The Ti-6Al-4V alloy is widely utilized in the aerospace industry for applications such as turbine blades, where it is valued for its mechanical strength at high temperatures, low specific gravity, and resistance to corrosion and oxidation. This alloy provides crucial protection against oxidation and thermal damage. A thermal barrier coating (TBC) typically consists of a metallic substrate, a bond coating (BC), a thermally grown oxide (TGO), and a topcoat ceramic (TC). This study aimed to investigate laser parameters for forming a TBC with a NiCrAlY bond coating and a zirconia ceramic topcoat, which contains 16.0% equimolar yttria and niobia. The coatings were initially deposited in powder form and then irradiated using a CO₂ laser. The parameters of laser power and beam scanning speed were evaluated using scanning electron microscopy and X-ray diffraction. The results indicated that the optimal laser scanning speed and power for achieving the best metallurgical bonding between the substrate/BC and the BC-TGO/TC layers were 70 mm/s at 100 W and 550 mm/s at 70 W, respectively. Laser-based layer formation has proven to be a promising technique for the application of TBC.

Ti-6Al-4V alloys with a thermal barrier coating (TBC) have been applied in aeronautical components as turbine blades to provide oxidation resistance and thermal protection, enabling higher operating temperatures and extending component lifespan. Research into TBCs with laser surface modification has investigated improving their mechanical and thermal properties. This study assessed the creep behavior of Ti-6Al-4V alloy with a TBC, where the coating was applied via CO₂ laser-remelted plasma spraying. Creep tests were conducted at a constant temperature and a load ranging from 500 to 700 °C at 125 MPa. The microstructure and fractography of the specimens were also investigated. The investigation also included microstructural and fractographic analyses of the specimens. The results indicate that the laser-remelted TBC provided effective thermal protection and increased oxidation resistance, with the stationary creep rate at 600 °C reduced by 50% and the creep rupture life extended by 20%. Observations revealed typical ductile fractures characterized by equiaxed dimples and a homogeneous microstructure with an equiaxed dual-phase (α+β) structure near the fracture zone.

The Ti-6Al-4V is a very important alloy in the aerospace industry in the manufacturing blades for aircrafts turbines and structural forgings. However, one of the major factors limiting the life of titanium alloys in service is their degradation due to gaseous environments especially to environments containing oxygen at elevated temperatures during long-term. Some coatings have been discovered as layers of protection called TBC (Thermal Barrier Coating). The TBC provides the protection and allows reaching the higher operating temperature to increase the efficiency of the turbines without changing the mechanical properties of the titanium. The top coat ceramic aims to protect alloys against corrosion, oxidation and thermal protection. However, because of the limitations of the composition 7 YSZ (commercial zirconia stabilized with 7.6 ± 1 mol % yttria) other stabilizing of the tetragonal phase of zirconia such as tantalum and niobium has been studied to overcome these limitations. The present study the TBC are composted with the Ti-6Al-4V (metallic substrate), NiCrAlY (bond coat), thermally grown oxide (TGO) and the ceramic topcoat ZrO2-YO1.5-NbO2.5. The zirconia ceramic was co-doped with yttria and niobia with 14.5, 16.0 and 17.5 mol%. The deposition process the bond coat and power ceramic were by CO2 laser and the TGO was forming by vacuum thermal treatment in 1100 °C. The objective of the study is the comparison for a potential protection of this ceramic coating described above with the zirconia-yttria ceramic commercial. The samples were analyzed by microscopy and EDS for the morphology analysis and chemical analysis of the layers obtained. The SEM analysis showed finer grains and nanofissures for the ceramic composition of 14.5 and 17.5 mol % and showed coarse grains for the composition of 16.0 mol %. At high temperatures the coarse grains tend to have better mechanical properties, indicating that the composition of 16.0 mol% better meets the desired application.