摘要
利用分离式Hopkinson压杆装置对不同Ce含量(0%、0.2%、0.4%)的2519A铝合金进行冲击压缩试验,压缩温度为293、573K;名义应变速率为1200、3100、5100s-1,获得不同条件下的真应力-应变曲线。利用透射电镜对应变率为3100s-1压缩试样进行显微组织观察,探讨不同温度、不同成分合金强化相的演变规律,阐明稀土相在绝热温升条件下的耐热机制。结果表明,含0.2%Ce合金的吸收能力最强,其抗冲击性能最高。当应变率为3100s-1,温度为293K时,屈服强度达到614MPa,明显高于其他成分合金。温度为573K时,合金屈服强度降低。随着应变率的升高,合金的硬度值降低,θ′相的体积分数减小,开始长大粗化,且向θ相转化,但含0.2%Ce的合金中θ′相的转化最慢。
2519A aluminum alloys with different Ce contents were investigated with the true stress-strain curves at different temperatures of 293 and 573 K and different nominal strain rates of 1200, 3100 and 5100 s-1 in dynamic impact testing by split Hopkinson pressure bar （SHPB）. The microstructures of the impacted samples were observed by transmission electron microscopy （TEM） to examine the precipitated phase evolution and the interaction mechanism of heat-resistant phase at adiabatic temperature. The results indicate that the absorbing ability of the alloy with 0.2% Ce is the highest in the alloys with 0% Ce, 0.2% Ce and 0.4% Ce, and the impact resistance is the best. The yield strength reaches 614 MPa at 3100 s1, 293 K and it decreases at 573 K. With increasing the strain rate, the hardness of different alloys decreases, the volume fraction of 0＇ decreases and the growth and coarsening of θ＇ become obvious. The transformation of θ＇ into θ occurred, and the transformation rate is the slowest for the alloy with 0.2% Ce.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2013年第1期120-125,共6页
Rare Metal Materials and Engineering
基金
国家重点基础研究发展计划资助项目(2005CB623706)
