Composites of Magnesium and Titanium-Aluminum-Carbide
Recently, the MAX phase group at Drexel University succeeded in fabricating Mg-Ti2AlC nanoscale composites wherein molten magnesium spontaneously infiltrates porous Ti2AlC preforms. Ti2AlC is a family of ternary carbides and nitrides that combine some of the best properties of metals and ceramics. When molten magnesium (Mg) infiltrates a porous Ti2AlC preform the resulting composites are light-weight, stiff, and quite strong.
The MAX phases’ structure is naturally layered so when they are compressed, one of their main deformation modes is the formation of kink bands. Similarly, if one loads a deck of cards edge-on, at a certain load, the entire deck will buckle irreversibly and form a kink band.
This colorized scanning electron microscope (SEM) image shows the fractured surface of a Mg-Ti2AlC composite. The red folds are kink bands of Ti2AlC reinforced with magnesium. The blue and orange swirls are nano-crystalline magnesium.
The image has been colored to resemble a fire-breathing dragon.
Image credit: Babak Anasori, Michel W. Barsoum/Drexel University (2011)
Babak Anasori is a Ph.D. candidate in Department of Materials Science and Engineering at Drexel University, Philadelphia, Pennsylvania. He, and his advisor Prof. Michel W. Barsoum, are currently working on the fabrication and characterization of these composites.
This research was supported by the Army Research Office (No. W911NF-07-1-0628).