Cerca nel sito per parola chiave

pubblicazioni - Memoria

Examples of the use of optical spectroscopy to detect the damage of thermal barrier coatings during cyclic oxidation

pubblicazioni - Memoria

Examples of the use of optical spectroscopy to detect the damage of thermal barrier coatings during cyclic oxidation

Nell’ambito degli studi dei meccanismi di degrado dell’ade vengono presentati i risultati di mappature automatiche, ottenute su rivestimenti di barriera termica ceramica per componenti di turbine, con due tecniche ottiche non distruttive: la piezo-spettroscopia di fotoluminescenza su barriere termiche colonnari e il Raman su barriere prodotte con termospruzzatura al plasma.

Results of photoluminescence piezospectroscopy (PLPS) mapping of TGO stress level at the interface between BC and TBC is presented. Measurements were performed on a series of specimens with EB-PVD TBC and Pt aluminised bond coat, aged in cyclic oxidation tests at 1100°C (cycle duration 2h, total high temperature exposure from some tenths to about 800 hours- 600 thermal cycles). A good agreement was found between PLPS quantitative results (compressive stress level of TGO calculated as mean value of data measured at some hundreds positions) and metallographic analyses performed afterwords on specimen sections. The stress intensity reduction results to be indicative of the interface degradation. In the second part of the paper potentialities of Raman spectroscopy mapping are enlightened and problems encountered in applying it to APS TBCs degradation are discussed.

Progetti

Commenti