Steel for wind power yaw bearing ring and heat treatment method

Abstract

The invention discloses steel for a wind power yaw bearing ring. The steel comprises the following chemical components of, in percentage by mass, 0.44 to 0.45% of C, 0.30 to 0.35% of Si, 0.60 to 0.70%of Mn, 0.16 to 0.18% of Mo, 0.50 to 0.60% of Ni, 1.10 to 1.20% of Cr, 0.0020 to 0.0021% of B, 0.028 to 0.030% of A1 acid solution, 0.09 to 0.10% of V, N less than or equal to 0.002%, O less than or equal to 0.0005%, H less than or equal to 0.00010%, S less than or equal to 0.003%, P less than or equal to 0.008% and the balance Fe and a small amount of impurities. The heat treatment method comprises the following steps that feeding is carried out according to design components, smelting is carried out, casting into a cast ingot is carried out, forging into a forging stock is carried out, the forging material is processed into the wind power yaw bearing ring, heating is carried out to 850 + / -2 DEG C, the temperature is kept for 3-4 hours, austenitizing is carried out, oil quenching is carried out, heating is carried out to 640 DEG C, the temperature is kept for 3 hours, oil cooling is carried out on the material to room temperature; and then surface induction heating quenching is carried out, the heating speed is 85-90 DEG C / s, the heating temperature is 945 DEG C, heat preservation is carried out for 3 s, and then quenching is carried out to the room temperature at the cooling speed of 50-80 DEG C / s. According to the formula, V and Al alloy elements are added, the N content is controlled, and the generation of VN is prevented by utilizing the N fixing effect of the Al element,so that V exists in austenite in a solid solution state, and the hardenability of the steel is improved.

Description

technical field [0001] The invention relates to an alloy steel and a heat treatment method thereof, in particular to a steel for wind power yaw bearing rings and a heat treatment method thereof. Background technique [0002] As a renewable green energy, wind energy is increasingly favored by countries all over the world. In recent years, the development of high-power wind turbines has put forward higher requirements for bearing rings. At present, the key components of generators mainly rely on imports. The research and development of bearing ring materials is an important way to reduce production costs, and there are still deficiencies in the heat treatment process of steel for high-power bearing rings. The low hardenability of the parts in the heat treatment process is An important cause of internally generated defects. In addition, the heat treatment process needs to be further optimized to improve the plasticity, toughness and low temperature impact resistance of the pr...

AI Technical Summary

Problems solved by technology

At present, the key components of generators mainly rely on imports. The research and development of bearing ring materials is an important way to reduce production costs, and there are still deficiencies in the heat treatment process of steel for high-power bearing rings. The low hardenability of the parts in the heat treatment process is Important Causes of Internally Generated Defects