(西安建筑科技大学 冶金工程学院，西安 710055)
摘 要: 采用普通熔铸法制备含铁3%(质量分数)的铝铁二元合金，研究多道次往复搅拌摩擦加工(Friction stir processing, FSP)对合金显微组织的影响。结果表明：进行1~3道次往复FSP后，各道次加工区组织不均匀；随着加工道次的增加，组织均匀细化程度增大。合金铸态组织由α-Al和粗大针状Al3Fe相组成，经3道次FSP后，搅拌区组织明显细化。原始铸态组织转变为细小等轴的再结晶晶粒，尺寸为2~5 μm，并且部分晶粒中出现层错；粗大的Al3Fe针状相被破碎成长度小于1 μm的细小粒状，弥散分布在铝基体晶界和晶粒内部，细化的Al3Fe粒子呈现孪晶结构。
关键字: 铝铁合金；Al3Fe相；显微组织；搅拌摩擦加工
（School of Metallurgical Engineering, Xi’ an University of Architecture and Technology, Xi’ an 710055, China）
Abstract:Al-3%Fe (mass fraction) binary alloy was prepared by fusion casting. The effect of reciprocating multi-pass friction stir processing (FSP) on the microstructure of the alloy was studied. The results show that the microstructure of each pass in stir zone is non-uniform after one to three passes reciprocating FSP. With the increase of processing passes, the degree of uniformity and refinement of the microstructure increases. The as-cast alloy is composed of the α-Al and coarse needle Al3Fe phases. The microstructure in stir zone is significantly refined after three passes FSP. The as-cast microstructure in the stir zone is changed into fine equiaxed recrystallized grains with the size of 2−5 μm, and stacking fault appears in some grains. Coarse needle Al3Fe phases are broken into granular phases with the length of less than 1 μm, and disperse in Al matrix grain boundary and grain interior. Refined Al3Fe particles present twin structure.
Key words: Al-Fe alloy; Al3Fe phase; microstructure; friction stir processing (FSP)
