Luhan Hao Namin Xiao Chengwu Zheng Dianzhong Li
材料科学技术（英）
The microstructures and mechanical properties of deformation induced ferrite (DIF) in the low carbon steel Q235 under different deformation temperatures have been investigated systematically. Through deformation induced ferrite transformation (DIFT), ferrite grain can be refined to 3 μm and accounts for above 85% of the overall fraction. Yield strength of DIF (>500 MPa) is increased by up to 100% compared with the conventional low carbon steel. Comparison of microstructure and mechanical properties in the Q235 steel with DIF and tempered DIF microstructure illustrates that the strengthening mechanism of DIF microstructure is the com- bination of grain boundary strengthening and carbon supersaturated strengthening. Electron back-scattered diffraction (EBSD) analysis and high magnification scanning electron microscopy (SEM) observation denote that high-angle grain boundary among ultrafine ferrite grain and the transformation product of retain austenite membrane along ferrite boundaries are responsible for the stability of ferrite grain size during tempering
process. Transmission electron microscopy (TEM) analysis demonstrates that the transformation product of retained austenite membrane between ferrite grain boundaries is cementite.
关键词:
Low carbon steel
,
DIFT
,
Grain size
,
Mechanical properties
,
Temper resistance
Lin HU
,
Xiaodong HU
,
Peng GAO
,
Hongyang ZHAO
,
Dong-Ying Ju
材料科学技术（英）
Based on the discussing of the mechanisms of grain refinement strengthening and deformation induced transformation, the characteristics of controlled rolling and controlled cooling for high-speed wire were analyzed. Aiming at the problems of wire mill in Anshan Iron & Steel Co., turbulent cooler and spray cooler on the Stelmor conveyor were developed. Super-steels had been developed for Q235 steel through unrecrystallized austenite region rolling. The constitution and properties of the wire on the coil overlap zone were also improved. This proved the possibility that super-steels can be developed in high-speed wire mill.
关键词:
Super-steel
,
null
,
null
,
null
刘东升
,
李冉
,
陈少慧
钢铁
通过系统的实验室研究、中试工场热轧试验和工业生产热轧试验,成功实现了热连轧细晶粒系列C-Mn钢的工业化生产。利用变形诱导铁素体相变（DIFT）机制和变形后快速冷却工艺,在w（[Mn]）为0.2%～0.7%的低碳（w（[C]）为0.13%～0.17%）钢中获得了细晶粒多边形铁素体（PF）＋珠光体（P）＋贝氏体（B）组织。使用奥氏体未再结晶区终轧和快速冷却工艺路线在高锰钢（w（[C]）为0.13%～0.17%,w（[Mn]）为1.5%）中得到了PF＋B组织。在1450mm热带钢连轧生产线上,批量生产出厚度4.0～5.5mm细晶粒热轧板卷。
关键词:
细晶粒钢
,
变形诱导铁素体相变
,
快速冷却
,
卷取
