国内铝锂合金基础研究及应用技术开发

Basic Research and Application Technology Development of Al-Li Alloy in China

总结了国内在铝锂合金主合金元素Cu、Li以及微合金元素Mg、Ag、Zn、稀土的(微)合金化效果及作用机理方面的研究结果。在主合金元素的研究方面,重点阐述了铝锂合金强度随Cu+Li总原子分数及Cu/(Cu+Li)原子分数比例增加而提高,但晶间腐蚀(IGC)抗力则随Cu/Li比增加而逐渐降低的规律及相关机理。在微合金化元素研究方面,主要阐述了Mg+X(X=Ag/Zn)添加促进T_(1)(Al2CuLi)相形核并提高铝锂合金力学性能的机理,其强化效果的规律表现为:Mg+Ag+Zn>Mg+Ag>Mg+Zn>Mg,同时还阐明了添加微量Zn元素提高铝锂合金IGC抗力,而添加微量Ag则降低IGC抗力的现象及其机理;另外,还总结了稀土(RE)元素分别在高Cu/Li比铝锂合金(以T_(1)相为主强化相)及低Cu/Li比铝锂合金[以δ΄(Al_(3)Li)相为主强化相]中的不利影响及有利影响的作用机理。除此之外,简述了国内航天用2195铝锂合金旋压、摩擦搅拌焊、氩弧焊、化铣等应用技术的开发情况。

The basic research on the correlation between composition,microstructure and properties of Al-Li alloy is reviewed,including the alloying effect and mechanism of main alloying elements Cu and Li,and micro alloying elements of Mg,Ag,Zn and rare earth(RE).In the research of main alloying elements,it is described emphatically that the strength is enhanced with Cu+Li total atomic fraction and Cu/(Cu+Li)atomic faction ratio,but the IGC resistance is deteriorated with Cu/Li ratio,the corresponding mechanism is explained.In the research of micro-alloying elements,it is expounded that the samll addition of Mg+X(X=Ag/Zn)increases T_(1)(Al_(2)CuLi)precipitation rates and improves the strength,and the effect displays as Mg+Ag+Zn>Mg+Ag>Mg+Zn>Mg.Meanwhile,it is described that Zn addition increases IGC resistance but Ag addition decreases IGC resistance.Furthermore,the adverse and beneficial effects and related mechanism of RE elements in Al-Li alloy with higher Cu/Li ratio and low Cu/Li ratio are summarized,respectively.In addition,the application technology development of spinning,friction stir welding(FSW),argon arc welding,chemical milling of Al-Li alloy is briefely described.