Preparation method of desert sand for 3D printing
By screening, pickling, washing, drying and modifying desert sand, the problem of difficult desert sand in 3D printing is solved, and desert sand that meets the 3D printing material standards is prepared, which improves its utilization rate and Productivity reduces costs and widens application areas.
Patent Information
- Application Number
- CN202310936112.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-07-28
- Publication Date
- 2025-02-14
AI Technical Summary
Desert sand is difficult to meet the material standards for 3D printing, making it difficult to print in 3D printing.
Through the processing steps of screening, pickling, water washing, drying and modification, the particle size distribution and mud content of desert sand are improved, and its fluidity and printing performance are improved.
Through the above processing steps, desert sand that meets the 3D printing material standards is prepared, which improves its utilization rate and production efficiency in 3D printing, reduces production costs, and broadens the scope of 3D printing products.
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of additive manufacturing, and in particular relates to a method for preparing desert sand for 3D printing. Background Art
[0002] Desert sand is sand formed by wind in the natural environment. This type of sand is mainly produced in large quantities by long-term physical weathering of rocks. The particle size and composition of desert sand vary depending on the desert origin, but the overall composition is not much different from conventional sand; deserts are generally more regular, with more concentrated particle sizes and higher mud content.
[0003] Binder jet 3D printing is an additive manufacturing technology that selectively sprays a liquid binder onto the surface of a powder bed and forms the powder binder into the desired shape. Binder jet printing technology can quickly produce complex part structures with high design freedom. The printed sample structure is isotropic, and the technology is compatible with almost any powder material. The printing process is carried out at room temperature and in the atmosphere. Products printed using this technology have the advantages of saving materials, short production cycle, and product diversification. It can realize the manufacture of products with complex structures and can meet the application requirements of various fields. In view of the above-mentioned shortcomings of desert sand, there is currently no related application of using desert sand as a powder raw material for 3D printing. In order to improve the utilization rate of desert sand and reduce the cost of 3D printed products, it is crucial to develop desert sand preparation technology for 3D printing. Summary of the invention
[0004] The purpose of the present invention is to propose a method for preparing desert sand for 3D printing and a method for using desert sand, so that the desert sand meets the standards of binder jet printing materials and overcomes the problem that desert sand is difficult to print.
[0005] A method for preparing desert sand for 3D printing, the preparation method comprising the following steps:
[0006] Screening of desert sand: Use 16-mesh to 375-mesh sieves to screen out desert sand that meets the range and store it.
[0007] Acid washing treatment: Place the screened desert sand in an acid solution, stir evenly to obtain desert sand mortar, and let it stand for a set time.
[0008] Water washing treatment: The desert sand mortar after pickling treatment is washed with water, and it needs to be rinsed repeatedly until the pH value of the solution after washing is 6.5 to 7.5 to obtain washed desert sand.
[0009] Drying treatment: The washed desert sand is dried and allowed to stand at room temperature to obtain dried desert sand.
[0010] Modification treatment: Mix the modified liquid with the modified powder, add dried desert sand and mix to obtain qualified mixed sand, which is then dried.
[0011] In one embodiment, the pickling step further comprises preparing an acid solution, adding water to the concentrated acid solution to dilute it, and obtaining an acid solution with a mass fraction of 5% to 50%. Preferably, the concentrated acid solution can be selected from one of sulfuric acid, p-toluenesulfonic acid, hydrochloric acid, perchloric acid, nitric acid, phosphoric acid, and hydrofluoric acid, that is, the concentrated acid solution is a highly acidic acid solution.
[0012] In one of the embodiments, in the pickling step, the screened desert sand is placed in an acid solution. Specifically, 1000 g to 5000 g of desert sand is added to 50 g to 500 g of the acid solution, and the mixture is stirred evenly for 1 min to 5 min to obtain a desert sand mortar.
[0013] In one embodiment, in the pickling step, the setting value of the standing time is 30 minutes to 60 minutes.
[0014] In one embodiment, in the drying step, the drying heating temperature is 100° C. to 200° C., the heating time is 1 h to 5 h, and the heated desert sand is allowed to stand to room temperature.
[0015] In one embodiment, in the modification step, the modified liquid accounts for 5% to 20% of the mass of the dried desert sand; the modified powder accounts for 10% to 30% of the mass of the modified liquid; this method can make the particle size of the finished sand more regular, and make the powder with small particle size aggregate into a large powder suitable for printing, so that the sand has better fluidity. Preferably, the modified liquid is an organic resin, which can be selected from unsaturated polyester resin, epoxy resin, phenolic resin, and furan resin; the modified powder is one of calcium stearate, stearic acid amide, and polyethylene wax, which is used to improve the fluidity of desert sand and enhance its strength.
[0016] In one embodiment, in the modification step, the heating temperature of the drying treatment ranges from 80°C to 180°C, and the heating time ranges from 1h to 3h.
[0017] In one embodiment, the preparation method further includes a crushing process, in which the qualified mixed sand is crushed into small sand blocks, and then a shaping process is performed to obtain printed desert sand, which is screened and stored for later use.
[0018] In one of the embodiments, in the modification step, after the drying process is completed, the qualified mixed sand is left to stand for a set time to reach room temperature, and the standing time is 1 hour to 3 hours.
[0019] Printing is performed using the printing desert sand prepared by the above preparation method, and the specific steps include:
[0020] Add curing agent to the printed desert sand, mix well and place in the powder spreading device to start printing, and set the layer thickness to 0.1mm to 1.0mm; the print head sprays the binder on the powder bed of the working box according to the layered section of the part analyzed by the software, and then the working box drops one layer, and the print head sprays the binder again, and repeats the above steps until the part is printed to obtain a desert sand green body; then place the working box in a curing furnace for curing; if the binder is an organic binder, the curing temperature is 120℃ to 240℃, and the curing time is 120min to 240min; if the binder is an inorganic binder, the curing temperature is 100℃ to 200℃, and the curing time is 100min to 240min; after curing, place the working box on a powder cleaning table to remove excess powder to obtain a printed green body.
[0021] The present invention provides a method for preparing desert sand for 3D printing. After screening, pickling, washing, drying and modification treatment in sequence, the defects of desert sand such as high mud content are improved to obtain desert sand that can be used for 3D printing, thereby improving the utilization rate of desert sand and reducing production costs. The qualified desert sand can be used to print products in the fields of sculpture, architecture, etc., thereby expanding the field of 3D printing products. DETAILED DESCRIPTION
[0022] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively below, and preferred embodiments of the present invention are provided. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly and comprehensively understood.
[0023] A method for preparing desert sand for 3D printing, the preparation method comprising the following steps:
[0024] Screening of desert sand: Use 16-mesh to 375-mesh sieves to screen out desert sand that meets the range and store it.
[0025] Pickling treatment: prepare an acid solution, add water to the concentrated acid solution to dilute it, and obtain an acid solution with a mass fraction of 5% to 50%. Place the screened desert sand in the acid solution, add 1000g to 5000g of desert sand to 50g to 500g of the acid solution, stir evenly, and the stirring time is 1min to 5min to obtain desert sand mortar. Let it stand for 30min to 60min. The concentrated acid solution is a highly acidic acid solution, which can be selected from sulfuric acid, p-toluenesulfonic acid, hydrochloric acid, perchloric acid, nitric acid, phosphoric acid, and hydrofluoric acid.
[0026] Water washing treatment: The desert sand mortar after pickling treatment is washed with water, and it needs to be rinsed repeatedly until the pH value of the solution after washing is 6.5 to 7.5 to obtain washed desert sand.
[0027] Drying treatment: The washed desert sand is dried at a drying heating temperature of 100°C to 200°C for a heating time of 1h to 5h. The heated desert sand is allowed to stand at room temperature to obtain dried desert sand.
[0028] Modification treatment: Mix the modified liquid and modified powder, and then add dried desert sand to mix, the modified liquid accounts for 5% to 20% of the mass of the dried desert sand; the modified powder accounts for 10% to 30% of the mass of the modified liquid; obtain qualified mixed sand, and perform drying treatment, the heating temperature range of the drying treatment is 80℃ to 180℃, and the heating time range is 1h to 3h. After the drying treatment is completed, the qualified mixed sand is allowed to stand for a set time to room temperature, and the standing time is 1h to 3h.
[0029] The modified liquid is an organic resin, which can be selected from unsaturated polyester resin, epoxy resin, phenolic resin, and furan resin; the modified powder is one of calcium stearate, stearic acid amide, and polyethylene wax.
[0030] Crushing process: crush the qualified mixed sand into small sand blocks, and then shape them to obtain printed desert sand, which will be screened and stored for later use.
[0031] Printing is performed using the printing desert sand prepared by the above preparation method, and the specific steps include:
[0032] Add curing agent to the printed desert sand, mix well and place in the powder spreading device to start printing, and set the layer thickness to 0.1mm to 1.0mm; the print head sprays the binder on the powder bed of the working box according to the layered section of the part analyzed by the software, and then the working box drops one layer, and the print head sprays the binder again, and repeats the above steps until the part is printed to obtain a desert sand green body; then place the working box in a curing furnace for curing; if the binder is an organic binder, the curing temperature is 120℃ to 240℃, and the curing time is 120min to 240min; if the binder is an inorganic binder, the curing temperature is 100℃ to 200℃, and the curing time is 100min to 240min; after curing, place the working box on a powder cleaning table to remove excess powder to obtain a printed green body.
[0033] Embodiment 1
[0034] A method for preparing desert sand for 3D printing, the preparation method comprising the following steps:
[0035] Screening of desert sand: Use sieves ranging from 20 mesh to 305 mesh to screen out desert sand that meets the range and store it.
[0036] Pickling treatment: prepare an acid solution, add water to the concentrated acid solution to dilute it, and obtain an acid solution with a mass fraction of 10%. Place the sieved desert sand in the acid solution, add 5000g of desert sand to 100g of the acid solution, stir evenly, stir for 5min, obtain desert sand mortar, and let stand for 60min. The concentrated acid solution can be selected from one of sulfuric acid, p-toluenesulfonic acid, hydrochloric acid, perchloric acid, nitric acid, phosphoric acid, and hydrofluoric acid.
[0037] Water washing treatment: The desert sand mortar after pickling treatment is washed with water, and it needs to be rinsed repeatedly until the pH value of the solution after washing is 6.5 to 7.5 to obtain washed desert sand.
[0038] Drying treatment: The washed desert sand is dried at a drying heating temperature of 200°C for 2 hours. The heated desert sand is allowed to stand at room temperature to obtain dried desert sand.
[0039] Modification treatment: Mix furan resin and calcium stearate powder, and then add dried desert sand to mix, with furan resin accounting for 5% of the mass of dried desert sand; calcium stearate powder accounting for 10% of the mass of modified liquid; obtain qualified mixed sand, and dry it, the heating temperature range of the drying treatment is 180℃, and the heating time is 1h. After the drying treatment is completed, let the qualified mixed sand stand for 3h to room temperature.
[0040] Crushing process: crush the qualified mixed sand into small sand blocks, and then use planetary ball mill spheroidal graphite to shape it to obtain printing desert sand. Use a 70-140 mesh sieve to screen out the printing desert sand within this range.
[0041] The specific steps of printing using the obtained printed desert sand include:
[0042] Add curing agent to the printed desert sand, mix well and place in the powder spreading device to start printing, and set the layer thickness to 0.5mm; the print head sprays the binder on the powder bed of the working box according to the layered section of the part analyzed by the software, and then the working box drops one layer, and the print head sprays the binder again, and repeats the above steps until the part is printed to obtain a desert sand green body; then the working box is placed in a curing furnace for curing; the binder uses an inorganic binder, the curing temperature is 100℃, and the curing time is 240min; after the curing is completed, the working box is placed on a powder cleaning table to remove excess powder to obtain a printed green body.
[0043] Comparison of experimental results shows that the tensile strength of the green body printed with desert sand that is not processed by the preparation method of this embodiment is 0.43 MPa, while the tensile strength of the green body printed with desert sand that is processed by the preparation method of this embodiment is 1.02 MPa, and the tensile strength is significantly improved.
[0044] Embodiment 2
[0045] A method for preparing desert sand for 3D printing, the preparation method comprising the following steps:
[0046] Screening of desert sand: Use 30-mesh to 325-mesh sieves to screen out desert sand that meets the range and store it.
[0047] Pickling treatment: prepare an acid solution, add water to the concentrated acid solution to dilute it, and obtain an acid solution with a mass fraction of 15%. Place the sieved desert sand in the acid solution, add 4000g of desert sand to 250g of the acid solution, stir evenly for 3 minutes, obtain desert sand mortar, and let it stand for 45 minutes. The concentrated acid solution can be selected from one of sulfuric acid, p-toluenesulfonic acid, hydrochloric acid, perchloric acid, nitric acid, phosphoric acid, and hydrofluoric acid.
[0048] Water washing treatment: The desert sand mortar after pickling treatment is washed with water, and it needs to be rinsed repeatedly until the pH value of the solution after washing is 6.5 to 7.5 to obtain washed desert sand.
[0049] Drying treatment: The washed desert sand is dried at a drying heating temperature of 150°C for 3 hours. The heated desert sand is allowed to stand at room temperature to obtain dried desert sand.
[0050] Modification treatment: Mix phenolic resin and polyethylene wax, and then add dried desert sand to mix, phenolic resin accounts for 8% of the mass of dried desert sand; polyethylene wax accounts for 20% of the mass of modified liquid; obtain qualified mixed sand, and dry it, the heating temperature range of the drying treatment is 150℃, and the heating time is 2h. After the drying treatment is completed, let the qualified mixed sand stand for 2h to room temperature.
[0051] Crushing treatment: crush the qualified mixed sand into small sand blocks, and then use a planetary ball mill to shape it to obtain printed desert sand. Use a 40-100 mesh sieve to screen out the printed desert sand within this range.
[0052] The specific steps of printing using the obtained printed desert sand include:
[0053] Add curing agent to the printed desert sand, mix well and place in the powder spreading device to start printing, and set the layer thickness to 0.7mm; the print head sprays the binder on the powder bed of the working box according to the layered section of the part analyzed by the software, and then the working box drops one layer, and the print head sprays the binder again, and repeats the above steps until the part is printed to obtain a desert sand green body; then the working box is placed in a curing furnace for curing; the binder uses an organic binder, the curing temperature is 180℃, and the curing time is 180min; after the curing is completed, the working box is placed on a powder cleaning table to remove excess powder to obtain a printed green body.
[0054] Comparison of experimental results shows that the tensile strength of the green body printed with desert sand that is not processed by the preparation method of this embodiment is 0.61 MPa, while the tensile strength of the green body printed with desert sand that is processed by the preparation method of this embodiment is 1.24 MPa, and the tensile strength is significantly improved.
[0055] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0056] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.
Claims
1. A method for preparing desert sand for 3D printing, characterized in that: The preparation method comprises the following steps: sieving desert sand; Pickling treatment: place the screened desert sand in an acid solution, stir evenly to obtain desert sand mortar, and let it stand for a set time; Water washing treatment: washing the desert sand mortar after the acid washing treatment with water until the pH value of the solution after washing is 6.5 to 7.5, thereby obtaining washed desert sand; Drying treatment: drying the washed desert sand and leaving it to stand at room temperature to obtain dried desert sand; Modification treatment: Mix the modified liquid with the modified powder, add dried desert sand and mix to obtain qualified mixed sand, which is then dried.
2. The method for preparing desert sand for 3D printing according to claim 1, characterized in that: The pickling treatment step also includes preparing an acid solution, adding water to dilute the concentrated acid solution to obtain an acid solution with a mass fraction of 5% to 50%.
3. The method for preparing desert sand for 3D printing according to claim 1, characterized in that: In the pickling step, the sieved desert sand is placed in an acid solution. Specifically, 1000 g to 5000 g of desert sand is added to 50 g to 500 g of the acid solution, and the mixture is stirred evenly to obtain a desert sand mortar.
4. The method for preparing desert sand for 3D printing according to claim 1, characterized in that: In the pickling step, the setting value of the standing time is 30 minutes to 60 minutes.
5. The method for preparing desert sand for 3D printing according to claim 1, characterized in that: In the drying step, the drying heating temperature is 100° C. to 200° C., and the heating time is 1 hour to 5 hours.
6. The method for preparing desert sand for 3D printing according to claim 1, characterized in that: In the modification step, the modified liquid accounts for 5% to 20% of the mass of the dried desert sand; the modified powder accounts for 10% to 30% of the mass of the modified liquid.
7. The method for preparing desert sand for 3D printing according to claim 1, characterized in that: In the modification step, the heating temperature of the drying treatment ranges from 80° C. to 180° C., and the heating time ranges from 1 h to 3 h.
8. The method for preparing desert sand for 3D printing according to claim 1, characterized in that: The preparation method also includes a crushing process, in which the qualified mixed sand is crushed, and then a shaping process is performed, and the mixed sand is screened and stored for later use.
9. The method for preparing desert sand for 3D printing according to claim 1, characterized in that: In the modification step, after the drying process is completed, the qualified mixed sand is left to stand for a set time until it reaches room temperature.