学术论文

      新型微合金化C--Mn--Al高强度钢的热变形行为

      Hot deformation behavior of a new microalloyed C-Mn-Al high strength steel

      摘要:
      通过Gleeble-1500热模拟单轴压缩试验,研究了一种含1.79% Al (质量分数)的以Al替代Si微合金化高强度钢在温度为900~1100℃、应变速率为0.01~30 s-1条件下的热变形行为.建立了考虑应变量对材料常数影响的双曲正弦本构方程,利用建立的本构方程预测的应力-应变曲线与实验值吻合良好,表明建立的本构方程可以对实验钢的流变应力给出相对准确的预测.建立了实验钢的加工图,根据加工图分析确定了实验钢的动态再结晶区为1000~1100℃和0.01~1 s-1.组织观察表明在动态再结晶区实验钢发生了动态再结晶,而失稳区对应的组织出现了变形集中带或“项链”组织.最后将建立的本构方程和加工图联合运用,为更全面地研究实验钢在不同变形条件下的热变形行为提供了方法.
      Abstract:
      The compressive deformation behavior of a new microalloyed high-strength steel containing 1.79% Al was investigated at temperatures from 900 to 1100℃ and strain rates from 0.01 to 30 s-1 on a Gleeble-1500 thermo-simulation machine. A hyperbolic sine equation with strain-dependent constants was developed for the steel. The predicted flow stress curves by the constitutive equation well agreed with experimental results, indicating that the constitutive equation can give a relatively accurate estimate of flow stress for the steel. According to processing map analysis, the dynamic recrystallization zone of the steel was determined as 1000 to 1100℃ and 0.01 to 1 s-1 . Microstructure observation showed that dynamic recrystallization occurred in this dynamic recrystallization zone, and in the instability zone, flow localization and necklace structure was observed. Finally, a combination of the constitutive equation and pro-cessing map provided a method for comprehensively investigating the hot deformation behavior of the steel under different conditions.
      作者: 魏海莲 [1] 刘国权 [2] 肖翔 [1] 赵海涛 [1] 丁航 [1] 康人木 [3]
      Author: WEI Hai-lian [1] LIU Guo-quan [2] XIAO Xiang [1] ZHAO Hai-tao [1] DING Hang [1] KANG Ren-mu [3]
      作者单位: 北京科技大学材料科学与工程学院,北京,100083 北京科技大学材料科学与工程学院,北京100083; 北京科技大学新金属材料国家重点实验室,北京100083 北京科技大学材料科学与工程学院,北京100083; 四川省川威集团有限公司,成都610100
      刊 名: 北京科技大学学报 ISTICEIPKU
      年,卷(期): 2014, (1)
      分类号: TG142.33
      机标分类号: TG1 TG3
      在线出版日期: 2014年2月16日
      基金项目: 国家自然科学基金资助项目,国家高技术研究发展计划资助项目