晶粒细化工艺对ZL205A合金偏析缺陷的影响  

Effects of Improvement of Grain Refinement on Segregation in the ZL205A Alloy

作　　者：郑卫东[1,2] 阮磊[3] 厉沙沙[1,2] 罗传彪[1,2] 杜旭初[1,2] 黄粒[1,2] 

机构地区：[1]中国航发北京航空材料研究院 [2]北京市先进铝合金材料及应用工程技术研究中心 [3]中国运载火箭技术研究院物流中心

出　　处：《特种铸造及有色合金》2017年第7期792-795,共4页Special Casting & Nonferrous Alloys

摘　　要：采用金相显微镜(OM)和ProCAST软件,研究了晶粒细化工艺对ZL205A合金偏析缺陷的影响。结果表明,通过优化Al-5Ti-B中间合金添加工艺(两步添加),可增强合金的晶粒细化效果,提高其流动性、力学性能、抗热裂能力以及铸造性能;在凝固末期,ZL205A合金会形成晶间搭桥,加强了晶间结合力,而晶粒细化有利于增大晶粒之间的接触面积,扩大晶间搭桥面积,有效提升晶间的结合力,使合金热裂倾向降低,因此减少ZL205A合金的偏析缺陷。By using OM and ProCAST software, effects of grain refinement technology on the segregation in ZL205A alloys were investigated. The results show that microstructure of the ZI.205A can be refined significantly after the multistep addition of Al-5TiB alloy. The mechanical properties, casting proper- ties, flow ability and thermal cracking performance of the ZL205A alloy can be improved effectively. The grain bridge can be formed in the ending process of the solidification, which enhances the bonding force among the grain boundary. The grain refinement can increase significantly the contact area among the grain boundaries. Therefore, the bonding force of the grain boundaries is improved obviously with the relative slow intergranular separation process, which decreases the hot tearing tendency and the seg- regation in the ZL205A alloys.

关 键 词：ZL205A 细化处理 偏析 铸造工艺 

分 类 号：TG292[金属学及工艺—铸造]