High-ductility and high-toughness wear-resistant steel plate and smelting process thereof

Abstract

The invention relates to the technical field of steel and iron smelting, and provides a high-ductility and high-toughness wear-resistant steel plate and a smelting process thereof.The high-ductility and high-toughness wear-resistant steel plate is composed of, by weight, 0.18%-0.25% of C, 0.2%-0.6% of Si, 1.0%-1.5% of Mn, 0.02%-0.05% of Nb, 0.005%-0.03% of Ti, 0.5%-1.0% of Cr, 0.3%-0.6% of Mo, 0.03%-0.1% of V and the balance Fe and inevitable impurities; the ratio of Si + Nb to V + Ti is 2 < = (Si + Nb) / (V + Ti) < = 15. By means of the technical scheme, the problem that in the prior art, steel plates are poor in abrasion resistance is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of steel smelting, and in particular to a high-plasticity and toughness wear-resistant steel plate and a smelting process thereof. Background Art

[0002] In the modern industrial system, wear-resistant steel plates, as a key foundational material, play an irreplaceable role in numerous fields. Their applications range from excavator buckets and bulldozer blades in the construction machinery sector to crusher liners and scraper conveyors in mining machinery, and even coal mill liners in the power industry. With the continuous development of industry, the performance requirements for wear-resistant steel plates are becoming increasingly stringent. Not only are they expected to possess excellent wear resistance to extend equipment life and reduce maintenance costs, but they also place higher standards on plasticity and toughness to meet the demands of forming, processing, and impact resistance in complex working conditions.

[0003] Currently, conventional wear-resistant steel plates have limitations in both production processes and performance. Improving wear resistance is often achieved by increasing the carbon content or adding large amounts of alloying elements. However, increasing carbon content significantly reduces the steel's plasticity and toughness, making it more susceptible to brittle fracture under stress. Therefore, developing wear-resistant steel plates with high plasticity and toughness is of great significance. Summary of the Invention

[0004] The present invention provides a high-plasticity and toughness wear-resistant steel plate and a smelting process thereof, which solves the problem of poor wear resistance of the steel plate in the related art.

[0005] The technical solutions of the present invention are as follows: The present invention provides a high-plasticity and toughness wear-resistant steel plate, which is composed of the following components, 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%, and the balance is Fe and inevitable impurities; the ratio of Si+Nb to V+Ti is: 2≤(Si+Nb) / (V+Ti)≤15.

[0006] As a further technical solution, the weight ratio of the V to the Ti is 6-9:1.

[0007] In the present invention, Ti, V, and C in the steel plate form carbides, wherein Ti carbides are preferentially precipitated in the molten steel, and V carbides grow on the basis of Ti carbides to form composite carbide particles. By controlling the weight ratio of V to Ti to be 6 to 9:1, the carbide particle sizes can be more evenly distributed, forming a dense dispersion-strengthened phase in the steel matrix, thereby improving the wear resistance of the steel plate. The carbides generated by Ti and V can effectively inhibit grain boundary migration and grain growth, and the refined grains can reduce surface plastic deformation of the steel plate, thereby improving wear resistance.

[0008] The present invention also provides a smelting process for a high-plasticity and toughness wear-resistant steel plate, which is used to prepare the high-plasticity and toughness wear-resistant steel plate, comprising the following steps: S1, after preparing the materials according to the ingredients, smelting and casting to obtain a steel ingot; S2. The steel ingot is heated, rolled, and heat-treated to obtain a high-plasticity, toughness, and wear-resistant steel plate.

[0009] As a further technical solution, in step S2, a CH4-CO2-N2 mixed gas is introduced during heating.

[0010] In the present invention, a CH4-CO2-N2 mixed gas is introduced under a high-temperature heating environment. The gas reacts with the molten steel to generate active atoms and dissolves in the molten steel. After dissolving into the ferrite lattice, it exists 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 dislocation movement, thereby improving the strength of the steel plate.

[0011] 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.

[0012] In the present 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 elements dissolved can be accurately controlled, thereby further improving the strength of the steel plate.

[0013] As a further technical solution, the heating temperature is 1150-1200° C., and the heating time is 1-2 hours.

[0014] As a further technical solution, the heat treatment includes normalizing, quenching and tempering.

[0015] 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.

[0016] As a further technical solution, the cooling rate of the quenching is 50-60°C / s.

[0017] As a further technical solution, the starting rolling temperature is 1080~1120℃, and the finishing rolling temperature is 810~830℃.

[0018] The working principle and beneficial effects of the present invention are: In the present invention, by adding Si, Nb, Ti and V elements to the steel and limiting the ratio to 3≤(Si+Nb) / (V+Ti)≤15, grain growth can be hindered during the solidification and cooling process of the steel, thereby refining the grains and improving the strength and hardness of the steel. In addition, carbide particles generated by the addition of Si and Nb with carbon are distributed in the steel matrix, thereby enhancing the precipitation strengthening effect of the steel and improving the wear resistance of the steel plate. DETAILED DESCRIPTION

[0019] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0020] In the following examples and comparative examples: Ferrosilicon alloy, silicon content 75wt%; ferromanganese alloy, manganese content 68wt%; ferrochromium alloy, chromium content 60wt%; ferrotitanium alloy, titanium content 80wt%; ferromolybdenum alloy, molybdenum content 70wt%; ferrovanadium alloy, vanadium content 50wt%; ferroniobium alloy, niobium content 40wt%.

[0021] Example 1 High plasticity and toughness wear-resistant steel plate, composed of the following components by weight percentage: C 0.18%, Si 0.2%, Mn 1.0%, Nb 0.02%, Ti 0.01%, Cr 0.5%, Mo 0.3%, V 0.1%, the balance being Fe and unavoidable impurities; A smelting process for high-plasticity and toughness wear-resistant steel plate comprises the following steps: S1. Mixing iron blocks, carbon powder, ferrosilicon alloy, ferromanganese alloy, ferrochrome alloy, ferrotitanium alloy, ferroniobium alloy, ferrochrome alloy, ferromolybdenum alloy, and ferrovanadium alloy according to the ingredients, and smelting and casting to obtain steel ingots; S2. Heat the steel ingot to 1150°C in a CO2 atmosphere, keep it warm for 2 hours, roll it at 1080°C, and set the final rolling temperature to 810°C. Normalize it at 880°C for 60 minutes, quench it at 870°C, keep it warm for 60 minutes, and then cool it to room temperature at a rate of 50°C / s. Temper it at 450°C for 2 hours to obtain a high plasticity, toughness and wear-resistant steel plate.

[0022] Example 2 High plasticity and toughness wear-resistant steel plate, 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%, the balance being Fe and unavoidable impurities; A smelting process for high-plasticity and toughness wear-resistant steel plate comprises the following steps: S1. Mixing iron blocks, carbon powder, ferrosilicon alloy, ferromanganese alloy, ferrochrome alloy, ferrotitanium alloy, ferroniobium alloy, ferrochrome alloy, ferromolybdenum alloy, and ferrovanadium alloy according to the ingredients, and smelting and casting to obtain steel ingots; S2. The steel ingot is heated to 1170°C in a CO2 atmosphere and kept warm for 2 hours. The steel ingot is rolled at 1100°C with a final rolling temperature of 820°C. The steel ingot is normalized at 890°C for 60 minutes and quenched at 890°C. After being kept warm for 60 minutes, the steel ingot is cooled to room temperature at a rate of 55°C / s. The steel ingot is tempered at 470°C for 2 hours to obtain a high plasticity, toughness and wear-resistant steel plate.

[0023] Example 3 High plasticity and toughness wear-resistant steel plate, 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%, the balance being Fe and unavoidable impurities; A smelting process for high-plasticity and toughness wear-resistant steel plate comprises the following steps: S1. Mixing iron blocks, carbon powder, ferrosilicon alloy, ferromanganese alloy, ferrochrome alloy, ferrotitanium alloy, ferroniobium alloy, ferrochrome alloy, ferromolybdenum alloy, and ferrovanadium alloy according to the ingredients, and smelting and casting to obtain steel ingots; S2. Heat the steel ingot to 1200°C in a CO2 atmosphere, keep it warm for 1 hour, roll it at 1120°C, and set the final rolling temperature to 830°C. Normalize it at 900°C for 50 minutes, quench it at 900°C, keep it warm for 50 minutes, and then cool it to room temperature at a rate of 60°C / s. Temper it at 500°C for 1 hour to obtain a high plasticity, toughness and wear-resistant steel plate.

[0024] Example 4 The only difference between this embodiment and embodiment 2 is that the high plasticity and toughness wear-resistant steel plate is composed of the following components, by weight percentage: C 0.22%, Si 0.2%, Mn 1.2%, Nb 0.02%, Ti 0.02%, Cr 0.7%, Mo 0.5%, V 0.05%, and the balance is Fe and unavoidable impurities.

[0025] Example 5 The only difference between this embodiment and embodiment 2 is that the high plasticity and toughness wear-resistant steel plate is composed of the following components, by weight percentage: C 0.22%, Si 0.6%, Mn 1.2%, Nb 0.05%, Ti 0.02%, Cr 0.7%, Mo 0.5%, V 0.05%, and the balance is Fe and unavoidable impurities.

[0026] Example 6 The only difference between this embodiment and embodiment 2 is that the high plasticity and toughness wear-resistant steel plate is composed of the following components, by weight percentage: C 0.22%, Si 0.4%, Mn 1.2%, Nb 0.04%, Ti 0.005%, Cr 0.7%, Mo 0.5%, V 0.065%, and the balance is Fe and unavoidable impurities.

[0027] Example 7 The only difference between this embodiment and embodiment 2 is that the high plasticity and toughness wear-resistant steel plate is composed of the following components, by weight percentage: C 0.22%, Si 0.4%, Mn 1.2%, Nb 0.04%, Ti 0.01%, Cr 0.7%, Mo 0.5%, V 0.06%, and the balance is Fe and unavoidable impurities.

[0028] Example 8 The only difference between this embodiment and Example 2 is that the high plasticity and toughness wear-resistant steel plate is composed of the following components, by weight percentage: C 0.22%, Si 0.4%, Mn 1.2%, Nb 0.04%, Ti 0.007%, Cr 0.7%, Mo 0.5%, V 0.063%, and the balance is Fe and unavoidable impurities.

[0029] Example 9 The only difference between this embodiment and embodiment 8 is that the heating atmosphere is a CH4-CO2 mixed gas with a volume ratio of 2:1.

[0030] Example 10 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.

[0031] Example 11 The only difference between this embodiment and embodiment 10 is that the volume ratio of CH4-CO2-N2 is 2:1:10.

[0032] Example 12 The only difference between this embodiment and embodiment 10 is that the volume ratio of CH4-CO2-N2 is 2:1:3.

[0033] Example 13 The only difference between this embodiment and embodiment 10 is that the volume ratio of CH4-CO2-N2 is 2:1:8.

[0034] Comparative Example 1 The only difference between this comparative example and Example 1 is that the high plasticity and toughness wear-resistant steel plate consists of the following components, by weight percentage: C 0.18%, Si 0.2%, Mn 1.0%, Nb 0.02%, Ti 0.03%, Cr 0.5%, Mo 0.3%, V 0.1%, and the balance is Fe and unavoidable impurities.

[0035] Comparative Example 2 The only difference between this comparative example and Example 1 is that the high plasticity and toughness wear-resistant steel plate consists of the following components, by weight percentage: C 0.18%, Si 0.2%, Mn 1.0%, Nb 0.02%, Ti 0.04%, Cr 0.5%, Mo 0.3%, and the balance is Fe and unavoidable impurities.

[0036] Comparative Example 3 The only difference between this comparative example and Example 1 is that the high plasticity and toughness wear-resistant steel plate consists of the following components, by weight percentage: C 0.18%, Si 0.2%, Mn 1.0%, Nb 0.02%, Cr 0.5%, Mo 0.3%, V 0.04%, and the balance is Fe and unavoidable impurities.

[0037] Experimental Example 1 The steel plates prepared in Examples 1 to 8 and Comparative Examples 1 to 3 were tested for mass wear according to the method described in GB / T 12444-2006 "Wear test methods for metallic materials - Test ring-test block sliding wear test", with a pressure of 70 N, a grinding wheel speed of 200 rpm, a total number of revolutions of 2000 r, and a time of 10 min. The test results are shown in Table 1.

[0038] Table 1 Steel plate wear resistance test results

[0039] As can be seen from Table 1, the mass wear of the steel plates prepared in Examples 1 to 8 is lower than that in Comparative Examples 1 to 3, indicating that the wear resistance of the steel plates can be improved by adding Si, Nb, Ti, and V elements to the steel plates and limiting the ratio of 2≤(Si+Nb) / (V+Ti)≤15.

[0040] Experimental Example 2 The steel plates prepared in Examples 8 to 11 were tested for tensile strength according to the method described in GB / T 228.1-2021 “Tensile tests on metallic materials - Part 1: Room temperature test methods”. The test results are shown in Table 2.

[0041] Table 2 Steel plate tensile strength test results

[0042] As can be seen from Table 2, the tensile strength of the steel plates prepared in Examples 12 to 13 is higher than that in Examples 8 to 11, indicating that the tensile strength of the steel plates can be improved by introducing a CH4-CO2-N2 mixed gas with a volume ratio of 2:1:3 to 8 during heating.

[0043] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A high plasticity and toughness wear-resistant steel plate, characterized in that: The invention comprises the following components 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 is Fe and unavoidable impurities; the ratio of Si+Nb to V+Ti is: 2≤(Si+Nb) / (V+Ti)≤15.

2. The high plasticity and toughness wear-resistant steel plate according to claim 1, characterized in that: The weight ratio of the V to the Ti is 6-9:

1.

3. A smelting process for high-ductility wear-resistant steel plate, used for preparing a high-ductility wear-resistant steel plate as claimed in any one of claims 1 to 2, characterized in that: The following steps are involved: S1, after preparing the materials according to the ingredients, smelting and casting to obtain a steel ingot; S2. The steel ingot is heated, rolled, and heat-treated to obtain a high-plasticity, toughness, and wear-resistant steel plate.

4. The smelting process of a high plasticity and toughness wear-resistant steel plate according to claim 3, characterized in that: In step S2, during heating, a CH4-CO2-N2 mixed gas is introduced.

5. The smelting process of a high plasticity and toughness wear-resistant steel plate according to claim 4, characterized in that: The volume ratio of CH4, CO2 and N2 in the CH4-CO2-N2 mixed gas is 2:1:3~8.

6. The smelting process of a high plasticity and toughness wear-resistant steel plate according to claim 3, characterized in that: The heating temperature is 1150-1200° C., and the heating time is 1-2 hours.

7. The smelting process of a high plasticity and toughness wear-resistant steel plate according to claim 3, characterized in that: The heat treatment includes normalizing, quenching and tempering.

8. The smelting process of a high plasticity and toughness wear-resistant steel plate according to claim 7, characterized in that: The normalizing temperature is 880-900°C, and the normalizing time is 50-60 minutes; the quenching temperature is 870-900°C, and the quenching time is 50-60 minutes; the tempering temperature is 450-500°C, and the tempering time is 1-2 hours.

9. The smelting process of a high-ductility wear-resistant steel plate according to claim 7, characterized in that: The cooling rate of the quenching is 50-60°C / s.

10. The smelting process of a high-ductility wear-resistant steel plate according to claim 3, characterized in that: The starting rolling temperature is 1080-1120°C, and the finishing rolling temperature is 810-830°C.

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