Study of the microstructural evolution of precipitation in AZ91 alloy

الملخص EN

Magnesium-based alloys have been the subject of several scientific research projects.

Their excellent mechanical properties have allowed their use in various fields such as aeronautics and automotive.

Phase transformations play a crucial role in the mechanical properties improvement; therefore the understanding of structural hardening due to the precipitation reaction is important.

The main objective of this work is to study the influence of the aging temperature on the precipitation mechanism in AZ91 () alloy.

It has been found that at high aging temperatures continuous precipitation is appeared and characterized by fine precipitates, however, discontinuous precipitation is observed under cellular form at low temperatures.

With increasing ageing time continuous precipitates can be also observed and they block the growth of discontinuous precipitates.

This phenomena influence directly the mechanical properties of such alloys, for that microhardness measurements are done to evaluate the mechanical properties variations as function of temperature, ageing time and so on.