Modification of Fe and Al elemental powders' sintering with addition of magnesium and magnesium hydride

摘要

An attempt to modify sintering of iron and aluminium elemental powders with use of small additions of Mg and MgH_2 was presented in this paper. The kinetics of such modified sintering was investigated using DSC technique, XRD analysis and SEM observations. Significant changes in the mechanism of exothermal formation reaction of Fe-Al intermetallic phases in compositions doped with magnesium and its hydride was observed. Initiation temperature of Self-propagating High-temperature Synthesis (SHS) reaction was pronouncedly shifted to lower value as compared with undoped composition. Influence of additions on the SHS reaction kinetics parameters was also calculated with use of the JMA model and changes of the Avrami exponent value of specific phase formation was noticed. Positive effect of MgH_2 addition on partial homogeneity of final product was also studied.