Effect of the structure and chemical inhomogeneity of rapidly solidified powders on the properties of aluminum alloys

Abstract

The paper examines the effect of chemical and structural inhomogeneity formed in the rapid crystallization of aluminum powders on the structure and mechanical properties of alloys produced from these powders. The powders are obtained by high-pressure water atomization. High-strength and high-temperature Al-Zn-Mg, Al-Zn-Mg-Cu, Al-Fe-Cr, Al-Cr-Zr, and Al-Fe-Ce alloys additionally doped with transition metals and scandium are studied. Auger electron spectroscopy, secondary ion mass spectroscopy, and scanning and transmission electron microscopy are used. To examine mechanical properties, tensile tests at room and elevated temperatures are used. The contribution of different doping elements to the segregation and formation of an oxide film on the powders and their effect on the phase composition and mechanical properties are studied. It is shown that the cooling rate determines characteristics of the alloys.