摘要
分析了经过RE、Ti变质ZA27合金的非平衡凝固过程,获得的合金铸态组织是由枝晶α相、枝晶边缘的β相以及呈网状分布的晶界共晶体组成。这种能降低材料塑韧性的网状组织用固溶淬火处理可以消除,进而提高合金的塑韧性。利用投射电镜对合金铸态组织的微观结构进行了研究,发现在枝晶心部存在着调幅分解产物———"类织物",并说明了类织物的生成过程。此外,研究了RE、Ti使合金组织细化的变质机理。
It is analyzed that the process of un-equilibrium solidification of Z A27 alloy modified by adding RE and Ti.The as-cast structure of ZA27 alloy is m ade up of dendrite α phase,β phase and ternary eutectic which is net structure reducing the plasticity- toughness pro perties.Ternary eutectic can be eliminated by quenching, and the plasticity- t oughness capacity of ZA27 alloy is improved.By observing the as-cast microstruc ture of ZA27 alloy by TEM,the spinodal transformation is occurred in the center of dendrite and then form the tweed-like microstructure,meanwhile the growth pr ocess of which is showed.The modification mechanism that the addition of Ti and Re to the ZA27 alloy can refine microstructure is studied.
出处
《铸造》
CAS
CSCD
北大核心
2003年第7期484-487,共4页
Foundry
基金
四川省重点科技研究项目(川教科(1999)26号)。
关键词
非平衡凝固
变质
共晶体
调幅分解
un-equilibrium solidification
modification
eutectic
spinodal
