The mechanical properties of cast Be-37.6Al-0.4Sc alloy were characterized by nano-indentation and tensile tests

and effects of Sc-alloying on the microstructure and fracture behaviors of the alloy were investigated via tensile fractography and optical metallography.With Sc alloying

the microstructure of the Be-Al alloy is converted from coarse columnar dendritics to uniform and fine equiaxed grain

which are responsible for improving strength and decreasing plasticity.The Sc-containing secondary phases presents the highest elastic modulus of 321.48 MPa

the highest hardness of 9.83 GPa and the lowest plasticity index of 0.803 compared with those of the matrix alloy.The secondary phases locating at the Be/Al interfaces is not acted as pre-existing micro-crack sources during the deformation

whereas the highly-faceted secondary phases within Be grains induced the formation of micro-cracks and resulted in the decrease of elongation.The failure mode of Be-37.6Al-0.4Sc alloy are characterized by brittle cleavage failure of Be regions and ductile dimple failure of Al regions compared with the Be-Al alloy.