Method for manufacturing ceramic clay blank by using wire drawing internal mold method

Abstract

The invention provides a method for manufacturing a ceramic clay blank by using a wire drawing internal mold method. Comprising the following steps: S1, forming an inner wire mold: winding a flexible wire on a supporting rod according to a preset path to form the inner wire mold with a target special-shaped contour, and reserving at least one free wire end at the winding starting end; drawing out the supporting rod after the inner wire mold is formed; s2, clay shaping: uniformly covering the outer surface of the inner line mold with a clay layer, and enabling the thickness of the clay layer to be matched with the special-shaped outline of the inner line mold; s3, drying and shaping in the shade: placing the inner wire mold covered with the clay layer in an environment with the humidity of less than or equal to 40% for drying in the shade until the water content of the clay layer is reduced to 8-12%; s4, pulling away the inner wire mold: pulling away the flexible wire rod through the free wire end along the reverse direction of the winding path, so that the inner wire mold is completely separated from the inner cavity of the clay layer; and S5, firing and forming: putting the ceramic clay layer after the inner line mold is pulled out into a kiln, and firing to obtain the special-shaped ceramic product with the hollow structure.

Description

Technical Field

[0001] The present invention relates to the field of pottery making techniques, and particularly to a method for making ceramic green bodies using a wire-drawing internal mold method. Background Art

[0002] Pottery is a practical or ornamental object made from clay, pottery clay, or porcelain clay through processes such as shaping, decoration, and firing. Its history can be traced back to the impressed pottery and painted pottery of the Neolithic Age. The emergence of primitive porcelain during the Shang and Zhou dynasties marked the transition from pottery to porcelain. During the Tang and Song dynasties, Jingdezhen became the national porcelain-making center, and varieties such as blue and white porcelain and blue and white porcelain emerged one after another. During the Ming and Qing dynasties, the craftsmanship reached maturity, and techniques such as enamel color and famille rose enriched ceramic decoration.

[0003] The wheel-throwing method is the main method for manually preparing pottery at present. The wheel-throwing method relies on a rotating potter's wheel and manual shaping. Although it can efficiently produce round or symmetrical shapes, there are many problems. The pottery made by the wheel-throwing method has a single shape, is only suitable for regular geometric bodies such as cylinders and bowls, and it is very difficult to achieve the production of special-shaped structures. Moreover, it requires long-term practice to master the skill of applying force evenly, and the yield rate is low. Large or ultra-thin shapes are prone to deformation or cracking due to centrifugal force.

[0004] Some complex pottery also uses the segmented splicing method. Complex pottery needs to be made in parts and then glued together. Cracks are likely to occur at the glued joints due to differences in the shrinkage rate of the clay, and secondary repair is required. The production cycle is extended by 2-3 times, and the surface of the joint is rough. Moreover, it is difficult to ensure the geometric matching degree between parts by manual splicing, and the error is often very large. Summary of the Invention

[0005] In order to solve the problems in the prior art that it is difficult to balance the forming accuracy, production efficiency, and product reliability of complex special-shaped pottery, the present invention provides a method for making ceramic green bodies using a wire-drawing internal mold method.

[0006] A method for making ceramic green bodies using a wire-drawing internal mold method provided by the present invention adopts the following technical solutions:

[0007] A method for making ceramic green bodies using a wire-drawing internal mold method; includes the following steps:

[0008] S1. Inner mold forming: winding a flexible wire around a support rod along a preset path to form an inner mold with a target special-shaped contour, and leaving at least one free wire end at the starting end of the winding; after the inner mold is formed, the support rod is withdrawn.

[0009] S2. Clay shaping: evenly covering a layer of clay on the outer surface of the inner mold so that the thickness of the clay layer matches the special-shaped contour of the inner mold.

[0010] S3. Air-drying and shaping: Place the inner wire mold covered with the clay layer in an environment with a humidity ≤ 40% for air-drying treatment until the moisture content of the clay layer drops to 8% - 12%;

[0011] S4. Removing the inner wire mold: Pull out the flexible wire along the reverse direction of the winding path through the free wire end, so that the inner wire mold is completely separated from the inner cavity of the clay layer;

[0012] S5. Firing and shaping: Place the clay layer after removing the inner wire mold in a kiln for firing to obtain a special-shaped ceramic artware with a hollow structure.

[0013] As a further preference of the above manufacturing method, the flexible wire is a tensile-resistant material, and the diameter of the flexible wire is 0.5 mm - 5 mm; its tensile strength ≥ 50 MPa, and the surface roughness Ra ≤ 0.5 μm;

[0014] As a further preference of the above manufacturing method, the flexible wire can be selected from one of nylon thread, impregnated cotton rope or hemp rope;

[0015] As a further preference of the above manufacturing method, the winding path in step S1 is one of spiral winding, cross winding or segmented winding, and the distance between adjacent flexible wires is 0.5 mm - 3 mm;

[0016] As a further preference of the above manufacturing method, the environmental temperature for air-drying treatment in step S3 is 20°C - 30°C, and the air-drying process is accelerated by intermittent air flow disturbance;

[0017] As a further preference of the above manufacturing method, the raw materials of the clay layer include, by weight: 40 - 60 parts of kaolin, 10 - 20 parts of quartz sand, 5 - 10 parts of bentonite, and 25 - 35 parts of water;

[0018] As a further preference of the above manufacturing method, the special-shaped contour of the inner wire mold can be one of a gourd shape, a multi-curved geometric body or a bionic shape, and its maximum inner diameter is 5 mm - 500 mm;

[0019] As a further preference of the above manufacturing method, the support rod is a rotatable return shaft, and an elastic reset mechanism is arranged inside it, which can automatically retract the wound wire when the flexible wire is pulled out;

[0020] As a further preference of the above manufacturing method, a fixed support can be sleeved on the outside of the support rod to prevent the bottom of the inner wire mold from collapsing during winding. The fixed support can be made by 3D printing, and through holes are provided inside and it has an interference fit with the support rod.

[0021] In summary, the beneficial effects of the present invention are:

[0022] Through the flexible wire winding and the lossless extraction of the inner wire mold, the present invention can replace the traditional process and realize the production of ceramic artworks with complex special-shaped structures. The flexible wire can be freely wound into any geometric inner wire mold, and supports the special-shaped design of asymmetry and multi-curved surfaces. Compared with the throwing method, it can produce various types of vessels with an inner diameter ranging from 5 mm to 500 mm, effectively improving the applicability. Moreover, this production method is simple and easy to operate, suitable for beginners to quickly understand and produce ceramic artworks. At the same time, for the splicing forming method, it can eliminate the seam defects and improve the strength of the finished product. The integrated forming avoids segmented bonding, and the compressive strength of the finished product is effectively improved.

[0023] Through the production method provided by the present invention, there is no need to customize the mold, the single-piece material cost is only the loss of the wire, and the wire can be recycled, and can be reused more than 100 times including the support rod. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the winding and forming of the inner wire mold of the present invention;

[0025] Figure 2 It is a schematic diagram of processing the clay layer after the inner wire mold of the present invention is formed;

[0026] Figure 3 It is a schematic diagram of the installation relationship between the fixed support and the support rod of the present invention.

[0027] As shown in the figure: 1 - flexible wire, 2 - support rod, 3 - inner wire mold, 4 - free wire end, 5 - clay layer, 6 - fixed support. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] The following further elaborates on the present invention in conjunction with the attached Figures 1-3 For a more detailed description of the present invention:

[0029] The embodiment of the present invention discloses a method for manufacturing a ceramic blank using the wire-drawing inner mold method, including the following steps:

[0030] S1. Forming the inner wire mold 3: Wind the flexible wire 1 around the support rod 2 along a preset path to form an inner wire mold 3 with a target special-shaped contour, and reserve at least one free wire end 4 at the starting end of the winding; after the inner wire mold 3 is formed, extract the support rod 2;

[0031] S2. Shaping the clay: Uniformly cover the outer surface of the inner wire mold 3 with the clay layer 5 so that the thickness of the clay layer 5 matches the special-shaped contour of the inner wire mold 3;

[0032] S3. Air-drying and shaping: Place the inner wire mold 3 covered with the clay layer 5 in an environment with a humidity ≤ 40% for air-drying treatment until the moisture content of the clay layer 5 drops to 8% - 12%;

[0033] S4. Inner mold 3 extraction: Pull the flexible wire 1 in the opposite direction of the winding path through the free end 4, so that the inner mold 3 is completely separated from the inner cavity of the clay layer 5;

[0034] S5. Firing and shaping: Place the clay layer 5 after extracting the inner mold 3 in a kiln for firing to obtain a special-shaped ceramic artware with a hollow structure.

[0035] The flexible wire 1 is made of anti-tensile material, and the diameter of the flexible wire 1 is 0.5 mm - 5 mm; its tensile strength ≥ 50 MPa, and the surface roughness Ra ≤ 0.5 μm; the flexible wire 1 can be selected from one of nylon wire, impregnated cotton rope or hemp rope; the wire diameter range is limited to 0.5 - 5 mm; ensuring that it can support the weight of the clay and is easy to extract, and the anti-tensile strength ≥ 50 MPa ensures that it does not break during the winding process, and the mirror treatment with a surface roughness Ra ≤ 0.5 μm can reduce the adhesion of the clay; otherwise, when the wire diameter is too small, it is easy to cause insufficient structural strength of the ceramic body, and when it is too large, it will affect the precision of the special-shaped contour;

[0036] In step S1, the winding path is one of spiral winding, cross winding or segmented winding, and the distance between adjacent flexible wires 1 is 0.5 mm - 3 mm; spiral winding can make the axial strength high; cross winding can enhance the anti-side pressure ability; segmented winding is suitable for complex shapes, and the three modes correspond to different structural requirements; the distance is limited to 0.5 - 3 mm, too small is easy to cause difficult penetration of the clay, and too large is insufficient support;

[0037] In step S3, the ambient temperature for air drying treatment is 20°C - 30°C, and the air drying process is accelerated by intermittent air flow disturbance; the temperature range of 20 - 30°C can avoid stress cracking caused by rapid dehydration, and the environment with humidity ≤ 40% combined with intermittent air flow disturbance can increase the drying efficiency by 30% and make the moisture content gradient balanced;

[0038] It is also obtained through actual operation that when the temperature exceeds 35°C, it will cause surface hardening and hinder the diffusion of internal moisture;

[0039] The raw materials of the clay layer 5 include, by weight: 40 - 60 parts of kaolin, 10 - 20 parts of quartz sand, 5 - 10 parts of bentonite, and 25 - 35 parts of water;

[0040] The special-shaped contour of the inner mold 3 can be one of a gourd shape, a multi-curved geometric body or a bionic shape, and its maximum inner diameter is 5 mm - 500 mm;

[0041] The support rod 2 is a rotatable return shaft, and an elastic reset mechanism is arranged inside it, which can automatically retract the wound wire when the flexible wire 1 is extracted;

[0042] A fixing bracket 6 can be sleeved on the outer side of the support rod 2 to prevent the bottom of the inner wire mold 3 from collapsing during winding. The fixing bracket 6 can be made by 3D printing, with through holes opened inside and an interference fit with the support rod 2;

[0043] Example 1: Making a small gourd-shaped pottery with an inner diameter of 50 mm

[0044] 1) Material selection:

[0045] Flexible wire 1: Nylon wire with a diameter of 1 mm, tensile strength of 60 MPa, and surface roughness Ra = 0.2 μm;

[0046] Support rod 2: Stainless steel return shaft with a built-in spiral spring, diameter of 8 mm, and length of 300 mm;

[0047] Pottery clay formula: 50 parts of kaolin, 15 parts of quartz sand, 8 parts of bentonite, and 30 parts of water

[0048] 2) Implementation steps:

[0049] S1. Forming the inner wire mold 3: Fix the starting end of the nylon wire at the top of the support rod 2 and wind it in a spiral path to form a gourd-shaped inner wire mold 3: the upper sphere has a diameter of 40 mm, the lower sphere has a diameter of 60 mm, the waist has a diameter of 20 mm, and a free wire head 4 with a length of 10 cm is reserved.

[0050] S2. Shaping the pottery clay: Use a spatula to evenly cover the surface of the inner wire mold 3 with the pottery clay, with a thickness of 3 mm; the error is ±0.5 mm.

[0051] S3. Air-drying and shaping: At a temperature of 25 °C and a humidity of 35%, air-dry for 48 hours until the moisture content reaches 10%.

[0052] S4. Removing the inner wire mold 3: Slowly pull out the wire head from top to bottom at a constant speed.

[0053] S5. Firing and shaping.

[0054] 3) Results of making the inner wire mold 3: In 10 experiments, it was successfully removed 9 times, with a success rate of 90%.

[0055] Example 2: Making a large-scale sculpture pottery with an inner diameter of 500 mm

[0056] 1) Material selection:

[0057] Flexible wire 1: Hemp rope with a diameter of 3 mm, tensile strength of 55 MPa, and Ra = 0.4 μm;

[0058] Support rod 2: Stainless steel return shaft with a built-in spiral spring, diameter of 15 mm, and length of 1500 mm;

[0059] Clay formula: 60 parts of kaolin, 20 parts of quartz sand, 10 parts of bentonite, 35 parts of water;

[0060] 2) Implementation steps:

[0061] S1. Inner mold 3 forming: Winding in sections, decomposing the sculpture into three parts with a head diameter of 200 mm, a middle diameter of 500 mm, and a base diameter of 300 mm; using cross winding and spiral winding respectively.

[0062] S2. Clay shaping: The thickness of the bottom layer of clay is 5 mm, the thickness of the surface layer after fine trimming is 2 mm, and the total thickness is 7 mm.

[0063] S3. Air drying and shaping: At a temperature of 28 °C and a humidity of 30%, air drying for 120 hours until the moisture content reaches 10%.

[0064] S4. Withdrawal of the inner mold 3: First withdraw the wire of the head, and then synchronously withdraw the middle part and the base.

[0065] S5. Firing and forming.

[0066] 4) Results of the production of the inner mold 3: After withdrawal, the maximum deformation of the clay blank is <0.3 mm, meeting the accuracy requirements of large-scale artworks; the total time consumption is reduced by 30% compared with the traditional segmented splicing method, and no mold production is required.

[0067] The above shows and describes the basic principles, main features and advantages of the present invention. Each component mentioned in the present invention is a common technology in the existing field. Those skilled in the art of this industry should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for making ceramic blank by using the internal die method of drawing wire; characterized in that: Including the following steps: S1. Inner mold forming: winding the flexible wire (1) around the support rod (2) along a preset path to form an inner mold (3) with a target special-shaped contour, and leaving at least one free wire end (4) at the starting end of winding; after the inner mold (3) is formed, the support rod (2) is drawn out; S2. Clay shaping: uniformly covering a clay layer (5) on the outer surface of the inner mold (3) so that the thickness of the clay layer (5) matches the special-shaped contour of the inner mold (3); S3. Air drying and shaping: placing the inner mold (3) covered with the clay layer (5) in an environment with a humidity ≤ 40% for air drying treatment until the moisture content of the clay layer (5) drops to 8% - 12%; S4. Inner mold extraction: pulling out the flexible wire (1) along the opposite direction of the winding path through the free wire end (4) so that the inner mold (3) completely detaches from the inner cavity of the clay layer (5); S5. Firing and forming: placing the clay layer (5) after the inner mold is extracted in a kiln for firing to obtain a special-shaped pottery with a hollow structure.

2. A method for making a ceramic blank by using the internal die method of drawing wire according to claim 1, characterized in that, The flexible wire (1) is a tensile-resistant material, and the diameter of the flexible wire (1) is 0.5 mm - 5 mm; its tensile strength ≥ 50 MPa, and the surface roughness Ra ≤ 0.5 μm.

3. A method for making a ceramic blank by using the wire-drawing internal mold method according to claim 2, characterized in that, The flexible wire (1) can be selected from one of nylon wire, rubber-impregnated cotton rope or hemp rope.

4. A method for manufacturing a ceramic blank using the wire-drawing internal mold method according to claim 1, characterized in that, The winding path in step S1 is one of spiral winding, cross winding or segmented winding, and the distance between adjacent flexible wires (1) is 0.5 mm - 3 mm.

5. A method for manufacturing a ceramic blank using the wire-drawing internal mold method according to claim 1, characterized in that, In step S3, the ambient temperature for air drying treatment is 20°C - 30°C, and the air drying process is accelerated by intermittent air flow disturbance.

6. A method for manufacturing a ceramic blank using the internal die method of drawing wire, according to claim 1, characterized in that, The raw materials of the clay layer (5) include, by weight: 40 - 60 parts of kaolin, 10 - 20 parts of quartz sand, 5 - 10 parts of bentonite, and 25 - 35 parts of water.

7. A method for manufacturing a ceramic blank using the wire-drawing internal mold method according to claim 1, characterized in that, The special-shaped contour of the inner mold (3) can be one of a gourd shape, a multi-curved geometric body or a bionic shape, and its maximum inner diameter is 5 mm - 500 mm.

8. A method for manufacturing a ceramic green body using the draw wire internal mold method according to claim 1, characterized in that, The support rod (2) is a rotatable return shaft, and an elastic reset mechanism is arranged inside it, which can automatically retract the wound wire when the flexible wire (1) is drawn out.

9. A method for manufacturing a ceramic green body by using the internal die method of drawing wire, as claimed in claim 1, wherein A fixed support (6) can be sleeved on the outer side of the support rod (2) to hold the bottom of the inner mold (3) to prevent collapse during winding. The fixed support (6) can be made by 3D printing, and a through hole is opened inside it, and there is an interference fit with the support rod (2).

Images