Manufacturing process of high-purity and high-hardness hollow gold ornament

Abstract

The invention relates to a manufacturing process of a high-purity and high-hardness hollow gold ornament. The manufacturing process comprises the following steps that S1, a blocky gold raw material is pressed into a gold sheet with the preset thickness; s2, the gold sheet is made into a hollow gold rough blank in a preset shape; s3, the hollow gold rough blank is covered with a gold plating layer through electroplating; and S4, the gold plating layer is processed according to the preset size of the product. The hollow gold ornament has the effect that the hollow gold ornament with high purity and high hardness can be manufactured more easily.

Description

Technical Field

[0001] The present application relates to the field of jewelry processing, and in particular to a process for producing hollow gold jewelry with high purity and high hardness. Background Art

[0002] Gold, as a beautiful golden metal, is rare and precious, has high density and low hardness, good ductility and plasticity, and relatively high chemical stability. It does not oxidize with oxygen at any temperature. Pure gold is golden in color with a bright but soft luster. Therefore, it is often used to make jewelry, among which hollow jewelry is more popular because of its shape and price.

[0003] In the related art, the production process of hollow gold jewelry is made in the following way: first, a layer of gold is coated on the copper alloy by electroplating; second, holes are punched on the gold plating; third, the copper alloy inside the gold plating is removed by pickling; fourth, the holes on the gold plating are filled with gold; and fifth, the product is finished by CNC processing.

[0004] Regarding the above-mentioned related technologies, there are two defects: first, it is difficult to completely remove the copper alloy by pickling; second, it is difficult to grasp the shape accuracy of the holes in the gold plating when filling them with gold, which makes it inconvenient to control the quality of the gold jewelry, resulting in the defect that it is difficult to make hollow gold jewelry with high purity and high hardness. Summary of the invention

[0005] In order to make it easier to produce hollow gold jewelry with high purity and high hardness, the present application provides a process for producing hollow gold jewelry with high purity and high hardness.

[0006] The present application provides a high-purity and high-hardness hollow gold jewelry manufacturing process using the following technical solutions: A process for producing hollow gold jewelry with high purity and high hardness, comprising the following steps: S1. Pressing the block gold raw material into a gold sheet of a predetermined thickness; S2, forming the gold flakes into a hollow gold blank of a predetermined shape; S3, covering the hollow gold blank with a gold coating by electroplating; S4. Process the gold plating according to the predetermined size of the product.

[0007] By adopting the above technical solution, the hollow gold blank is used as a frame during electroplating, and there is no need for pickling to remove impurities after the subsequent electroplating is completed, so high purity can be easily achieved. At the same time, the gold plating can make up for the hardness of the hollow gold blank, so high hardness can also be easily achieved, thereby easily making hollow gold jewelry with high purity and high hardness.

[0008] Preferably, the S2 further comprises the following steps: S21, shaping the gold sheet into a gold splicing rough blank of a predetermined shape by a mold; S22, removing impurities from the gold splicing rough blank; S23, welding the seams of the gold spliced ​​rough blanks to form a hollow gold rough blank By adopting the above technical solution, firstly, since it is a hollow product, it can be directly made into products of different shapes with the help of a mold; secondly, the impurity removal treatment can remove the oil stains in the pressing process, thereby maintaining the purity of the product.

[0009] Preferably, before S3, the hollow gold rough blank is subjected to finishing and polishing treatments to make the hollow gold rough blank reach a predetermined shape error and surface roughness.

[0010] By adopting the above technical solution, firstly, since the change of the coating thickness cannot be completely uniform during the electroplating process, the shape error of the electroplated part can be reduced by first allowing the hollow gold rough blank to reach a predetermined shape error, and the excess gold coating removed by the subsequent finishing treatment will not be too much, so the processing cost can be reduced, and the thickness deviation of the gold coating between different positions can be smaller, thereby improving the overall hardness of the product; secondly, allowing the hollow gold rough blank to reach a predetermined surface roughness can make the gold coating and the hollow gold rough blank more closely connected, thereby helping to improve the hardness of the product.

[0011] Preferably, if the product is annular, the ratio between the cross-sectional radius of the inner cavity and the wall thickness is 1:4.

[0012] By adopting the above technical solution, products with higher hardness can be produced.

[0013] Preferably, the wall thickness of the hollow gold blank is equal to the wall thickness of the gold plating.

[0014] By adopting the above technical solution, the requirements of high purity and high hardness are taken into account and achieved with lower production costs.

[0015] Preferably, if the product is three-dimensional, the outer surface of the hollow gold rough blank is in an arcuate convex shape.

[0016] By adopting the above technical solution, the special load-bearing principle of the bow can be used to compensate for the hardness of the hollow gold rough blank, so that a hollow three-dimensional gold ornament with higher hardness can be made.

[0017] Preferably, the ratio between the wall thickness of the hollow gold blank and the wall thickness of the gold plating layer is between 1:2 and 1:3.

[0018] By adopting the above technical solution, since the product is three-dimensional, the hollow area of ​​the product will be larger. Therefore, the thickness of the gold plating is greater than the wall thickness of the hollow gold blank, which can further compensate for the weaker hardness caused by the air area, thereby making it possible to make a hollow three-dimensional gold jewelry with higher hardness.

[0019] Preferably, in S3, the gold plating is completed by multiple electroplating processes, and finishing and polishing are performed between two adjacent electroplating processes.

[0020] By adopting the above technical solution, since the thickness of the coating will not change evenly during the electroplating process, the coating surface will not be completely smooth, so electroplating is performed in multiple times, and fine processing and polishing are performed between two adjacent electroplating times, which can improve the density of the gold coating and thus improve the hardness of the product.

[0021] Preferably, in S3, the single gold plating layer close to the hollow gold rough billet is thicker than the single gold plating layer far from the hollow gold rough billet.

[0022] By adopting the above technical solution, while improving the density of the gold plating, it is also possible to speed up production efficiency, thereby achieving compatibility between production efficiency and product quality.

[0023] Preferably, if the outer surface of the product is flat but the outer surface of the hollow gold rough blank is in an arc-shaped convex shape, then in the S3, the thickness of the first gold single plating layer exceeds one-third of the arc height of the arc, and the outer surfaces of the gold single plating layers other than the last gold single plating layer are in an arc-shaped arc shape, and the convex amplitude of the outer surface of the gold single plating layer that is farther away from the hollow gold rough blank is smaller.

[0024] By adopting the above technical scheme, firstly, the thickness limit of the first gold single plating layer can avoid the hollow gold rough blank being directly worn out during polishing, thereby reducing the difficulty of production; secondly, the special shape of the outer surface of the gold single plating layer other than the last gold single plating layer can increase the contact area with the plating solution during electroplating, which can not only improve the production efficiency, but also improve the density of the gold plating layer; thirdly, the relationship between the outer surface shapes of the gold single plating layers other than the last gold single plating layer can reduce the difference in plating amount between the gold single plating layers, thereby improving the density and uniformity of the gold plating layer, and then can also improve the hardness of the product.

[0025] In summary, the present application includes at least one of the following beneficial technical effects: 1. The hollow gold rough blank is used as a frame for electroplating. After the subsequent electroplating is completed, there is no need for pickling to remove impurities. It can easily achieve high purity. At the same time, the gold plating can make up for the hardness of the hollow gold rough blank, so it can also easily achieve high hardness, so that it can easily make hollow gold jewelry with high purity and high hardness; 2. Firstly, during the electroplating process, the change in the thickness of the coating cannot be completely uniform. Therefore, firstly, the shape error of the product after electroplating can be reduced by making the hollow gold rough blank reach the predetermined shape error. The excess gold coating removed by the subsequent finishing process will not be too much, so the processing cost can be reduced. At the same time, the thickness deviation of the gold coating between different positions can be reduced, thereby improving the overall hardness of the product. Secondly, making the hollow gold rough blank reach the predetermined surface roughness can make the gold coating and the hollow gold rough blank more closely connected, thereby helping to improve the hardness of the product. 3. Because the thickness of the coating will not change evenly during the electroplating process, the surface of the coating will not be completely smooth, so it is electroplated in multiple times, and fine processing and polishing are performed between two adjacent electroplating times to improve the density of the gold coating, thereby improving the hardness of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the process of manufacturing a hollow gold ornament with high purity and high hardness disclosed in this embodiment.

[0027] Figure 2 It is a detailed flow chart of step S2 in a process for making hollow gold jewelry with high purity and high hardness disclosed in this embodiment.

[0028] Figure 3 This is a schematic diagram made in this embodiment to reflect the proportional relationship between the wall thickness of the gold plating layer and the hollow gold rough blank when the product types are different.

[0029] Figure 4 This is a schematic diagram of the specific structure of a single gold plating layer when the product is in a three-dimensional shape in this embodiment.

[0030] Explanation of the accompanying reference numerals: 1. Hollow gold blank; 2. Gold plating; 3. Single gold plating. DETAILED DESCRIPTION

[0031] The following is combined with Figure 1-4 This application is described in further detail.

[0032] The embodiment of the present application discloses a process for producing hollow gold jewelry with high purity and high hardness.

[0033] Reference Figure 1The production process of hollow gold jewelry with high purity and high hardness includes the following steps: S1. Pressing the block gold raw material into a gold sheet of a predetermined thickness; S2, forming the gold flakes into a hollow gold blank 1 of a predetermined shape; S3, covering the hollow gold blank 1 with a gold coating 2 by electroplating; S4. Process the gold plating layer 2 according to the predetermined size of the product.

[0034] From the aforementioned steps S1 to S4, the hollow gold rough blank 1 is used as a frame during electroplating. After the electroplating is completed, there is no need for pickling to remove impurities, so it is easy to achieve high purity. At the same time, the gold plating layer 2 can make up for the hardness of the hollow gold rough blank 1 with its own characteristics, so it is also easy to achieve high hardness, so that it is easier to make hollow gold jewelry with high purity and high hardness.

[0035] In this embodiment, in the steps S1-S4, in the specific implementation process, some adaptive changes need to be made in details according to the actual situation, and the specific settings are as follows: In S1, a combination of rolling and stamping can be used to achieve this. Specifically, the block gold raw material is first gradually thinned by rolling, and when it is almost pressed to a predetermined thickness, it is stamped to achieve it, so that the deviation between different thicknesses of the gold sheets can be smaller.

[0036] In S2, refer to Figure 2 , further comprising the following steps: S21, shaping the gold sheet into a gold splicing rough blank of a predetermined shape through a mold. If the product is a product such as a bracelet, the gold sheet is first wrapped on a rod as an internal support, and then the rod and the gold sheet are passed through the eyelet to shape the gold sheet into a tube. If the product is a geometric three-dimensional shape, such as a rectangular parallelepiped shape, the gold sheet is first wrapped around five faces of the rectangular parallelepiped mold core. After the gold sheet is closely attached to the five faces of the rectangular parallelepiped mold core, the rectangular parallelepiped mold core is pulled out, and then the remaining face of the gold sheet is covered; S22, removing impurities from the gold splicing rough blank, this step is mainly to remove the oil stains generated when the gold sheet contacts the equipment in S21; S23, welding the seams of the gold spliced ​​rough blanks to form a hollow gold rough blank 1.

[0037] In S3, since the thickness of the plating layer does not change uniformly during the electroplating process, the factors such as the density of the gold plating layer 2, the thickness uniformity of the gold plating layer 2 at different positions of the product and the production cost are considered. Before S3 is performed, the hollow gold rough blank 1 will be finely processed and polished so that the hollow gold rough blank 1 reaches a predetermined shape error and surface roughness.

[0038] The predetermined shape error refers to the fact that the thickness deviation of each part of the hollow gold blank 1 should not be too large. The advantage of this treatment is that it can reduce the shape error of the workpiece after electroplating, and the excess gold plating 2 removed during the subsequent finishing treatment will not be too much, so the processing cost can be reduced. At the same time, it can also make the thickness deviation of the gold plating 2 between different positions smaller, thereby improving the overall hardness of the product. In addition, it should be noted that if it is a product such as a bracelet, it is also necessary to use rolling shaping to keep the inner diameter and outer diameter errors within the predetermined range.

[0039] The predetermined surface roughness refers to making the surface of the hollow gold rough blank 1 smoother. The advantage of such treatment is that the gold plating 2 can be more closely connected to the hollow gold rough blank 1, thereby helping to improve the hardness of the product.

[0040] In S3, refer to Figure 3 The thickness of the gold plating 2 depends on the type of product. If the product is an ornament such as a bracelet, that is, the product is ring-shaped, the ratio between the cross-sectional radius of the inner cavity of the product and the wall thickness is 1:4, and the wall thickness of the hollow gold rough blank 1 is equal to the wall thickness of the gold plating 2. If the product is in the shape of a rectangular parallelepiped, that is, the product is three-dimensional, the hollow area of ​​this product is relatively large, so the outer surface of the hollow gold rough blank 1 should be arched and convex. At the same time, the ratio between the wall thickness of the hollow gold rough blank 1 and the wall thickness of the gold plating 2 is between 1:2-1:3, so as to compensate for the hardness through the arch structure and more gold plating 2.

[0041] In S3, if considering from the perspective of production efficiency, the gold plating 2 can be completed by one electroplating. If considering from the perspective of the density of the gold plating 2, the gold plating 2 can be completed by multiple electroplating. However, finishing and polishing are required between two adjacent electroplating treatments to keep the surface of the plated part smooth before the next electroplating, and to make the wall thickness difference between different areas of the plated part smaller, so that the density of the gold plating 2 can be improved, thereby improving the hardness of the product.

[0042] In S3, under the premise that the gold plating layer 2 is achieved by multiple electroplating, if production efficiency is also taken into consideration, the thickness of the single gold plating layer 3 close to the hollow gold rough blank 1 can be made thicker, and the single gold plating layer 3 away from the hollow gold rough blank 1 can be made thinner, so as to achieve compatibility between production efficiency and product quality.

[0043] In S3, refer to Figure 4 , when the product is three-dimensional, the outer surface of the product is flat, but the outer surface of the hollow gold rough blank 1 is arched and convex. In response to this situation, the following settings are made: first, the thickness of the first gold single plating layer 3 must exceed one-third of the arc height, so that the hollow gold rough blank 1 can be prevented from being worn through during polishing and leaking out of the hollow gold rough blank 1, thereby reducing the difficulty of production; second, the outer surface of the gold single plating layer 3 other than the last gold single plating layer 3 is in an arched arc shape, which can increase the contact area between the plated workpiece and the plating solution during electroplating, thereby improving the production efficiency and the density of the gold plating layer 2; third, the farther the outer surface of the gold single plating layer 3 is from the hollow gold rough blank 1, the smaller the convex amplitude, so the plating amount difference between the gold single plating layers 3 can be reduced, thereby improving the density and uniformity of the gold plating layer 2, and then the hardness of the product can also be improved.

[0044] In S4, after S3 is completed, no matter it is achieved by single electroplating or multiple electroplating, the surface of the final product must not be smooth and the thickness of the coating must not be uniform, so it is still necessary to perform fine processing by CNC to make a product of predetermined size specifications.

[0045] The implementation principle of the process for producing hollow gold jewelry with high purity and high hardness in the embodiment of the present application is as follows: the hollow gold rough blank 1 is used as a frame during electroplating, and there is no step of pickling to remove impurities after the subsequent electroplating is completed, so high purity can be easily achieved. At the same time, the gold plating layer 2 can make up for the hardness of the hollow gold rough blank 1, so high hardness can also be easily achieved, thereby making it easy to make hollow gold jewelry with high purity and high hardness.

[0046] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A process for producing hollow gold jewelry with high purity and high hardness, characterized in that: The following steps are involved: S1, pressing the block gold raw material into a gold sheet of a predetermined thickness; S2, forming the gold flakes into a hollow gold blank (1) of a predetermined shape; S3, covering the hollow gold blank (1) with a gold coating (2) by electroplating; S4. Processing the gold plating layer (2) according to the predetermined size of the product.

2. The process for making hollow gold jewelry with high purity and hardness according to claim 1 is characterized in that: The S2 further comprises the following steps: S21, shaping the gold sheet into a gold splicing rough blank of a predetermined shape by a mold; S22, removing impurities from the rough gold splicing blank; S23, welding the seams of the gold spliced ​​rough blanks to form a hollow gold rough blank (1).

3. The process for making hollow gold jewelry with high purity and high hardness according to claim 1 is characterized in that: Before S3, the hollow gold rough blank (1) is subjected to finishing and polishing treatments to make the hollow gold rough blank (1) reach a predetermined shape error and surface roughness.

4. The process for making hollow gold jewelry with high purity and high hardness according to claim 1 is characterized in that: If the product is annular, the ratio between the cross-sectional radius of the inner cavity and the wall thickness is 1:

4.

5. The process for making hollow gold jewelry with high purity and hardness according to claim 4 is characterized in that: The wall thickness of the hollow gold blank (1) is equal to the wall thickness of the gold plated layer (2).

6. The process for making hollow gold jewelry with high purity and high hardness according to claim 1 is characterized in that: If the product is three-dimensional, the outer surface of the hollow gold rough blank (1) is arched and convex.

7. The process for making hollow gold jewelry with high purity and hardness according to claim 6 is characterized in that: The ratio between the wall thickness of the hollow gold blank (1) and the wall thickness of the gold plated layer (2) is between 1:2 and 1:

3.

8. The process for making hollow gold jewelry with high purity and high hardness according to claim 1 is characterized in that: In S3, the gold plating layer (2) is completed by multiple electroplating processes, and finishing and polishing processes are performed between two adjacent electroplating processes.

9. The process for making hollow gold ornaments with high purity and hardness according to claim 8, characterized in that: In the above-mentioned S3, the single gold plating layer (3) close to the hollow gold rough billet (1) is thicker than the single gold plating layer (3) far from the hollow gold rough billet (1).

10. The process for making hollow gold ornaments with high purity and hardness according to claim 8, characterized in that: If the outer surface of the product is flat but the outer surface of the hollow gold rough blank (1) is in the shape of an arched protrusion, then in the above S3, the thickness of the first gold single plating layer (3) exceeds one third of the arc height of the arch, and the outer surfaces of the gold single plating layers (3) other than the last gold single plating layer (3) are in the shape of an arched arc surface, and the farther the outer surface of the gold single plating layer (3) is from the hollow gold rough blank (1), the smaller the protrusion amplitude of the outer surface is.

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