摘要
分别采用铁模浇注、水冷模浇注和半连续铸造3种方式,通过拉伸试验、金相观察、扫描电镜观察、X射线衍射及透射电镜对Al-4.5Mg-0.7Mn-0.4Er合金的力学性能、组织进行了研究,结果发现增大冷却速度可以提高Al-4.5Mg-0.7Mn-0.4Er合金的强度;有利于合金凝固时Er、Mn在Al中形成过饱和固溶体,并且在均匀化退火以后析出形成细小、弥散分布的Al3Er和Al6Mn相。以细小弥散的第二相形式析出的Al3Er是铝合金中的有效强化相,对提高合金的性能、改善合金的组织有益。经过激冷浇注成形,合金的抗拉强度和屈服强度分别提高了14MPa和7MPa,伸长率稍有下降。
The mechanical properties and microstructure of Al-4.5Mg-0.7Mn-0.4Er alloy prepared with iron mold, water cooling mold and semi-continuous casting have been described by tensile testing, optical microscope, SEM (scanning electronic microscope), XRD(X-ray diffraction) and TEM (transmission electron microscope). It is found that increasing cooling rate can improve the strength of Al-4.5Mg-0.7Mn-0.4Er alloy, and be helpful for the formation of supersaturation solid solubility of Er and Mn element in Al during solidification process and for the precipitation of fine and dispersive Al3Er phase and Al6Mn phase after homogenized annealing treatment. Fine and dispersive Al3Er phase can be acted as the effectively strengthening phase in the Al alloy, which is helpful for improving the mechanical properties and microstructure of the alloy.
出处
《特种铸造及有色合金》
CAS
CSCD
北大核心
2007年第9期657-659,共3页
Special Casting & Nonferrous Alloys
基金
国家高技术发展计划(863计划)资助项目(2006AA03A207)