April 22nd, 2021
Gas turbine engines are the workhorses of aviation and many corners of the energy sector. Rapid growth in each of these key market segments continues to drive demand for gas turbines that are both ultra-efficient and environmentally-friendly. In fact, industry experts predict that sales of gas turbine engines will top $2 trillion USD by 2031—reflecting the cumulative sales over a fourteen-year period. Naturally, satisfying this enormous demand calls for innovative material development focussed on both the underlying components (i.e. turbine blades) and the solutions used to protect them from harsh operating conditions (i.e. environmental barrier coatings).
At Saint-Gobain Coating Solutions, we supply a choice of thermal spray powders uniquely suited to EBC applications. In this article, we will explore the importance of EBC powders in both aerospace and energy gas turbine applications.
What do EBC Powders Do?
Advanced ceramic materials like silicon carbide (SiC) have long been prescribed for gas turbine applications, particularly for engines where operating temperatures may exceed thecapabilities of conventional nickel-based superalloys. Barrier coatings are used on most components deployed in the hot zones of gas turbines to prolong optimal performance at higher gas inlet temperatures. This applies to silicon carbide components too, despite their usually exceptional high temperature resistance – imparted by the formation of a silica-based patina at the ceramic’s interface.
Common combustion reaction products (i.e. steam) alter the oxidation resistance of silicon carbide components and degrade the protective silica layer. The oxidation kinetics are temperature- and atmosphere-dependent, so accelerated degradation of key components is expected in modern engines that push performance to new levels.
EBCs are usually composed of thermal spray powders deposited on the surface of silicon carbide components to enhance protection against gas erosion, and support material innovation for high-performance gas turbine components.
EBC Thermal Spray Powders from Saint Gobain
We have curated a range of advanced thermal spray powders based on barium strontium aluminium silicate (BSAS) and rare earth silicates (yttrium monosilicate, ytterbium disilicate, etc.) which meet the demands for high-purity EBCs in gas turbine applications. Our core competencies include custom synthesis of precision thermal spray powders with respect to user-defined chemistries and/or particle size and morphology. This allows us to tailor thermal spray powders to customer specifications, supporting research and development (R&D) of next-generation gas turbines with reliable EBC solutions capable of withstanding severe erosion and corrosion from both process gases and water vapor.