Ultra Fast Cooling and Its Effect on the Mechanical Properties of Steel

2013 ◽  
Vol 136 (3) ◽  
Author(s):  
Soumya S. Mohapatra ◽  
Satya V. Ravikumar ◽  
Ravi Ranjan ◽  
Surjya K. Pal ◽  
Shiv Brat Singh ◽  
...  
Keyword(s):  
Cooling Rate ◽  
Steel Plate ◽  
Cooling System ◽  
Spray Cooling ◽  
High Mass ◽  
Ultra Fast Cooling ◽  
Thick Steel ◽  
Fast Cooling ◽  
Ultrafast Cooling ◽  
Plate Distance

The objective of this work is to study about the ultrafast cooling of a hot static 6 mm thick steel plate (AISI-1020) by air assisted spray cooling. The study covers the effect of air flow rate and the water impingement density on the cooling rate. The initial temperature of the plate, before the cooling starts, is kept at 900 °C. The spray was produced from a full cone high mass flux and low turn down ratio air atomizer at a fixed nozzle to plate distance. The cooling rate shows that low turn down ratio air atomized spray can generate ultra fast cooling (UFC) rate for a 6 mm thick steel plate. After cooling, the tensile strength and hardness of the cooled steel plate were examined. The surface heat flux and surface temperature calculations have been performed by using INTEMP software. The result of this study could be applied in designing of fast cooling system especially for the run-out table cooling.

Ultra Fast Cooling of a Hot Steel Plate by Using High Mass Flux Air Atomized Spray

2012 ◽  
Vol 84 (3) ◽  
pp. 229-236 ◽  
Author(s):  
Soumya S. Mohapatra ◽  
Satya V. Ravikumar ◽  
Surjya K. Pal ◽  
Sudipto Chakraborty
Keyword(s):  
Mass Flux ◽  
Steel Plate ◽  
High Mass ◽  
Ultra Fast Cooling ◽  
Fast Cooling

Experimental Investigation of Effect of a Surfactant to Increase Cooling of Hot Steel Plates by a Water Jet

2013 ◽  
Vol 135 (3) ◽  
Author(s):  
Soumya S. Mohapatra ◽  
Satya V. Ravikumar ◽  
Ankur Verma ◽  
Surjya K. Pal ◽  
Sudipto Chakraborty
Keyword(s):  
Heat Flux ◽  
Cooling Rate ◽  
Surface Heat Flux ◽  
Surfactant Concentration ◽  
Steel Plate ◽  
Pure Water ◽  
Water Jet ◽  
Surface Heat ◽  
Added Water ◽  
Ultrafast Cooling

The requirement for high tensile strength steel has placed greater emphasis on the cooling methods used in the cooling of a hot steel plate. The purpose of this research is to study the effect of surfactant concentration in water jet cooling, and its applicability in the study of ultrafast cooling (UFC) of a hot steel plate. The initial temperature of the plate, before the cooling starts, is kept at 900 °C which is usually observed as the “finish rolling temperature (FRT)” in the hot strip mill of a steel plant. The current heat transfer analysis shows that surfactant added water jet produces higher heat flux than the pure water jet due to the higher forced convection cooling area. Dissolved surfactant increases the transition boiling heat flux, nucleate boiling heat flux and critical heat flux. At a concentration of 600 ppm, the maximum surface heat flux has been observed and further increase in surfactant concentration decreases the surface heat flux. The surface heat flux and the cooling rate show an increasing trend with the increasing water flow rate at a constant surfactant concentration. The achieved cooling rate in case of surfactant added water is almost twice that of jet with pure water, resulting in ultrafast cooling. By assuming the impinging surface consists of three different constant heat flux regions, the surface heat flux and the surface temperatures have been calculated by using intemp software.

An Ultra Fast Cooling Method for Cell Vitrification Cryopreservation Utilizing Thin Film Evaporation

2016 ◽  
Author(s):  
Fengmin Su ◽  
Nannan Zhao ◽  
Yangbo Deng ◽  
Bohan Tian ◽  
Chunfeng Mu ◽  
...  
Keyword(s):  
Thin Film ◽  
Cooling Rate ◽  
Experimental Results ◽  
Thin Film Evaporation ◽  
Ultra Fast Cooling ◽  
Film Evaporation ◽  
Cooling Method ◽  
A Cell ◽  
Fast Cooling ◽  
Cryoprotective Solution

Ultra-fast cooling is the key to successful cell vitrification cryopreservation of lower concentration cryoprotective solution. This research develops a cell cryopreservation methodology which utilizes thin film evaporation and achieves vitrification of relatively low concentration cryoprotectant with an ultra-fast cooling rate. Experimental results show that the average cooling rate of dimenthylsulphoxide cryoprotective solution reaches 150,000°C/min in a temperature range from 10°C to −180°C. The ultra-fast cooling rate can remarkably improve the vitrification tendencies of the cryoprotective solution. This methodology opens the possibility for more successful cell vitrification cryopreservation.

Research on Hot Stamping Technology of High Strength Medium and Heavy Steel Plate

2020 ◽  
Vol 837 ◽  
pp. 81-86 ◽  
Author(s):  
Ning Ma ◽  
Yu Jie Ma ◽  
Ye Xuan Wang ◽  
Jian Yi Ji ◽  
Yi Chun Ji ◽  
...  
Keyword(s):  
Cooling Rate ◽  
Temperature Difference ◽  
Production Efficiency ◽  
Steel Plate ◽  
Cooling System ◽  
Hot Stamping ◽  
High Strength ◽  
Steel Plates ◽  
Large Temperature ◽  
Forming Process

An innovative study on the high strength of U shaped steel plate was carried out. Through the two different cooling systems of hot stamping die obtained the two U shaped steel plates, founding that the cooling rate of U shaped steel plate obtained by bath water cooling system in the die was significantly higher than the steel plate obtained by cooling pipe in the die system, and had a smaller temperature difference, Which is a good solution to the problem the cooling rate of blank decreases with the thickness of blank increasing and the blank had a large temperature difference for badly uniform temperature quenching. This system is also greatly shorten the quenching time and improve the production efficiency in hot forming process.

Research and Application of Automation Controlling System for Plate Ultra Fast Cooling Process

2012 ◽  
Vol 605-607 ◽  
pp. 1836-1840
Author(s):  
Xiao Lin Chen ◽  
Bing Xing Wang ◽  
Yong Tian ◽  
Guo Yuan ◽  
Zhao Dong Wang ◽  
...  
Keyword(s):  
Control System ◽  
Automatic Control ◽  
Automatic Control System ◽  
Cooling System ◽  
Low Cost ◽  
Control Process ◽  
Control Unit ◽  
Controlled Cooling ◽  
Ultra Fast Cooling ◽  
Fast Cooling

To implement the new generation thermo mechanical control process (NG-TMCP), the automatic control system of ultra fast cooling (UFC) was developed by combined with the renovation project of controlled cooling system in one plate production line. This system was composed of basic automation subsystem and process automation subsystem. As the main control unit of the basic automatic control system, a S7400 PLC system is used to control the UFC device and to achieve the chain control between the UFC system and the mill system. While the process control system is to realize the automatical setting of the cooling schedule by the developed finite element temperature field model and the temperature homogeneity model. The industry application shows that the NG-TMCP which is based on the UFC can reduce the alloy content effectively and implement the low-cost reduction produce of high-grade products.

The Development and Application of the Hot-Rolled Plate Ultra-Fast Cooling Equipment

2010 ◽  
Vol 145 ◽  
pp. 260-267
Author(s):  
Guo Yuan ◽  
Guo Dong Wang
Keyword(s):  
Steel Plate ◽  
Rolled Plate ◽  
Rolled Steel ◽  
Cooling Process ◽  
Ultra Fast Cooling ◽  
Impingement Heat Transfer ◽  
Flow Field Characteristics ◽  
Fast Cooling ◽  
Hot Rolled ◽  
Hot Rolled Steel

The ultra-fast cooling technical is a newly developed thermal technical in recent years for the hot-rolled steel plate. The key to develop the ultra-fast cooling equipment are the design of the nozzle structure and the cooling process. The heat exchange mechanism of the jetting impingement heat transfer mode was illustrated during ultra-fast cooling process for the hot-rolled steel plate in this paper. The flow field characteristics and the cooling technological process during the plate ultra-fast cooling process were simulated. And the newly-developed ultra-fast cooling equipment for the hot-rolled plate and its application were also introduced in this paper.

Study on Ultra Fast Cooling Technology in Hot Strip Mill

2011 ◽  
Vol 418-420 ◽  
pp. 1635-1639 ◽  
Author(s):  
Liang Gui Peng ◽  
Xian Ming Zhao ◽  
Di Wu ◽  
Yang Gao ◽  
Zhong Ping Zhang ◽  
...  
Keyword(s):  
Cooling System ◽  
Value Added ◽  
Cooling Capacity ◽  
Laboratory Research ◽  
Cooling Power ◽  
Hot Strip Mill ◽  
Ultra Fast Cooling ◽  
Circular Nozzle ◽  
Hot Strip ◽  
Fast Cooling

With advanced high-strength steels and high value-added steels development, it is very important to improve the cooling capacity and cooling intensity of the run out table cooling system. The key technology is to break the vapor between hot strip and cold water and to increase the direct contact area. In order to realize the ultra fast cooling, Laboratory research such as jet nozzle type selection and diameter of nozzle decision and factory tests such as cooling capacity testing have been done. Experiment results show that circular nozzle has bigger hitting power than fan-type nozzle. However, drainage capacity caused by fan-type nozzle is better than that by circular nozzle. In addition, nozzles of different diameters have nearly the same cooling capacity despite of the very different water flow. Cooling power testing results show that cooling capacity is enhanced with pressure increasing and with speed decreasing.

Influence of Cooling Rate on the Microstructures and Properties of a Nb-Ti-Mo Steel

2012 ◽  
Vol 152-154 ◽  
pp. 14-17
Author(s):  
Hai Long Yi ◽  
Yang Xu ◽  
Zhen Yu Liu ◽  
Guo Dong Wang
Keyword(s):  
Tensile Strength ◽  
Cooling Rate ◽  
High Strength ◽  
Strengthening Mechanisms ◽  
Micro Hardness ◽  
Cooling Process ◽  
Ultra Fast Cooling ◽  
Fast Cooling ◽  
Cooling Technology ◽  
Strength And Toughness

A Nb-Ti-Mo high strength steel was selected at two different cooling rates through ultra-fast cooling process, and its microstructures and strengthening mechanisms were analyzed. The results show the size of ferrite was decreased and the amount of bainite and micro-hardness were increased with increasing of cooling rate through thermal simulation. The UFC technology can improve the yield and tensile strength 25MPa and 35MPa, respectively, compared with conventional TMCP. The microstructure of this steel is mainly ferrite and good strength and toughness are caused by the refinement of ferrite and fine precipitates. Ultra-fast cooling technology improves the strength and toughness of this steel effectively.

Sign in / Sign up

Export Citation Format

Share Document