The recent rapid developments in the automobile industry have demanded the extensive use of gaivannealed （GA） steel sheets.In particular,the development of lightweight automobiles is putting increasingly higher requ...The recent rapid developments in the automobile industry have demanded the extensive use of gaivannealed （GA） steel sheets.In particular,the development of lightweight automobiles is putting increasingly higher requirements on the strength of GA steel sheets.The galvanneal furnace,which is used for processing galvannealed steel sheets,is typically composed of the induction heating section,holding section and fog cooling section.This paper described the structural characteristics of each component of the galvanneal furnace,and analyzed temperature control methods of the galvanneal furnace that are important for the successful production of high-strength GA steel sheets for automotive applications.展开更多
A new processing method for producing hot dip galvanized steel is designed and tested, in which pickling is skipped. Hot-rolled low carbon steel sheets are roiled with oxide scale in an experimental mill at room tempe...A new processing method for producing hot dip galvanized steel is designed and tested, in which pickling is skipped. Hot-rolled low carbon steel sheets are roiled with oxide scale in an experimental mill at room temperature, prior to annealing under a 20% hydrogen reducing atmosphere and galvanizing on a hot-dip galvanizing simulator. Micro-cracks formed in the oxide scale during cold rolling roughen the steel surface and enlarge the specific surface. Through-thickness cracks provide transport channels for hydrogen, and hence the reduction of oxide scale is en- hanced. When the sheet is dipped in the zinc bath, cracks are submerged by liquated zinc and the defects are not dis- tinct after hot-dip galvanizing. The overlay coating occludes with rough surface of the sheet, whereby a superior coat- ing adherence is realized.展开更多
文摘The recent rapid developments in the automobile industry have demanded the extensive use of gaivannealed （GA） steel sheets.In particular,the development of lightweight automobiles is putting increasingly higher requirements on the strength of GA steel sheets.The galvanneal furnace,which is used for processing galvannealed steel sheets,is typically composed of the induction heating section,holding section and fog cooling section.This paper described the structural characteristics of each component of the galvanneal furnace,and analyzed temperature control methods of the galvanneal furnace that are important for the successful production of high-strength GA steel sheets for automotive applications.
基金Item Sponsored by National Science and Technology Pillar Program of China(2011BAE13B04)
文摘A new processing method for producing hot dip galvanized steel is designed and tested, in which pickling is skipped. Hot-rolled low carbon steel sheets are roiled with oxide scale in an experimental mill at room temperature, prior to annealing under a 20% hydrogen reducing atmosphere and galvanizing on a hot-dip galvanizing simulator. Micro-cracks formed in the oxide scale during cold rolling roughen the steel surface and enlarge the specific surface. Through-thickness cracks provide transport channels for hydrogen, and hence the reduction of oxide scale is en- hanced. When the sheet is dipped in the zinc bath, cracks are submerged by liquated zinc and the defects are not dis- tinct after hot-dip galvanizing. The overlay coating occludes with rough surface of the sheet, whereby a superior coat- ing adherence is realized.
