HSLA steels constitute one of the main types of steels produced worldwide by Thin Slab Direct Rolling technologies (TSDR).Among microalloying elements,the most widely used are V,Nb and Ti.These elements play different...HSLA steels constitute one of the main types of steels produced worldwide by Thin Slab Direct Rolling technologies (TSDR).Among microalloying elements,the most widely used are V,Nb and Ti.These elements play different roles during the austenite evolution in TSDR.Regarding austenite conditioning before transformation,the limitations in the total reduction that can be applied in TSDR technologies need to be considered when composition/process parameters are selected.In this context,whereas an important number of studies have been focused on Nb microalloyed grades,a less systematic analysis has been performed concerning the role of vanadium on austenite conditioning.This paper analyzes these singularities taking into account different process parameter conditions,such as total reduction and initial rolling temperature.展开更多
Large quantity of fine Ti（C,N） particles, 15-30 nm in size, were observed in low carbon hot strips added to a small amount of Ti and produced by CSP process. The results showed that the precipitation of Ti（C,N） mo...Large quantity of fine Ti（C,N） particles, 15-30 nm in size, were observed in low carbon hot strips added to a small amount of Ti and produced by CSP process. The results showed that the precipitation of Ti（C,N） mostly took place during soaking and hot rolling, which is significantly different from that in the conventional production. These fine Ti carbonitride particles could be very effective on the austenite grain refinement by hindering grain growth of recrystallized austenite. Their precipitation behavior was discussed and compared with that of the steels produced in the conventional production.展开更多
By careful design of rolling schedule,ultra-fine （～2μm） ferrite grains in a low carbon high niobium （0.09wt%Nb） microalloying steel with average austenite grain sizes above 800 μm can be achieved in the simulat...By careful design of rolling schedule,ultra-fine （～2μm） ferrite grains in a low carbon high niobium （0.09wt%Nb） microalloying steel with average austenite grain sizes above 800 μm can be achieved in the simulated thin slab direct rolling process. The 5-pass deformation was divided into two stages： the refinement of austenite through complete recrystallization and the refinement of ferrite through dynamic strain-induced transformation. The effects of Nb in solution and strain-induced NbCN precipitates on the ferrite transformation were also extensively discussed.展开更多
文摘HSLA steels constitute one of the main types of steels produced worldwide by Thin Slab Direct Rolling technologies (TSDR).Among microalloying elements,the most widely used are V,Nb and Ti.These elements play different roles during the austenite evolution in TSDR.Regarding austenite conditioning before transformation,the limitations in the total reduction that can be applied in TSDR technologies need to be considered when composition/process parameters are selected.In this context,whereas an important number of studies have been focused on Nb microalloyed grades,a less systematic analysis has been performed concerning the role of vanadium on austenite conditioning.This paper analyzes these singularities taking into account different process parameter conditions,such as total reduction and initial rolling temperature.
基金This work was financially supported by the National Natural Science Foundation of China (No.50371009)
文摘Large quantity of fine Ti（C,N） particles, 15-30 nm in size, were observed in low carbon hot strips added to a small amount of Ti and produced by CSP process. The results showed that the precipitation of Ti（C,N） mostly took place during soaking and hot rolling, which is significantly different from that in the conventional production. These fine Ti carbonitride particles could be very effective on the austenite grain refinement by hindering grain growth of recrystallized austenite. Their precipitation behavior was discussed and compared with that of the steels produced in the conventional production.
基金the Major State Basic Research and Development Program of China (No2004CB619102)
文摘By careful design of rolling schedule,ultra-fine （～2μm） ferrite grains in a low carbon high niobium （0.09wt%Nb） microalloying steel with average austenite grain sizes above 800 μm can be achieved in the simulated thin slab direct rolling process. The 5-pass deformation was divided into two stages： the refinement of austenite through complete recrystallization and the refinement of ferrite through dynamic strain-induced transformation. The effects of Nb in solution and strain-induced NbCN precipitates on the ferrite transformation were also extensively discussed.
