A steel for a crusher super wear-resistant conical lining plate and a preparation method thereof

Abstract

The present application relates to a kind of crusher super wear-resistant cone lining plate steel and its preparation method, contains the following components by mass percentage: C:1.30-1.50%, Mn:22-25%, Si:0.35-0.80%, Cr:2.0-2.5%, V:0.1-0.15%, Ti:0.06-0.12%, N:0.05-0.08%, Mo:0.3-0.6%, P≤0.035%, S≤0.015%, the balance is Fe and inevitable impurities.Mass ratio of Mn / C is 16-18, mass ratio of Cr / V is 16-20, and total mass ratio of Cr+Mo≤2.8%.The hardness of steel can reach 289HB, impact toughness can reach 203J / cm 2 , tensile strength can reach 849MPa, reduce the mass addition of Ni, Mo and other elements, greatly reduce cost.

Description

Technical Field

[0001] This invention belongs to the field of wear-resistant steel technology, specifically relating to a steel for ultra-wear-resistant cone liners of crushers and its preparation method. Background Technology

[0002] A cone crusher is a mining machine used for crushing ores. During operation, the ore enters through the feed inlet and is crushed by impact and compression within the crushing chamber formed by the mantle and crushing wall. The cone crusher liner, as a core wear-resistant component, withstands the intense impact, compression, and abrasive wear of the ore over long periods. Especially when processing medium-hard iron ore, the liner must simultaneously meet the requirements of high surface hardness (≥50 HRC) to resist abrasive cutting and excellent impact toughness (≥150 J / cm²). 2 It prevents breakage and has strong work hardening ability, maintaining surface hardness even under low impact conditions. However, traditional high-manganese steel (such as ZGMn13) has inherent defects: low initial hardness (only 18-22 HRC), which prevents sufficient hardening when impact energy in the fine crushing cavity is insufficient, resulting in a sharp drop in wear resistance of more than 30% and a short service life; incomplete dissolution of carbides in the core of thick-walled castings, leaving undissolved carbides during water quenching, which become crack sources; and strong dependence on precious metals, requiring the addition of elements such as Ni and Mo to improve performance, increasing the cost per ton by 8-12%.

[0003] With the increasing size of mining equipment, the service conditions of liners are becoming increasingly stringent. There is an urgent need to develop wear-resistant liners with higher hardness and strength to extend their service life, while reducing product costs is also a pressing issue. Therefore, traditional liner steels are insufficient to meet the requirements of low cost and high performance. There is an urgent need to develop a low-cost, high-strength, and high-hardness liner steel to meet market demands and drive industry development. Summary of the Invention

[0004] This invention provides a steel for ultra-wear-resistant cone liners of crushers and its preparation method, addressing the problems of insufficient hardness, short service life, and high cost of current liner steels. The obtained ultra-wear-resistant cone liner steel for crushers has a grain size controlled at grade 8-10, carbide precipitates smaller than 80 nm, a hardness reaching 289 HB, and an impact toughness reaching 203 J / cm². 2 The tensile strength can reach 849MPa. The steel used for the ultra-wear-resistant cone liner of the crusher has high hardness, high tensile strength and excellent impact toughness. It is alloyed using only Cr, Mo, V and Ti elements, and by optimizing the ratio and proportion of alloying elements, the synergistic effect of the elements is fully utilized, reducing the large addition of elements such as Ni and Mo, and greatly reducing the cost.

[0005] In a first aspect, the present invention relates to a steel for ultra-wear-resistant cone liners for crushers, comprising the following components by mass percentage: C: 1.30-1.50%, Mn: 22-25%, Si: 0.35-0.80%, Cr: 2.0-2.5%, V: 0.1-0.15%, Ti: 0.06-0.12%, N: 0.05-0.08%, Mo: 0.3-0.6%, P≤0.035%, S≤0.015%, with the balance being Fe and unavoidable impurities.

[0006] Preferably, the mass ratio of Mn / C is 16-18, the mass ratio of Cr / V is 16-20, and the total mass percentage of Cr+Mo is ≤2.8%.

[0007] Preferably, the grain size of the steel is grade 8 to 10, and the size of the precipitated carbides in the steel is less than 80 nm.

[0008] Preferably, the steel has a hardness of up to 289 HB and an impact toughness of up to 203 J / cm. 2 Its tensile strength can reach 849 MPa.

[0009] Preferably, the steel for the ultra-wear-resistant cone liner of the crusher contains the following components by mass percentage: C: 1.4%, Mn: 23%, Si: 0.4%, Cr: 2.3%, V: 0.13%, Ti: 0.1%, N: 0.06%, Mo: 0.4%, P≤0.035%, S≤0.015%, with the balance being Fe and unavoidable impurities.

[0010] Secondly, the present invention relates to a method for preparing a steel for an ultra-wear-resistant cone liner for a crusher, comprising the following steps:

[0011] Smelting: The ingredients are prepared according to the chemical composition, and smelting is carried out in an electric arc furnace or a medium-frequency induction furnace. The temperature is controlled at 1600-1650℃ during the smelting process, and deoxidation and desulfurization treatment are carried out.

[0012] Casting: The molten steel is poured into the casting to obtain the casting. The casting temperature is controlled at 1450-1550℃.

[0013] First heat treatment: Heat the casting to 850-880℃ and hold for 2-3 hours, then air cool for the first heat treatment;

[0014] Water quenching: The casting is heated to 1080-1120℃ at a rate of 40-50℃ / h and held at that temperature for a duration t that satisfies: t = 0.018 × a × [1.3 × (C + Si + 0.5Cr + Mo)].

[0015] Where t is the heat preservation time in hours; a is the maximum wall thickness of the liner in mm; and C, Si, Cr, and Mo are the mass fractions of C, Si, Cr, and Mo elements in the steel.

[0016] After heat preservation, water quenching and cooling are performed at a rate ≥50℃ / s; the maximum wall thickness of the liner plate is 40-80mm.

[0017] Second heat treatment: Heat the water-quenched casting to 580-620℃, hold for 4-8 hours, and then air cool to room temperature.

[0018] Preferably, the water toughening treatment specifically includes: heating to 300℃ at 30-40℃ / h and holding for 1 hour; heating to 510℃ at 45℃ / h and holding for 2 hours; heating to 720℃ at 30℃ / h and holding for 1.5 hours; heating to 1080-1120℃ at 35℃ / h and holding for t; and then quickly immersing it in room temperature cooling water, ensuring that the cooling water temperature does not exceed 45℃ during the cooling process;

[0019] The holding time t satisfies: t = 0.018 × a × [1.3 × (C + Si + 0.5Cr + Mo)],

[0020] Where t is the heat preservation time in hours; a is the maximum wall thickness of the liner in mm; and C, Si, Cr, and Mo are the mass fractions of C, Si, Cr, and Mo elements in the steel.

[0021] The beneficial effects of this invention are as follows:

[0022] This invention uses only Cr, Mo, V, and Ti elements for alloying. By optimizing the mass ratio of Mn / C, the mass ratio of Cr / V, and the total mass percentage of Cr+Mo, the composition and proportion of the elements are optimized, allowing each component in the high-manganese steel to fully exert its synergistic effect, improving the hardness and strength of the steel, and reducing the need for large amounts of Ni, Mo, and other elements, thus significantly reducing costs.

[0023] The preparation process adopts a three-step heat treatment process. The first heat treatment eliminates the internal stress during the processing of the liner steel, reduces the possibility of deformation and cracking, and also makes the steel microstructure distribution more uniform, improves the consistency of the microstructure, and prepares the microstructure for subsequent water quenching treatment.

[0024] The holding time for water quenching is dynamically adjusted according to the thickness of the liner plate, taking into account the influence of C, Si, Cr, and Mo elements in the steel. Appropriate coefficients are adjusted to cover the dissolution energy barrier, ensuring complete dissolution of carbides and saving energy during water quenching. The water quenching heating employs a four-stage heating process, optimizing the heating rate and temperature gradient for each stage based on the influence of the liner plate's composition on its thermal conductivity. This eliminates the risk of thermal stress cracking. Furthermore, the staged heating provides the necessary conditions for the complete dissolution of carbides, further ensuring the hardness and strength properties of the steel.

[0025] The second heat treatment promotes the re-dispersion and precipitation of nano-carbides in the steel, which are then dispersed in the austenitic matrix as precipitates. The grain size of the steel is controlled at grade 8-10, and the size of the precipitated carbides is less than 80 nm. The prepared steel for ultra-wear-resistant cone liners for crushers can achieve a hardness of 289 HB and an impact toughness of 203 J / cm. 2 The tensile strength can reach 849 MPa. This steel, used for ultra-wear-resistant cone liners in crushers, has high hardness, high tensile strength, and excellent impact toughness. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the manufacturing process of steel for ultra-wear-resistant cone liners for crushers, as disclosed in an embodiment of the present invention. Detailed Implementation

[0028] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] With the increasing size of mining equipment, the service conditions of liner plates are becoming more stringent, and existing liner steels are insufficient to meet the requirements of low cost and high performance. There is an urgent need to develop a low-cost, high-strength, and high-hardness liner steel to extend the service life of liners, meet market demands, and drive industry development.

[0030] To address the aforementioned technical problems, embodiments of the present invention provide a steel for ultra-wear-resistant cone liners of crushers, comprising the following components by mass percentage: C: 1.30-1.50%, Mn: 22-25%, Si: 0.35-0.80%, Cr: 2.0-2.5%, V: 0.1-0.15%, Ti: 0.06-0.12%, N: 0.05-0.08%, Mo: 0.3-0.6%, P≤0.035%, S≤0.015%, with the balance being Fe and unavoidable impurities.

[0031] In one embodiment, the Mn / C mass ratio is 16-18, the Cr / V mass ratio is 16-20, and the total mass percentage of Cr+Mo is ≤2.8%.

[0032] Carbon (C) is an important solid solution strengthening element in high-manganese steel, enabling it to possess both high hardness and toughness. Excessive C content can cause excessive lattice distortion or the precipitation of large carbides at grain boundaries, reducing the steel's plasticity. The optimal C content is 1.30-1.50%.

[0033] Manganese (Mn) is the main component of austenitic manganese alloy steel. Mn expands the austenite phase region and stabilizes the austenitic microstructure. Part of Mn dissolves in austenite, increasing the stability of supercooled austenite and improving its hardenability; another part exists in carbides such as (Fe,Mn)3C and Mn7C, improving the strength and impact toughness of high-manganese steel. When the carbon (C) content in steel is constant, as the Mn content increases, the microstructure gradually transforms from pearlitic to martensitic and then further to austenitic, promoting the formation of a single austenitic microstructure at room temperature. Furthermore, Mn can influence the deformation mechanism of steel by affecting stacking fault energy; as the Mn content increases, the deformation mechanism of austenitic steel gradually changes from the TRIP effect to the TWIP effect. Therefore, the Mn content is controlled between 22-25%.

[0034] Si is the main element for improving the structure and morphology of carbides. When the Si content is high, it helps the eutectic carbides to have a highly MC-type structure, which helps improve the morphology of carbides and improve the strength and wear resistance of high manganese steel. The Si content should be controlled within the range of 0.35-0.80%.

[0035] Cr is a stabilizing element, which helps improve the stability of room temperature austenite. Cr can combine with C to form various types of carbides such as (Fe,Cr)3C. These carbides exist as dispersed hard particles in the matrix of high-manganese steel, increasing the initial hardness of high-manganese steel. Therefore, the Cr content is controlled between 2.0% and 2.5%.

[0036] The main function of molybdenum (Mo) is to increase the hardenability of high-manganese steel, refine the microstructure, and improve the strength and toughness of the matrix. The Mo content is controlled within the range of 0.3-0.6%.

[0037] Nitrogen (N) can form nitrides in high-manganese steel, such as TiN and VN, which are wear-resistant hard particles. The effect is better when the content is in the range of 0.05-0.08%.

[0038] V has the effect of improving hardenability, forming stable carbides, and refining grains. In particular, when combined with titanium, it can improve work hardening performance and wear resistance. The effect is better when the V content is controlled at 0.1-0.15%.

[0039] Ti is a strong carbide-forming element that refines grains, eliminates columnar crystals, forms hard particles (TiC, TiN), and improves wear resistance. Adding 0.06-0.12% titanium can significantly improve wear resistance.

[0040] The components in high-manganese steel have synergistic effects. Controlling the Mn / C mass ratio to 16-18 ensures high work hardening capacity while preventing excessive carbides and improving toughness. Controlling the Cr / V mass ratio to 16-20 controls the size and quantity of carbides such as Fe, Cr, 3C, and VC in the steel, ensuring grain refinement and guaranteeing the dispersion of precipitated phases. Controlling the total mass percentage of Cr+Mo to ≤2.8% better balances the hardness and toughness of the steel, ensuring wear resistance while preventing degradation of impact toughness.

[0041] In one embodiment, the steel for the ultra-wear-resistant cone liner of the crusher contains the following components by mass percentage: C: 1.4%, Mn: 23%, Si: 0.4%, Cr: 2.3%, V: 0.13%, Ti: 0.1%, N: 0.06%, Mo: 0.4%, P≤0.035%, S≤0.015%, with the balance being Fe and unavoidable impurities.

[0042] like Figure 1 As shown, an embodiment of the present invention provides a method for preparing steel for ultra-wear-resistant cone liners for crushers, comprising the following steps:

[0043] Smelting: The ingredients are prepared according to the chemical composition, and smelting is carried out in an electric arc furnace or a medium-frequency induction furnace. The temperature is controlled at 1600-1650℃ during the smelting process, and deoxidation and desulfurization treatment are carried out.

[0044] Casting: The molten steel is poured into the casting to obtain the casting. The casting temperature is controlled at 1450-1550℃.

[0045] First heat treatment: Heat the casting to 850-880℃ and hold for 2-3 hours, then air cool for the first heat treatment;

[0046] Water quenching: The casting is heated to 1080-1120℃ at a rate of 40-50℃ / h and held at that temperature for a duration t that satisfies: t = 0.018 × a × [1.3 × (C + Si + 0.5Cr + Mo)].

[0047] Where t is the heat preservation time in hours; a is the maximum wall thickness of the liner in mm; and C, Si, Cr, and Mo are the mass fractions of C, Si, Cr, and Mo elements in the steel.

[0048] After heat preservation, water quenching and cooling are performed at a rate ≥50℃ / s; the maximum wall thickness of the liner plate is 40-80mm.

[0049] Second heat treatment: Heat the water-quenched casting to 580-620℃, hold for 4-8 hours, and then air cool to room temperature.

[0050] The present invention does not impose any special restrictions on the smelting and casting methods of the steel used for the ultra-wear-resistant cone liner of the crusher. The casting can be a method well known to those skilled in the art, such as sand casting or metal casting.

[0051] The first heat treatment is set at 850-880℃ and held for 2-3 hours, followed by air cooling. This can eliminate the internal stress during the processing of the lining steel, reduce the possibility of deformation and cracking, and make the steel's microstructure distribution more uniform, improving the consistency of the microstructure and preparing the microstructure for subsequent water quenching treatment.

[0052] Water quenching is performed at 1080-1120℃. Temperatures that are too low are detrimental to carbide dissolution, while temperatures that are too high can lead to overheating. The holding time (t) is dynamically adjusted according to the liner thickness, taking into account the effects of C, Si, Cr, and Mo elements in the steel. Appropriate coefficients are adjusted to cover the dissolution energy barrier, ensuring complete carbide dissolution and saving energy during water quenching. A water quenching cooling rate ≥50℃ / s ensures the formation of a single austenite structure and avoids pearlite transformation.

[0053] The second heat treatment reheats the steel to 580-620℃ and holds it for 4-8 hours, which promotes the re-dispersion and precipitation of nano-carbides in the steel. These carbides are dispersed in the austenitic matrix as precipitates, and their size is less than 80nm, which further improves the hardness of the liner steel.

[0054] In one embodiment, the water toughening treatment specifically includes: heating to 300°C at a rate of 30-40°C / h and holding for 1 hour; heating to 510°C at a rate of 45°C / h and holding for 2 hours; heating to 720°C at a rate of 30°C / h and holding for 1.5 hours; heating to 1080-1120°C at a rate of 35°C / h and holding for t; and then rapidly immersing the water in room temperature cooling water, ensuring that the cooling water temperature does not exceed 45°C during the cooling process.

[0055] The holding time t satisfies: t = 0.018 × a × [1.3 × (C + Si + 0.5Cr + Mo)],

[0056] Where t is the heat preservation time in hours; a is the maximum wall thickness of the liner in mm; and C, Si, Cr, and Mo are the mass fractions of C, Si, Cr, and Mo elements in the steel.

[0057] Because high-manganese steel has a very low thermal conductivity and a large coefficient of thermal expansion, it is prone to thermal stress during heating. Combined with the casting stress inherent in the casting itself, this makes high-manganese steel castings extremely susceptible to cracking during heat treatment, especially for large parts with complex structures and significant differences in wall thickness. This application preferably employs a four-stage heating method and, based on the influence of the composition of the liner on the thermal conductivity of the liner according to the present invention, optimizes the heating rate and temperature gradient of each stage to eliminate the risk of thermal stress cracking. Furthermore, the staged heating also provides the basic conditions for the complete dissolution of carbides, further ensuring the hardness and strength properties of the steel.

[0058] After the above heat treatment, the alloying elements in the steel for the ultra-wear-resistant cone liner of the crusher can be fully utilized, the grain size of the steel is controlled at level 8-10, and the size of the precipitated carbides in the steel is less than 80nm. The prepared steel for the ultra-wear-resistant cone liner of the crusher can achieve a hardness of 289HB and an impact toughness of 203J / cm. 2 The tensile strength can reach 849MPa. This steel, used for ultra-wear-resistant cone liners in crushers, exhibits high hardness, high tensile strength, and excellent impact toughness. It is alloyed using only Cr, Mo, V, and Ti elements, and by optimizing the proportions and ratios of these elements, the synergistic effect of each element is fully utilized, significantly reducing the need for large amounts of Ni, Mo, and other elements, thus greatly lowering costs.

[0059] Example 1: A method for preparing steel for ultra-wear-resistant cone liners of crushers, comprising the following steps:

[0060] Smelting: Prepare the raw materials according to the chemical composition in Table 1, and smelt them using an electric arc furnace or a medium-frequency induction furnace. During the smelting process, control the temperature at 1610℃ and carry out deoxidation and desulfurization treatment.

[0061] Casting: The molten steel is poured into the casting to obtain the casting. The casting temperature is controlled at 1451℃.

[0062] First heat treatment: The casting is heated to 850℃ and held for 3 hours, then air cooled for the first heat treatment.

[0063] Water quenching: The casting is heated to 1080℃ at a rate of 40℃ / h and held at that temperature for a duration t that satisfies: t = 0.018 × a × [1.3 × (C + Si + 0.5Cr + Mo)].

[0064] Where t is the heat preservation time in hours (h); a is the maximum wall thickness of the liner in millimeters (mm); C, Si, Cr, and Mo are the mass fractions of C, Si, Cr, and Mo elements in the steel; and the maximum wall thickness of the liner is 40 mm.

[0065] After heat preservation, water quenching and cooling are performed at a rate of 55℃ / s.

[0066] Second heat treatment: Heat the water-quenched casting to 590℃, hold for 6 hours, and then air cool to room temperature.

[0067] Example 2: A method for preparing steel for ultra-wear-resistant cone liners of crushers, comprising the following steps:

[0068] Smelting: Prepare the raw materials according to the chemical composition in Table 1, and smelt them using an electric arc furnace or a medium-frequency induction furnace. During the smelting process, control the temperature at 1620℃ and carry out deoxidation and desulfurization treatment.

[0069] Casting: The molten steel is poured into the casting to obtain the casting. The casting temperature is controlled at 1500℃.

[0070] First heat treatment: The casting is heated to 860℃ and held at that temperature for 2.5 hours, then air-cooled for the first heat treatment.

[0071] Water quenching: The casting is heated to 1100℃ at a rate of 45℃ / h and held at that temperature for a duration t that satisfies: t = 0.018 × a × [1.3 × (C + Si + 0.5Cr + Mo)].

[0072] Where t is the heat preservation time in hours (h); a is the maximum wall thickness of the liner in millimeters (mm); C, Si, Cr, and Mo are the mass fractions of C, Si, Cr, and Mo elements in the steel; and the maximum wall thickness of the liner is 50 mm.

[0073] After heat preservation, water quenching and cooling are performed at a rate of 56℃ / s.

[0074] Second heat treatment: Heat the water-quenched casting to 600℃, hold for 5 hours, and then air cool to room temperature.

[0075] Example 3: A method for preparing steel for ultra-wear-resistant cone liners of crushers, comprising the following steps:

[0076] Smelting: Prepare the raw materials according to the chemical composition in Table 1, and smelt them using an electric arc furnace or a medium-frequency induction furnace. During the smelting process, control the temperature at 1650℃ and carry out deoxidation and desulfurization treatment.

[0077] Casting: The molten steel is poured into the casting to obtain the casting. The casting temperature is controlled at 1450℃.

[0078] First heat treatment: The casting is heated to 880℃ and held for 2 hours, then air-cooled for the first heat treatment.

[0079] Water quenching: The casting is heated to 1120℃ at a rate of 45℃ / h and held at that temperature for a duration t that satisfies: t = 0.018 × a × [1.3 × (C + Si + 0.5Cr + Mo)].

[0080] Where t is the heat preservation time in hours (h); a is the maximum wall thickness of the liner in millimeters (mm); C, Si, Cr, and Mo are the mass fractions of C, Si, Cr, and Mo elements in the steel; and the maximum wall thickness of the liner is 60 mm.

[0081] After heat preservation, water quenching and cooling are performed at a rate of 70℃ / s.

[0082] Second heat treatment: Heat the water-cooled casting to 580℃, hold for 4 hours, and then air cool to room temperature.

[0083] Example 4: A method for preparing steel for ultra-wear-resistant cone liners of crushers, comprising the following steps:

[0084] Smelting: Prepare the raw materials according to the chemical composition in Table 1, and smelt them using an electric arc furnace or a medium-frequency induction furnace. During the smelting process, control the temperature at 1640℃ and carry out deoxidation and desulfurization treatment.

[0085] Casting: The molten steel is poured into the casting to obtain the casting. The casting temperature is controlled at 1550℃.

[0086] First heat treatment: The casting is heated to 870℃ and held at that temperature for 2.6 hours, then air-cooled for the first heat treatment.

[0087] Water quenching: The casting is heated to 1090℃ at a rate of 50℃ / h and held at that temperature for a duration t that satisfies: t = 0.018 × a × [1.3 × (C + Si + 0.5Cr + Mo)].

[0088] Where t is the heat preservation time in hours (h); a is the maximum wall thickness of the liner in millimeters (mm); C, Si, Cr, and Mo are the mass fractions of C, Si, Cr, and Mo elements in the steel; and the maximum wall thickness of the liner is 80 mm.

[0089] After heat preservation, water quenching and cooling are performed at a rate of 70℃ / s.

[0090] Second heat treatment: Heat the water-cooled casting to 620℃, hold for 8 hours, and then air cool to room temperature.

[0091] Comparative Examples 1-2:

[0092] The composition of the steel used for the ultra-wear-resistant cone liner of the crusher in Comparative Examples 1-2 is shown in Table 1, and the specific preparation process parameters are the same as those in Example 2.

[0093] The composition of the steel used for the ultra-wear-resistant cone liners of crushers in Examples 1-4 and Comparative Examples 1-2 is shown in Table 1.

[0094] Table 1. Composition of steels in Examples 1-4 and Comparative Examples 1-2

[0095] C Mn Si Cr V Ti N Mo P S Mn / C Cr / V Cr+Mo Example 1 1.3 22 0.35 2.0 0.12 0.07 0.07 0.3 0.02 0.007 16.9 16.7 2.3 Example 2 1.4 23 0.4 2.3 0.13 0.1 0.06 0.4 0.02 0.006 16.4 17.7 2.7 Example 3 1.5 25 0.8 2.5 0.1 0.06 0.08 0.6 0.01 0.005 16.7 25 3.1 Example 4 1.5 22 0.5 2.1 0.15 0.12 0.05 0.5 0.01 0.006 14.7 14 2.6 Comparative Example 1 1.1 20 0.2 1.6 0.2 0.1 0.06 0.5 0.01 0.006 18.2 8 2.1 Comparative Example 2 1.6 28 0.6 3.0 0.08 0.05 0.06 0.2 0.03 0.01 17.5 37.5 3.2

[0096] Example 5: The preparation method of the ultra-wear-resistant cone liner steel for crushers in Example 5 differs from that in Example 2 only in the water toughening process:

[0097] The water-toughening treatment specifically includes: heating to 300℃ at 30℃ / h and holding for 1 hour; heating to 510℃ at 45℃ / h and holding for 2 hours; heating to 720℃ at 30℃ / h and holding for 1.5 hours; heating to 1100℃ at 35℃ / h and holding for t; then quickly immersing in room temperature cooling water, ensuring that the cooling water temperature does not exceed 45℃ during the cooling process;

[0098] The holding time t satisfies: t = 0.018 × a × [1.3 × (C + Si + 0.5Cr + Mo)],

[0099] Where t is the heat preservation time in hours; a is the maximum wall thickness of the liner in mm; C, Si, Cr, and Mo are the mass fractions of C, Si, Cr, and Mo elements in the steel, and the maximum wall thickness of the liner is 50 mm.

[0100] Example 6: The method for preparing the ultra-wear-resistant cone liner steel for crushers in Example 6 differs from that in Example 1 only in the water toughening process:

[0101] The water-toughening treatment specifically includes: heating to 300℃ at 40℃ / h and holding for 1 hour; heating to 510℃ at 45℃ / h and holding for 2 hours; heating to 720℃ at 30℃ / h and holding for 1.5 hours; heating to 1080℃ at 35℃ / h and holding for t; then quickly immersing in room temperature cooling water, ensuring that the cooling water temperature does not exceed 45℃ during the cooling process;

[0102] The holding time t satisfies: t = 0.018 × a × [1.3 × (C + Si + 0.5Cr + Mo)],

[0103] Where t is the heat preservation time in hours; a is the maximum wall thickness of the liner in mm; C, Si, Cr, and Mo are the mass fractions of C, Si, Cr, and Mo elements in the steel, and the maximum wall thickness of the liner is 40 mm.

[0104] The steel used for the ultra-wear-resistant cone liners for crushers prepared in Examples 1-5 and Comparative Examples 1-2 was subjected to performance tests, and the results are shown in Table 1.

[0105] Table 2: Performance data of steels prepared in Examples 1-5 and Comparative Examples 1-2

[0106] Hardness (HB) Tensile strength (MPa) <![CDATA[Impact toughness (J / cm 2 )]]> Example 1 270 810 185 Example 2 281 830 192 Example 3 263 795 180 Example 4 260 787 177 Example 5 289 842 193 Example 6 286 849 203 Comparative Example 1 251 760 166 Comparative Example 2 242 743 163

[0107] As shown in Table 2, the steel used for the ultra-wear-resistant cone liner of the crusher prepared by this invention can reach a hardness of 289HB and an impact toughness of 203J / cm. 2 The tensile strength can reach 849MPa. This steel, used for ultra-wear-resistant cone liners in crushers, exhibits high hardness, high tensile strength, and excellent impact toughness. It is alloyed using only Cr, Mo, V, and Ti elements, and by optimizing the proportions and ratios of these elements, the synergistic effect of each element is fully utilized, significantly reducing the need for large amounts of Ni, Mo, and other elements, thus greatly lowering costs.

[0108] Examples 1-2 control the composition of Mn / C mass ratio to be 16-18, Cr / V mass ratio to be 16-20, and the total mass percentage of Cr+Mo to be ≤2.8%, which can better exert the synergistic effect of alloying elements and have better hardness, tensile strength and impact toughness compared to Examples 3-4.

[0109] Examples 5-6 further optimized the water toughening process, and the staged heating also provided the basic conditions for the full dissolution of carbides, further ensuring the hardness and strength properties of the steel, with better performance than Examples 1-4.

[0110] Comparative Examples 1-2 changed the alloy composition, and the role of each component could not be fully utilized, resulting in a decrease in the hardness, tensile strength and impact toughness of the steel.

[0111] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A type of steel for ultra-wear-resistant cone liners in crushers, characterized in that, It contains the following components by mass percentage: C: 1.30-1.50%, Mn: 23-25%, Si: 0.35-0.80%, Cr: 2.0-2.5%, V: 0.1-0.15%, Ti: 0.06-0.12%, N: 0.05-0.08%, Mo: 0.3-0.5%, P≤0.035%, S≤0.015%, with the balance being Fe and unavoidable impurities; The mass ratio of Mn / C is 16-18, the mass ratio of Cr / V is 16-20, and the total mass percentage of Cr+Mo is ≤2.8%. The method for preparing the steel for the ultra-wear-resistant cone liner of the crusher includes the following steps: Smelting: The raw materials are batched according to the chemical composition and smelted using an electric arc furnace or a medium-frequency induction furnace. The temperature is controlled at 1600-1650℃ during the smelting process, and deoxidation and desulfurization treatments are carried out. Casting: The molten steel is poured into the casting to obtain the casting. The casting temperature is controlled at 1450-1550℃. First heat treatment: Heat the casting to 850-880℃ and hold for 2-3 hours, then air cool for the first heat treatment; Water toughening treatment: Specifically, it includes: first, heating to 300℃ at 30-40℃ / h and holding for 1 hour; then heating to 510℃ at 45℃ / h and holding for 2 hours; then heating to 720℃ at 30℃ / h and holding for 1.5 hours; finally, heating to 1080-1120℃ at 35℃ / h and holding for t; then quickly immersing in room temperature cooling water, ensuring that the cooling water temperature does not exceed 45℃ during the cooling process, and the cooling rate is ≥50℃ / s; The heat preservation time t = 0.018 × a × [1.3 × (C + Si + 0.5Cr + Mo)], Where t is the heat preservation time in hours; a is the maximum wall thickness of the liner in mm; and C, Si, Cr, and Mo are the mass fractions of C, Si, Cr, and Mo elements in the steel. Second heat treatment: Heat the water-quenched casting to 580-620℃, hold for 4-8 hours, and then air cool to room temperature.

2. The steel for ultra-wear-resistant cone liners of crushers according to claim 1, characterized in that, It contains the following components by mass percentage: C: 1.4%, Mn: 23%, Si: 0.4%, Cr: 2.3%, V: 0.13%, Ti: 0.1%, N: 0.06%, Mo: 0.4%, P≤0.035%, S≤0.015%, balance Fe and unavoidable impurities.

3. The steel for ultra-wear-resistant cone liners for crushers according to any one of claims 1-2, characterized in that, The grain size of the steel is grade 8 to 10, and the size of the precipitated carbides in the steel is less than 80 nm.

4. A method for preparing steel for ultra-wear-resistant cone liners for crushers according to any one of claims 1-3, characterized in that: Includes the following steps: Smelting: The raw materials are batched according to the chemical composition and smelted using an electric arc furnace or a medium-frequency induction furnace. The temperature is controlled at 1600-1650℃ during the smelting process, and deoxidation and desulfurization treatments are carried out. Casting: The molten steel is poured into the casting to obtain the casting. The casting temperature is controlled at 1450-1550℃. First heat treatment: Heat the casting to 850-880℃ and hold for 2-3 hours, then air cool for the first heat treatment; Water toughening treatment: Specifically, it includes: first, heating to 300℃ at 30-40℃ / h and holding for 1 hour; then heating to 510℃ at 45℃ / h and holding for 2 hours; then heating to 720℃ at 30℃ / h and holding for 1.5 hours; finally, heating to 1080-1120℃ at 35℃ / h and holding for t; then quickly immersing in room temperature cooling water, ensuring that the cooling water temperature does not exceed 45℃ during the cooling process, and the cooling rate is ≥50℃ / s; The heat preservation time t = 0.018 × a × [1.3 × (C + Si + 0.5Cr + Mo)], Where t is the heat preservation time in hours; a is the maximum wall thickness of the liner in mm; and C, Si, Cr, and Mo are the mass fractions of C, Si, Cr, and Mo elements in the steel. Second heat treatment: Heat the water-quenched casting to 580-620℃, hold for 4-8 hours, and then air cool to room temperature.

5. The method for preparing steel for ultra-wear-resistant cone liners of crushers according to claim 4, characterized in that, The maximum wall thickness 'a' of the liner plate ranges from 40 to 80 mm.

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