摘要
研究了薄板坯连铸连轧流程生产的低碳Al镇静钢普遍存在的组织偏细,强度偏高的问题。研究结果表明,薄板坯连铸出坯后已有AlN沉淀析出,经均热1 423 K×30 min后仍有约30×10-6AlN未溶解。这些AlN微细沉淀对抑制奥氏体再结晶晶粒长大、抑制相变铁素体晶粒长大起到一定作用,使钢带组织细化;另外,薄板坯连铸连轧流程轧后冷却段长度偏短,冷却强度偏高也是造成组织细化,强度偏高的主要原因。
Compared with low carbon Al-killed strip produced by conventional cold charge rolling process, the strip produced by TSCR has refiner microstructure and higher yield strength. This is beneficial to production of high strength strip, but makes cold rolling a little bit difficult. In order to study this phenomenon, the behavior of Al during slab cooling and rolling was studied. It was found that some AlN are precipitated in low carbon Al-killed steel before entry the roller hearth furnace. After holding 30 min at 1 423 K, there are still 30×10^-6 AlN in the slab, which are responsible for restraining the coarsening of recrystallized austenite and transformed ferrite. As a result, a refiner microstructure could be archived in TSCR. On other hand, the shorter cooling table compared with that of conventional rolling mill accelerates the cooling rate of TSCR, providing a beneficial condition for refining microstructure.
出处
《钢铁》
CAS
CSCD
北大核心
2005年第8期65-69,共5页
Iron and Steel
