Porous Al2O3/Al metal ceramics prepared by the oxidation of aluminum powder under hydrothermal conditions followed by thermal dehydration: II. Composition and microtexture of the composites

The microtexture of Al2O3/Al composites with different oxide contents forme d in the hydrothermal treatment of aluminum followed by thermal decompositi on of boehmite is examined by a set of adsorption and structural analysis t echniques. Two main types of alumina microtexture are found: relatively loo se agglomerates of amorphous particles and highly ordered aggregates of wel l-crystallized primary blocks of a larger size, the fraction of which incre ases with the oxide content of the composite leads to an increase in the fr action of micropores and a decrease in the fraction of mesopores. The mecha nism of thermal decomposition of boehmite prepared by the hydrothermal oxid ation of aluminum is refined.