Interfacial reaction behavior and thermal stability of barium zirconate-coated alumina fiber/alumina matrix composites

Solid-state synthesis and formation mechanism of barium hexaaluminate from mechanically activated Al2O3–BaCO3 powder mixtures

“…This morphological feature is similar to that of Ba-␤-Al 2 O 3 phase, formed through reaction between Al 2 O 3 and BaZrO 3 [22][23][24]. The elongated morphology of Ba-␤-Al 2 O 3 phase is believed to be due to preferred orientational growth through directional diffusion and mass transport of Ba along the basal plane [24]. These elongated Ba-␤-Al 2 O 3 particles can be used as a reinforcement [4] to enhance the fracture toughness of ceramic matrix composites through crack deflection and/or crack bridging, just like the functions of whiskers and fibers with large aspect ratios.…”

“…This morphological feature is similar to that of Ba-␤-Al 2 O 3 phase, formed through reaction between Al 2 O 3 and BaZrO 3 [22][23][24]. The elongated morphology of Ba-␤-Al 2 O 3 phase is believed to be due to preferred orientational growth through directional diffusion and mass transport of Ba along the basal plane [24].…”

In situ synthesis of alumina-matrix oxide/oxide composites by reactive sintering

“…Actually, Chen et al [51] have confirmed the distribution of Ba content in Ba-rich phase for ashot-pressed specimen. Accordingly, although Ba-b-Al 2 O 3 compound seems to have a composition close to BaO Á 7.…”

“…This is to say, a Barich phase appears at lower temperature, whereas an Al-rich phase forms at higher temperature. On the other hand, XRD analyses on hot-pressed samples of BaZrO 3 -coated Al 2 O 3 fiber/ Al 2 O 3 matrix composites also revealed the presence of Ba-b-Al 2 O 3 [50,51].…”