Low temperature resistant wind power flange steel with high welding performance and high strength

Abstract

The invention discloses a low temperature resistant wind power flange steel with high welding performance and high strength, comprising the following chemical components in percentage by weight: 0.13-0.18% of C, 0.17-0.40% of Si, 1.30-1.45% of Mn, 0.035-0.060 of V, 0.03-0.05% of Nb, 0.015-0.030% of Al, 0.010-0.020% of Ti, not more than 0.005% of S, not more than 0.015% of P, not more than 0.04% of As, not more than 0.0020% of [O], 0.0060-0.0110% of [N], not more than 0.0002% of [H] and the balance of Fe; meanwhile, the required carbon equivalent (CEV) of the material is 0.40-0.43%. After the normalizing treatment, a flange made of the steel of the invention has the following performances: 500-570 MPa of tensile strength Rm, 325-360 MPa of yield strength Re1, 28-39% of elongation A5 and 76-85% of reduction rate of cross section; at the temperature of -50 DEG C, the impact energy AKv of the V-shaped nick is 110-180 Joules. The invention has the advantages of good welding performance, stable low temperature impact performance and higher strength.

Description

Technical field:

[0001] The invention relates to alloy steel in the iron and steel industry, in particular to the design of steel types for wind power flanges with low temperature resistance, high welding performance and high strength. Background technique:

[0002] At present, the international community is increasingly aware of the seriousness of environmental pollution and global warming. The "Kyoto Protocol" has formulated emission reduction plans and schedules. Countries have taken measures to try to curb the deterioration of environmental problems, one of which is to support the development of clean new energy.

[0003] With the rapid development of the wind power industry, the demand for steel for wind power has also increased significantly. In 2006, my country produced 100,000 tons of steel for wind power, an increase of 42.9% compared to 2005; in 2007, my country produced 150,000 tons of steel for wind power, an increase of 50% compared with 2006; In 2007, it incre...

Examples

Embodiment 1

[0028] Prepared by the following production process:

[0029] After smelting in a conventional converter or electric furnace, it is refined in a refining device, and barium microalloying and final deoxidation are performed in the later stage of refining. After the refining composition is adjusted, RH / VD is used for degassing and inclusion removal, and RH / VD can also be used for degassing and inclusion removal before LF refining. The invention can significantly improve the cleanliness of the steel through the RH / VD process, thereby significantly improving the strength and toughness of the steel and increasing the fatigue life of the material.

[0030] The chemical composition of the resulting steel:

[0031] C 0.17%, Si 0.32%, Mn 1.38%, Nb 0.039%, V 0.048%, Al 0.022%, Ti 0.015%, S 0.0030%, P 0.010%, As 0.008%, [O] 0.0016%, [ N] 0.0090%, [H] 0.00008%, the rest is Fe.

[0032] The carbon equivalent CEV of the obtained steel was 0.41%.

[0033] Ring rolling specifications: 420...

Embodiment 2

[0036] C 0.15%, Si 0.29%, Mn 1.40%, Nb 0.036%, V 0.046%, Al 0.025%, Ti0.017%, S 0.0040%, P 0.012%, As 0.006%, [O] 0.0015%, [N] 0.0075%, [H]0.00007%, the rest is Fe.

[0037] The carbon equivalent CEV of the obtained steel was 0.42%.

[0038] Ring rolling specifications: 3282×2970×100 After normalizing at 910°C, the mechanical properties obtained are as follows:

[0039] Tensile strength R m =525MPa, yield strength R e1 =335MPa, Elongation A 5 =28%, reduction of area Z=76%, -50°C V-notch impact energy AKv: 149J, 146J, 176J.

[0040] All the other implementations are as in Example 1.

Embodiment 3

[0042] C 0.14%, Si 0.35%, Mn 1.35%, Nb 0.037%, V 0.050%, Al 0.024%, Ti0.018%, S 0.0030%, P 0.011%, As 0.007%, [O] 0.0017%, [N] 0.0086%, [H]0.00006%, the rest is Fe.

[0043] The carbon equivalent CEV of the obtained steel was 0.43%.

[0044] Ring rolling specifications: 4000×3582×140 After normalizing at 910°C, the mechanical properties obtained are as follows:

[0045] Tensile strength R m =500MPa, yield strength R e1 =330MPa, Elongation A 5 =35%, reduction of area Z=79%, -50°C V-notch impact energy AKv: 146J, 116J, 148J.

[0046] All the other implementations are as in Example 1.

[0047] The tensile strength, yield strength, elongation and other data in the above Examples 1-3 are the actual data of the flange products made by the relevant wind power flange manufacturers using the steel for wind power flanges developed by Huaigang.

Technical field:

[0001] The invention relates to alloy steel in the iron and steel industry, in particular to the design of steel types for wind power flanges with low temperature resistance, high welding performance and high strength. Background technique:

[0002] At present, the international community is increasingly aware of the seriousness of environmental pollution and global warming. The "Kyoto Protocol" has formulated emission reduction plans and schedules. Countries have taken measures to try to curb the deterioration of environmental problems, one of which is to support the development of clean new energy.

[0003] With the rapid development of the wind power industry, the demand for steel for wind power has also increased significantly. In 2006, my country produced 100,000 tons of steel for wind power, an increase of 42.9% compared to 2005; in 2007, my country produced 150,000 tons of steel for wind power, an increase of 50% compared with 2006; In 2007, it incre...

Examples

Embodiment 1

[0028] Prepared by the following production process:

[0029] After smelting in a conventional converter or electric furnace, it is refined in a refining device, and barium microalloying and final deoxidation are performed in the later stage of refining. After the refining composition is adjusted, RH / VD is used for degassing and inclusion removal, and RH / VD can also be used for degassing and inclusion removal before LF refining. The invention can significantly improve the cleanliness of the steel through the RH / VD process, thereby significantly improving the strength and toughness of the steel and increasing the fatigue life of the material.

[0030] The chemical composition of the resulting steel:

[0031] C 0.17%, Si 0.32%, Mn 1.38%, Nb 0.039%, V 0.048%, Al 0.022%, Ti 0.015%, S 0.0030%, P 0.010%, As 0.008%, [O] 0.0016%, [ N] 0.0090%, [H] 0.00008%, the rest is Fe.

[0032] The carbon equivalent CEV of the obtained steel was 0.41%.

[0033] Ring rolling specifications: 420...

Embodiment 2

[0036] C 0.15%, Si 0.29%, Mn 1.40%, Nb 0.036%, V 0.046%, Al 0.025%, Ti0.017%, S 0.0040%, P 0.012%, As 0.006%, [O] 0.0015%, [N] 0.0075%, [H]0.00007%, the rest is Fe.

[0037] The carbon equivalent CEV of the obtained steel was 0.42%.

[0038] Ring rolling specifications: 3282×2970×100 After normalizing at 910°C, the mechanical properties obtained are as follows:

[0039] Tensile strength R m =525MPa, yield strength R e1 =335MPa, Elongation A 5 =28%, reduction of area Z=76%, -50°C V-notch impact energy AKv: 149J, 146J, 176J.

[0040] All the other implementations are as in Example 1.

Embodiment 3

[0042] C 0.14%, Si 0.35%, Mn 1.35%, Nb 0.037%, V 0.050%, Al 0.024%, Ti0.018%, S 0.0030%, P 0.011%, As 0.007%, [O] 0.0017%, [N] 0.0086%, [H]0.00006%, the rest is Fe.

[0043] The carbon equivalent CEV of the obtained steel was 0.43%.

[0044] Ring rolling specifications: 4000×3582×140 After normalizing at 910°C, the mechanical properties obtained are as follows:

[0045] Tensile strength R m =500MPa, yield strength R e1 =330MPa, Elongation A 5 =35%, reduction of area Z=79%, -50°C V-notch impact energy AKv: 146J, 116J, 148J.

[0046] All the other implementations are as in Example 1.

[0047] The tensile strength, yield strength, elongation and other data in the above Examples 1-3 are the actual data of the flange products made by the relevant wind power flange manufacturers using the steel for wind power flanges developed by Huaigang.