Abstract
A brief study was performed to examine the influence of starting powder composition, starting powder particle size and spraying environment on the chemistry, phase assemblage and porosity of Al-Cu-Fe plasma sprayed coatings involving a quasicrystaliine phase. It was found that a loss of Al during spraying results from the extremely low thermal conductivity of the quasicrystaliine phase in the starting powders. This loss changes the bulk composition of the deposited coating and partially controls the phases that develop. Smaller starting powder particles tended to lose more Al and, therefore, form less of the quasicrystaliine phase. Larger starting powder particles did not lose Al to the same degree, and produced coatings with more of the quasicrystaliine phase. However, these powders produced coatings also had a higher amount of porosity.
