摘要
利用Hopkinson压杆技术对X70管线钢进行了冲击压缩实验,研究了在高应变率变形过程中 钢的组织演变和动态应力-应变行为．结果表明:经过适当热处理后X70管线钢具有以针状铁素体为主 的显微组织．在103s-1应变率条件下,该钢发生了明显的应变强化与应变率强化,且最大应变也随应变率 提高而增加;在铁素体板条内形成的大量位错胞亚晶结构和铁素体组织的显著细化,是该钢高应变率增强增 塑的主要机制．
The impact compression experiments for X70 pipeline steel after heat treatment at 860 for 30 min followed by oil cooling and 180 ℃ for 1 h followed by air cooling, were carried out using the Hopkinson pressure bar. The structural evolution occurring during plastic deformation under high strain rate and dynamic stress-strain behavior were investigated. The results show that X70 pipeline steel after the heat treatment has the acicular ferrite dominated microstructure. The phenomenon of work-hardening and strain rate strengthening for the steel are observed at the strain rates of 10^3s^-1, and maximum strain also raises with the increasing of strain rate. A lot of dislocation cells form in the ferrite laths and its microstructure is fined remarkably, which leads to the increase in both the strength and the plasticity under high strain rate for the steel.
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
2005年第6期561-566,共6页
Chinese Journal of Materials Research
基金
国家重点基础研究发展计划G1999065003资助项目~~
关键词
金属材料
针状铁索体
应变率-应力
应变行为
微观结构
metallic materials, acicular ferrite, strain rate, stress-strain behavior, microstructure
