In-Situ Alumina/Aluminate Platelet Composites
نویسنده
چکیده
Alumina composites containing in-situ-formed hexaluminate (LaAl,,018, LaMgAl,,O,,, SrAl12019, and Mg,NaAl,,O,) platelets can be pressureless-sintered to high density. The grain morphology of the aluminates can be controlled by composition. A peak toughness 50% higher than that of alumina is obtained at 30 vol% aluminates, with a modest reduction (10%) in hardness and Young’s modulus. Although crack-bridging by aluminate platelets is apparently operating, the maximum toughness is intrinsically limited by the low cohesive strength of these layer compounds.
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