Cold-rolled steel sheets in automotive applications require an excellent deep draw ability, which is characterized by the Lankford value (r-value). In this study, a correlation was identified between r-value and pan...Cold-rolled steel sheets in automotive applications require an excellent deep draw ability, which is characterized by the Lankford value (r-value). In this study, a correlation was identified between r-value and pancake-shaped grain flatness which is indicated as the ratio of grain diameter in the rolling direction (RD) and normal direction (ND) of sheets (dr/dn). A mathematical model ( r = e^0.345(dn^1/2-dr^1/2) ) was developed to calculate r-value by the microstructure of steel sheets hot-rolled by compact strip production (CSP). It is shown that the r-value is higher, if the microstructure of steel sheet is of pancake-shaped grains elongated in the rolling direction. The calculated r-value is confirmed to fit exactly to the measured one from the large-scale production.展开更多
As one of the most mature aluminum sheet continuous strip-casting processes,Hazelett strip-casting has been successfully industrially applied.This work introduced the key refractory materials for Hazelett strip-castin...As one of the most mature aluminum sheet continuous strip-casting processes,Hazelett strip-casting has been successfully industrially applied.This work introduced the key refractory materials for Hazelett strip-casting process,including large-scaled Al_2O_3 ceramic foam filters,wide-feed head boxes,monolithic strip-stream nozzles,and coatings on twin-belt.Besides,the localization of the refractory materials was discussed.展开更多
Since the 2050 mm hot strip mill was put into operation in 1989, Baosteel has made great achievements in increasing productivity, developing new process technologies and steel products and improving product quality. I...Since the 2050 mm hot strip mill was put into operation in 1989, Baosteel has made great achievements in increasing productivity, developing new process technologies and steel products and improving product quality. In the past 18 years from 1989 to 2007 ,Baosteel has constructed five hot strip mills with a total annual capacity of 19.8 Mt. Indices for technology standards, product categories and steel grades, product quality, both technically and economically, take the lead domestically or reached the world class level. As there are many hot strip mills that expected to be put into operation by the end of 2010 ,the overall annual capacity will exceed 30 Mt ,and the product will cover grain oriented (GO) Si steels and alloyed steels.展开更多
文摘Cold-rolled steel sheets in automotive applications require an excellent deep draw ability, which is characterized by the Lankford value (r-value). In this study, a correlation was identified between r-value and pancake-shaped grain flatness which is indicated as the ratio of grain diameter in the rolling direction (RD) and normal direction (ND) of sheets (dr/dn). A mathematical model ( r = e^0.345(dn^1/2-dr^1/2) ) was developed to calculate r-value by the microstructure of steel sheets hot-rolled by compact strip production (CSP). It is shown that the r-value is higher, if the microstructure of steel sheet is of pancake-shaped grains elongated in the rolling direction. The calculated r-value is confirmed to fit exactly to the measured one from the large-scale production.
文摘As one of the most mature aluminum sheet continuous strip-casting processes,Hazelett strip-casting has been successfully industrially applied.This work introduced the key refractory materials for Hazelett strip-casting process,including large-scaled Al_2O_3 ceramic foam filters,wide-feed head boxes,monolithic strip-stream nozzles,and coatings on twin-belt.Besides,the localization of the refractory materials was discussed.
文摘Since the 2050 mm hot strip mill was put into operation in 1989, Baosteel has made great achievements in increasing productivity, developing new process technologies and steel products and improving product quality. In the past 18 years from 1989 to 2007 ,Baosteel has constructed five hot strip mills with a total annual capacity of 19.8 Mt. Indices for technology standards, product categories and steel grades, product quality, both technically and economically, take the lead domestically or reached the world class level. As there are many hot strip mills that expected to be put into operation by the end of 2010 ,the overall annual capacity will exceed 30 Mt ,and the product will cover grain oriented (GO) Si steels and alloyed steels.