Special cast ball for beneficiation and grinding of lithium ore and processing technology thereof

Abstract

The application discloses a kind of lithium ore beneficiation grinding special casting ball and its processing technology, the casting ball includes following chemical components according to weight percentage: C:2.1-2.7%, Si:0.8-1.5%, Mn:0.6-1.0%, Cr:10-13%, V:0.1-0.3%, Ti:0.05-0.2%, B:0.03-0.08%, S:≤0.05%, P:≤0.08%, the balance is Fe and inevitable impurities;Wherein, the weight ratio of the sum of Ti and V and B is greater than 6 and less than 12.The lithium ore beneficiation grinding special casting ball and its processing technology proposed in the application, the casting ball has the advantages of high hardness, low abrasion, strong corrosion resistance, good wear resistance and the like, which can effectively meet the discharge requirements after lithium ore beneficiation grinding.

Description

Technical Field

[0001] This invention belongs to the field of abrasive materials technology, and in particular relates to a special casting ball for lithium ore beneficiation and grinding and its processing technology. Background Technology

[0002] Lithium is hailed as the "new energy metal of the century" and a "key element driving the world forward." It also has wide applications in glass, ceramics, metallurgy, lubricants, and the nuclear industry. Lithium resources are mainly found in granite pegmatite deposits and salt lake brine deposits. However, large-scale industrial production of lithium from salt lake brine has not yet been achieved. Currently, extracting lithium from lithium minerals remains the primary method, with spodumene being the most important lithium mineral resource. Flotation is the most widely used method for separating spodumene, but current research and production practices in spodumene flotation mainly focus on flotation reagents and their mechanisms of action, with relatively little research on spodumene grinding processes. Appropriate grinding particle size, especially the particle size distribution of spodumene minerals, is a crucial factor affecting the efficiency of spodumene flotation and subsequent lithium extraction.

[0003] The grinding particle size of lithium ore depends on the efficiency of grinding the raw lithium ore into a ball mill after crushing. Appropriate selection of cast balls is crucial for achieving a more uniform and finer output particle size. Currently, various grinding balls and grinding sections made from high-chromium cast iron, low-chromium cast iron, and low-silicon medium-chromium cast iron, specifically designed for lithium ore beneficiation and grinding, exhibit poor wear resistance and high abrasion consumption, failing to meet the requirements for lithium ore beneficiation and grinding. For instance, low-chromium white cast iron grinding balls, when used in lithium ore ball mills, generally have a breakage rate exceeding 3% (sometimes even exceeding 5% in wet grinding), along with high abrasion consumption (around 1.59 kg / t of ore), resulting in low grinding efficiency and severely impacting the normal production and economic benefits of the ball mill. While ordinary high-chromium white cast iron grinding balls offer improved performance compared to low-chromium white cast iron grinding balls in lithium ore ball mills, their poor wet corrosion resistance and low cost-effectiveness hinder their widespread application. Although the breakage rate of standard medium-carbon low-alloy steel forged balls is low, their wear is still relatively high. Especially given the complex and tight supply of scrap steel in my country, the production of standard medium-carbon low-alloy steel forged balls still faces the problem of poor cost-effectiveness, making mass production difficult in my country. Summary of the Invention

[0004] Based on the above-mentioned technical problems, this invention proposes a special cast ball for lithium ore beneficiation and grinding and its processing technology. The cast ball has the advantages of high hardness, low wear, strong corrosion resistance and good wear resistance, which can effectively meet the output requirements of lithium ore beneficiation and grinding.

[0005] This invention proposes a special casting ball for lithium ore beneficiation and grinding, wherein the casting ball comprises the following chemical components by weight percentage:

[0006] C: 2.1-2.7%, Si: 0.8-1.5%, Mn: 0.6-1.0%, Cr: 10-13%, V: 0.1-0.3%, Ti: 0.05-0.2%, B: 0.03-0.08%, S: ≤0.05%, P: ≤0.08%, with the balance being Fe and unavoidable impurities;

[0007] The ratio of the sum of the weights of Ti and V to the weight of B is greater than 6 and less than 12.

[0008] The components and their contents are optimized in this invention through the following methods:

[0009] C: Carbon is the main element affecting the hardness and wear resistance of cast balls. A high carbon content results in a large number of carbides in the microstructure, high matrix hardness, and good wear resistance. However, if its content exceeds 2.7%, coarse flaky carbides will be produced, making the material hard and brittle. Moreover, because coarse flaky carbides are easy to break and peel off, the wear resistance will decrease. If its content is less than 2.1%, the number of eutectic carbides will decrease, the matrix hardness will decrease, and the wear resistance will also decrease. Therefore, the carbon content should be selected between 2.1% and 2.7%.

[0010] Si: A certain amount of silicon acts as a deoxidizer and is also beneficial to fluidity. Higher silicon content is conducive to the formation of troostite structure. Moreover, after dissolving in the matrix, higher silicon content increases the electrode potential of the matrix and improves corrosion resistance. At the same time, in cast balls, the number of silicides increases with the increase of silicon content, and the hardness and wear resistance also increase. However, when the silicon content is greater than 1.5%, the toughness decreases significantly, while too low a silicon content is not conducive to the formation of troostite structure. Therefore, the silicon content should be selected between 0.8% and 1.5%.

[0011] Mn: Manganese is an element that forms austenite and also plays a role in the formation of carbides. Excessive manganese will cause austenite to appear in the microstructure. Austenite microstructure is not suitable for grinding balls because austenite grinding balls will cause a lot of breakage and spalling in both dry and wet grinding. However, since manganese is used for deoxidation and desulfurization, it is advisable to select a manganese content of 0.6-1.0%.

[0012] Cr: Chromium is a carbide-forming element. In addition to combining with carbon to form carbides, the rest of chromium dissolves in the matrix, thereby increasing the electrode potential of the matrix and which is beneficial for corrosion resistance. If its content is less than 10%, M3C type carbides may form, which will reduce both hardness and toughness. If its content is greater than 13%, the number of carbides increases significantly during crystallization, which will significantly reduce toughness. At the same time, the hardness of the matrix will decrease due to the reduced carbon content, thus reducing wear resistance. Therefore, the chromium content should be selected between 10-13%.

[0013] V, Ti, B: Vanadium, titanium, and boron are all trace alloying elements. They can form carbon oxides with high hardness, which are dispersed in the matrix, which is beneficial to improving the microhardness and wear resistance of the matrix, and also beneficial to the refinement of grains.

[0014] S and P: Sulfur and phosphorus are unavoidable trace impurities, and the lower their content, the better. In order to ensure the hardness and wear resistance of the cast balls, the phosphorus content should be controlled below 0.08% and the sulfur content should be controlled below 0.05%.

[0015] As previously known, V, Ti, and B are all trace alloying elements. They can form carbonitrides with high hardness. When dispersed in the matrix, they are beneficial to improving the microhardness and wear resistance of the matrix, and also beneficial to grain refinement. In this invention, when the weight ratio of the sum of Ti and V to B is controlled to be greater than 6 and less than 12, this ratio control allows the cast balls of this invention to achieve the effect of improving hardness and toughness without the need for additional inoculants.

[0016] Preferably, the cast balls further comprise, by weight percentage: Mo: 0.05-0.2%, Cu: 0.03-0.08%.

[0017] Mo: The main function of molybdenum is to refine the matrix, refine carbides, increase the electrode potential of the matrix, and improve corrosion resistance. Under metal mold casting conditions, its addition of 0.05-0.2% can have a significant effect.

[0018] Cu: Copper is an austenite-forming element. Its main function is to increase the electrode potential of the matrix and improve corrosion resistance. Under the casting conditions of this invention, its addition amount is preferably selected to be 0.03-0.08%.

[0019] Preferably, the weight ratio of Mo to Cu is greater than 2 and less than 4.

[0020] In this invention, the strengthening effect of Mo and Cu on the cast balls is mainly reflected in the change of matrix structure. Mo and Cu entering the matrix can effectively improve the hardenability of the cast balls. By strictly controlling the weight ratio of Mo and Cu to be greater than 2 and less than 4, pearlitic cast balls can be obtained, thereby greatly improving the hardness and impact toughness of the cast balls.

[0021] This invention also proposes a processing technology for casting balls specifically for lithium ore beneficiation and grinding, comprising the following steps:

[0022] S1. After heating and melting scrap steel, ferrochrome, and vanadium-titanium pig iron, ferrosilicon, ferromanganese, copper, ferromolybdenum, and ferroboron are added. The temperature is raised to 1500-1540℃, and samples are taken for chemical composition analysis. The weight percentage of each component is controlled as follows: C: 2.1-2.7%, Si: 0.8-1.5%, Mn: 0.6-1.0%, Cr: 10-13%, V: 0.1-0.3%, Ti: 0.05-0.2%, B: 0.03-0.08%, Mo: 0.05-0.2%, Cu: 0.03-0.08%, S: ≤0.05%, P: ≤0.08%, with the balance being Fe and unavoidable impurities. The temperature is further raised to 1550-1570℃, and a deoxidizer is added for deoxidation to obtain molten iron.

[0023] S2. After the molten iron obtained in step S1 is taken out of the furnace, it is heated to 1600-1650℃, and the molten iron is subjected to a modification treatment by the ladle pouring method to obtain modified molten iron.

[0024] S3. Pour the modified molten iron obtained in step S2 into the mold to obtain the cast ball billet;

[0025] S4. The cast ball blank obtained in step S3 is quenched and tempered to obtain the cast ball for lithium ore beneficiation and grinding.

[0026] Preferably, in step S1, the deoxidizer is industrial pure aluminum;

[0027] Preferably, the amount of pure aluminum used is 0.04-0.1 wt% of the weight of the molten iron.

[0028] Preferably, in step S2, the modification treatment includes: placing the modifier at the bottom of the molten iron ladle using a flushing method, and using the impact force of the molten iron during tapping to fully stir it;

[0029] Preferably, the modifier includes chromium carbide, ferrosilicon alloy, and rare earth magnesium ferrosilicon alloy;

[0030] Preferably, the weight ratio of chromium carbide, ferrosilicon alloy, and rare earth magnesium ferrosilicon alloy is 1:3-4:0.1-0.2;

[0031] Preferably, the silicon weight percentage in the ferrosilicon alloy is 40-50%, the rare earth weight percentage in the rare earth magnesium ferrosilicon alloy is 6-10%, and the magnesium weight percentage is 5-8%.

[0032] Preferably, in step S2, the amount of the modifier is 0.1-0.5 wt% of the weight of the molten iron.

[0033] Preferably, in step S3, the pouring temperature of the molten iron is 1480-1520℃.

[0034] Preferably, in step S4, the quenching process includes: heating the cast ball blank to 960-980℃ and holding it at that temperature for 2-3 hours, and then immersing it in quenching oil at 200-300℃ for quenching.

[0035] Preferably, in step S4, the tempering treatment includes isothermal tempering the quenched cast ball blank at 380-420℃ for 4-6 hours.

[0036] The beneficial effects of this invention are:

[0037] (1) The present invention provides a special casting ball for lithium ore beneficiation and grinding. Through composition optimization design, trace alloying elements such as V, Ti and B are added to form carbon oxide with high hardness, which is dispersed in the matrix, which is beneficial to improve the microhardness and wear resistance of the matrix. At the same time, trace elements such as Mo and Cu are added and the optimal ratio between the two is controlled to control the microstructure, so as to achieve the purpose of casting ball having good wear resistance and comprehensive mechanical properties.

[0038] (2) The present invention provides a processing technology for a special casting ball for lithium ore beneficiation and grinding. Through the modification treatment process of the in-package modifier, the nucleation points of the casting ball before solidification are effectively increased, the grain size of the cast state is refined, the morphology and distribution of the wear-resistant phase eutectic carbide are improved, and the wear resistance and corrosion resistance of the matrix structure are improved.

[0039] (3) The cast ball products obtained by the present invention have uniform hardness inside and outside, no shrinkage cavities or shrinkage porosity on the surface, and have the advantages of high hardness, low wear, strong corrosion resistance and good wear resistance. At the same time, it improves the production efficiency of ball mill, meets the discharge requirements after lithium ore beneficiation and grinding, and is suitable for use in various working conditions. Detailed Implementation

[0040] The present invention will now be described in detail through specific embodiments. However, these embodiments are clearly provided for illustrative purposes and are not intended to limit the scope of the present invention.

[0041] Example 1

[0042] A special casting ball for grinding lithium ore beneficiation comprises the following chemical composition by weight percentage: C: 2.43%, Si: 1.16%, Mn: 0.78%, Cr: 11.62%, V: 0.18%, Ti: 0.13%, B: 0.05%, Mo: 0.11%, Cu: 0.04%, S: 0.02%, P: 0.05%, with the balance being Fe and unavoidable impurities; wherein the weight ratio of the sum of Ti and V to B is 6.2, and the weight ratio of Mo to Cu is 2.8.

[0043] The processing technology for these lithium ore beneficiation and grinding special casting balls includes:

[0044] S1. Scrap steel, ferrochrome, and vanadium-titanium pig iron are added to a medium-frequency induction furnace and heated to melt. Then, ferrosilicon, ferromanganese, copper, ferromolybdenum, and ferroboron are added. After heating to 1520℃, samples are taken for chemical composition analysis, and the weight percentages of each component are controlled as follows: C: 2.43%, Si: 1.16%, Mn: 0.78%, Cr: 11.62%, V: 0.18%, Ti: 0.13%, B: 0.05%, Mo: 0.11%, Cu: 0.04%, S: 0.02%, P: 0.05%, with the balance being Fe and unavoidable impurities. The temperature is further increased to 1560℃, and then industrial pure aluminum is added for deoxidation. The amount of pure aluminum used is 0.07 wt% of the weight of the molten iron, thus obtaining molten iron.

[0045] S2. After the molten iron obtained in step S1 is tapped from the furnace, it is heated to 1630°C. The modifier is placed at the bottom of the ladle using the pouring method. The modifier is thoroughly stirred by the impact force of the molten iron during tapping to complete the modification treatment. The modifier is obtained by melting and mixing chromium carbide, ferrosilicon alloy and rare earth magnesium ferrosilicon alloy in a weight ratio of 1:3.5:0.15. The weight percentage of silicon in the ferrosilicon alloy is 45%, the weight percentage of rare earth in the rare earth magnesium ferrosilicon alloy is 8%, and the weight percentage of magnesium is 6%. The amount of modifier is 0.3 wt% of the weight of the molten iron, thus obtaining the modified molten iron.

[0046] S3. Pour the modified molten iron obtained in step S2 into the mold at a pouring temperature of 1500℃ to obtain a cast ball billet.

[0047] S4. After heating the cast ball blank obtained in step S3 to 970°C and holding it at that temperature for 2.5 hours, immerse it in quenching oil at 250°C for quenching. Then, temper the quenched cast ball blank isothermally at 400°C for 5 hours to obtain the cast ball for lithium ore beneficiation and grinding.

[0048] Example 2

[0049] A special casting ball for grinding lithium ore beneficiation comprises the following chemical composition by weight percentage: C: 2.12%, Si: 1.47%, Mn: 0.65%, Cr: 12.88%, V: 0.11%, Ti: 0.19%, B: 0.03%, Mo: 0.16%, Cu: 0.04%, S: 0.01%, P: 0.04%, with the balance being Fe and unavoidable impurities; wherein the weight ratio of the sum of Ti and V to B is 10.0, and the weight ratio of Mo to Cu is 4.0.

[0050] The processing technology for these lithium ore beneficiation and grinding special casting balls includes:

[0051] S1. Scrap steel, ferrochrome, and vanadium-titanium pig iron are added to a medium-frequency induction furnace and heated to melt. Then, ferrosilicon, ferromanganese, copper, ferromolybdenum, and ferroboron are added. After heating to 1500℃, samples are taken for chemical composition analysis, and the weight percentages of each component are controlled as follows: C: 2.12%, Si: 1.47%, Mn: 0.65%, Cr: 12.88%, V: 0.11%, Ti: 0.19%, B: 0.03%, Mo: 0.16%, Cu: 0.04%, S: 0.01%, P: 0.04%, with the balance being Fe and unavoidable impurities. The temperature is further increased to 1570℃, and then industrial pure aluminum is added for deoxidation. The amount of pure aluminum used is 0.04 wt% of the weight of the molten iron, thus obtaining molten iron.

[0052] S2. After the molten iron obtained in step S1 is tapped from the furnace, it is heated to 1650°C. The modifier is placed at the bottom of the ladle using the pouring method. The modifier is thoroughly stirred by the impact force of the molten iron during tapping to complete the modification treatment. The modifier is obtained by melting and mixing chromium carbide, ferrosilicon alloy and rare earth magnesium ferrosilicon alloy in a weight ratio of 1:3.5:0.15. The weight percentage of silicon in the ferrosilicon alloy is 45%, the weight percentage of rare earth in the rare earth magnesium ferrosilicon alloy is 8%, and the weight percentage of magnesium is 6%. The amount of modifier is 0.1 wt% of the weight of the molten iron, thus obtaining the modified molten iron.

[0053] S3. Pour the modified molten iron obtained in step S2 into the mold at a pouring temperature of 1520℃ to obtain a cast ball billet.

[0054] S4. After heating the cast ball blank obtained in step S3 to 960°C and holding it for 3 hours, immerse it in quenching oil at 200°C for quenching. Then, temper the quenched cast ball blank isothermally at 420°C for 4 hours to obtain the cast ball for lithium ore beneficiation and grinding.

[0055] Example 3

[0056] A special casting ball for grinding lithium ore beneficiation comprises the following chemical composition by weight percentage: C: 2.67%, Si: 0.83%, Mn: 0.97%, Cr: 10.56%, V: 0.29%, Ti: 0.08%, B: 0.06%, Mo: 0.09%, Cu: 0.04%, S: 0.02%, P: 0.05%, with the balance being Fe and unavoidable impurities; wherein the weight ratio of the sum of Ti and V to B is 6.2, and the weight ratio of Mo to Cu is 2.3.

[0057] The processing technology for these lithium ore beneficiation and grinding special casting balls includes:

[0058] S1. Scrap steel, ferrochrome, and vanadium-titanium pig iron are added to a medium-frequency induction furnace and heated to melt. Then, ferrosilicon, ferromanganese, copper, ferromolybdenum, and ferroboron are added. After heating to 1540℃, samples are taken for chemical composition analysis, and the weight percentages of each component are controlled as follows: C: 2.67%, Si: 0.83%, Mn: 0.97%, Cr: 10.56%, V: 0.29%, Ti: 0.08%, B: 0.06%, Mo: 0.09%, Cu: 0.04%, S: 0.02%, P: 0.05%, with the balance being Fe and unavoidable impurities. The temperature is further increased to 1550℃, and then industrial pure aluminum is added for deoxidation. The amount of pure aluminum used is 0.1 wt% of the weight of the molten iron, thus obtaining molten iron.

[0059] S2. After the molten iron obtained in step S1 is tapped from the furnace, it is heated to 1600℃. The modifier is placed at the bottom of the ladle using the pouring method. The modifier is thoroughly stirred by the impact force of the molten iron during tapping to complete the modification treatment. The modifier is obtained by melting and mixing chromium carbide, ferrosilicon alloy and rare earth magnesium ferrosilicon alloy in a weight ratio of 1:3.5:0.15. The weight percentage of silicon in the ferrosilicon alloy is 45%, the weight percentage of rare earth in the rare earth magnesium ferrosilicon alloy is 8%, and the weight percentage of magnesium is 6%. The amount of modifier is 0.5 wt% of the weight of the molten iron, thus obtaining the modified molten iron.

[0060] S3. Pour the modified molten iron obtained in step S2 into the mold at a pouring temperature of 1480℃ to obtain a cast ball billet.

[0061] S4. After heating the cast ball blank obtained in step S3 to 980°C and holding it at that temperature for 2 hours, immerse it in quenching oil at 300°C for quenching. Then, temper the quenched cast ball blank isothermally at 380°C for 6 hours to obtain the cast ball for lithium ore beneficiation and grinding.

[0062] Example 4

[0063] A special casting ball for grinding lithium ore beneficiation comprises the following chemical composition by weight percentage: C: 2.45%, Si: 1.17%, Mn: 0.80%, Cr: 11.57%, V: 0.16%, Ti: 0.11%, B: 0.05%, Mo: 0.12%, Cu: 0.04%, S: 0.01%, P: 0.04%, with the balance being Fe and unavoidable impurities; wherein the weight ratio of the sum of Ti and V to B is 5.4, and the weight ratio of Mo to Cu is 3.0.

[0064] The processing technology for these lithium ore beneficiation and grinding special casting balls includes:

[0065] S1. Scrap steel, ferrochrome, and vanadium-titanium pig iron are added to a medium-frequency induction furnace and heated to melt. Then, ferrosilicon, ferromanganese, copper, ferromolybdenum, and ferroboron are added. After heating to 1520℃, samples are taken for chemical composition analysis, and the weight percentages of each component are controlled as follows: C: 2.45%, Si: 1.17%, Mn: 0.80%, Cr: 11.57%, V: 0.16%, Ti: 0.11%, B: 0.05%, Mo: 0.12%, Cu: 0.04%, S: 0.01%, P: 0.04%, with the balance being Fe and unavoidable impurities. The temperature is further increased to 1560℃, and then industrial pure aluminum is added for deoxidation. The amount of pure aluminum used is 0.07 wt% of the weight of the molten iron, thus obtaining molten iron.

[0066] S2. After the molten iron obtained in step S1 is tapped from the furnace, it is heated to 1630°C. The modifier is placed at the bottom of the ladle using the pouring method. The modifier is thoroughly stirred by the impact force of the molten iron during tapping to complete the modification treatment. The modifier is obtained by melting and mixing chromium carbide, ferrosilicon alloy and rare earth magnesium ferrosilicon alloy in a weight ratio of 1:3.5:0.15. The weight percentage of silicon in the ferrosilicon alloy is 45%, the weight percentage of rare earth in the rare earth magnesium ferrosilicon alloy is 8%, and the weight percentage of magnesium is 6%. The amount of modifier is 0.3 wt% of the weight of the molten iron, thus obtaining the modified molten iron.

[0067] S3. Pour the modified molten iron obtained in step S2 into the mold at a pouring temperature of 1500℃ to obtain a cast ball billet.

[0068] S4. After heating the cast ball blank obtained in step S3 to 970°C and holding it at that temperature for 2.5 hours, immerse it in quenching oil at 250°C for quenching. Then, temper the quenched cast ball blank isothermally at 400°C for 5 hours to obtain the cast ball for lithium ore beneficiation and grinding.

[0069] Example 5

[0070] A special casting ball for grinding lithium ore beneficiation comprises the following chemical composition by weight percentage: C: 2.41%, Si: 1.15%, Mn: 0.76%, Cr: 12.01%, V: 0.19%, Ti: 0.15%, B: 0.05%, Mo: 0.10%, Cu: 0.06%, S: 0.02%, P: 0.04%, with the balance being Fe and unavoidable impurities; wherein the weight ratio of the sum of Ti and V to B is 6.8, and the weight ratio of Mo to Cu is 1.7.

[0071] The processing technology for these lithium ore beneficiation and grinding special casting balls includes:

[0072] S1. Scrap steel, ferrochrome, and vanadium-titanium pig iron are added to a medium-frequency induction furnace and heated to melt. Then, ferrosilicon, ferromanganese, copper, ferromolybdenum, and ferroboron are added. After heating to 1520℃, samples are taken for chemical composition analysis, and the weight percentages of each component are controlled as follows: C: 2.41%, Si: 1.15%, Mn: 0.76%, Cr: 12.01%, V: 0.19%, Ti: 0.15%, B: 0.05%, Mo: 0.10%, Cu: 0.06%, S: 0.02%, P: 0.04%, with the balance being Fe and unavoidable impurities. The temperature is further increased to 1560℃, and then industrial pure aluminum is added for deoxidation. The amount of pure aluminum used is 0.07 wt% of the weight of the molten iron, thus obtaining molten iron.

[0073] S2. After the molten iron obtained in step S1 is tapped from the furnace, it is heated to 1630°C. The modifier is placed at the bottom of the ladle using the pouring method. The modifier is thoroughly stirred by the impact force of the molten iron during tapping to complete the modification treatment. The modifier is obtained by melting and mixing chromium carbide, ferrosilicon alloy and rare earth magnesium ferrosilicon alloy in a weight ratio of 1:3.5:0.15. The weight percentage of silicon in the ferrosilicon alloy is 45%, the weight percentage of rare earth in the rare earth magnesium ferrosilicon alloy is 8%, and the weight percentage of magnesium is 6%. The amount of modifier is 0.3 wt% of the weight of the molten iron, thus obtaining the modified molten iron.

[0074] S3. Pour the modified molten iron obtained in step S2 into the mold at a pouring temperature of 1500℃ to obtain a cast ball billet.

[0075] S4. After heating the cast ball blank obtained in step S3 to 970°C and holding it at that temperature for 2.5 hours, immerse it in quenching oil at 250°C for quenching. Then, temper the quenched cast ball blank isothermally at 400°C for 5 hours to obtain the cast ball for lithium ore beneficiation and grinding.

[0076] Experimental test:

[0077] The cast balls obtained in the examples were tested. The hardness of the cast balls was tested using an HR-150A Rockwell hardness tester, and the room temperature impact toughness was tested using a JB-30 impact tester. The number of drop tests with H=3.5m was also tested. The results are shown in Table 1 below:

[0078] Table 1 Performance test results of the cast balls obtained in the examples

[0079]

[0080] As can be seen from the table above, the cast balls described in this invention have good comprehensive mechanical properties and excellent wear resistance.

[0081] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A special cast ball for grinding lithium ore, characterized in that, The cast balls comprise the following chemical components by weight percentage: C: 2.1-2.7%, Si: 0.8-1.5%, Mn: 0.6-1.0%, Cr: 10-13%, V: 0.1-0.3%, Ti: 0.05-0.2%, B: 0.03-0.08%, S: ≤0.05%, P: ≤0.08%, with the balance being Fe and unavoidable impurities; Among them, the ratio of the sum of the weights of Ti and V to the weight of B is greater than 6 and less than 12; The cast balls also include, by weight percentage: Mo: 0.05-0.2%, Cu: 0.03-0.08%; the weight ratio of Mo to Cu is greater than 2 and less than 4.

2. A processing technology for casting balls specifically for lithium ore beneficiation and grinding, characterized in that, Includes the following steps: S1. After heating and melting scrap steel, ferrochrome, and vanadium-titanium pig iron, ferrosilicon, ferromanganese, copper, ferromolybdenum, and ferroboron are added. The temperature is raised to 1500-1540℃, and samples are taken for chemical composition analysis. The weight percentages of each component are controlled as follows: C: 2.1-2.7%, Si: 0.8-1.5%, Mn: 0.6-1.0%, Cr: 10-13%, V: 0.1-0.3%, Ti: 0.05-0.2%, B: 0.03-0.08%, Mo: 0.05-0.2%, Cu: 0.03-0.08%, S: ≤0.05%, P: ≤0.08%, with the balance being Fe and unavoidable impurities. The weight ratio of the sum of Ti and V to B is greater than 6 and less than 12; the weight ratio of Mo to Cu is greater than 2 and less than 4. The temperature is further raised to 1550-1570℃, and a deoxidizer is added for deoxidation to obtain molten iron. S2. After the molten iron obtained in step S1 is taken out of the furnace, it is heated to 1600-1650℃, and the molten iron is subjected to a modification treatment by the ladle pouring method to obtain modified molten iron. S3. Pour the modified molten iron obtained in step S2 into the mold to obtain the cast ball billet; S4. The cast ball blank obtained in step S3 is quenched and tempered to obtain the cast ball for lithium ore beneficiation and grinding.

3. The processing technology for the special casting balls for lithium ore beneficiation and grinding according to claim 2, characterized in that, In step S1, the deoxidizer is industrial pure aluminum; The amount of pure aluminum used is 0.04-0.1 wt% of the weight of the molten iron.

4. The processing technology for the special casting balls for lithium ore beneficiation and grinding according to claim 2 or 3, characterized in that, In step S2, the modification treatment includes: placing the modifier at the bottom of the molten iron ladle using the flushing method, and using the impact force of the molten iron during tapping to fully stir it; The modifiers include chromium carbide, ferrosilicon alloy, and rare earth magnesium ferrosilicon alloy; the weight ratio of chromium carbide, ferrosilicon alloy, and rare earth magnesium ferrosilicon alloy is 1:3-4:0.1-0.

2. The silicon-iron alloy contains 40-50% silicon by weight, and the rare earth magnesium silicon-iron alloy contains 6-10% rare earth and 5-8% magnesium by weight.

5. The processing technology for the lithium ore beneficiation and grinding special casting balls according to claim 4, characterized in that, In step S2, the amount of the modifier is 0.1-0.5 wt% of the weight of the molten iron.

6. The processing technology for the special casting balls for lithium ore beneficiation and grinding according to claim 2 or 3, characterized in that, In step S3, the pouring temperature of the molten iron is 1480-1520℃.

7. The processing technology for the special casting balls for lithium ore beneficiation and grinding according to claim 2 or 3, characterized in that, In step S4, the quenching process includes: heating the cast ball blank to 960-980℃ and holding it at that temperature for 2-3 hours, then immersing it in quenching oil at 200-300℃ for quenching.

8. The processing technology for the special casting balls for lithium ore beneficiation and grinding according to claim 7, characterized in that, In step S4, the tempering process includes isothermal tempering the quenched cast ball blank at 380-420℃ for 4-6 hours.

Images