Study of Effects Distribution of Alloying Elements in Formation of Intermetallic Phases for Mg Alloys AZ91 and AM50

Abstract

Magnesium alloys have great use in automotive industry and as construction materials. These alloys are characterized by low density and good processing capabilities. The purpose of this paper was research of microstructure, constituent phases and distribution of elements and chemical composition of magnesium with aluminum alloys: AZ 91 and AM 50. These alloys are included in the group of alloys for casting; testing samples were taken in the longitudinal direction and transverse to the direction of hardening. Microstructure is investigation with light and electronic microscope (SEM and ESMA). Obtained results have proven that microstructure of alloys consisting of primary crystals rich with Mg-phase α, precipitations of inter metallic phase (β) - Mg17Al12 and another phase Mg2Si. From the samples analysis we can concluded that the distribution of elements in testing samples was optimal, and this distribution makes these alloy very suitable for casting.