters need to be selected within the dense parameter range of the porous thin-walled structure to be prepared, that is, the scanning speed is 2.8m / s, the defocusing value is 0, and the current is 6.5mA, so as to print a molten pool with a relatively narrow width and high lap efficiency;

[0089] S4, scanning line selection and printing: when the scanning line is selected, a point-shaped melting and jumping strategy is used; after the parameters are set and the scanning line is selected, the printing of the porous thin-walled structure is started; wherein the jumping strategy is short line jumping, and the jumping strategy schematic diagram is shown in Figure 1 .

[0090] S5, cutting and stress relief annealing heat treatment: after printing, the porous thin-walled sample is cut from the base plate using a wire cutting method, and the surface morphology and hole characteristics are as shown in Figure 6 , the porosity is as shown in Figure 7 , the sample is sealed in a quartz tube and filled with argon, and then placed in a muffle furnace for stress relief annealing heat treatment, the heating temperature of the stress relief annealing heat treatment is 700℃, the heating rate of the furnace is 8℃ / min, the holding time is 2h, and the cooling rate of the furnace is 8℃ / min;

[0091] S6, hot isostatic pressing: the sample after annealing is subjected to hot isostatic pressing treatment, the heating temperature is 850℃, the gas pressure is 120MPa, the gas medium is argon, and the holding time is 2h, to obtain a powder adsorption enhanced porous thin-walled sample;

[0092] S7, acid solution treatment: the powder adsorption enhanced porous thin-walled sample is subjected to acid solution treatment, the acid solution is HF:HNO3:H2O in a ratio of 2:6:92, and the treatment time is 25min; then ultrasonic cleaning is performed, the frequency of ultrasonic cleaning is 40Hz, and the power is 200W; to obtain a porous thin-walled sample with increased surface roughness; the thickness of the porous thin-walled sample with increased surface roughness is 400μm, the porosity is 20%, the hole diameter is 100μm, the surface roughness is Ra4, the surface area is 500m² / m³, and the tensile strength is 500MPa;

[0093] S8, zinc hydroxide aqueous solution treatment: the porous thin-walled sample with increased surface roughness is subjected to zinc hydroxide aqueous solution low-temperature treatment, which is placing the porous thin-walled sample with increased surface roughness in 0.3M zinc hydroxide aqueous solution at 30℃ for low-temperature treatment for 1h; then high-temperature treatment is performed, which is placing the porous thin-walled sample with increased surface roughness after zinc hydroxide aqueous solution low-temperature treatment at 90℃ for high-temperature treatment for 7h; finally, ultrasonic cleaning is performed and dried, to obtain a biocompatible porous thin-walled final product with fine zinc titanate grown on the surface.

[0094] In this embodiment, the fine zinc titanate has a shape of fine platelets, and the average size is 6μm.

[0095] Example 3

[0096] A preparation method of electron beam selective melting printing of a 300μm thick porous thin-walled TA15 alloy, the preparation method comprising the following steps:

[0097] S1, raw material selection: according to the performance requirements of the porous thin-walled TA15 alloy to be prepared, TA15 alloy rotating electrode powder with a particle size of 50-100μm is selected, thereby obtaining a raw material titanium alloy powder;

[0098] S2, modeling: using three-dimensional modeling software Solidworks to model according to the size of the porous thin-walled TC4 alloy to be prepared, a 300 μm thick porous thin-walled model is obtained, and the width of the molten pool and the interval of the point-like molten pool in the porous thin-walled model are set accordingly. The width of the molten pool is set to 200 μm, and the interval is set to 60 μm;

[0099] S3, printing parameter setting: the printing parameters need to be selected within the dense parameter range of the porous thin-walled structure to be prepared, the scanning speed is 6 m / s, the defocusing value is 0, and the current is 6 mA, so as to print a molten pool with narrow width and high lap efficiency;

[0100] S4, scanning line selection and printing: when selecting the scanning line, a point-like melting and jumping strategy is used; after the parameters are set and the scanning line is selected, the printing of the porous thin-walled structure is started; wherein the jumping strategy is short line jumping, and the jumping strategy diagram is as shown in Figure 1 ;

[0101] S5, cutting and stress relief annealing heat treatment: after printing, the porous thin-walled sample is cut off from the bottom plate using a wire cutting method, and the specific physical diagram is as shown in Figure 2 and Figure 3 ; the quartz tube is sealed and filled with argon, and then placed in a muffle furnace for stress relief annealing heat treatment. The heating temperature of the stress relief annealing heat treatment is 700℃, the heating rate of the furnace is 10℃ / min, the holding time is 2h, and the cooling rate of the furnace is 10℃ / min;

[0102] S6, hot isostatic pressing: the sample after annealing is subjected to hot isostatic pressing treatment, the heating temperature is 900℃, the gas pressure is 140MPa, the gas medium is argon, and the holding time is 3h, to obtain a porous thin-walled sample with enhanced powder adsorption;

[0103] S7, acid solution treatment: the porous thin-walled sample with enhanced powder adsorption is subjected to acid solution treatment, the acid solution is HF:HNO3:H2O with a ratio of 2:6:92, and the treatment time is 30min; then ultrasonic cleaning is performed, the frequency of ultrasonic cleaning is 30Hz, and the power is 200W; a porous thin-walled sample with increased surface roughness is obtained; the thickness of the porous thin-walled sample with increased surface roughness is 290 μm, the porosity is 20%, the pore diameter is 75 μm, the surface roughness is Ra6, the surface area is 700 m² / m³, and the tensile strength is 260 MPa;

[0104] S8, zinc hydroxide aqueous solution treatment: the surface roughness increased porous thin-walled sample is treated by zinc hydroxide aqueous solution low temperature treatment, which is that the surface roughness increased porous thin-walled sample is placed in 0.2M zinc hydroxide aqueous solution 20℃ low temperature treatment, the treatment time is 1h; then high temperature treatment, the high temperature treatment is that the surface roughness increased porous thin-walled sample after zinc hydroxide aqueous solution low temperature treatment is treated at 80℃, the treatment time is 5h; finally, after ultrasonic cleaning and drying, the surface of the final product of the porous thin-walled product with high biocompatibility grows fine zinc titanate.

[0105] In this embodiment, the longer and finer zinc titanate is as shown in the figure Figure 10 The shape of the fine zinc titanate is fine flaky crystal, and the average size is 5μm.

[0106] Example 4

[0107] A preparation method of electron beam selective melting printing 500μm thick porous thin-walled TC4 alloy, the preparation method comprises the following steps:

[0108] S1, raw material selection: according to the performance requirements of the porous thin-walled TC4 alloy to be prepared, TC4 alloy rotating electrode powder with a powder particle size of 50-120μm is selected, so as to obtain the raw material titanium alloy powder;

[0109] S2, modeling: using three-dimensional modeling software Solidworks, modeling is carried out according to the size of the porous thin-walled TC4 alloy to be prepared, and a 500μm thick porous thin-walled model is obtained. The width of the molten pool and the interval of the point-like molten pool in the porous thin-walled model are set with corresponding parameters. The width of the molten pool is set to 300μm, and the interval is set to 120μm;

[0110] S3, printing parameter setting: the printing parameters need to be selected within the dense parameter range of the porous thin-walled structure to be prepared, including scanning speed 5m / s, defocusing value 0 and current 10mA, so as to print out a molten pool with narrow width and high lap efficiency;

[0111] S4, scanning line selection and printing: when selecting the scanning line, the point-like melting and skipping strategy is used; after the parameters are set and the scanning line is selected, the printing of the porous thin-walled structure is started; wherein the skipping strategy is short line skipping;

[0112] S5, cutting and stress relief annealing heat treatment: after printing, the porous thin-walled sample is cut off from the bottom plate by using wire cutting method; the quartz tube is sealed and filled with argon, and then put into the muffle furnace for stress relief annealing heat treatment. The heating temperature of the stress relief annealing heat treatment is 750℃, the heating rate of the furnace is 10℃ / min, the holding time is 2h, and the cooling rate of the furnace is 10℃ / min;

[0113] S6, hot isostatic pressing: the sample after annealing is subjected to hot isostatic pressing treatment, the heating temperature is 900℃, the gas pressure is 140MPa, the gas medium is argon, and the holding time is 2h, to obtain a porous thin-walled sample with enhanced powder adsorption;

[0114] S7, acid solution treatment: the porous thin-walled sample with enhanced powder adsorption is subjected to acid solution treatment, the acid solution is HF:HNO3:H2O in a ratio of 2:6:92, and the treatment time is 30min; then ultrasonic cleaning is performed, the frequency of ultrasonic cleaning is 40Hz, and the power is 300W; a porous thin-walled sample with increased surface roughness is obtained; the thickness of the porous thin-walled sample with increased surface roughness is 500μm, the porosity is 15%, the pore diameter is 60μm, the surface roughness is Ra10, the surface area is 1000m² / m³, and the tensile strength is 300MPa;

[0115] S8, zinc hydroxide aqueous solution treatment: the porous thin-walled sample with increased surface roughness is subjected to low-temperature treatment with zinc hydroxide aqueous solution, which is placing the porous thin-walled sample with increased surface roughness in 0.3M zinc hydroxide aqueous solution at 30℃ for low-temperature treatment for 1h; then high-temperature treatment is performed, which is subjecting the porous thin-walled sample with increased surface roughness after low-temperature treatment with zinc hydroxide aqueous solution to 90℃ high-temperature treatment for 7h; finally, ultrasonic cleaning is performed and then dried, to obtain a final product of porous thin-walled sample with high biocompatibility and surface growth of fine zinc titanate.

[0116] In this embodiment, the fine zinc titanate has a shape of fine platelets with an average size of 6μm.

[0117] Example 5

[0118] A preparation method of electron beam selective melting printing of 200μm thick porous thin-walled TC11 alloy, the preparation method comprising the following steps:

[0119] S1, raw material selection: according to the performance requirements of the porous thin-walled TC11 alloy to be prepared, TC11 alloy rotating electrode powder with a particle size of 50-120μm is selected, thereby obtaining raw titanium alloy powder;

[0120] S2, modeling: using a three-dimensional modeling software Solidworks, a model of 200μm thick porous thin-walled sample is obtained according to the size of the porous thin-walled TC11 alloy to be prepared, and the width of the molten pool and the interval of the point-like molten pool in the porous thin-walled model are set with corresponding parameters, the width of the molten pool is set to 160μm, and the interval is set to 100μm;

[0121] S3, printing parameter setting: the setting of printing parameters, the printing parameters of scanning speed 1.5 m / s, defocus value 50 and current 100 mA are selected in the density parameter interval of the porous thin-walled structure to be prepared, so as to print a molten pool with narrow width and high lap efficiency;

[0122] S4, scanning line selection and printing: in the scanning line selection, a dot melting and skipping strategy is used; after the parameter setting and the scanning line selection, the printing of the porous thin-walled structure is started; wherein the skipping strategy is short line skipping;

[0123] S5, cutting and stress relief annealing heat treatment: after the printing is completed, the porous thin-walled sample is cut off from the bottom plate by using a wire cutting method; the quartz tube is used for sealing and filling argon gas into the tube, and then it is placed in a muffle furnace for stress relief annealing heat treatment, the heating temperature of the stress relief annealing heat treatment is 680℃, the heating rate of the furnace is 6℃ / min, the holding time is 2.5h, and the cooling rate of the furnace is 6℃ / min;

[0124] S6, hot isostatic pressing: the sample after annealing is treated by hot isostatic pressing, the heating temperature is 900℃, the gas pressure is 140MPa, the gas medium is argon, and the holding time is 3.5h;

[0125] S7, acid solution treatment: the porous thin-walled sample with enhanced powder adsorption is treated by acid solution, the ratio of HF:HNO3:H2O is 2:6:92, and the treatment time is 15min; then ultrasonic cleaning is carried out, the frequency of ultrasonic cleaning is 25Hz, and the power is 60W; the porous thin-walled sample with increased surface roughness is obtained; the thickness of the porous thin-walled sample with increased surface roughness is 190μm, the porosity is 18%, the pore diameter is 80μm, the surface roughness is Ra7, the surface area is 450 m² / m³, and the tensile strength is 180MPa;

[0126] S8, zinc hydroxide aqueous solution treatment: the porous thin-walled sample with increased surface roughness is treated by zinc hydroxide aqueous solution at low temperature, which is to place the porous thin-walled sample with increased surface roughness in 0.25M zinc hydroxide aqueous solution at 30℃ for low temperature treatment, and the treatment time is 1.5h; then high temperature treatment is carried out, which is to treat the porous thin-walled sample with increased surface roughness after the low temperature treatment of zinc hydroxide aqueous solution at 90℃ for 5h; finally, ultrasonic cleaning and drying are carried out, and the final product of the porous thin-walled structure with high biocompatibility and fine zinc titanate growth on the surface is obtained.

[0127] In this embodiment, the fine zinc titanate has a shape of fine flake, and the average size is 8μm.

[0128] Example 6

[0129] A method for preparing a 420 μm thick porous thin-walled 4822 alloy by electron beam selective melting, the method comprising the following steps:

[0130] S1, raw material selection: according to the performance requirements of the porous thin-walled 4822 alloy to be prepared, TA17 alloy rotating electrode powder with a particle size of 50-150 μm is selected, thereby obtaining the raw material titanium-aluminum alloy powder;

[0131] S2, modeling: using a three-dimensional modeling software Solidworks, a model of a 420 μm thick porous thin-walled structure is obtained according to the size of the porous thin-walled TA17 alloy to be prepared, and the width of the molten pool and the interval of the point-shaped molten pool in the porous thin-walled model are set with corresponding parameters, the width of the molten pool is set to 180 μm, and the interval is set to 150 μm;

[0132] S3, printing parameter setting: the printing parameters need to be selected within the dense parameter range of the porous thin-walled structure to be prepared, including a scanning speed of 2.6 m / s, a defocusing value of 40, and a current of 150 mA, so as to print a molten pool with a relatively narrow width and high lap efficiency;

[0133] S4, scanning line selection and printing: when the scanning line is selected, a point-shaped melting and skipping strategy is used; after the parameters are set and the scanning line is selected, the printing of the porous thin-walled structure is started; wherein the skipping strategy is short line skipping;

[0134] S5, cutting and stress relief annealing heat treatment: after the printing is completed, the porous thin-walled sample is cut off from the bottom plate using a wire cutting method; the sample is sealed in a quartz tube and filled with argon, and then placed in a muffle furnace for stress relief annealing heat treatment, the heating temperature of the stress relief annealing heat treatment is 720 ℃, the heating rate of the furnace is 8 ℃ / min, the holding time is 2 h, and the cooling rate of the furnace is 8 ℃ / min;

[0135] S6, hot isostatic pressing: the sample after annealing is subjected to hot isostatic pressing treatment, the heating temperature is 900 ℃, the gas pressure is 120 MPa, the gas medium is argon, and the holding time is 2.5 h, thereby obtaining a powder adsorption enhanced porous thin-walled sample;

[0136] S7, acid solution treatment: the powder adsorption enhanced porous thin-walled sample is subjected to acid solution treatment, the acid solution is HF:HNO3:H2O with a ratio of 2:6:92, and the treatment time is 20 min; then ultrasonic cleaning is performed, the frequency of the ultrasonic cleaning is 30 Hz, and the power is 300 W; thereby obtaining a porous thin-walled sample with increased surface roughness; the thickness of the porous thin-walled sample with increased surface roughness is 410 μm, the porosity is 15%, the pore diameter is 80 μm, the surface roughness is Ra9, the surface area is 500 m² / m³, and the tensile strength is 300 MPa;

[0137] S8, zinc hydroxide aqueous solution treatment: the surface roughness increased porous thin wall sample is treated by zinc hydroxide aqueous solution low temperature, which is that the surface roughness increased porous thin wall sample is placed in 0.3M zinc hydroxide aqueous solution 25℃ low temperature treatment, and the treatment time is 1h;Then high temperature treatment, high temperature treatment is that the surface roughness increased porous thin wall sample after zinc hydroxide aqueous solution low temperature treatment is treated at 85℃, and the treatment time is 6h;Finally, after ultrasonic cleaning and drying, the surface growth fine zinc titanate is obtained. The final product of the porous thin wall with high biocompatibility.

[0138] In the embodiment, the fine zinc titanate is in the form of fine flake, and the average size is 8μm.

[0139] The above scheme, the present application provides a kind of electron beam selective melting printing porous thin wall structure preparation method, can solve the technical problems in prior art, such as printing biomaterial titanium alloy generally only preparing block porous material, cylinder, femoral stem, bionic trabecular bone structure femoral head support stick etc. Regular shape sample, the improvement of biocompatibility is through coating, biological factor complex etc.

[0140] The thickness of the porous thin wall structure prepared by the present application is extremely thin, reaching 300-400μm at the minimum, which is much lower than the porous structure in other prior art, and can provide high strength and plasticity while maintaining porosity, making it more widely applicable in biomedical applications.

[0141] The porous thin wall structure prepared by the present application has excellent mechanical properties, with a porosity of up to 30%, a pore diameter of up to 200μm, a surface roughness of up to Ra1, a surface area of up to 1000m² / m³, and a tensile strength of up to 400MPa, which can meet the higher mechanical property requirements of bone fixation and repair materials.

[0142] The porosity of the porous thin wall structure prepared by the present application can be controlled in the range of 10-30%, and different porosities can be controlled by adjusting the model and printing parameters.

[0143] The porous thin wall structure prepared by the present application can increase the surface roughness by at least 50% through acid solution treatment and zinc hydroxide solution treatment.

[0144] In summary, compared with other conventional methods, the method of the present application can synergistically improve the formability, porosity, mechanical properties and biocompatibility of the prepared porous thin-walled structure by selecting titanium alloy powder, software modeling, printing parameter setting, scanning line selection, stress relief annealing heat treatment, hot isostatic pressing, acid solution treatment and low-temperature treatment with zinc hydroxide aqueous solution; and the thickness, porosity, strength and other properties can be customized, the resource utilization rate is high, the process is short, the efficiency is high, the product is suitable for a wide range of biological medical applications, and it is beneficial to industrial large-scale production and promotion.

[0145] It should be understood that the term "and / or" herein merely describes an association relationship of associated objects, and means that there can be three relationships, for example, A and / or B can mean that A exists alone, A and B exist together, and B exists alone, wherein A and B can be singular or plural. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after it, but it can also represent an "and / or" relationship, which can be understood according to the context before and after it.

[0146] In the present application, "at least one" means one or more, and "multiple" means two or more. "At least one of the following" or the like means any combination of these items, including any combination of single item or multiple items. For example, at least one of a, b, or c can mean a, b, c, a-b, a-c, b-c, or a-b-c, wherein a, b, and c can be single or multiple.

[0147] It should be understood that in various embodiments of the present application, the size of the sequence number of the above-mentioned processes does not mean the order of execution, and the execution order of the processes should be determined according to their functions and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0148] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto, and any skilled person in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for manufacturing a porous thin-walled structure by electron beam selective melting printing, characterized in that, The electron beam selective melting printing porous thin-walled structure preparation method comprises the following steps: S1, raw material selection: according to the performance requirements of the porous thin-walled structure to be prepared, titanium alloy rotating electrode powder is selected to obtain raw material titanium alloy powder or raw material titanium-aluminum alloy powder; S2, modeling: using a three-dimensional modeling software, a model is established according to the size of the porous thin-walled structure to be prepared, a porous thin-walled model is obtained, and the width of the molten pool and the interval of the point-shaped molten pool in the porous thin-walled model are set correspondingly; S3, printing parameter setting: the printing parameters need to be selected within the dense parameter interval of the porous thin-walled structure to be prepared, so as to print a molten pool with a relatively narrow width and a high lap joint efficiency; S4, scanning line selection and printing: when the scanning line is selected, a point-shaped melting and jumping strategy is used; After the parameters are set and the scanning line is selected, the printing of the porous thin-walled structure is started; S5, cutting and stress relief annealing heat treatment: after printing, the porous thin-walled sample is cut off from the bottom plate by using a wire cutting method, a quartz tube is used for sealing and argon gas is filled into the tube, and then the tube is placed in a muffle furnace for stress relief annealing heat treatment, and the furnace is heated and cooled; S6, hot isostatic pressing: the sample after annealing is subjected to hot isostatic pressing treatment to obtain a porous thin-walled sample with enhanced powder adsorption; S7, acid solution treatment: the porous thin-walled sample with enhanced powder adsorption is subjected to acid solution treatment, and then subjected to ultrasonic cleaning to obtain a porous thin-walled sample with increased surface roughness; S8, zinc hydroxide aqueous solution treatment: the porous thin-walled sample with increased surface roughness is subjected to low-temperature treatment with zinc hydroxide aqueous solution, and then subjected to high-temperature treatment, and finally subjected to ultrasonic cleaning and drying to obtain a final product of the porous thin-walled structure with high biocompatibility and fine zinc titanate grown on the surface.

2. The method of claim 1, wherein the method further comprises: In S1, the particle size of the raw material titanium alloy powder is 50-200 μm, and the titanium alloy types include α-type titanium alloy and α+β dual-phase titanium alloy; the particle size of the raw material titanium-aluminum alloy powder is 50-150 μm, and the titanium-aluminum alloy types include 4822 alloy.

3. The method of claim 1, wherein the method further comprises: In S2, the three-dimensional modeling software includes Solidworks or UG, the size range of the porous thin-walled model is 300-900 μm, the porous part is obtained by the interval of the point-shaped molten pool, the width of the molten pool in the model is 150-300 μm, and the actual width of the molten pool is determined by the printing parameters, which need to be feedback corrected by the previous printing parameter interval of the porous thin-walled structure to be prepared.

4. The method of claim 1, wherein the method further comprises: In S3, when the porous thin-walled structure component to be prepared is TC4, the printing parameters are set as a scanning speed of 1.5-3.0 m / s, a defocus value of 50, and a current of 60-120 mA; when the porous thin-walled structure component to be prepared is TA15, the printing parameters are set as a scanning speed of 1.0-2.5 m / s, a defocus value of 30, and a current of 70-130 mA; when the porous thin-walled structure component to be prepared is TC11, the printing parameters are set as a scanning speed of 1.0-2.5 m / s, a defocus value of 50, and a current of 80-150 mA; and when the porous thin-walled structure component to be prepared is TA17, the printing parameters are set as a scanning speed of 1.2-2.8 m / s, a defocus value of 40, and a current of 90-160 mA.

5. The method of claim 1, wherein the method further comprises: In S4, the jump strategy is short-line jumping.

6. The method of claim 1, wherein the method further comprises: In S5, the heating temperature of the stress relief annealing heat treatment is 650-750℃, the heating rate of the furnace heating is 5-10℃ / min, the holding time is 1-2 h, and the cooling rate of the furnace cooling is 10-20℃ / min.

7. The method of claim 1, wherein the method further comprises: In S6, the heating temperature of the hot isostatic pressing treatment is 850-1000℃, the gas pressure is 100-150 MPa, the gas medium is argon, and the holding time is 2-4 h.

8. The method of claim 1, wherein the method further comprises: In S7, the acid solution is HF:HNO3:H2O with a ratio of 1:1:2, the treatment time is 10-30 min, the frequency of the ultrasonic cleaning is 20-40 Hz, the power is 50-300 W, the thickness of the porous thin-walled sample with increased surface roughness is 100-500 μm, the porosity is 10-30%, the pore diameter is 50-200 μm, the surface roughness is Ra1-10 μm, the surface area is 200-1000 m² / m³, and the tensile strength is 100-400 MPa.

9. The method of claim 1, wherein the method further comprises: In S8, the low-temperature treatment of the zinc hydroxide aqueous solution is to place the porous thin-walled sample with increased surface roughness into a 0.1-0.5 M zinc hydroxide aqueous solution at 20-30℃ for 1-2 h, the high-temperature treatment is to perform 80-90℃ high-temperature treatment on the porous thin-walled sample with increased surface roughness after the low-temperature treatment of the zinc hydroxide aqueous solution for 5-7 h, the fine zinc titanate has a shape of flaky or columnar crystal, and the average size is 1-10 μm.

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