Secondary cooling method for reducing transverse cracks of corners of microalloy sheet billet

A secondary cooling and micro-alloy steel technology, applied in the field of continuous casting secondary cooling, can solve the problems of high cooling intensity, low billet temperature, and reduced plasticity, achieve high cooling speed, uniform precipitates, and improve high-temperature mechanical properties Effect

Inactive Publication Date: 2013-01-09
WISDRI ENG & RES INC LTD
View PDF6 Cites 41 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the cooling intensity in the vertical section is too high, and the temperature of the slab is too low, and when the slab passes through the bending section and the straightening section, cracks will occur due to the decrease in plasticity

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

example 1

[0029] The casting steel type is boron-containing steel 45B, the cross-sectional size is 1600mm×200mm, and the casting speed is 1.1m / min. The secondary cooling method of the present invention is adopted: after the billet exits the mold, the temperature of the mold exit is 1000°C. Adjust the water volume of the wide side to 362L / min, the water volume of the narrow side to 72L / min, and the cooling time to 80s, so that the casting slab is cooled rapidly at a cooling rate of 4°C / s in the vertical section of the casting machine, and the cooling temperature of the casting slab reaches 680°C ;Subsequently reduce the amount of cooling water for the slab, use a water meter with a specific water volume of 0.7L / kg to pour, use the latent heat of solidification of the slab to warm the slab at a speed of 2°C / s, and reach 880°C when the slab exits the vertical section Above, the final slab enters the subsequent secondary cooling zone in the slow cooling mode (the specific water volume is 0.8...

example 2

[0032]The cast steel type is vanadium-containing steel 15MnV, the cross-sectional size is 1800mm×220mm, and the casting speed is 0.9m / min. The secondary cooling method of the present invention is adopted: after the billet exits the mold, the temperature of the mold exit is 1050°C. Adjust the water volume of the wide side to 380L / min, the water volume of the narrow side to 80L / min, and the cooling time to 74s, so that the casting slab is cooled rapidly at a cooling rate of 5°C / s in the vertical section of the casting machine, and the cooling temperature of the casting slab reaches 680°C . Then the slab reduces the amount of cooling water for the slab, pours with a water meter with a specific water volume of 0.7L / kg, and uses the latent heat of solidification of the slab to return the temperature of the slab. The temperature recovery speed is 3°C / s. When the slab exits the vertical section, it reaches above 900°C , the final slab enters the subsequent secondary cooling zone in s...

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

No PUM Login to view more

Abstract

The invention relates to a secondary cooling method for reducing transverse cracks of corners of a microalloy sheet billet, which is characterized in that the cooling temperature of a casting blank is facilitated to reach a temperature for starting the transformation from gamma to alpha by controlling the secondary cooling speed at an earlier stage when the casting blank passes through a vertical section after being delivered out of a crystallizer; at the later stage, the cooling water quantity of the casting blank is reduced, potential heat produced by the solidification of the casting piece is used for reheating the casting piece, and the reheating temperature is controlled to make the casting blank reach more than an austenite phase changing temperature when the casting piece is delivered out of the vertical section; the entire process is under the transformation of gamma to alpha to gamma, so that crystal grains of a final transformation product are smaller; and after the casting blank leaves the vertical section, the casting blank enters the subsequent secondary cooling area in a slowly cooling mode. By optimizing the continuous-casting billet cooling mode, the crystal grains are refined, and second-phase particles in the steel are controlled, so that the high-temperature mechanical property of the casting blank can be improved, simpleness in operation is realized, and the transverse cranks on the surface of the casting blank can be effectively reduced.

Description

technical field [0001] The invention relates to a continuous casting secondary cooling method, which can effectively control the occurrence of transverse cracks at the corners of the microalloy steel slab surface, and belongs to the technical field of continuous casting. Background technique [0002] Adding microalloying elements to steel, such as vanadium, titanium, niobium, etc., can produce solid solution, segregation, and precipitation in the matrix, and improve the strength and toughness of the steel through grain refinement, precipitation strengthening, and recrystallization control. Widely used in various steel products, microalloying can also affect the microstructure of steel through the precipitation of second phases. However, if the control is not good, a large number of carbonitrides of AlN, Nb, Ti, and V will precipitate at the grain boundaries, which will reduce the plasticity of the steel and easily generate surface transverse cracks. [0003] Transverse crac...

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 Applications(China)
IPC IPC(8): B22D11/22
Inventor 幸伟马春武徐永斌徐海伦陈洪智邵远敬叶理德袁德玉
Owner WISDRI ENG & RES INC LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap