Digital light processing 3D printing alloy general resin and porous alloy preparation method

Abstract

The application discloses a kind of digital light processing 3D printing alloy general resin and the preparation method of porous alloy, belong to metal additive manufacturing field;Firstly, after the dehydration treatment of metal salt powder and Variquat CC 42NS, 1,6-hexanediol diacrylate, ethoxylated trimethylolpropane triacrylate, diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide are mixed and stirred, to obtain uniform general resin;Then the general resin is printed into modeling structure using digital light processing 3D printing technology, the obtained alloy precursor sample is immersed in isopropyl alcohol solution and cleaned by ultrasonic;Finally, the cleaned alloy precursor sample is dried at room temperature, then debinding is carried out in muffle furnace, reduction is carried out in tube furnace, and finally alloy three-dimensional structure sample is obtained.The application combines simple and low-cost heat treatment process, and three-dimensional porous metal material with complex three-dimensional structure and good mechanical properties is prepared, and the preparation problem of traditional three-dimensional porous alloy material is solved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of metal additive manufacturing, and particularly relates to a digital light processing 3D printing alloy general resin and a preparation method of porous alloy. BACKGROUND

[0002] Porous metal, also commonly known as metal foam, has a wide range of applications in the field of electrochemistry due to its good electrical conductivity, light weight, and large specific surface area. In electrochemical energy storage applications, it can be used as a carrier, current collector or high specific surface area electrode. The selection of metal is usually based on surface activity, passivation, electrical conductivity and weight. Porous metal has been developed for nearly a century, and its development follows two main routes: liquid or solid processing. Both routes can form pores by controlling porosity through internal gas pressure or introducing metal around a template. Although these methods have been widely used in industry, they still have problems such as complex process flow, poor repeatability, disordered pore distribution, large final feature size of the product, and difficulty in fine control of pore size and its distribution, which are very important for electrochemical applications.

[0003] 3D printing, also known as additive manufacturing, is an intelligent and powerful manufacturing technology that has been used to manufacture precise, controllable and complex three-dimensional structures for energy devices. 3D printing is a technology that uses computer-aided design to create a three-dimensional model and then produces it layer by layer. It has shown great potential for metal manufacturing in the field of electrochemistry. For the preparation of porous metal, there are laser melting sintering, electron beam melting sintering, material extrusion and stereolithography technology. The first two can directly shape metal materials, and the last two usually prepare polymer templates combined with later metalization of the templates to shape metal materials. These methods have also been applied to other electrochemical devices such as supercapacitors and batteries. Compared with traditional preparation methods, 3D printing has the following advantages: high versatility, ability to produce any ordered high-precision porous metal, easy to achieve single-stage or hierarchical pore control, and high mechanical strength combined with topological optimization. However, the above-mentioned methods have some problems and limitations, especially powder bed fusion, which requires high-quality metal and alloy powder, and high-cost equipment. There are limitations in the preparation of refractory metals, limited printing precision, and poor surface quality of the product. Digital light processing is a new printing technology that uses light initiators and various polymer monomers to rapidly polymerize under controlled ultraviolet light to produce high-precision complex structures with high design freedom and smooth surfaces. Currently, this method has not been applied in the field of metal 3D printing. Therefore, digital light processing technology with unique structural design has great potential for the preparation of three-dimensional porous alloy materials. SUMMARY

[0004] Technical problems to be solved:

[0005] In order to avoid the shortcomings of the prior art, the present application provides a kind of digital light processing 3D printing alloy general resin and the preparation method of porous alloy, by reasonably adjusting the proportion of metal salt precursor powder and the proportion of polymer monomer, combined with simple and low-cost heat treatment process, three-dimensional porous metal material with complex three-dimensional structure, good mechanical property is prepared, the preparation problem of traditional three-dimensional porous alloy material is solved.Simultaneously, slurry printing replaces powder printing, slowly and uniformly shrinks during heat treatment process, can reduce or avoid internal residual stress of material;Inexpensive metal salt replaces high-quality metal powder as printing raw material, finally does not need high-energy light source, greatly reduces production cost;By regulating the temperature gradient of heat treatment process, the porosity of microstructure can be easily controlled, and the hierarchical porous structure is accurately controlled;The finished product will have a smaller feature size than the printing precision;It can solve the printing problem of refractory metal.

[0006] The technical scheme of the present application is: a kind of digital light processing 3D printing alloy general resin and the preparation method of porous alloy, specific steps are as follows:

[0007] Step one: the NiSO4·7H2O, CuSO4·5H2O, FeSO4·7H2O and CoSO4·7H2O metal salt hydrate particles are dehydrated, to obtain NiSO4, CuSO4, FeSO4, CoSO4 metal salt particles;Then the dehydrated metal salt particles are mixed according to a certain proportion and placed in a ball mill tank for ball milling, to obtain NiSO4, CuSO4, FeSO4, CoSO4 metal salt powder;

[0008] Step two: the mixed metal salt powder obtained in step 1 and Variquat CC 42NS, 1,6-hexanediol diacrylate, ethoxylated trimethylolpropane triacrylate, diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide are mixed and stirred to obtain a uniform general resin;The general resin is placed in a ball mill tank for ball milling until the metal salt powder in the general resin is uniformly dispersed;Then the general resin is taken out and stored in dark place;

[0009] Step three: first, use software to complete structure modeling;Then, use the general resin obtained in step two to print the structure on a digital light processing printer;Finally, immerse the alloy precursor sample obtained by printing into isopropyl alcohol solution for ultrasonic cleaning;

[0010] Step four: dry the cleaned alloy precursor sample at room temperature, then perform degreasing in a muffle furnace and reduction in a tube furnace, to finally obtain an alloy three-dimensional structure sample.

[0011] A further technical solution of the present invention is as follows: In step one, the NiSO4·7H2O, CuSO4·5H2O, FeSO4·7H2O, and CoSO4·7H2O metal hydrate particles are placed in a muffle furnace for high-temperature dehydration treatment. The dehydration temperature is 100-200℃, the heating rate is 1-10℃ / min, and the dehydration time is 3-5h.

[0012] A further technical solution of the present invention is as follows: In step one, different mixed metal salt powders are prepared according to different resin requirements, with mass ratios of: NiSO4:CoSO4 = 1:1, NiSO4:FeSO4 = 2:1, NiSO4:CoSO4:FeSO4 = 2:2:1, NiSO4:CoSO4:FeSO4:CuSO4 = 2:2:1:1; the ball milling speed is 300-500 r / min, and the ball milling time is 30-60 min.

[0013] A further technical solution of the present invention is as follows: In step two, 30-80g of metal salt powder, 3-8mL of Variquat CC 42NS, 0.5-1g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 15-30mL of 1,6-hexanediol diacrylate, and 5-10mL of ethoxylated trimethylolpropane triacrylate are mixed and ground into homogeneous material using a ball mill. The ball milling speed is 300-500r / min, and the ball milling time is 30-60min.

[0014] A further technical solution of the present invention is: in step three, the printed alloy precursor sample is ultrasonically cleaned for 5-10 minutes, and the cleaning is repeated 2-4 times.

[0015] A further technical solution of the present invention is: in step four, when degreasing is carried out in a muffle furnace, the temperature gradient is 200, 400, 600, 840 and 1000℃, the heating rate is 1-10℃ / min, and the holding time is 2-4h respectively.

[0016] A further technical solution of the present invention is as follows: In step four, when the reduction is carried out in a tube furnace, the reducing atmosphere is an Ar-H2 mixed gas, wherein H2 accounts for 10%, the gas flow rate is 200–300 mL / min, the reduction temperature is 600–1100℃, the heating rate is 1–10℃ / min, and the holding time is 4–8 h.

[0017] Beneficial effects

[0018] The beneficial effects of this invention are as follows: This invention discloses a general-purpose resin for digital light processing (DLP) 3D printing alloys and a method for preparing porous alloys. Firstly, it combines digital light processing technology (a 3D printing technology with a layer resolution of 27 μm) with a simple heat treatment technique to obtain a layered porous alloy foam with pore sizes ranging from a few nanometers to hundreds of micrometers. This preparation method also breaks through the material limitations of existing digital light processing (DLP) technology (existing technologies can only print polymer structures), achieving high-resolution metal printing directly for the first time.

[0019] High-precision printing of complex structures: Due to the technological advantages of 3D printing and the high-resolution characteristics of DLP technology, combined with computer-aided software for structural topology optimization and design, as well as raw material component ratio design, high-precision and customizable metal material preparation can be achieved based on this general-purpose alloy resin. For example... Figure 1 The images shown are SEM images of three-dimensional metal samples printed using this preparation method, representing Woodpile, Octet Truss, Gyroid, and Honeycomb structures, respectively. Figure 2 The images show a comparison of SEM images of structures printed using SLM and DLP technologies. It can be seen from the images that the structure printed using SLM technology has lower resolution and contains inclusions, while the structure printed using DLP technology has higher precision and higher sample quality.

[0020] High cost-effectiveness: Compared with laser melting printing and electron beam melting printing, it uses inexpensive metal salts instead of high-quality, high-cost metal powders as printing materials. At the same time, the equipment requirements are not high and there is no need for high-energy light sources, which greatly reduces production costs. Attached Figure Description

[0021] Figure 1 SEM images of Woodpile, Octet Truss, Gyroid, and Honeycomb structures.

[0022] Figure 2 SEM image of the structure printed by SLM (left) and SEM image of the structure printed by DLP technology (right).

[0023] Figure 3 Photographs of the alloy printing precursor and the alloy after sintering and reduction.

[0024] Figure 4 This is a scanning electron microscope image of the alloy foam.

[0025] Figure 5 This is the EDX elemental distribution map of the alloy foam.

[0026] Figure 6The images show scanning electron microscope (SEM) images of the FeCoNiCu alloy at different reduction temperatures. It can be seen that with increasing reduction temperature, the microstructure of the alloy foam gradually becomes denser, and the sintering and fusion of the metal particles becomes more pronounced.

[0027] Figure 7 The image shows the XRD pattern of the alloy.

[0028] Figure 8 This is a list of the atomic percentages of each element in the alloy foam. Detailed Implementation

[0029] The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.

[0030] This invention discloses a method for preparing a general-purpose resin and porous alloy for digital light processing 3D printing alloys. The polymer solution comprises 1,6-hexanediol diacrylate (E-HDDA), ethoxylated trimethylolpropane triacrylate (E-TMPTA), and diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), and the original powder is a mixed metal salt powder.

[0031] Example 1:

[0032] Step 1: First, NiSO4·7H2O, CoSO4·7H2O, and FeSO4·7H2O were dehydrated separately. The metal salt hydrate particles were placed in ceramic boats and dehydrated at high temperature using a muffle furnace at 150℃, a heating rate of 3℃ / min, and a dehydration time of 5 hours. Then, the dehydrated metal salt particles were mixed in a mass ratio of NiSO4:CoSO4 = 1:1 and placed in a ball mill jar for ball milling at a speed of 300 r / min for 30 minutes. Finally, they were stored in wide-mouth bottles for later use.

[0033] Step Two: Mix 50g of the mixed metal salt powder obtained in Step One, 5mL of Variquat CC 42NS (dispersant), 20mL of 1,6-hexanediol diacrylate (E-HDDA), 25mL of ethoxylated trimethylolpropane triacrylate (E-TMPTA), and 0.5g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO) to obtain a homogeneous general-purpose resin. Then, place the resin in a ball mill jar and ball mill until the powder is uniformly dispersed. The ball milling speed is 300 rpm, and the milling time is 30 minutes. Finally, remove the resin and store it in a brown wide-mouth bottle wrapped in aluminum foil to protect it from light.

[0034] Step 3: First, use computer structural design software to complete the structural modeling; then, use the general resin obtained in step 2 to print the structure on a digital light processing (DLP) printer; finally, immerse the printed alloy precursor sample in isopropanol solution for ultrasonic cleaning for 6 minutes, and clean twice.

[0035] Step 4: The printed structure is dried at room temperature, and then degreased in a muffle furnace at temperature gradients of 200, 400, 600, 840 and 1000℃, with a heating rate of 2℃ / min and a holding time of 2h. Finally, reduction is carried out in a tube furnace at an Ar-H2 mixed gas (10% H2) atmosphere of 200mL / min, a reduction temperature of 600℃, a heating rate of 5℃ / min, and a holding time of 6h, to finally obtain the alloy three-dimensional structure sample.

[0036] Scanning electron microscope image of the alloy foam prepared in Example 1, as follows: Figure 2 As shown, interconnected metal particles can be seen, indicating that the macroscopic and microscopic structures of the metal salt precursor are well preserved after sintering and chemical etching, proving the perfect replication of the double helix structure from the metal salt precursor to the 3D alloy foam.

[0037] Example 2:

[0038] Step 1: First, NiSO4·7H2O, CoSO4·7H2O, and FeSO4·7H2O were dehydrated separately. The metal salt hydrate particles were placed in ceramic boats and dehydrated at high temperature using a muffle furnace. The dehydration temperature was set at 150℃, the heating rate was 2℃ / min, and the dehydration time was 3 hours. Then, the dehydrated metal salt particles were mixed in a mass ratio of NiSO4:CoSO4 = 1:1 and placed in a ball mill jar for ball milling at a speed of 350 r / min for 30 minutes. Finally, they were stored in wide-mouth bottles for later use.

[0039] Step 2: Mix 55g of the mixed metal salt powder obtained in Step 1, 5mL of Variquat CC 42NS (dispersant), 25mL of 1,6-hexanediol diacrylate (E-HDDA), 10mL of ethoxylated trimethylolpropane triacrylate (E-TMPTA), and 0.6g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO) to obtain a homogeneous general-purpose resin. Then, place the resin in a ball mill jar and ball mill until the powder is uniformly dispersed. The ball milling speed is 350 rpm, and the milling time is 30 minutes. Finally, remove the resin and store it in a brown wide-mouth bottle wrapped in aluminum foil to protect it from light.

[0040] Step 3: First, use computer structural design software to complete the structural modeling; then, use the general resin obtained in Step 2 to print the structure on a digital light processing (DLP) printer; finally, immerse the printed alloy precursor sample in isopropanol solution for ultrasonic cleaning for 5 minutes, and clean twice.

[0041] Step 4: The printed structure is dried at room temperature, and then degreased in a muffle furnace at temperature gradients of 200, 400, 600, 840 and 1000℃, with a heating rate of 1℃ / min and a holding time of 3h. Finally, reduction is carried out in a tube furnace at an Ar-H2 mixed gas (10% H2) atmosphere of 250mL / min, a reduction temperature of 800℃, a heating rate of 5℃ / min, and a holding time of 8h, to finally obtain the alloy three-dimensional structure sample.

[0042] The EDX elemental distribution spectrum of the alloy foam prepared in Example 2 is as follows: Figure 3 As shown, the elements are uniformly distributed within the nanoscale region of the alloy foam.

[0043] Example 3:

[0044] Step 1: First, NiSO4·7H2O, CoSO4·7H2O, and FeSO4·7H2O were dehydrated separately. The metal salt hydrate particles were placed in ceramic boats and dehydrated at high temperature using a muffle furnace at 150℃, a heating rate of 3℃ / min, and a dehydration time of 5 hours. Then, the dehydrated metal salt particles were mixed in a mass ratio of NiSO4:CoSO4 = 1:1 and placed in a ball mill jar for ball milling at a speed of 350 r / min for 30 minutes. Finally, they were stored in wide-mouth bottles for later use.

[0045] Step Two: Mix 56g of the mixed metal salt powder obtained in Step One, 6mL of Variquat CC 42NS (dispersant), 22mL of 1,6-hexanediol diacrylate (E-HDDA), 23mL of ethoxylated trimethylolpropane triacrylate (E-TMPTA), and 0.7g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO) to obtain a homogeneous general-purpose resin. Then, place the resin in a ball mill jar and ball mill until the powder is uniformly dispersed. The ball milling speed is 350 rpm, and the milling time is 30 minutes. Finally, remove the resin and store it in a brown wide-mouth bottle wrapped in aluminum foil to protect it from light.

[0046] Step 3: First, use computer structural design software to complete the structural modeling; then, use the general resin obtained in step 2 to print the structure on a digital light processing (DLP) printer; finally, immerse the printed alloy precursor sample in isopropanol solution for ultrasonic cleaning for 10 minutes, and clean twice.

[0047] Step 4: The printed structure is dried at room temperature, and then degreased in a muffle furnace at temperature gradients of 200, 400, 600, 840 and 1000℃, with a heating rate of 2℃ / min and a holding time of 4h. Finally, it is reduced in a tube furnace at an Ar-H2 mixed gas (10% H2) atmosphere of 250mL / min, a reduction temperature of 1000℃, a heating rate of 5℃ / min, and a holding time of 8h, to obtain the final alloy three-dimensional structure sample.

[0048] The XRD pattern of the alloy foam prepared in Example 3 is as follows: Figure 5 As shown in the figure, the XRD patterns indicate that the reduced alloys are all solid solutions with a single FCC phase structure.

[0049] Example 4:

[0050] Step 1: First, NiSO4·7H2O, CoSO4·7H2O, and FeSO4·7H2O were dehydrated separately. The metal salt hydrate particles were placed in ceramic boats and dehydrated at high temperature using a muffle furnace at 150℃, a heating rate of 3℃ / min, and a dehydration time of 5 hours. Then, the dehydrated metal salt particles were mixed in a mass ratio of NiSO4:CoSO4 = 1:1 and placed in a ball mill jar for ball milling at a speed of 300 r / min for 30 minutes. Finally, they were stored in wide-mouth bottles for later use.

[0051] Step Two: Mix 57g of the mixed metal salt powder obtained in Step One, 5mL of Variquat CC 42NS (dispersant), 25mL of 1,6-hexanediol diacrylate (E-HDDA), 15mL of ethoxylated trimethylolpropane triacrylate (E-TMPTA), and 0.5g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO) to obtain a homogeneous general-purpose resin. Then, place the resin in a ball mill jar and ball mill until the powder is uniformly dispersed. The ball milling speed is 360 rpm, and the milling time is 30 minutes. Finally, remove the resin and store it in a brown wide-mouth bottle wrapped in aluminum foil to protect it from light.

[0052] Step 3: First, use computer structural design software to complete the structural modeling; then, use the general resin obtained in step 2 to print the structure on a digital light processing (DLP) printer; finally, immerse the printed alloy precursor sample in isopropanol solution for ultrasonic cleaning for 9 minutes, and clean it 3 times.

[0053] Step 4: The printed structure is dried at room temperature, and then degreased in a muffle furnace at temperature gradients of 200, 400, 600, 840 and 1000℃, with a heating rate of 2℃ / min and a holding time of 3h. Finally, reduction is carried out in a tube furnace at an Ar-H2 mixed gas (10% H2) atmosphere of 300mL / min, a reduction temperature of 1100℃, a heating rate of 5℃ / min, and a holding time of 6h, to finally obtain the alloy three-dimensional structure sample.

[0054] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention.

Claims

1. A method for preparing a general-purpose resin and porous alloy for digital light processing 3D printing alloys, characterized in that... The specific steps are as follows: Step 1: Dehydrate the NiSO4•7H2O, CuSO4•5H2O, FeSO4•7H2O, and CoSO4•7H2O metal salt hydrate particles to obtain NiSO4, CuSO4, FeSO4, and CoSO4 metal salt particles. Then, mix the dehydrated metal salt particles in a certain proportion and ball mill them to obtain NiSO4, CuSO4, FeSO4, and CoSO4 metal salt powders. In Step 1, the NiSO4•7H2O, CuSO4•5H2O, FeSO4•7H2O, and CoSO4•7H2O metal salt hydrate particles are placed in a muffle furnace for high-temperature dehydration treatment at a temperature of 100-200℃, a heating rate of 1-10℃ / min, and a dehydration time of 3-5 h. In Step 1, different mixed metal salt powders are prepared according to different resin requirements, with mass ratios of NiSO4:CoSO4 = 1:1, NiSO4:FeSO4 = 1:1, etc. The ratios are 2:1 for NiSO4:CoSO4:FeSO4 and 2:2:1 for CuSO4:CoSO4:FeSO4:CuSO4:2:1:1; the ball milling speed is 300-500 r / min, and the ball milling time is 30-60 min. Step 2: The mixed metal salt powder obtained in Step 1 is mixed and stirred with Variquat CC 42 NS, 1,6-hexanediol diacrylate, ethoxylated trimethylolpropane triacrylate, and diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide. The mixture consists of 30-80 g of metal salt powder, 3-8 mL of Variquat CC 42 NS, 0.5-1 g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 15-30 mL of 1,6-hexanediol diacrylate, and 5-10 mL of ethoxylated trimethylolpropane triacrylate to obtain a homogeneous general-purpose resin. The general-purpose resin is then placed in a ball mill jar and ball-milled until the metal salt powder is evenly dispersed. The general-purpose resin is then removed and stored in the dark. In Step 2, the resin is ground to homogeneity using a ball mill at a speed of 300-500 r / min for 30-60 min. Step 3: First, use software to complete the structural modeling; then, use the general resin obtained in Step 2 to print the structure on a digital light processing printer; finally, immerse the printed alloy precursor sample in isopropanol solution for ultrasonic cleaning. In step three, the printed alloy precursor sample is ultrasonically cleaned for 5-10 minutes, and the cleaning is repeated 2-4 times. Step 4: Dry the cleaned alloy precursor sample at room temperature, then degrease it in a muffle furnace and reduce it in a tube furnace to finally obtain the three-dimensional alloy structure sample. During degreasing in a muffle furnace, the temperature gradients were 200, 400, 600, 840 and 1000 °C, the heating rate was 1-10 °C / min, and the holding time was 2-4 h. When reducing in a tube furnace, the reducing atmosphere is an Ar-H2 mixture, with H2 accounting for 10%, the gas flow rate is 200-300 mL / min, the reduction temperature is 600-1100 ℃, the heating rate is 1-10 ℃ / min, and the holding time is 4-8 h.

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