Influence of alumina morphology and microstructure on its strength

A study on the influences of alumina morphology and microstructure on its strength has been carried out. The alumina hydrate grain growth types are classified by SEM observations based on its microstructures. It is found that agglomerated alumina hydrate particles have much more opportunities to be strengthened than those particles which grow individually. The strength of the agglomerated alumina particles will be kept higher because the water vapor can be released gradually through the gaps among the agglomerated hydrate particles during calcinations without damage of the whole grain microstructure of the particles. The better control of agglomeration and growth processes in precipitation and smoother calcinations are the key solutions for obtaining stronger alumina product.