阅读说明：本技术 一种铋球的制备方法 (Preparation method of bismuth ball ) 是由 邹权林 陈应红 陈松 李帮 于 2020-11-24 设计创作，主要内容包括：本发明公开了一种铋球的制备方法,包括以下步骤：原料熔融：投入原料铋锭,控制350℃至450℃的熔融温度,待原料铋锭完全熔融后搅拌铋液5分钟至20分钟；去除氧化物：搅拌完成后控制所述铋液的温度为300℃至400℃,将浮在铋液表面的氧化物除去,然后搅拌10分钟至15分钟；重复所述去除氧化物步骤若干次；浇铸成型：将经过所述去除氧化物步骤的铋液浇铸至成型模具中,冷却后取出铋球。这种铋球的制备方法无需提供真空环境即可降低铋球成品中的氧化物含量,能以较低的成本实现高品质铋球的制造。(The invention discloses a preparation method of a bismuth ball, which comprises the following steps: melting raw materials: adding raw material bismuth ingot, controlling the melting temperature of 350-450 ℃, and stirring the bismuth liquid for 5-20 minutes after the raw material bismuth ingot is completely melted; removing the oxide: after stirring, controlling the temperature of the bismuth liquid to be 300-400 ℃, removing the oxide floating on the surface of the bismuth liquid, and then stirring for 10-15 minutes; repeating the step of removing the oxide several times; casting and molding: and casting the bismuth liquid subjected to the step of removing the oxide into a forming die, and taking out the bismuth ball after cooling. The preparation method of the bismuth ball can reduce the content of oxides in the finished bismuth ball without providing a vacuum environment, and can realize the manufacture of high-quality bismuth balls at lower cost.)

1. The preparation method of the bismuth ball is characterized by comprising the following steps of:

melting raw materials: adding raw material bismuth ingot, controlling the melting temperature of 350-450 ℃, and stirring the bismuth liquid for 5-20 minutes after the raw material bismuth ingot is completely melted;

removing the oxide: after stirring, controlling the temperature of the bismuth liquid to be 300-400 ℃, removing the oxide floating on the surface of the bismuth liquid, and then stirring for 10-15 minutes;

repeating the step of removing the oxide several times;

casting and molding: and casting the bismuth liquid subjected to the step of removing the oxide into a forming die, and taking out the bismuth ball after cooling.

2. The method for preparing bismuth balls according to claim 1, wherein the step of removing oxides comprises removing oxides by means of fishing or filtering.

3. The method for preparing bismuth balls as claimed in claim 2, wherein oxides are removed by scooping with a stainless steel spoon or by filtering with a stainless steel screen.

4. The method of manufacturing a bismuth ball as claimed in any one of claims 1 to 3, wherein after the step of removing the oxide, when the maximum length of each oxide is less than 5mm, the step of removing the oxide is stopped from being repeated.

5. The method for producing the bismuth ball according to claim 4, wherein in the step of cast molding, the bismuth ball is taken out when cooled to 80 ℃ or lower.

6. The method for preparing bismuth balls as claimed in claim 5, wherein before the step of casting, the method further comprises a step of preheating a forming mold:

the forming mold is heated to 200 to 300 ℃ over a period of 20 to 40 minutes.

7. The method for preparing the bismuth ball according to claim 5, wherein the step of casting and molding further comprises a step of grinding, and the step of grinding comprises the following steps:

firstly, a hand grinder is used for smoothly cutting off the convex part of the surface of the bismuth ball, and then a grinder is used for removing the edge angle of the surface of the bismuth ball.

8. The method for preparing a bismuth ball according to claim 6 or 7, wherein the grinding step is followed by a grinding and polishing step, and the grinding and polishing step comprises:

adding 100kg to 150kg of grinding balls into a grinding machine, adding 2kg to 5kg of brightening agent and 2kg to 5kg of pure water, keeping the vibration frequency of the grinding machine at 25Hz to 30Hz, putting the bismuth balls after continuously vibrating for 10 minutes, and finishing grinding and polishing after continuously vibrating for 30 minutes to 50 minutes.

9. The method of manufacturing a bismuth ball according to claim 8, wherein in the grinding and polishing step, after the bismuth ball is placed, the bismuth ball is ground and polished by adjusting the vibration frequency of the grinder to 35Hz to 45 Hz.

10. The method for preparing the bismuth ball according to claim 9, wherein the grinding and polishing step is followed by a cleaning and drying step, and the cleaning and drying step comprises:

and cleaning the polished bismuth ball, wiping off the moisture on the surface of the bismuth ball, and then naturally drying, drying by using a blower or removing the residual moisture on the surface of the bismuth ball by using a drying oven.

Technical Field

The invention relates to the technical field of bismuth product manufacturing, in particular to a preparation method of a bismuth ball.

Background

Bismuth is a rare metal, pure simple substance bismuth is silver white metal, the surface of bismuth is rose-red, the bismuth has strong metallic luster, and the bismuth is brittle and belongs to an orthorhombic system. Bismuth is a globally recognized, very safe and non-toxic "green" metal that will find increasingly widespread use.

Particularly, in the field of fitness equipment, lead metal is applied to a plurality of weight training equipment or sports equipment due to the reasons of excellent pressure processing performance, high density and the like, but the central nervous system of a human body is seriously injured due to the long-term close contact with the human body due to the toxicity of lead. In recent years, bismuth and lead have been found to be close in many properties and are "green metals" harmless to the human body, and thus bismuth is gradually used in fitness equipment instead of lead.

However, bismuth is oxidized in air when heated, so that most of factory manufactures choose to produce bismuth products in an air environment for cost saving, and bismuth ingots are difficult to avoid containing more oxides during storage or melting, and the oxides can influence the final performance. If the content of oxides in a finished product is reduced, the purity of the bismuth ingot serving as a raw material needs to be improved, and a vacuum or inert gas environment is provided as much as possible in the production process so as to prevent the high-temperature bismuth from reacting with oxygen, but the requirements of the production of the method on the quality and the environment of the raw material are too high, and the vacuum environment needs to be provided under the high-temperature condition, so that the production cost of bismuth products is improved, and the bismuth products with high quality and low price are difficult to provide for the public.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide a preparation method of a bismuth ball, which can reduce the content of oxides in a finished bismuth ball product without providing a vacuum environment and can realize the manufacture of a high-quality bismuth ball at lower cost.

The purpose of the invention is realized by adopting the following technical scheme:

a preparation method of a bismuth ball comprises the following steps:

melting raw materials: adding raw material bismuth ingot, controlling the melting temperature of 350-450 ℃, and stirring the bismuth liquid for 5-20 minutes after the raw material bismuth ingot is completely melted;

removing the oxide: after stirring, controlling the temperature of the bismuth liquid to be 300-400 ℃, removing the oxide floating on the surface of the bismuth liquid, and then stirring for 10-15 minutes;

repeating the step of removing the oxide several times;

casting and molding: and casting the bismuth liquid subjected to the step of removing the oxide into a forming die, and taking out the bismuth ball after cooling.

Further, the step of removing the oxides adopts a fishing or filtering mode to remove the oxides.

Further, removing oxides by using a stainless steel spoon or filtering by using a stainless steel filter screen.

Further, after the step of removing the oxide, the size of the oxide on the surface of the bismuth liquid is observed, and when the maximum length of each oxide is less than 5mm, the step of removing the oxide is stopped.

Further, in the step of casting and molding, the bismuth ball is taken out when the temperature is cooled to be below 80 ℃.

Further, before the step of casting molding, the method also comprises a step of preheating a molding die: a step of heating the molding die to 200 ℃ to 300 ℃ over a period of 20 minutes to 40 minutes.

Further, the casting step is followed by a polishing step, wherein the polishing step comprises:

firstly, a hand grinder is used for smoothly cutting off the convex part of the surface of the bismuth ball, and then a grinder is used for removing the edge angle of the surface of the bismuth ball.

Further, the grinding step is followed by a grinding and polishing step, and the grinding and polishing step comprises:

adding 100kg to 150kg of grinding balls into a grinding machine, adding 2kg to 5kg of brightening agent and 2kg to 5kg of pure water, keeping the vibration frequency of the grinding machine at 25Hz to 30Hz, putting the bismuth balls after continuously vibrating for 10 minutes, and finishing grinding and polishing after continuously vibrating for 30 minutes to 50 minutes.

Further, in the grinding and polishing step, after the bismuth ball is placed, the vibration frequency of the grinding machine is adjusted to 35Hz to 45Hz, and the bismuth ball is ground and polished.

Further, the grinding and polishing step is followed by a cleaning and drying step, and the cleaning and drying step comprises:

and cleaning the polished bismuth ball, wiping off the moisture on the surface of the bismuth ball, and then naturally drying, drying by using a blower or removing the residual moisture on the surface of the bismuth ball by using a drying oven.

The prior art methods for producing bismuth articles suffer from several drawbacks, and the present invention addresses these drawbacks. The method comprises the steps of stirring the bismuth ingot after the bismuth ingot is completely melted, so that all parts of the bismuth ingot can be heated more uniformly, and oxide impurities contained in the bismuth ingot can float upwards to be removed conveniently. In the step of removing the oxide, the temperature of the bismuth liquid is kept between 300 ℃ and 400 ℃, so that the melting point of the bismuth liquid is kept to be higher than 271.3 ℃ so that the bismuth liquid can not be solidified, and impurities such as the oxide can float upwards. And then, the step of removing the oxide is carried out, so that even if the bismuth ingot raw material is oxidized due to reasons such as improper storage, the oxide in the bismuth ingot raw material can be removed in the subsequent process, the finally formed bismuth ball is not greatly influenced, the quality and the yield of the finished bismuth ball are ensured, and the requirements on the quality of the bismuth ingot raw material and the storage condition of the bismuth ingot raw material are reduced. And the whole process of manufacturing the bismuth ball can be operated in the air, so that the requirement on the manufacturing environment is reduced. Therefore, the bismuth ball is elongated by adopting the preparation method of the bismuth ball, so that the manufacturing cost can be reduced from all aspects, and the bismuth ball can be conveniently manufactured in a factory in large batch to meet the market demand.

Drawings

Fig. 1 is a flow chart of a preparation method of a bismuth ball of the present invention.

Detailed Description

The present invention will be further described with reference to the accompanying drawings and the detailed description, and it should be noted that any combination of the embodiments or technical features described below can be used to form a new embodiment without conflict.

In the description of the present application, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a particular orientation, be constructed in a particular orientation, and be operated, and thus should not be construed as limiting the present application.

The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless otherwise specified.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may be present.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

FIG. 1 shows a preparation method of a bismuth ball of the invention, which comprises a raw material melting step, an oxide removing step and a casting forming step,

the raw material melting step comprises the steps of feeding a raw material bismuth ingot, controlling the melting temperature of 350-450 ℃, and stirring the bismuth liquid for 5-20 minutes after the raw material bismuth ingot is completely melted;

the step of removing the oxide comprises the steps of controlling the temperature of the bismuth liquid to be 300-400 ℃ after stirring is finished, removing the oxide floating on the surface of the bismuth liquid, and then stirring for 10-15 minutes; repeating the step of removing the oxide several times;

and the step of casting and molding comprises the steps of casting the bismuth liquid subjected to the step of removing the oxide into a molding die, and taking out the bismuth ball after cooling.

The method carries out the stirring step after the bismuth ingot as the raw material is completely melted, so that each part of the bismuth ingot can be heated more uniformly, and oxide impurities contained in the bismuth ingot can float upwards and are convenient to remove. In the step of removing the oxide, the temperature of the bismuth liquid is kept between 300 ℃ and 400 ℃, so that the melting point of the bismuth liquid is kept to be higher than 271.3 ℃ so that the bismuth liquid can not be solidified, and impurities such as the oxide can float upwards. And then, the step of removing the oxide is carried out, so that even if the bismuth ingot raw material is oxidized due to reasons such as improper storage, the oxide in the bismuth ingot raw material can be removed in the subsequent process, the finally formed bismuth ball is not greatly influenced, the quality and the yield of the finished bismuth ball are ensured, and the requirements on the quality of the bismuth ingot raw material and the storage condition of the bismuth ingot raw material are reduced. And the whole process of manufacturing the bismuth ball can be operated in the air, so that the requirement on the manufacturing environment is reduced.

As a preferred embodiment of the step of removing the oxide, the oxide is removed by adopting a fishing or filtering mode in the step of removing the oxide, and the oxide floats on the surface of the bismuth liquid after being stirred and heated, so that the oxide floating on the surface can be directly removed by adopting the fishing mode, and the method is intuitive and simple; in addition, because the pure bismuth liquid is in a molten state, and the bismuth oxide is in a stable solid state, the oxide can be removed in a filtering mode, the oxide which does not float in the bismuth liquid can be taken out in the filtering mode, and the aperture of the filter screen is reasonably set. In terms of selection of the removal tool, the stainless steel spoon or the stainless steel filter screen is preferred in the embodiment to remove or filter the oxides, and the stainless steel has the advantages of stable property, high melting point, low price, easiness in processing and the like, so that the stainless steel spoon and the stainless steel filter screen are suitable for being used as a tool for taking out the oxides. However, it should be noted that, besides stainless steel, any other stable metal (such as titanium) or non-metal material (such as quartz) with a melting point higher than 300 ℃ to 400 ℃ can be used for manufacturing the removal tool, and the invention is within the scope of protection.

And (3) as a standard for judging when the removal of the oxide is stopped, observing the size of the oxide on the surface of the bismuth liquid, and stopping repeating the step of removing the oxide when the maximum length of each oxide is less than 5mm, wherein the content of the oxide in the bismuth liquid is extremely low, and the purity of the finally formed bismuth ball can reach more than 99.99%.

As a preferable scheme of the casting step in this embodiment, the bismuth ball is taken out after being cooled to below 80 ℃, and the bismuth ball is shaped at this temperature without too high temperature, so that the next process is suitable for being performed.

In order to make the flatness of the surface of the bismuth sphere after casting and forming higher, the present embodiment preferably further includes a step of heating the forming mold to 200 to 300 ℃ within a time period of 20 to 40 minutes before the casting and forming step. The bismuth liquid entering the forming die is not solidified immediately by the mode, but is uniformly distributed on each part of the die and then solidified along with the gradual reduction of the temperature, and the surface of the finally formed bismuth ball is very flat and can be directly ground and polished.

In addition, if the surface of the bismuth ball after casting molding has more edge protrusions and the like, the casting molding step further comprises a polishing step, and the polishing step comprises: firstly, a hand grinder is used for smoothly cutting off the convex part of the surface of the bismuth ball, and then a grinder is used for removing the edge angle of the surface of the bismuth ball. This step is used to remove the bulky and obvious bumps and corners, etc., and the shape of the bismuth ball is close to that of the finished product, so as to enter the next grinding and polishing step.

In order to ensure the flatness of the surface of the finished bismuth ball, the grinding step is followed by a grinding and polishing step, and the grinding and polishing step comprises the following steps: adding 100kg to 150kg of grinding balls into a grinding machine, adding 2kg to 5kg of brightening agent and 2kg to 5kg of pure water, keeping the vibration frequency of the grinding machine at 25Hz to 30Hz, putting the bismuth balls after continuously vibrating for 10 minutes, and finishing grinding and polishing after continuously vibrating for 30 minutes to 50 minutes. The surface of the bismuth ball after grinding and polishing is smooth and flat, and no depression or protrusion can be seen by naked eyes.

In order to further improve the grinding and polishing effect, in the grinding and polishing step, after the bismuth ball is placed, the vibration frequency of the grinding machine is adjusted to 35Hz to 45Hz, and the bismuth ball is ground and polished. The vibration frequency is increased, and the smoothness of the finished product obtained by grinding is higher.

After grinding, bismuth ball chips and the like can be adhered on the grinding and polishing device, and in order to ensure the cleanness of the product, the grinding and polishing device further comprises a cleaning and drying step, wherein the cleaning and drying step comprises the following steps: and cleaning the ground and polished bismuth balls, wiping off water on the surfaces of the bismuth balls, then air-drying residual water on the surfaces, blowing each bismuth ball for 1-3 minutes, and drying to obtain finished bismuth balls. The water for cleaning can be common tap water, and preferably pure water is used to prevent impurities in the water from damaging the quality of the surface of the bismuth ball.

Two more specific examples are provided below to illustrate the scheme of the present invention:

the first embodiment is as follows:

putting 900kg of raw material bismuth ingot into a smelting furnace with the volume of 100L continuously, controlling the temperature of the smelting furnace to be raised to 380-400 ℃, stirring the raw material bismuth ingot by using a stainless steel spoon after the bismuth ingot is completely melted, keeping the stirring time for 10 minutes, then controlling the temperature of the smelting furnace to be 350 ℃, fishing out the oxide on the surface of the bismuth liquid by using the stainless steel spoon, standing for 15-20 minutes after each time of slag fishing, stirring for 10-15 minutes, carrying out slag fishing operation for a plurality of times, and when fishing out for the 12 th time, enabling the size of each oxide on the surface of the bismuth liquid to be smaller than 5 mm.

And (3) installing a forming die, pouring the bismuth liquid obtained in the previous step into the forming die, cooling the die to below 80 ℃, and demoulding to take out the bismuth ball. If the surface of the bismuth ball has obvious bulges or edges and corners, and the like, the bismuth ball is removed by a hand mill. And (3) placing the bismuth ball into a grinding machine with the frequency of 40Hz, vibrating for 40 minutes, washing with pure water after the vibration is finished, wiping and drying, and thus obtaining the bismuth ball product with the corresponding weight specification. The test data are shown in the following table at different slag dragging times. It can be seen that when the slag is fished for 12 times, the qualified rate can reach more than 95% when the size of each oxide on the surface of the bismuth liquid is less than 5mm, and the yield is high.

Example two:

putting 900kg of raw material bismuth ingot into a smelting furnace with the volume of 100L continuously, controlling the temperature of the smelting furnace to be raised to 380-400 ℃, stirring the raw material bismuth ingot by using a stainless steel spoon after the bismuth ingot is completely melted, keeping the stirring time for 10 minutes, then controlling the temperature of the smelting furnace to be 350 ℃, fishing out the oxide on the surface of the bismuth liquid by using the stainless steel spoon, standing for 15-20 minutes after each time of slag fishing, stirring for 10-15 minutes, and carrying out 12 times of slag fishing operation, wherein the size of each oxide on the surface of the bismuth liquid is smaller than 5 mm.

And (3) installing a forming die, pouring the bismuth liquid obtained in the previous step into the forming die, cooling the die to different temperatures, and demoulding to take out the bismuth ball. If the surface of the bismuth ball has obvious bulges or edges and corners, and the like, the bismuth ball is removed by a hand mill. And (3) placing the bismuth ball into a grinding machine with the frequency of 40Hz, vibrating for 40 minutes, washing with pure water after the vibration is finished, wiping and drying, and thus obtaining the bismuth ball product with the corresponding weight specification. The test data at different demolding temperatures are shown in the table below. It can be seen that when the demolding temperature is less than 80 ℃, the qualification rate can reach more than 95 percent, and the yield is higher.

The above embodiments are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereby, and any insubstantial changes and substitutions made by those skilled in the art based on the present invention are within the protection scope of the present invention.