Preparation method of low-carbon high-strength round steel

Abstract

The invention discloses a preparation method of low-carbon high-strength round steel. The low-carbon high-strength round steel is prepared through the steps of heating, rough rolling, 600-ton shearing, medium rolling, rack marshalling, pre-finish rolling, KOCKS finish rolling, 3 # / 4 # / 5 # water tank rapid cooling, stepping type cooling bed cooling, wind-shielding stack cooling, straightening, flaw detection, chamfering, packaging, weighing and warehousing. Through process controlled rolling, the grain size of a rolled product is ensured, rapid cooling is conducted through a 3 # / 4 # / 5 # water tank after KOCKS finish rolling, and the ferrite precipitation proportion after rolling is reduced, so that the purpose of improving the strength is achieved, the low-carbon high-strength round steel is obtained, and the use requirement of a new energy automobile energy accumulator is met.

Description

Technical Field

[0001] The invention relates to the field of steel, and in particular to a method for preparing low-carbon high-strength round steel. Background Art

[0002] New energy vehicles refer to vehicles that use unconventional vehicle fuels as their power source (or use conventional vehicle fuels and new vehicle power devices), and integrate advanced technologies in vehicle power control and drive to form vehicles with advanced technical principles, new technologies, and new structures. New energy vehicles include pure electric vehicles, extended-range electric vehicles, hybrid vehicles, fuel cell electric vehicles, etc.

[0003] Energy storage devices are an important part of new energy vehicles. They can store energy efficiently and release energy when needed. However, the energy storage devices of new energy vehicles currently use steel materials commonly used in the market, which have the problem of low strength. Therefore, it is necessary to develop new steel materials that meet the requirements of energy storage devices for new energy vehicles. Summary of the invention

[0004] Purpose of the invention: In view of the shortcomings and defects of the prior art, the present invention provides a method for preparing low-carbon and high-strength round steel. Through process controlled rolling, the grain size of the rolled product is ensured. After KOCKS finishing rolling, the 3# / 4# / 5# water tank is quickly cooled to reduce the proportion of ferrite precipitation after rolling, so as to achieve the purpose of improving strength and obtain low-carbon and high-strength round steel, which meets the use requirements of energy storage devices for new energy vehicles.

[0005] Technical solution: A method for preparing low-carbon high-strength round steel of the present invention is characterized by: preparing by the method of heating → rough rolling → 600-ton shear → intermediate rolling → marshaling stand → pre-finishing rolling → KOCKS finishing rolling → 3# / 4# / 5# water tank fast cooling → walking-type cooling bed cooling → windproof pile cooling → straightening → flaw detection → chamfering → packaging → weighing → warehousing.

[0006] Wherein, the temperature before the intermediate rolling process is controlled at 980°C-1020°C.

[0007] Wherein, the temperature before the KOCKS finishing rolling process is controlled at 810°C-860°C.

[0008] Among them, the 3# / 4# / 5# water tank is quickly cooled after the KOCKS finishing rolling process to reduce the proportion of ferrite precipitation after rolling.

[0009] Wherein, the cooling temperature in the 3# / 4# / 5# water tank quick cooling process is 480°C-590°C.

[0010] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: the present invention ensures the grain size of the rolled product through process controlled rolling (temperature control of 980℃-1020℃ before intermediate rolling, temperature control of 810℃-860℃ before KOCKS finishing rolling), and reduces the proportion of ferrite precipitation after rolling through rapid cooling of 3# / 4# / 5# water tanks after KOCKS finishing rolling, so as to achieve the purpose of improving strength, and obtain low-carbon and high-strength round steel, which meets the use requirements of energy storage devices for new energy vehicles. DETAILED DESCRIPTION

[0011] The technical solution of the present invention is further described below in conjunction with specific implementation methods.

[0012] The preparation method of the low-carbon high-strength round steel of the present invention adopts the method of heating → rough rolling → 600-ton shear → intermediate rolling → marshaling stand → pre-finishing rolling → KOCKS finishing rolling → 3# / 4# / 5# water tank fast cooling → walking type cooling bed cooling → windproof pile cooling → straightening → flaw detection → chamfering → packaging → weighing → warehousing for preparation.

[0013] Among them, the temperature control before the intermediate rolling process is 980℃-1020℃. The temperature control before the KOCKS finishing rolling process is 810℃-860℃. After the KOCKS finishing rolling process, the 3# / 4# / 5# water tank is used for rapid cooling to reduce the proportion of ferrite precipitation after rolling. The cooling temperature in the 3# / 4# / 5# water tank rapid cooling process is 480℃-590℃.

[0014] The present invention ensures the grain size of the rolled product through process controlled rolling (temperature control of 980°C-1020°C before intermediate rolling and temperature control of 810°C-860°C before KOCKS finishing rolling), and reduces the proportion of ferrite precipitation after rolling through rapid cooling in 3# / 4# / 5# water tanks after KOCKS finishing rolling, so as to achieve the purpose of improving strength.

[0015] Example:

[0016] The product grade of this embodiment is AA, and the product specification is ∮88mm.

[0017] The chemical composition of the product includes the following components in mass percentage: C: 0.09%, Si: 0.24%, Mn: 1.01%.

[0018] The preparation process route adopts the method of the present invention.

[0019] Heating parameters:

[0020]

[0021] Controlled rolling and controlled cooling parameters:

[0022]

[0023] After testing, the main mechanical properties are as follows:

[0024]

Claims

1. A method for preparing low-carbon high-strength round steel, characterized in that: The preparation is carried out by the method of heating → rough rolling → 600-ton shear → intermediate rolling → marshalling stand → pre-finishing rolling → KOCKS finishing rolling → 3# / 4# / 5# water tank quick cooling → walking type cooling bed cooling → windproof pile cooling → straightening → flaw detection → chamfering → packaging → weighing → warehousing.

2. The method for preparing low-carbon high-strength round steel according to claim 1, characterized in that: The temperature before the intermediate rolling process is controlled at 980°C-1020°C.

3. The method for preparing low-carbon high-strength round steel according to claim 1, characterized in that: The temperature before the KOCKS finishing rolling process is controlled at 810°C-860°C.

4. The method for preparing low-carbon high-strength round steel according to claim 1, characterized in that: After the KOCKS finishing rolling process, the 3# / 4# / 5# water tank is used for rapid cooling to reduce the proportion of ferrite precipitation after rolling.

5. The method for preparing low-carbon high-strength round steel according to claim 4, characterized in that: The cooling temperature in the 3# / 4# / 5# water tank quick cooling process is 480°C-590°C.

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