Tensile properties and formability of Mg-Li alloys grain-refined by ECAE process

ECAE process is applied to Mg-Li alloys to obtain samples with fine grain size in order to improve their tensile properties and formability. The microstructures of the ECAE samples show that the grains of specimens subjected to ECAE process only once (l-pass) are elongated towards 30 degrees from the extrusion direction while a homogeneous microstructure is obtained when ECAE process is repeated four times (4-pass). Annealing after ECAE process results in softening of the alloys due to recrystallization and coarsening of beta phase (Li solid solution). 4-pass specimen of LZ101 annealed at 100 degreesC exhibit a fracture elongation of 94% indicating superplastic-like deformation even at room temperature. 85% compression of LZ101 alloy at room temperature without cracks can be obtained using 4-pass specimens.