High-strength and high-toughness steel as well as preparation method and application thereof

Abstract

The invention provides high-strength and high-toughness steel as well as a preparation method and application thereof, and belongs to the technical field of engineering machinery and protective steel. The high-strength and high-toughness steel provided by the invention comprises the following components in percentage by mass: 0.12-0.28% of C; 0.50% to 2.00% of Mn; si < = 0.40%; 0.50% to 2.00% of Cr; 0.50% to 3.00% of Ni; 0.10% to 0.85% of Mo; 0.01% to 0.35% of V or Nb; ti: 0.01 to 0.30%; b: 0.0010% to 0.0035% of the total weight of the raw 0.01 to 0.045 percent of Al; less than or equal to 0.025% of P; less than or equal to 0.015% of S and the balance of iron. The result of the embodiment shows that the yield strength of the high-strength and high-toughness steel is larger than or equal to 1100 MPa; the tensile strength is greater than or equal to 1250MPa; the elongation after fracture is greater than or equal to 10%, and the Charpy impact energy of a V-shaped notch at-40 DEG C is greater than or equal to 55J.

Description

technical field [0001] The invention relates to the technical field of engineering machinery and steel for protection, in particular to a high-strength and high-toughness steel and its preparation method and application. Background technique [0002] Protective performance is an important element of combat effectiveness of armored vehicles. Improving the survivability of armored vehicles on the battlefield is also the focus of the armies of various countries. Armored vehicles are vulnerable to landmines and simplified explosives. Therefore, improving the anti-detonation capability of armored vehicles on the battlefield has become a new generation of armored warfare Key content of vehicle development. On the other hand, with the development of construction machinery towards larger products, lighter weight, and heavier loads, the steel that is the basis of the whole machine needs to be lighter in weight and longer in cycle time, and the demand for high-strength steel with a yi...

AI Technical Summary

Problems solved by technology

For example, Patent 1 (Application No. 201810184084.7) announced a yield strength ≥ 1100MPa, tensile strength ≥ 1250MPa, elongation after fracture ≥ 12%, -40 ℃ Charpy V-notch sample impact energy ≥ 120J, and has excellent welding performance Ultra-fine-grained high-strength steel plate, but this patent has high requirements for phosphorus and sulfur content control (P≤0.005%, S≤0.002%), and puts forward high requirements for raw materials, equipment, operations, and processes, and it is difficult to promote; Patent 2 (application number 201610587785.6) discloses a high-strength steel with a yield strength of 1100MPa, a tensile strength ≥ 1200MPa, a Charpy impact energy at -40°C low temperature ≥ 30J, and a high-strength steel with good cold bending properties. However, the low-temperature impact toughness of the hot-rolled sheet prepared by this invention is not high, and cannot meet the energy absorption requirements of anti-detonation; Patent 3 (201110096170.0) provides a high-strength steel with a yield strength of 1100-1200MP and its manufacturing method. It is 1250~1340MPa. Although the yield strength of this patent reaches 1100MPa, the impact energy at -40°C is only 21~34J, which also cannot meet the anti-detonation requirements; Patent 4 (202011490752.2) provides a high-toughness 1300MPa ultra-high-strength steel And its manufacturing method, its tensile strength ≥ 1450MPa, but its elongation ≥ 9%, -40 ℃ low-temperature Charpy impact energy ≥ 30J, the energy absorption effect is limited, and the invention has adopted VD vacuum refining process in the manufacturing process, Strict requirements on steelmaking equipment and increased smelting costs

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