Unlock instant, AI-driven research and patent intelligence for your innovation.

Production Method for Improving Toughness of Yield Strength 345mpa Grade Thick Steel Plate

A yield strength and production method technology, applied in the field of material processing, can solve the problems of high manufacturing cost and alloy cost, complex manufacturing process, difficult management, etc., and achieve the effect of low manufacturing cost, loose process system and low alloy cost.

Active Publication Date: 2015-09-16
INNER MONGOLIA BAOTOU STEEL UNION
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, this method improves the toughness through the heat treatment process of quenching+quenching+tempering and adding expensive alloys such as Mo and Ni. The manufacturing process of the steel plate is complicated, the management is difficult, the manufacturing cycle is long, and the manufacturing cost and alloy cost are high.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034] The thickness of the slab is 250mm, the carbon content is 0.073%, the thickness of the finished steel plate is 50mm, the temperature of the slab out of the furnace is 1210°C, and the heating time is 260 minutes. The steel plate is rolled in two stages. In the first stage, the thickness of the slab is 250mm. After the continuous casting slab is released from the furnace, it is first widened and rolled. After the widened and rolled, the steel is turned to 90 degrees. Rolling is carried out at 1140°C. When the slab is warmed and rolled again, the minimum single-pass reduction rate of the steel plate is 10%. There are 7 passes in the first stage, and the first stage is rolled to 110mm. ; The starting thickness of the steel plate in the second stage is 110mm, the starting temperature of the second stage is 920°C, and the final rolling temperature is 860°C; %, 17.4%, 15.8%, 14.1%, 9.1%, the rolling speeds of the corresponding passes are 2.2m / s, 2.6m / s, 2.9m / s, 3.1m / s, 3.1m / s ...

Embodiment 2

[0037] The thickness of the slab is 250mm, the carbon content is 0.06%, the thickness of the finished steel plate is 60mm, the temperature of the slab out of the furnace is 1240°C, and the heating time is 450 minutes. The steel plate is rolled in two stages. In the first stage, the starting thickness of the slab is 250 mm. After the slab is released from the furnace, it is first widened and rolled. After the widened and rolled, the steel is turned to 90 degrees. Rolling is carried out at 1145°C. When the slab is re-rolled after the temperature is completed, the minimum single-pass reduction rate of the steel plate is 12.5%. The first stage is rolled for 6 passes, and the first stage is rolled to 112mm; The starting rolling thickness of the steel plate in the second stage is 112mm, the starting rolling temperature in the second stage is 910°C, and the finishing rolling temperature is 870°C; 15.5%, 15.9%, 13%, the corresponding rolling speeds are 3.2m / s, 3.5m / s, 3.5m / s, 4m / s res...

Embodiment 3

[0039] The thickness of the slab is 250mm, the carbon content of the steel plate is 0.08%, the thickness of the finished steel plate is 100mm, the furnace temperature of the slab is 1236°C, and the heating time is 385 minutes. The steel plate is rolled in two stages. In the first stage, the starting thickness of the slab is 250 mm. After the slab is released from the furnace, it is first widened and rolled. After the widened and rolled, the steel is turned to 90 degrees. Rolling is carried out at 1143°C. When the slab is re-rolled after the temperature is completed, the minimum single-pass reduction rate of the steel plate is 13%. The first stage is rolled for 5 passes, and the first stage is rolled to 120mm; The starting thickness of the steel plate in the second stage is 120mm, the starting temperature of the second stage is 900°C, and the final rolling temperature is 880°C; 4.3%, the rolling speeds of the corresponding passes are 2m / s and 2.2m / s respectively; the cooling sp...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
yield strengthaaaaaaaaaa
thicknessaaaaaaaaaa
thicknessaaaaaaaaaa
Login to View More

Abstract

The invention discloses a production method for improving toughness of a thick steel plate with 345MPa-level yield strength. The method comprises the steps: heating a plate blank with the thickness of 250mm for 260-450 minutes, wherein the tapping temperature of the plate blank is 1,210-1,240 DEG C; rolling the heated plate blank, wherein the rolling thickness in the first stage is the thickness (250mm) of the plate blank; the plate blank is widened for rolling until the target width of the steel plate is reached; the steel plate is turned for 90 degrees after the widened rolling is finished; rolling is performed again after the average temperature of the plate blank is reduced to be 1,140-1,145 DEG C; the reduction rate of the steel plate for single pass is more than or equal to 10 percent after the plate blank is cooled to a constant temperature for rolling again, and rolling is performed for 5-7 passes in the first stage; the rolling thickness in the second stage is 1.2-2.2 times of the thickness of a finished product steel plate, the rolling temperature is 900-920 DEG C in the second stage, the finish rolling temperature is 860-880 DEG C, the reduction rate for at least one pass is more than or equal to 12 percent, and the rolling speed is 2-4m / s for every pass; and performing laminar cooling on the rolled steel plate at the speed of 5-8 DEG C / s, wherein the final cooling temperature is 570-610 DEG C.

Description

technical field [0001] The invention relates to the field of material processing, in particular to a production method for improving the toughness of a thick steel plate with a yield strength of 345MPa. Background technique [0002] Low-alloy high-strength steel plates with a yield strength of 345MPa are widely used in various fields of the national economy. For example, the country is vigorously developing clean energy wind power. The main material of the tower rod used to support the rotation of the blades is a yield strength of 345MPa. Grade low-alloy high-strength steel plates, and account for a considerable part of thick steel plates with a thickness greater than 40mm. [0003] Due to the thicker steel plate, the compression ratio during rolling is small, and the refinement and crushing effect on austenite grains is also limited. Moreover, due to the thicker steel plate after rolling, even if laminar flow cooling is used, the actual cooling rate of the steel plate is al...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): C21D8/02
Inventor 温利军张大治刘海涛徐建东赵超戴鑫王遐亮
Owner INNER MONGOLIA BAOTOU STEEL UNION