Effects of trace yitrium addition and solution treatment on microstructure

tensile properties and corrosion behavior of Al-10Mg alloy were investigated by XRD （X-ray diffraction）

SEM （scanning electron microscope）

OM （optical microscope） and tensile testing. The results indicate that tensile strength and elongation of the alloy can be improved with Y addition

which is attributed to grain refinement and creation of Al4MgY discontinuously distributed along grain boundary strengthening grain boundary. The alloy with desirable mechanical properties

tensile strength of 261.8MPa and elongation of 4.3%

can be observed with 0.4% Y addition. With Y addition more than 0.4%

the tensile strength and elongation of the alloy are deteriorated as a result of Al4MgY phase continuously distributed along grain boundary decreasing adhesive strength of grain boundary. The Al-10Mg alloy containing Y free is typically characterized by interdendrite brittle fracture

while the alloy with Y addition is characterized by ductile fracture

resulting in the great increase of fracture toughness. Y addition is detrimental to corrosion behavior of the alloy due to strengthening interdendrite corrosion tendency.