A method for preparing a low-boron spheroidizing agent

Abstract

This invention provides a method for preparing a low-boron spheroidizing agent, belonging to the field of spheroidizing agent technology. The method includes the following steps: Step 1: Mixing various raw materials in a certain proportion, wherein the required raw materials include magnesium ingots, metallic calcium, ferrosilicon, scrap steel, rare earth elements, and aluminum, using an automatic batching system; Step 2: Transporting the batched raw materials to a melting furnace via a conveying system for melting; Step 3: During the melting process in the melting furnace, continuously measuring and monitoring the temperature inside the furnace. Using the method described in this application, a low-boron spheroidizing agent with a boron content of less than 40 ppm can be produced.

Description

Technical Field

[0001] This invention relates to the field of spheroidizing agent technology, and specifically to a method for preparing a low-boron spheroidizing agent. Background Technology

[0002] Spheroidizing agents are certain metals or alloys added to molten iron to obtain spheroidal graphite cast iron. In China, ferrosilicon, rare earth, and magnesium spheroidizing agents are commonly used. Production processes for spheroidizing agents include hot remelting and low-silicon shot pressing. Combining the influence of each element in the spheroidizing agent on spheroidization, rationally proportioning and optimizing the production process to improve the quality of ductile iron is a continuous research topic for foundry workers. With customers' increasing demands for product quality, current spheroidizing agents with high boron content are no longer sufficient for the production of special ductile iron. Currently, the boron content in spheroidizing agents on the market is generally above 60 ppm, which cannot meet the requirements for special ductile iron production. Since trace elements in spheroidizing agents have a significant impact on spheroidization quality, such as the effect of boron on graphite and matrix structure, it is essential to control the boron content in the spheroidizing agent. How to produce spheroidizing agents with a boron content below 50 ppm is a technical challenge. Summary of the Invention

[0003] In view of this, the present invention provides a method for preparing a low-boron spheroidizing agent to solve the problem that the prior art cannot produce spheroidizing agents with a concentration of less than 50 ppm.

[0004] To solve the above-mentioned technical problems, the preparation method of the low-boron spheroidizing agent provided by the present invention adopts the following technical solution:

[0005] A method for preparing a low-boron spheroidizing agent includes the following steps:

[0006] Step 1: Mix various raw materials in a certain proportion. The required raw materials include magnesium ingots, metallic calcium, ferrosilicon, scrap steel, rare earth and aluminum, which are mixed by an automatic batching system.

[0007] Step 2: The prepared raw materials are transported to the smelting furnace through a conveyor system for smelting;

[0008] Step 3: During the original smelting process in the smelting furnace, it is necessary to continuously measure and monitor the temperature inside the furnace.

[0009] Step 4: After smelting, the casting and ingot making are carried out;

[0010] Step 5: After the ingot is made, it is cooled in time by using a sealed oxygen-free rapid condensation device, which reduces the ineffective magnesium in the metal ingot and makes the product quality more stable and controllable.

[0011] Step Six: After the metal ingot is cooled, it is crushed using crushing equipment to break it into particles of a certain size. The specific particle size can be crushed according to customer requirements.

[0012] Step 7: After crushing, conduct an inspection to ensure product quality;

[0013] Step 8: After testing, store the product batch for later use.

[0014] Furthermore, to avoid the presence of large amounts of boron in the smelting furnace, the smelting furnace is prepared as follows:

[0015] (1) First, mix the furnace charge and the binder;

[0016] (2) Furnace lining construction;

[0017] (3) Accelerate carbon dioxide hardening for 15 minutes;

[0018] (4) Dry the furnace body for 6-8 hours.

[0019] Furthermore, the smelting furnace is made of a neutral material with a pH value of 7.

[0020] Furthermore, the spheroidizing agent prepared using the above-mentioned raw materials contains the chemical elements silicon, magnesium, rare earth elements, calcium, aluminum, and boron.

[0021] Furthermore, the spheroidizing agent contains the following proportions of each raw material: silicon 40-50 parts, magnesium 5-8 parts, rare earth 0.5-2 parts, calcium 0.8-2 parts, aluminum 0.3-1 parts, and boron <40 ppm.

[0022] Furthermore, the spheroidizing agent contains the following proportions of each raw material: 40 parts silicon, 5 parts magnesium, 0.5 parts rare earth, 0.8 parts calcium, 0.3 parts aluminum, and <40 ppm boron.

[0023] Furthermore, the composition includes 50 parts silicon, 8 parts magnesium, 2 parts rare earth elements, 2 parts calcium, 1 part aluminum, and <40 ppm boron.

[0024] The above-described technical solution of the present invention has at least the following beneficial effects:

[0025] The spheroidizing agent preparation method of this application can produce low-boron spheroidizing agents with a boron content of less than 40 ppm. Extensive research has shown that the raw materials used in the production of the spheroidizing agent do not affect the increase in boron content. However, in the melting furnaces used in the production process, the current melting furnaces use ordinary materials (non-neutral materials) mixed with boric acid binders, resulting in boron content in the furnace lining. Therefore, during the melting of the spheroidizing agent raw materials in ordinary melting furnaces, boron from the furnace lining will be mixed into the raw materials and melted together, thereby increasing the boron content in the spheroidizing agent. This application improves the furnace material by replacing the furnace charge with a neutral material with a pH value of 7. When this furnace charge is mixed with a binder containing boric acid, a chemical reaction occurs, reducing the boron content in the boric acid-containing binder. Consequently, when the raw materials for the spheroidizing agent are smelted in the furnace again, the boron content in the raw materials will not increase. By changing the furnace material and then producing the spheroidizing agent using the process described in this application, a low-boron spheroidizing agent with a boron content of less than 40 ppm can be produced. Attached Figure Description

[0026] The above and other objects, features, and advantages of exemplary embodiments of the present invention will become readily apparent upon reading the following detailed description with reference to the accompanying drawings. In the drawings, several embodiments of the invention are illustrated by way of example and not limitation, and like or corresponding reference numerals denote like or corresponding parts, wherein:

[0027] Figure 1 The image shows the metallographic structure of the low-boron spheroidizing agent of the present invention in the application of clamps with a boron content of 0.004% in the uncorroded state.

[0028] Figure 2 The image shows the metallographic structure of the low-boron spheroidizing agent of the present invention in the application of clamps with a boron content of 0.007% in the uncorroded state.

[0029] Figure 3 The metallographic image shows the low-boron spheroidizing agent of the present invention in a corroded state with a boron content of 0.004% in the application of clamps.

[0030] Figure 4 This is a metallographic image of the low-boron spheroidizing agent of the present invention in the corroded state with a boron content of 0.007% in the application of clamps. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Those skilled in the art should understand that the embodiments described below are only some, not all, of the embodiments disclosed. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0032] Example 1 of the preparation method of the low-boron spheroidizing agent provided by the present invention is as follows:

[0033] A method for preparing a low-boron spheroidizing agent includes the following steps:

[0034] Step 1: Mix various raw materials in a certain proportion. The required raw materials include magnesium ingots, metallic calcium, ferrosilicon, scrap steel, rare earth and aluminum, which are mixed by an automatic batching system.

[0035] Step 2: The prepared raw materials are transported to the smelting furnace through a conveyor system for smelting;

[0036] Step 3: During the original smelting process in the smelting furnace, it is necessary to continuously measure and monitor the temperature inside the furnace.

[0037] Step 4: After smelting, the casting and ingot making are carried out;

[0038] Step 5: After the ingot is made, it is cooled in time by using a sealed oxygen-free rapid condensation device, which reduces the ineffective magnesium in the metal ingot and makes the product quality more stable and controllable.

[0039] Step Six: After the metal ingot is cooled, it is crushed using crushing equipment to break it into particles of a certain size. The specific particle size can be crushed according to customer requirements.

[0040] Step 7: After crushing, conduct an inspection to ensure product quality;

[0041] Step 8: After testing, store the product batch for later use.

[0042] To avoid the presence of large amounts of boron in the smelting furnace, the smelting furnace is prepared as follows:

[0043] (1) First, mix the furnace charge and the binder;

[0044] (2) Furnace lining construction;

[0045] (3) Accelerate carbon dioxide hardening for 15 minutes;

[0046] (4) Dry the furnace body for 6-8 hours.

[0047] The smelting furnace is made of a neutral material with a pH value of 7.

[0048] The spheroidizing agent prepared using the above-mentioned raw materials contains the chemical elements silicon, magnesium, rare earth, calcium, aluminum, and boron.

[0049] The spheroidizing agent contains the following proportions of raw materials: 40 parts silicon, 5 parts magnesium, 0.5 parts rare earth, 0.8 parts calcium, 0.3 parts aluminum, and <40 ppm boron.

[0050] The low-boron spheroidizing agent produced using the above preparation method and raw materials is applied to clamps as follows:

[0051] Metallographic images of the clamp in its uncorroded state with a boron content of 0.004% can be referenced. Figure 1 As shown.

[0052] Metallographic diagram of the clamp in its uncorroded state with a boron content of 0.007% can be referenced. Figure 2 As shown.

[0053] The metallographic diagram of the clamp in the corroded state with a boron content of 0.004% can be referenced. Figure 3 As shown.

[0054] The metallographic diagram of the clamp in the corroded state with a boron content of 0.007% can be referenced. Figure 4 As shown.

[0055] In addition, Table 1 below is an analysis table of graphite morphology in ductile iron treated with spheroidizing agents of different boron contents.

[0056]

[0057] Table 2 below shows the tensile strength of ductile iron treated with spheroidizing agents of different boron contents.

[0058]

[0059] Table 3 below shows the elongation of ductile iron treated with spheroidizing agents of different boron contents.

[0060]

[0061] Table 4 below shows the hardness of ductile iron treated with spheroidizing agents of different boron contents.

[0062]

[0063] Table 5 below shows the impact energy of ductile iron treated with spheroidizing agents of different boron contents.

[0064]

[0065] By employing the preparation method and raw material ratio described in this application, a low-boron spheroidizing agent with a boron content of less than 40 ppm can be produced, and this low-boron spheroidizing agent has also produced good results in practical applications. Simultaneously, it can meet market demand.

[0066] Example 2 of the preparation method of the low-boron spheroidizing agent provided by the present invention is as follows:

[0067] The spheroidizing agent contains the following proportions of raw materials: 50 parts silicon, 8 parts magnesium, 2 parts rare earth, 2 parts calcium, 1 part aluminum, and <40 ppm boron.

[0068] Example 3 of the preparation method of the low-boron spheroidizing agent provided by the present invention is as follows:

[0069] The spheroidizing agent contains the following proportions of raw materials: 48 parts silicon, 7 parts magnesium, 1 part rare earth, 1 part calcium, 0.8 parts aluminum, and <40 ppm boron.

[0070] The above description represents the preferred embodiments of the present invention. It should be noted that the present invention has been described in detail above with reference to the accompanying drawings and embodiments. However, those skilled in the art will understand that, without departing from the spirit of the present invention, various specific parameters in the above embodiments can be changed to form multiple specific embodiments, all of which are common variations of the present invention, and will not be described in detail here.

Claims

1. A method for preparing a low-boron spheroidizing agent, characterized in that: Includes the following steps: Step 1: Mix various raw materials in a certain proportion. The required raw materials include magnesium ingots, metallic calcium, ferrosilicon, scrap steel, rare earth and aluminum, which are mixed by an automatic batching system. Step 2: The prepared raw materials are transported to the smelting furnace through a conveyor system for smelting; Step 3: During the smelting process of the raw materials in the smelting furnace, it is necessary to continuously measure and monitor the temperature inside the furnace. Step 4: After smelting, the casting and ingot making are carried out; Step 5: After the ingot is made, it is cooled in time by using a sealed oxygen-free rapid condensation device, which reduces the ineffective magnesium in the metal ingot and makes the product quality more stable and controllable. Step Six: After the metal ingot is cooled, it is crushed using crushing equipment to break it into particles of a certain size. The specific particle size can be crushed according to customer requirements. Step 7: After crushing, conduct an inspection to ensure product quality; Step 8: After testing, store the product batch for later use. To avoid the presence of large amounts of boron in the smelting furnace, the smelting furnace is prepared as follows: (1) First, mix the furnace charge and the binder; (2) Furnace lining construction; (3) Accelerate carbon dioxide hardening for 15 minutes; (4) Dry the furnace body for 6-8 hours; The smelting furnace is made of a neutral material with a pH value of 7. The adhesive is a boric acid adhesive.

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

3. The method for preparing the low-boron spheroidizing agent according to claim 2, characterized in that: The spheroidizing agent contains the following proportions of raw materials: silicon 40-50 parts, magnesium 5-8 parts, rare earth 0.5-2 parts, calcium 0.8-2 parts, aluminum 0.3-1 parts, and boron <40 ppm.

4. The method for preparing the low-boron spheroidizing agent according to claim 3, characterized in that: The spheroidizing agent contains the following proportions of raw materials: 40 parts silicon, 5 parts magnesium, 0.5 parts rare earth, 0.8 parts calcium, 0.3 parts aluminum, and <40 ppm boron.

5. The method for preparing the low-boron spheroidizing agent according to claim 3, characterized in that: The spheroidizing agent contains the following proportions of raw materials: 50 parts silicon, 8 parts magnesium, 2 parts rare earth, 2 parts calcium, 1 part aluminum, and <40 ppm boron.

Images