材料期刊网

Al - Li alloys are of considerable interest because of their novel properties suitable for aerospace applications. The precipitation hardened Al-Li-Cu-Mg-Zr alloys have attracted plentiful interest. An investigation was made to study the influence of grain structure on microstructure, tensile properties and fracture behavior. The results show that tensile properties are impaired when grain structure changes from fully unrecrystallized, recrystallized to a little partially recrystallized grain structures. The sample with fully unrecrystallized grain structure fractures in a transgranular mode and possesses higher tensile strength due to a contribution of strong texture. The recrystallized and a little partially recrystallized grain structures fail in a mixed mode of intergranular and transgranular cracking. In the latter grain structure, intergranular region is larger while tensile properties are lower. In addition, an attempt is made to discuss these experimental results.