Steel plate with impact resistance and wear resistance and preparation method thereof

Abstract

The invention provides a steel plate with impact resistance and wear resistance and a preparation method thereof, and belongs to the technical field of steel plate materials. By adjusting the contents of C, Si, P, S and W and adding a certain amount of Mn, Cr, Ni, Mo and V elements, a stable solid solution or a compound including tungsten carbide is formed, and the impact resistance and wear resistance of the prepared steel plate are remarkably improved; nb and C form a high-hardness carbide, the strength and hardness of the steel are enhanced, and the yield strength and tensile strength of the steel can be remarkably improved through the niobium element; elements such as Ti and C are combined to form compounds such as titanium carbide (TiC), so that crystal grains of the steel can be refined, and the strength and toughness of the steel can be improved; te can refine steel grains and improve the toughness of the steel, so that the steel can better absorb energy when being impacted, all the components have a synergistic effect, grain boundary corrosion and intragranular corrosion are inhibited, and therefore the corrosion resistance of the steel is improved, the aging process of the steel is delayed, and the service life of the steel is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of steel plate materials, and in particular to a steel plate having both impact resistance and wear resistance and a preparation method thereof. Background Art

[0002] With the continuous advancement of technology, more and more special steels with high performance are being developed and produced for use in different industries. Wear-resistant steel plates are mainly used in the engineering machinery industry for wear-resistant working parts and structures of excavators, loaders, bulldozers, graders, large off-road dump trucks, electric wheels and other products, as well as equipment parts that need to be worn and eroded in the material transportation process in mining, mineral processing, docks, cement plants and steel plants, etc., and their consumption is extremely large. There are mainly the following types of impact-resistant steels: high manganese steel, alloy steel, carbon steel and some special stainless steels. These impact-resistant steels are widely used in the manufacture of bridges, highway guardrails, engineering machinery structural parts, protective equipment and other fields that need to withstand impact loads. At present, the special steels used in mining, loading, transportation and processing equipment mainly consider wear resistance and impact resistance.

[0003] Chinese patent CN119020675A discloses a high-strength, wear-resistant and impact-resistant special cast steel and its manufacturing process. The preparation process of the special cast steel of the invention is cumbersome and the operation steps are complicated. Chinese patent CN104131224A discloses a wear-resistant and impact-resistant alloy steel, which contains chemical elements and their mass percentages: carbon 0.55-0.68%, silicon 0.048-0.065%, manganese 0.02-0.05%, titanium 0.2-0.3%, aluminum 0.04-0.05%, gallium 0.004-0.0042%, nail 0.025-0.03%, tantalum 0.05-0.07%, tungsten 0.028-0.035%, cobalt 0.01-0.02%, silver 0.001-0.002%, sulfur ≤0.035%, phosphorus 0.58-0.62%, and the balance is iron. The P content in this invention is high, and P will reduce the low-temperature impact toughness of the steel plate while improving corrosion resistance, and increase the risk of cold brittleness. Summary of the invention

[0004] The purpose of the present invention is to provide a steel plate with both impact resistance and wear resistance. The steel plate provided by the present invention has excellent impact resistance and wear resistance, and meets the demand for special steel materials on mining, loading, transportation and processing equipment.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The invention provides a steel plate with both impact resistance and wear resistance. The steel plate with both impact resistance and wear resistance comprises the following chemical components in mass percentage: C: 0.70-1.40%, Si: 0.20-0.50%, Mn: 0.8-1.60%, P: 0.02-0.030%, S: 0.01-0.020%, Cr: 0.40-0.60%, Ni: 0.30-0.50%, Mo: 0.70-1.20%, V: 0.30-0.50%, W: 2.0-2.5%, Nb: 0.05-0.08%, Ti: 0.01-0.025%, Te: 0.02-0.03%, and the rest is Fe and inevitable impurities.

[0007] Preferably, the steel plate having both impact resistance and wear resistance comprises the following chemical components in mass percentage: C: 0.80-1.30%, Si: 0.25-0.40%, Mn: 0.9-1.50%, P: 0.023-0.028%, S: 0.015-0.018%, Cr: 0.45-0.57%, Ni: 0.35-0.46%, Mo: 0.80-1.10%, V: 0.35-0.47%, W: 2.1-2.4%, Nb: 0.055-0.07%, Ti: 0.01-0.025%, Te: 0.022-0.028%, and the rest are Fe and unavoidable impurities.

[0008] The present invention also provides a method for preparing the steel plate having both impact resistance and wear resistance as described in the above technical solution, comprising the following steps:

[0009] The continuously cast slab is straightened, rolled and cooled in sequence to obtain a cooled steel plate;

[0010] The straightened steel plate is sequentially subjected to quenching, tempering and annealing treatments to obtain a steel plate having both impact resistance and wear resistance.

[0011] Preferably, the straightening is to use a hot straightening machine to straighten the shape of the steel plate; the final straightening temperature of the straightening is ≥800°C.

[0012] Preferably, the rolling is three-pass rolling; the pre-rolling temperature of the rolling is 920-1000°C, and the final rolling temperature of the rolling is preferably 800-890°C.

[0013] Preferably, the cooling is water cooling, the cooling rate of the water cooling is 2-3°C / s, and the final cooling temperature of the cooling is ≥750°C.

[0014] Preferably, the temperature of the quenching treatment is 700-750° C., and the time of the quenching treatment is 50-100 min.

[0015] Preferably, the tempering temperature is 400-500° C., and the tempering time is 40-80 min.

[0016] Preferably, the annealing treatment includes: first, in the first stage, the temperature is increased to 540-620°C at a heating rate of 2-4°C / min, and kept warm for 25-30min; then in the second stage, the temperature is increased to 740-820°C at a heating rate of 5°C / min; then in the third stage, the temperature is increased to 890-950°C at a heating rate of 5°C / min, and kept warm for 10-20min, and finally cooled to 660°C in the annealing furnace and then air-cooled.

[0017] Preferably, the annealing treatment further includes stacking slow cooling.

[0018] The present invention provides a steel plate with both impact resistance and wear resistance. By adjusting the contents of C, Si, P, S and W and adding a certain amount of Mn, Cr, Ni, Mo and V elements, a stable solid solution or a compound including tungsten carbide is formed, thereby significantly improving the impact resistance and wear resistance of the prepared steel plate. In addition, adding a certain amount of Nb can form a high-hardness carbide with C to enhance the strength and hardness of the steel. Niobium can significantly improve the yield strength and tensile strength of the steel through fine grain strengthening and precipitation strengthening mechanisms. Ti can be combined with C and other elements to form a high-hardness carbide with C and a high-hardness carbide with C. The formation of compounds such as titanium carbide (TiC) can refine the grains of steel, improve the strength and toughness of steel, and the titanium element can significantly improve the low-temperature impact toughness of steel, so that the steel can still maintain good mechanical properties in a low-temperature environment; adding a certain amount of Te can refine the grains of steel, improve the toughness of steel, and enable the steel to better absorb energy when impacted, further improving the impact resistance. The various components work synergistically to inhibit intergranular corrosion and intragranular corrosion, thereby improving the corrosion resistance of steel, delaying the aging process of steel, improving the oxidation resistance of steel, and extending the service life of the prepared steel plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The present invention is a flow chart for preparing a steel plate having both impact resistance and wear resistance. DETAILED DESCRIPTION

[0020] The invention provides a steel plate with both impact resistance and wear resistance. The steel plate with both impact resistance and wear resistance comprises the following chemical components in mass percentage: C: 0.70-1.40%, Si: 0.20-0.50%, Mn: 0.8-1.60%, P: 0.02-0.030%, S: 0.01-0.020%, Cr: 0.40-0.60%, Ni: 0.30-0.50%, Mo: 0.70-1.20%, V: 0.30-0.50%, W: 2.0-2.5%, Nb: 0.05-0.08%, Ti: 0.01-0.025%, Te: 0.02-0.03%, and the rest is Fe and inevitable impurities.

[0021] In the present invention, unless otherwise specified, the raw materials used are conventional commercial products in the art.

[0022] In the present invention, the steel plate having both impact resistance and wear resistance preferably includes the following chemical components in mass percentage: C: 0.80-1.30%, Si: 0.25-0.40%, Mn: 0.9-1.50%, P: 0.023-0.028%, S: 0.015-0.018%, Cr: 0.45-0.57%, Ni: 0.35-0.46%, Mo: 0.80-1.10%, V: 0.35-0.47%, W: 2.1-2.4%, Nb: 0.055-0.07%, Ti: 0.01-0.025%, Te: 0.022-0.028%, and the rest is Fe and unavoidable impurities.

[0023] The present invention also provides a method for preparing the steel plate having both impact resistance and wear resistance as described in the above technical solution, comprising the following steps:

[0024] The continuously cast slab is straightened, rolled and cooled in sequence to obtain a cooled steel plate;

[0025] The straightened steel plate is sequentially subjected to quenching, tempering and annealing treatments to obtain a steel plate having both impact resistance and wear resistance.

[0026] In the present invention, the straightening is preferably performed by using a hot straightening machine to straighten the steel plate shape; the final straightening temperature is preferably ≥ 800° C., more preferably 850-930° C. The present invention eliminates shape defects of the steel plate through straightening, which facilitates smooth subsequent processing.

[0027] In the present invention, the rolling is preferably five-pass rolling; the pre-rolling temperature of the rolling is preferably 920-1000°C, and the final rolling temperature of the rolling is preferably 800-890°C. In the present invention, during the rolling process, the reduction amounts of the first and second passes are independently 5-8%, and the reduction amounts of the third to fifth passes are independently 9-12%. The present invention controls the rolling parameters within the above range to achieve precise control of the size and shape of the steel plate, refine the grains, improve the uniformity of the structure, and prepare for subsequent further hot processing.

[0028] In the present invention, the cooling is preferably water cooling, the cooling rate of the water cooling is 2-3°C / s, and the final cooling temperature of the cooling is ≥750°C. The present invention reduces the generation of oxide scale after rolling through cooling, further refines the grains of the steel and changes its internal structure, so that the yield strength and tensile strength of the steel are significantly improved, the good toughness of the steel is maintained, the occurrence of brittle fracture is avoided, the wear resistance of the steel plate is improved, and the service life is extended.

[0029] In the present invention, the temperature of the quenching treatment is preferably 700-750°C, and the time of the quenching treatment is preferably 50-100 minutes. The present invention controls the parameters of the quenching treatment within the above range to transform the austenite phase in the steel plate into the martensite phase, making the crystal structure of the steel more compact, thereby significantly improving the hardness and strength of the steel plate, thereby improving the wear resistance of the steel plate.

[0030] In the present invention, the tempering temperature is preferably 400-500°C, and the tempering time is preferably 40-80 minutes. The present invention can eliminate the internal stress generated during the quenching process through tempering, so that the toughness of the steel is restored and improved. At the same time, tempering can also improve the plasticity of the steel plate, making it less likely to break when subjected to external forces, thereby increasing the flexibility of its processing and use.

[0031] In the present invention, the annealing treatment preferably includes: first, in the first stage, the temperature is increased to 540-620°C at a heating rate of 2-4°C / min, and the temperature is kept for 25-30min; then in the second stage, the temperature is increased to 740-820°C at a heating rate of 5°C / min; then in the third stage, the temperature is increased to 890-950°C at a heating rate of 5°C / min, and the temperature is kept for 10-20min, and finally cooled to 660°C in the annealing furnace and then air-cooled. The present invention controls the parameters of the annealing treatment within the above range, so that the residual stress inside the steel plate is released, and the structural defects inside the steel plate, such as inclusions, segregation, etc., are eliminated, and the steel plate structure is further made more uniform and stable.

[0032] In the present invention, the annealing treatment preferably further includes stacking slow cooling

[0033] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] Figure 1 A flow chart for preparing a steel plate having both impact resistance and wear resistance provided by the present invention.

[0035] Example 1

[0036] A steel plate having both impact resistance and wear resistance, composed of the following chemical components in mass percentage: C: 0.90%, Si: 0.29%, Mn: 0.9%, P: 0.023%, S: 0.016%, Cr: 0.49%, Ni: 0.39%, Mo: 0.85%, V: 0.37%, W: 2.2%, Nb: 0.065%, Ti: 0.02%, Te: 0.023%, and the rest being Fe and inevitable impurities.

[0037] The method for preparing the above-mentioned steel plate having both impact resistance and wear resistance comprises the following steps:

[0038] The continuous casting slab is straightened into a steel plate shape by a hot straightening machine, and then rolled and water-cooled to obtain a cooled steel plate;

[0039] The rolling process is five-pass rolling; the pre-rolling temperature is 950°C, and the final rolling temperature is 880°C; the reduction in the first and second passes is 7%, and the reduction in the third to fifth passes is 10%. The cooling rate of the water cooling is 3°C / s, and the final cooling temperature is 780°C

[0040] The straightened steel plate is kept at 740°C for 60 minutes, oil quenched after being taken out of the furnace, and then kept at 500°C for 30 minutes. After annealing and stacking slow cooling, a steel plate with both impact resistance and wear resistance is obtained.

[0041] The annealing treatment is as follows: first, in the first stage, the temperature is increased to 600°C at a heating rate of 4°C / min and kept at this temperature for 30 minutes; then in the second stage, the temperature is increased to 800°C at a heating rate of 5°C / min; then in the third stage, the temperature is increased to 930°C at a heating rate of 5°C / min and kept at this temperature for 20 minutes, and finally, the temperature is cooled to 660°C in the annealing furnace and then air-cooled.

[0042] Example 2

[0043] The steel plate with both impact resistance and wear resistance of Example 2 was prepared according to the method of Example 1, and the difference from Example 1 is:

[0044] The annealing treatment is as follows: first, in the first stage, the temperature is increased to 620°C at a heating rate of 4°C / min and kept at this temperature for 30 minutes; then in the second stage, the temperature is increased to 820°C at a heating rate of 5°C / min; then in the third stage, the temperature is increased to 950°C at a heating rate of 5°C / min and kept at this temperature for 20 minutes, and finally, the temperature is cooled to 660°C in the annealing furnace and then air-cooled.

[0045] Example 3

[0046] The steel plate with both impact resistance and wear resistance of Example 3 was prepared according to the method of Example 1, and the difference from Example 1 is:

[0047] The annealing treatment is as follows: first, in the first stage, the temperature is increased to 580°C at a heating rate of 4°C / min and kept at this temperature for 30 minutes; then in the second stage, the temperature is increased to 780°C at a heating rate of 5°C / min; then in the third stage, the temperature is increased to 900°C at a heating rate of 5°C / min and kept at this temperature for 20 minutes, and finally, the temperature is cooled to 660°C in the annealing furnace and then air-cooled.

[0048] Example 4

[0049] A steel plate having both impact resistance and wear resistance, composed of the following chemical components in mass percentage: C: 1.10%, Si: 0.29%, Mn: 1.20%, P: 0.023%, S: 0.016%, Cr: 0.53%, Ni: 0.42%, Mo: 0.95%, V: 0.42%, W: 2.3%, Nb: 0.067%, Ti: 0.015%, Te: 0.025%, and the rest being Fe and inevitable impurities.

[0050] The steel plate with both impact resistance and wear resistance of Example 4 was prepared according to the method of Example 2.

[0051] Example 5

[0052] A steel plate having both impact resistance and wear resistance, composed of the following chemical components in mass percentage: C: 1.20%, Si: 0.32%, Mn: 1.4%, P: 0.023%, S: 0.016%, Cr: 0.56%, Ni: 0.46%, Mo: 0.99%, V: 0.45%, W: 2.4%, Nb: 0.065%, Ti: 0.015%, Te: 0.025%, and the rest being Fe and inevitable impurities.

[0053] The steel plate having both impact resistance and wear resistance of Example 5 was prepared according to the method of Example 2.

[0054] The properties of the steel plates prepared in Examples 1 to 5 were tested and the results are shown in Table 1.

[0055] Table 1 Performance statistics of steel plates with both impact resistance and wear resistance prepared in Examples 1 to 5

[0056]

[0057] In summary, the steel plate provided in Example 5 of the present invention has a yield strength of 1824 MPa, a tensile strength of 1971 MPa, a wear resistance of 5.1 times that of Q345 low alloy steel, an elongation of 19.0%, an average impact energy (transverse, -40°C) of 61 J, and excellent impact resistance and wear resistance.

[0058] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A steel plate having both impact resistance and wear resistance, characterized in that: The steel plate having both impact resistance and wear resistance comprises the following chemical components in mass percentage: C: 0.70-1.40%, Si: 0.20-0.50%, Mn: 0.8-1.60%, P: 0.02-0.030%, S: 0.01-0.020%, Cr: 0.40-0.60%, Ni: 0.30-0.50%, Mo: 0.70-1.20%, V: 0.30-0.50%, W: 2.0-2.5%, Nb: 0.05-0.08%, Ti: 0.01-0.025%, Te: 0.02-0.03%, and the rest is Fe and unavoidable impurities.

2. The steel plate having both impact resistance and wear resistance as claimed in claim 1, characterized in that: The steel plate having both impact resistance and wear resistance comprises the following chemical components in mass percentage: C: 0.80-1.30%, Si: 0.25-0.40%, Mn: 0.9-1.50%, P: 0.023-0.028%, S: 0.015-0.018%, Cr: 0.45-0.57%, Ni: 0.35-0.46%, Mo: 0.80-1.10%, V: 0.35-0.47%, W: 2.1-2.4%, Nb: 0.055-0.07%, Ti: 0.01-0.025%, Te: 0.022-0.028%, and the rest is Fe and unavoidable impurities.

3. A method for preparing a steel plate having both impact resistance and wear resistance as claimed in claim 1 or 2, characterized in that: The following steps are involved: The continuously cast slab is straightened, rolled and cooled in sequence to obtain a cooled steel plate; The straightened steel plate is sequentially subjected to quenching, tempering and annealing treatments to obtain a steel plate having both impact resistance and wear resistance.

4. The preparation method according to claim 3, characterized in that: The straightening is to use a hot straightening machine to straighten the shape of the steel plate; the final straightening temperature of the straightening is ≥800°C.

5. The preparation method according to claim 3, characterized in that: The rolling is performed in three passes; the pre-rolling temperature of the rolling is 920-1000°C, and the final rolling temperature of the rolling is preferably 800-890°C.

6. The preparation method according to claim 3, characterized in that: The cooling is water cooling, the cooling rate of the water cooling is 2-3°C / s, and the final cooling temperature of the cooling is ≥750°C.

7. The preparation method according to claim 3, characterized in that: The temperature of the quenching treatment is 700-750° C., and the time of the quenching treatment is 50-100 minutes.

8. The preparation method according to claim 3, characterized in that: The tempering temperature is 400-500° C., and the tempering time is 40-80 minutes.

9. The preparation method according to claim 3, characterized in that: The annealing treatment includes: first, in the first stage, the temperature is increased to 540-620°C at a heating rate of 2-4°C / min, and the temperature is kept for 25-30 minutes; then in the second stage, the temperature is increased to 740-820°C at a heating rate of 5°C / min; then in the third stage, the temperature is increased to 890-950°C at a heating rate of 5°C / min, and the temperature is kept for 10-20 minutes, and finally, it is cooled to 660°C in the annealing furnace and then air-cooled.

10. The preparation method according to claim 3, characterized in that: The annealing treatment also includes stacking and slow cooling.

Images