抄録
Magnesium is the eighth most abundant element in the earth's crust and also the third most commonly used structural metal following steel and Al. Several Al alloys used in automobile, aerospace, nuclear and sports industries are being replaced by Mg alloys due to their high specific strength and good damping capacity. The HCP crystal structure with a limited number of operative slip systems render Mg alloys inherently poorly workable. This drawback has restricted use of these alloys mostly in the as-cast condition. Present research endeavours the world-over are therefore mostly aimed at overcoming this drawback so that Mg wrought alloys find wider application. Just as Mg is a commonly used alloying addition to Al, so also Al in Mg alloys. We have used the processing map technique to study the hot deformation behaviour of Mg-Al alloys. The results show that the addition of Al improves workability at high speeds of deformation, which feature has direct implication to Mg-based component manufacture. It is also found that the tailoring of microstructure through thermo-mechanical processing (TMP) can be achieved as the addition of Al provides a variety of safe processing windows.
