Method for preparing a low-boron spheroidizing agent

Abstract

To provide a method for preparing a low-boron spheroidizing agent.SOLUTION: Disclosed is a method for preparing a low-boron spheroidizing agent, which comprises: a step 1 of mixing various raw materials at a fixed ratio, where the raw materials required include magnesium ingots, metallic calcium, ferrosilicon, iron scrap, rare earth, aluminum, and the like, and mixing the mixed materials by an automatic batching system; a step 2 of transporting the prepared raw materials into a smelting furnace by a conveyance system for smelting; and a step 3 of continuously measuring and monitoring a temperature in the furnace in the process of smelting the raw materials in the smelting furnace. By adopting the method for preparing the spheroidizing agent of the present application, a low-boron spheroidizing agent having a boron content of 40 ppm or less can be produced.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to the technical field of spheroidizing agents, and particularly to a method for preparing a low-boron spheroidizing agent.

Background Art

[0002] A spheroidizing agent is a specific metal or alloy added to molten iron to obtain spheroidal graphite cast iron. The commonly used one in China is ferrosilicon rare earth magnesium spheroidizing agent. The preparation process of the spheroidizing agent includes thermal remelting, low silicon granulation, etc. Depending on the influence of various elements in the spheroidizing agent on spheroidization, reasonable distribution, optimization of the production process, and improvement of the quality of ductile cast iron are always issues that casting engineers are researching. With the increasing requirements of customers for product quality, the currently commercially available spheroidizing agents have a high boron content and cannot meet the preparation of special ductile cast iron. The boron content of currently commercially available spheroidizing agents is generally 60 ppm or more and cannot meet the preparation requirements of special ductile cast iron. Trace elements in the spheroidizing agent, for example, the boron element in the spheroidizing agent, have a great influence on the quality of spheroidization, such as the influence on graphite and the matrix structure. Therefore, it is necessary to control the boron content in the spheroidizing agent, and preparing a spheroidizing agent with a boron content of 50 ppm or less has become a technical issue.

Summary of the Invention

Problems to be Solved by the Invention

[0003] In view of this point, the present invention provides a method for preparing a low-boron spheroidizing agent to solve the problem that the existing technology cannot prepare a spheroidizing agent with a boron content of 50 ppm or less.

Means for Solving the Problems

[0004] To solve the above technical problems, the method for preparing a low-boron spheroidizing agent provided by the present invention includes the following components. A method for preparing a low-boron spheroidizing agent, Step 1 involves mixing various raw materials in a fixed proportion, where the required raw materials include magnesium ingots, metallic calcium, ferrosilicon, iron scrap, rare earth elements, and aluminum, and blending them using an automated batching system. Step 2 involves transporting the blended raw materials into the smelting furnace via a transport system for smelting, Step 3 involves continuously measuring and monitoring the temperature inside the furnace during the process of smelting raw materials in the smelting furnace. Step 4 involves casting and ingot formation after the smelting process is complete. Step 5 involves using a sealed, oxygen-free rapid condenser to cool the metal ingot in a timely manner after the ingot formation is complete, thereby reducing the amount of unusable magnesium in the metal ingot and making the product quality more stable and controllable. Step 6 involves crushing the metal ingot to a specific particle size using a crushing device after cooling, specifically, the particle size can be crushed according to customer needs. Step 7 involves inspecting the product after grinding is complete to ensure its quality, Step 8 includes storing the products in batches after inspection is complete until use.

[0005] Furthermore, in order to prevent a large amount of boron from being contained in the smelting furnace, the preparation method for the smelting furnace is as follows. (1) First, mix the smelting furnace material and the adhesive, (2) Construct the furnace lining, (3) Accelerate hardening with carbon dioxide for 15 minutes, (4) Allow the furnace body to dry for 6 to 8 hours.

[0006] Furthermore, the material of the smelting furnace is a neutral material, and the pH value of the neutral material is 7.

[0007] Furthermore, the elements contained in the spheroidizing agent prepared using the above-mentioned raw materials include silicon, magnesium, rare earth elements, calcium, aluminum, and boron.

[0008] Furthermore, the proportions of each raw material contained in the spheroidizing agent are 40-50 parts silicon, 5-8 parts magnesium, 0.5-2 parts rare earth elements, 0.8-2 parts calcium, 0.3-1 part aluminum, and <40 ppm parts boron.

[0009] Furthermore, the proportions of each raw material contained in the spheroidizing agent are 40 parts silicon, 5 parts magnesium, 0.5 parts rare earth elements, 0.8 parts calcium, 0.3 parts aluminum, and <40 ppm boron.

[0010] Furthermore, the proportions of each raw material contained in the spheroidizing agent are 50 parts silicon, 8 parts magnesium, 2 parts rare earth elements, 2 parts calcium, 1 part aluminum, and boron <40 ppm. [Effects of the Invention]

[0011] The above configuration of the present invention provides at least the following beneficial effects. By employing the present invention's method for producing spheroidizing agents, low-boron spheroidizing agents with a boron content of 40 ppm or less can be manufactured. As a result of many years of research, it has been found that the raw materials used in the production of spheroidizing agents do not affect the increase in boron content. However, in the smelting furnaces used in the manufacturing process, current smelting furnaces use a mixture of ordinary materials (non-neutral materials) and boric acid adhesive. Therefore, the boron elements contained in the furnace lining are mixed into the raw materials and refined together during the process of smelting the spheroidizing agent raw materials using ordinary smelting furnaces, thereby increasing the boron content in the spheroidizing agent. In the present invention, the smelting furnace material is improved, specifically by changing the smelting furnace material to a neutral material with a pH of 7, and by mixing the smelting furnace material with an adhesive containing boric acid to cause a chemical reaction, thereby reducing the boron element in the adhesive containing boric acid. Subsequently, when the raw materials for the spheroidizing agent are smelted again using the smelting furnace, the boron content in the raw materials will not increase. Therefore, by changing the smelting furnace material and then manufacturing the spheroidizing agent using the process of the present invention, a low-boron spheroidizing agent with a boron content of 40 ppm or less can be manufactured. [Brief explanation of the drawing]

[0012] [Figure 1] This is a metallographic image of a low-boron spheroidizing agent produced by the present invention for clamp applications, with a boron content of 0.004%, in an uncorroded state. [Figure 2] This is a metallographic image of a low-boron spheroidizing agent manufactured according to the present invention for clamp applications, with a boron content of 0.007%, in an uncorroded state. [Figure 3] This image shows the metallographic structure of a low-boron spheroidizing agent produced according to the present invention for clamp applications, with a boron content of 0.004%, in a corroded state. [Figure 4] This image shows the metallographic structure of a low-boron spheroidizing agent produced according to the present invention for clamp applications, with a boron content of 0.007%, in a corroded state. [Modes for carrying out the invention]

[0013] The technical configurations of embodiments of the present invention will be described clearly and completely below, in conjunction with the drawings of the embodiments. Those skilled in the art should understand that the embodiments described below are only a part of the embodiments of this disclosure, and not all embodiments. All other embodiments that those skilled in the art can obtain without creative work based on the embodiments of the present invention are within the scope of the protection of the present invention.

[0014] By referring to the drawings while reading the following detailed description, the above and other objects, features, and advantages of exemplary embodiments of the present invention will be easily understood. The drawings illustrate and non-limiting embodiments of the present invention, and the same or corresponding symbols represent the same or corresponding parts. [Examples]

[0015] Example 1 of the method for producing the low-boron spheroidizing agent provided by the present invention is as follows. A method for preparing a low-boron spheroidizing agent, Mix various raw materials in a certain proportion. Here, the required raw materials include magnesium ingots, metallic calcium, ferrosilicon, iron scrap, rare earths, aluminum, etc. Step 1 is to blend and mix them by an automatic batching system. Step 2 is to transport the prepared raw materials into a smelting furnace by a conveying system for smelting. During the process of smelting the raw materials in the smelting furnace, step 3 is to continuously measure and monitor the temperature inside the furnace. After smelting is completed, step 4 is to cast and form ingots. After the ingot forming is completed, step 5 is to timely cool it using a sealed type oxygen-free rapid condensation device to reduce the ineffective magnesium in the metal ingot, make the quality of the product more stable, and easier to manage. After the metal ingot is cooled, step 6 is to use a pulverizing device to pulverize it to a certain particle size. Specifically, it can be pulverized to a specific particle size according to the needs of customers. After pulverization is completed, step 7 is to inspect to ensure the quality of the product. After inspection is completed, it includes step 8 of storing the products batch by batch until they are used.

[0016] Furthermore, in order to prevent a large amount of boron from being contained in the smelting furnace, the preparation method of the smelting furnace is as follows. (1) First, mix the smelting furnace materials and an adhesive. (2) Construct an inner lining in the furnace. (3) Accelerate the curing with carbon dioxide for 15 minutes. (4) Dry the furnace body for 6 - 8 hours.

[0017] The material of the smelting furnace is a neutral material, and the pH value of the neutral material is 7.

[0018] The elements contained in the spheroidizing agent prepared using the above various raw materials include silicon, magnesium, rare earths, calcium, aluminum, and boron.

[0019] <000The proportions of each raw material contained in the spheroidizing agent are as follows: silicon 40 parts, magnesium 5 parts, rare earth elements 0.5 parts, calcium 0.8 parts, aluminum 0.3 parts, and boron <40 ppm parts.

[0020] The applications of the low-boron spheroidizing agent produced using the above manufacturing method and raw materials in clamps are as follows: Figure 1 shows the metallographic image of the clamp in its uncorroded state when the boron content is 0.004%. Figure 2 shows the metallographic image of the clamp in its uncorroded state when the boron content is 0.007%. Figure 3 shows the metallographic image of a clamp in a corroded state with a boron content of 0.004%. Figure 4 shows the metallographic image of a clamp in a corroded state with a boron content of 0.007%.

[0021] Furthermore, Table 1 below is an analysis table of graphite morphologies in ductile cast iron treated with spheroidizing agents of different boron content.

[0022] [Table 1]

[0023] Table 2 below shows the tensile strengths of ductile cast iron treated with spheroidizing agents of different boron content.

[0024] [Table 2]

[0025] Table 3 below shows the elongation of ductile cast iron treated with spheroidizing agents of different boron content.

[0026] [Table 3]

[0027] Table 4 below shows the hardness of ductile cast iron treated with spheroidizing agents of different boron content.

[0028] [Table 4]

[0029] Table 5 below shows the impact energies of ductile cast iron treated with spheroidizing agents of different boron content.

[0030] [Table 5]

[0031] By adopting the manufacturing method and raw material blending ratio of this invention, a low-boron spheroidizing agent with a boron content of 40 ppm or less can be produced, and good effects can be obtained in actual applications using this low-boron spheroidizing agent. At the same time, it can meet market needs. [Examples]

[0032] Example 2 of the method for producing the low-boron spheroidizing agent provided by the present invention is as follows. The proportions of each raw material contained in the spheroidizing agent are as follows: silicon 50 parts, magnesium 8 parts, rare earth elements 2 parts, calcium 2 parts, aluminum 1 part, and boron <40 ppm parts. [Examples]

[0033] Example 3 of the method for producing the low-boron spheroidizing agent provided by the present invention is as follows. The proportions of each raw material contained in the spheroidizing agent are as follows: silicon 48 parts, magnesium 7 parts, rare earth elements 1 part, calcium 1 part, aluminum 0.8 parts, and boron <40 ppm.

[0034] The above describes preferred embodiments of the present invention. Although the present invention has been described in detail above by combining the drawings and embodiments, those skilled in the art will understand that multiple specific embodiments can be formed by changing various specific parameters of the above embodiments without departing from the spirit of the present invention, and that all of these will fall within the common range of variation of the present invention. Therefore, we will not describe them in detail here.

Claims

1. Step 1 involves mixing various raw materials in a fixed proportion, where the required raw materials include magnesium ingots, metallic calcium, ferrosilicon, iron scrap, rare earth elements, and aluminum, and blending them using an automated batching system. To prevent excess boron from being present in the smelting furnace, a lining layer is constructed inside the smelting furnace by mixing the smelting furnace material and adhesive, and then the lining is cured using carbon dioxide for 15 minutes, followed by drying the furnace body for 6 to 8 hours in preparation step 2 of the smelting furnace. Step 3 involves transporting the blended raw materials into the smelting furnace by a transport system and smelting them, and Step 4 involves continuously measuring and monitoring the temperature inside the furnace during the process of smelting the raw materials in the smelting furnace. Step 5 involves casting and ingot formation after the smelting process is complete. Step 6 involves reducing the magnesium content in the metal ingot by cooling it in a timely manner using a sealed oxygen-free rapid condensation apparatus after the ingot formation is complete. Step 7 involves crushing the metal ingot to a specific particle size using a crushing device after cooling, specifically, the particle size can be crushed according to customer needs. Step 8 involves inspecting the product after grinding is complete to ensure its quality, Step 9 includes storing the products in batches after inspection is complete until use. A method for preparing a low-boron spheroidizing agent, characterized by changing the smelting furnace material to a neutral material with a pH of 7, mixing the smelting furnace material with an adhesive containing boric acid to cause a chemical reaction, thereby reducing the boron element in the adhesive containing boric acid to 40 ppm or less.

2. The method for preparing a low-boron spheroidizing agent according to claim 1, characterized in that the elements contained in the spheroidizing agent prepared using the various raw materials mentioned above include silicon, magnesium, rare earth elements, calcium, aluminum, and boron.

3. The method for preparing a low-boron spheroidizing agent according to claim 2, characterized in that the parts of each raw material contained in the spheroidizing agent are 40 to 50 parts of silicon, 5 to 8 parts of magnesium, 0.5 to 2 parts of rare earth elements, 0.8 to 2 parts of calcium, 0.3 to 1 part of aluminum, and boron < 40 ppm.

4. The method for preparing a low-boron spheroidizing agent according to claim 3, characterized in that the parts of each raw material contained in the spheroidizing agent are 40 parts silicon, 5 parts magnesium, 0.5 parts rare earth elements, 0.8 parts calcium, 0.3 parts aluminum, and boron < 40 ppm.

5. The method for preparing a low-boron spheroidizing agent according to claim 3, characterized in that the parts of each raw material contained in the spheroidizing agent are 50 parts of silicon, 8 parts of magnesium, 2 parts of rare earth elements, 2 parts of calcium, 1 part of aluminum, and boron < 40 ppm.

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