Reaction Synthesis of ZrAl3 Intermetallic Compound and Its Nucleation Behavior

Using self-propagating high-temperature synthesis (SHS) reaction, ZrAl3 intermetallic compound was fabricated from Zr and Al elemental powders and its reaction behavior was investigated by XRD, DTA and SEM analysis. The result reveals that the synthesis process of ZrAl3 begins with solid-solid reaction between Al and Zr, and then further extends to solid-liquid reaction, and finally was completed at afterburning stage. The ZrAl3 grain takes on irregular block-like morphology and many sunken dendrites appear on its surface. In Zr-Al system, when the ratio of Zr/Al is ≤ 1, the formation of ZrAl3, the only phase, is independent on the expected composition of starting mixtures. Finally, the nucleation behavior of ZrAl3 was discussed.