A novel method to control agglomeration of ultrafine YAl2 particles in YAl2p/MgLiAl composite

A MgLiAl matrix composite reinforced with modified ultrafine YAl₂ particles was developed by stirring casting, in which YAl₂ particles were modified by milling YAl₂ and Mg particles. The effects of milling on the microstructures of YAl₂ particles and the dispersity of YAl₂ particles in YAl₂-Mg mixture were investigated. The microstructures and mechanical properties of the composite were presented. The results show that, after mix milling, elemental magnesium exists around YAl₂ particles and YAl₂ particles distribute homogeneously in YAl₂-Mg mixture. YAl₂-Mg mix milling is greatly beneficial to control agglomeration of ultrafine YAl₂ reinforcement in matrix, and the reinforcement is uniformly distributed in the matrix. The tensile strength of the 5 vol.% YAl_2p/MgLiAl composite increases by 90% as compared to the matrix alloy, while the elongation is keep at 7%.