| Summary: | Instituto de Investigación en Metalurgia y Materiales. Doctorado en Ciencias en Metalurgia y Ciencias de los Materiales The effects of ingestion of airborne particles from pyroclastic events of actives volcanoes by aircraft turbines and the subsequent reaction with the thermal barrier coatings have attracted the attention of the scientific community in recent years. The reactions products of infiltration experiments, at 1250ºCfor 10 h, of the ceramics and thermal barrier coatings of lanthanum-gadolinium zirconates with molten volcanic ashes from Colima, Popocatepetl and Eyjafjallajökull volcanoes are presented and discussed as function of the Gd3+content. In the ceramics, five compositions, varying the Gd3+ contenting the solid solutions, were synthesized by the coprecipitation-calcination method and later pressing and sintering. These compositions include pure lanthanum and gadolinium zirconates, respectively. The study of the infiltration depth and identification, and in some cases quantification, of the reaction products between the molten volcanic ashes and the ceramics is carried out by scanning electron microscopy, chemical composition with energy dispersive X-ray spectroscopy, grazing incident X-ray diffraction as well as Raman spectroscopy. The LZO ceramics presented the greatest infiltration resistance against all the molten volcanic ashes assessed. The phase characteristics and the reaction layers exhibit dependency with the gadolinium content in the lanthanum-gadolinium ceramics and show the presence of phases of apatites, monoclinic zirconia, tetragonal zirconia, cubic zirconia, spinel, anorthite and garnet depending on the interaction assessed. Additionally, the infiltration, at 1250ºCfor 1, 5 and 10 h; of the volcanic ashes deposited over gadolinium-zirconate-based thermal barrier coatings, manufactured by atmospheric plasma spray with a spray gun METCO 9MB. Afterwards, the study of infiltrated coating’s the reaction layers and phase characterizations were performed by scanning electron ...
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