Recycling of Alumina Power After Plasma Spraying

The possible reuse of powder Al2O3 waste formed in manufacturing of ceramic refractory products by plasma spraying was studied. The powder alumina waste was found to be individual particles α- and γ-Al2O3 and their conglomerates and also included iron oxides in the form of Fe2O3 and Fe3O4. It was shown that the plasma-spraying powder waste had to be purified of Al2O3 conglomerates and iron oxides in order to reuse it. For this purpose, powder waste should be sifted through a sieve and subjected to magnetic separation. It was established experimentally that such a powder can be reused for applying coatings and fabricating products by plasma spraying without degrading their quality