Nb-V微合金钢凝固过程的热塑性
Hot ductility of Nb-V containing microalloyed steel during solidification
孙彦辉 1赵勇 1曾亚南 2宋方圆1
作者信息
- 1. 北京科技大学钢铁共性技术协同创新中心,北京100083
- 2. 华北理工大学冶金与能源学院,河北唐山063009
- 折叠
摘要
通过理论计算和热模拟试验对Nb-V微合金钢的热塑性进行了研究,并考察了微观偏析和析出物粒子对热塑性的影响.结果表明,S、P和0元素偏析主要发生在糊状区(固液两相区),同时树枝晶间Fe(S,0)和(Fe,Mn,Si,Al)(S,0)类夹杂物的形成导致了热塑性恶化.在1000 ～975℃区间,NbN粒子直径由20 nm减小到10 nm,粒子数量由23个/μm2上升到45个/μm2,断面收缩率迅速由82.36％下降到69.61％;在900～850℃区间,断面收缩率缓慢下降并伴随有铁素体膜逐渐变厚.温度小于975℃、高临界应力下容易发生晶间断裂,从而产生裂纹源.
Abstract
Hot ductility of Nb-V-containing steel was studied by theoretical calculation and thermal simulation experiments,and effect of microsegregation and precipitates on hot ductility was studied.The results show that segregation degrees of elements S,P and 0 are greater in mushy zone,while,the hot ductility is deteriorated by inclusions of Fe (S,O) and (Fe,Mn,Si,Al) (S,O) in the interdendritic regions.In the temperature range from 1000 ℃ to 975 ℃,reduction of area rapidly decreases from 82.36％ to 69.61％,the diameters decrease from 20 to 10 nm and quantity of particles increase from 23 to 45 inds/μm2,respectively.In the temperature range of 900 ℃ to 850 ℃,the reduction of area reduces slowly with ferrite films thickening gradually.Intergranular fracture is easy to occur with higher critical stress below 975 ℃.
关键词
溶质偏析/脆性区/低应变速率/析出物/临界应力Key words
solute segregation/brittle zone/low strain rate/precipitation/critical stress引用本文复制引用
出版年
2016
NETL
NSTL
维普
万方数据