High plasticity wear-resistant steel plate and smelting process thereof

Abstract

The application relates to the technical field of steel smelting, and discloses a high-plasticity high-toughness wear-resistant steel plate and a smelting process thereof, which is composed of the following components in percentage by weight: C 0.18%-0.25%, Si 0.2%-0.6%, Mn 1.0%-1.5%, Nb 0.02%-0.05%, Ti 0.005%-0.03%, Cr 0.5%-1.0%, Mo 0.3%-0.6%, V 0.03%-0.1%, and the balance of Fe and inevitable impurities; the ratio of Si+Nb to V+Ti is 2<= (Si+Nb) / (V+Ti) <=15. Through the technical scheme, the problem of poor wear resistance of the steel plate in the related art is solved.

Description

Technical Field

[0001] This invention relates to the field of iron and steel smelting technology, specifically to a high-ductility, high-toughness wear-resistant steel plate and its smelting process. Background Technology

[0002] In modern industrial systems, wear-resistant steel plates serve as a crucial basic material, playing an irreplaceable role in numerous fields. From excavator buckets and bulldozer blades in the construction machinery sector, to crusher liners and scraper conveyors in mining machinery, and coal mill liners in the power industry, their applications are extremely wide-ranging. With continuous industrial development, the performance requirements for wear-resistant steel plates are becoming increasingly stringent. Not only are excellent wear resistance expected to extend equipment lifespan and reduce maintenance costs, but higher standards are also being set for their ductility and toughness to meet the forming and processing requirements and impact resistance needs under complex working conditions.

[0003] Currently, traditional wear-resistant steel plates have certain limitations in terms of production processes and performance. Improving wear resistance is often achieved by increasing carbon content or adding large amounts of alloying elements. However, increasing carbon content significantly reduces the ductility and toughness of the steel plate, making it prone to brittle fracture under stress. Therefore, developing a high-ductility and high-toughness wear-resistant steel plate is of great significance. Summary of the Invention

[0004] This invention proposes a high-ductility and wear-resistant steel plate and its smelting process, which solves the problem of poor wear resistance of steel plates in related technologies.

[0005] The technical solution of the present invention is as follows:

[0006] This invention proposes a high-ductility and wear-resistant steel plate, which, by weight percentage, is composed of the following components: C 0.18%~0.25%, Si 0.2%~0.6%, Mn 1.0%~1.5%, Nb 0.02%~0.05%, Ti 0.005%~0.03%, Cr 0.5%~1.0%, Mo 0.3%~0.6%, V 0.03%~0.1%, with the balance being Fe and unavoidable impurities; the ratio of Si+Nb to V+Ti is: 2≤(Si+Nb) / (V+Ti)≤15.

[0007] As a further technical solution, the weight ratio of V to Ti is 6~9:1.

[0008] In this invention, Ti, V, and C form carbides in the steel plate. The Ti carbides preferentially precipitate in the molten steel, while the V carbides grow on the basis of the Ti carbides, forming composite carbide particles. By controlling the weight ratio of V to Ti to be 6~9:1, the carbide particle size can be more uniformly distributed, forming a dense and dispersed strengthening phase in the steel matrix, thereby improving the wear resistance of the steel plate. The carbides formed by Ti and V can effectively inhibit grain boundary migration and grain growth, and the refined grains can reduce the surface plastic deformation of the steel plate and improve wear resistance.

[0009] This invention also proposes a smelting process for high-ductility and high-toughness wear-resistant steel plates, used to prepare the aforementioned high-ductility and high-toughness wear-resistant steel plates, comprising the following steps:

[0010] S1. After the ingredients are prepared according to the description, steel ingots are obtained through smelting and casting.

[0011] S2. The steel ingot is heated, rolled, and heat-treated to obtain a high-ductility and wear-resistant steel plate.

[0012] As a further technical solution, in step S2, a CH4-CO2-N2 mixed gas is introduced during heating.

[0013] In this invention, a CH4-CO2-N2 mixed gas is introduced into the high-temperature heating environment. The gas reacts with the molten steel to generate active atoms, which dissolve in the molten steel. After dissolving into the ferrite lattice, the atoms exist in the form of interstitial solid solution, causing lattice distortion. When dislocations move in the lattice, the stress field generated by the lattice distortion hinders the movement of dislocations and increases the strength of the steel plate.

[0014] As a further technical solution, the volume ratio of CH4, CO2, and N2 in the CH4-CO2-N2 mixed gas is 2:1:3~8.

[0015] In this invention, by limiting the volume ratio of CH4, CO2, and N2 in the CH4-CO2-N2 mixed gas to 2:1:3~8, the amount of carbon and nitrogen dissolved can be precisely controlled, thereby further improving the strength of the steel plate.

[0016] As a further technical solution, the heating temperature is 1150~1200℃, and the heating time is 1~2h.

[0017] As a further technical solution, the heat treatment includes normalizing, quenching, and tempering.

[0018] As a further technical solution, the normalizing temperature is 880~900℃ and the normalizing time is 50~60min; the quenching temperature is 870~900℃ and the quenching time is 50~60min; the tempering temperature is 450~500℃ and the tempering time is 1~2h.

[0019] As a further technical solution, the quenching cooling rate is 50~60℃ / s.

[0020] As a further technical solution, the initial rolling temperature is 1080~1120℃, and the final rolling temperature is 810~830℃.

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

[0022] In this invention, by adding Si, Nb, Ti and V elements to steel and limiting 3≤(Si+Nb) / (V+Ti)≤15, grain growth can be hindered during the solidification and cooling process of steel, thereby refining the grains, improving the strength and hardness of the steel, and forming carbide particles with carbon that are distributed in the steel matrix, enhancing the precipitation strengthening effect of the steel and improving the wear resistance of the steel plate. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0024] In the following embodiments and comparative examples:

[0025] Ferrosilicon alloy, silicon content 75wt%; ferromanganese alloy, manganese content 68wt%; ferrochrome alloy, chromium content 60wt%; ferrotitanium alloy, titanium content 80wt%; ferromolybdenum alloy, molybdenum content 70wt%; ferrovanadium alloy, vanadium content 50wt%; ferroniobium alloy, niobium content 40wt%.

[0026] Example 1

[0027] The high-ductility and toughness wear-resistant steel plate, by weight percentage, consists of the following components: C 0.18%, Si 0.2%, Mn 1.0%, Nb 0.02%, Ti 0.01%, Cr 0.5%, Mo 0.3%, V 0.1%, with the balance being Fe and unavoidable impurities;

[0028] A smelting process for high-ductility and high-toughness wear-resistant steel plates includes the following steps:

[0029] S1. Iron blocks, carbon powder, ferrosilicon alloy, ferromanganese alloy, ferrochrome alloy, ferrotitanium alloy, ferroniobium alloy, ferrochrome alloy, ferromolybdenum alloy, and ferrovanadium alloy are mixed according to their components and then smelted and cast to obtain steel ingots.

[0030] S2. Heat the steel ingot to 1150℃ in a CO2 atmosphere and hold for 2 hours. Roll it at 1080℃ with a final rolling temperature of 810℃. Then, normalize it at 880℃ for 60 minutes, quench it at 870℃, hold it for 60 minutes, and cool it to room temperature at a rate of 50℃ / s. Finally, temper it at 450℃ for 2 hours to obtain a high-ductility and wear-resistant steel plate.

[0031] Example 2

[0032] The high-ductility and wear-resistant steel plate is composed of the following components by weight percentage: C 0.22%, Si 0.4%, Mn 1.2%, Nb 0.05%, Ti 0.02%, Cr 0.7%, Mo 0.5%, V 0.05%, with the balance being Fe and unavoidable impurities;

[0033] A smelting process for high-ductility and high-toughness wear-resistant steel plates includes the following steps:

[0034] S1. Iron blocks, carbon powder, ferrosilicon alloy, ferromanganese alloy, ferrochrome alloy, ferrotitanium alloy, ferroniobium alloy, ferrochrome alloy, ferromolybdenum alloy, and ferrovanadium alloy are mixed according to their components and then smelted and cast to obtain steel ingots.

[0035] S2. Heat the steel ingot to 1170℃ in a CO2 atmosphere and hold for 2 hours. Roll it at 1100℃ with a final rolling temperature of 820℃. Then, normalize it at 890℃ for 60 minutes, quench it at 890℃, hold it for 60 minutes, and cool it to room temperature at a rate of 55℃ / s. Finally, temper it at 470℃ for 2 hours to obtain a high-ductility and wear-resistant steel plate.

[0036] Example 3

[0037] The high-ductility and wear-resistant steel plate is composed of the following components by weight percentage: C 0.25%, Si 0.6%, Mn 1.5%, Nb 0.03%, Ti 0.005%, Cr 1.0%, Mo 0.6%, V 0.037%, with the balance being Fe and unavoidable impurities;

[0038] A smelting process for high-ductility and high-toughness wear-resistant steel plates includes the following steps:

[0039] S1. Iron blocks, carbon powder, ferrosilicon alloy, ferromanganese alloy, ferrochrome alloy, ferrotitanium alloy, ferroniobium alloy, ferrochrome alloy, ferromolybdenum alloy, and ferrovanadium alloy are mixed according to their components and then smelted and cast to obtain steel ingots.

[0040] S2. Heat the steel ingot to 1200℃ in a CO2 atmosphere and hold for 1 hour. Roll it at 1120℃ with a final rolling temperature of 830℃. Then, normalize it at 900℃ for 50 minutes, quench it at 900℃, hold it for 50 minutes, and cool it to room temperature at a rate of 60℃ / s. Finally, temper it at 500℃ for 1 hour to obtain a high-ductility and wear-resistant steel plate.

[0041] Example 4

[0042] The only difference between this embodiment and Embodiment 2 is that the high-ductility and wear-resistant steel plate, by weight percentage, is composed of the following components: C 0.22%, Si 0.2%, Mn 1.2%, Nb 0.02%, Ti 0.02%, Cr 0.7%, Mo 0.5%, V 0.05%, with the balance being Fe and unavoidable impurities.

[0043] Example 5

[0044] The only difference between this embodiment and Embodiment 2 is that the high-ductility and wear-resistant steel plate, by weight percentage, is composed of the following components: C 0.22%, Si 0.6%, Mn 1.2%, Nb 0.05%, Ti 0.02%, Cr 0.7%, Mo 0.5%, V 0.05%, with the balance being Fe and unavoidable impurities.

[0045] Example 6

[0046] The only difference between this embodiment and Embodiment 2 is that the high-ductility and wear-resistant steel plate, by weight percentage, is composed of the following components: C 0.22%, Si 0.4%, Mn 1.2%, Nb 0.04%, Ti 0.005%, Cr 0.7%, Mo 0.5%, V 0.065%, with the balance being Fe and unavoidable impurities.

[0047] Example 7

[0048] The only difference between this embodiment and Embodiment 2 is that the high-ductility and wear-resistant steel plate, by weight percentage, is composed of the following components: C 0.22%, Si 0.4%, Mn 1.2%, Nb 0.04%, Ti 0.01%, Cr 0.7%, Mo 0.5%, V 0.06%, with the balance being Fe and unavoidable impurities.

[0049] Example 8

[0050] The only difference between this embodiment and Embodiment 2 is that the high-ductility and wear-resistant steel plate, by weight percentage, is composed of the following components: C 0.22%, Si 0.4%, Mn 1.2%, Nb 0.04%, Ti 0.007%, Cr 0.7%, Mo 0.5%, V 0.063%, with the balance being Fe and unavoidable impurities.

[0051] Example 9

[0052] The only difference between this embodiment and embodiment 8 is that the heating atmosphere is a CH4-CO2 mixture with a volume ratio of 2:1.

[0053] Example 10

[0054] The only difference between this embodiment and embodiment 8 is that the heating atmosphere is a CH4-CO2-N2 mixed gas with a volume ratio of 2:1:1.

[0055] Example 11

[0056] The only difference between this embodiment and Embodiment 10 is that the volume ratio of CH4-CO2-N2 is 2:1:10.

[0057] Example 12

[0058] The only difference between this embodiment and Embodiment 10 is that the volume ratio of CH4-CO2-N2 is 2:1:3.

[0059] Example 13

[0060] The only difference between this embodiment and Embodiment 10 is that the volume ratio of CH4-CO2-N2 is 2:1:8.

[0061] Comparative Example 1

[0062] The only difference between this comparative example and Example 1 is that the high-ductility and wear-resistant steel plate, by weight percentage, consists of the following components: C 0.18%, Si 0.2%, Mn 1.0%, Nb 0.02%, Ti 0.03%, Cr 0.5%, Mo 0.3%, V 0.1%, with the balance being Fe and unavoidable impurities.

[0063] Comparative Example 2

[0064] The only difference between this comparative example and Example 1 is that the high-ductility and toughness wear-resistant steel plate, by weight percentage, consists of the following components: C 0.18%, Si 0.2%, Mn 1.0%, Nb 0.02%, Ti 0.04%, Cr 0.5%, Mo 0.3%, with the balance being Fe and unavoidable impurities.

[0065] Comparative Example 3

[0066] The only difference between this comparative example and Example 1 is that the high-ductility and wear-resistant steel plate, by weight percentage, consists of the following components: C 0.18%, Si 0.2%, Mn 1.0%, Nb 0.02%, Cr 0.5%, Mo 0.3%, V 0.04%, with the balance being Fe and unavoidable impurities.

[0067] Experimental Example 1

[0068] The steel plates obtained in Examples 1-8 and Comparative Examples 1-3 were tested for mass wear according to the method described in GB / T 12444-2006 "Metallic Materials Wear Test Method - Test Ring-Block Sliding Wear Test". The pressure was 70 N, the grinding wheel speed was 200 rpm, the total number of revolutions was 2000 r, and the time was 10 min. The test results are shown in Table 1.

[0069] Table 1. Test results of abrasion resistance of steel plates

[0070]

[0071] As shown in Table 1, the wear resistance of the steel plates obtained in Examples 1-8 is lower than that in Comparative Examples 1-3, indicating that adding Si, Nb, Ti and V elements to the steel plate and limiting 2≤(Si+Nb) / (V+Ti)≤15 can improve the wear resistance of the steel plate.

[0072] Experiment Example 2

[0073] The tensile strength of the steel plates obtained in Examples 8 to 11 was tested according to the method described in GB / T 228.1-2021 "Metallic materials, tensile testing - Part 1: Test method at room temperature". The test results are shown in Table 2.

[0074] Table 2 Tensile strength test results of steel plates

[0075]

[0076] As shown in Table 2, the tensile strength of the steel plates obtained in Examples 12-13 is higher than that in Examples 8-11, indicating that the introduction of a CH4-CO2-N2 mixed gas with a volume ratio of 2:1:3-8 during heating can improve the tensile strength of the steel plate.

[0077] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high plasticity wear-resistant steel plate, characterized by, Consists of the following ingredients by weight percentage: C 0.18%-0.25%, Si 0.2%-0.6%, Mn 1.0%-1.5%, Nb 0.02%-0.05%, Ti 0.005%-0.03%, Cr 0.5%-1.0%, Mo 0.3%-0.6%, V 0.03%-0.1%, the balance being Fe and inevitable impurities; the ratio of Si+Nb to V+Ti is (Si+Nb) / (V+Ti)=0.44 / 0.07, and the weight ratio of V to Ti is 9:1; The smelting process of the high plasticity and toughness wear-resistant steel plate comprises the following steps: S1, after the ingredients are proportioned, a steel ingot is obtained through smelting and casting; S2, the steel ingot is heated, rolled and heat treated to obtain a high plasticity and toughness wear-resistant steel plate; In step S2, CH4-CO2-N2 mixed gas is introduced during heating; The volume ratio of CH4, CO2 and N2 in the CH4-CO2-N2 mixed gas is 2:1:3-8.

2. The smelting process of a high plastic and tough wear-resistant steel plate according to claim 1, characterized in that, The heating temperature is 1150-1200 DEG C, and the heating time is 1-2 h.

3. The smelting process of a high plastic and tough wear-resistant steel plate according to claim 1, characterized in that, The heat treatment comprises normalizing, quenching and tempering.

4. The smelting process of a high plastic and tough wear-resistant steel plate according to claim 3, characterized in that, The normalizing temperature is 880-900 DEG C, the normalizing time is 50-60 min; the quenching temperature is 870-900 DEG C, the quenching time is 50-60 min; the tempering temperature is 450-500 DEG C, and the tempering time is 1-2 h.

5. The smelting process of a high plastic and tough wear-resistant steel plate according to claim 3, characterized in that, The quenching cooling rate is 50-60 DEG C / s.

6. The smelting process of a high plastic and tough wear-resistant steel plate according to claim 1, characterized in that, The rolling open rolling temperature is 1080-1120 DEG C, and the finish rolling temperature is 810-830 DEG C.

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