The major failure mechanism in thermal

barrier coatings (TBCs) is the formation of a thermally grown oxide (TGO) layer at the bond coat/zirconia interface. The introduction of single-layer alumina or graded alumina/zirconia interlayer offers a potential solution to this problem by incorporating an oxygen diffusion barrier into the TBC system, thereby reducing the TGO growth rate [13]. By controlling the oxide/TBC interface formation, better adhesion and minimum thermal stresses could be achieved [14]. Pulsed laser deposition (PLD) is quite easy to produce multilayer films composed of two or more materials. One of the major advantages is that the stoichiometry of the target can be retained this website in the deposited films. This is due to the high rate of ablation, which causes all the elements to evaporate at the same time [15, 16]. The present work has focused on the development of Al2O3/ZrO2 nanolaminate thin films in order to stabilize the tetragonal phase of zirconia at room

temperature as a function of ZrO2 layer thickness. Methods Al2O3 (99.99% purity) and ZrO2 (99.99%) pellets of approximately 25 mm in diameter and approximately find more 3 mm in thickness were prepared and sintered at 1,673 K for 6 h and used as targets for PLD. The deposition was performed using KrF excimer laser (λ = 248 nm), and other deposition parameters were reported elsewhere [17, 18]. Si (100)-oriented substrates of dimension 10 mm × 10 mm × 0.5 mm (n-type phosphorous doped with a resistivity of 20 to 30 Ω cm) were used for the deposition of films. Multilayers, which consist of Al2O3 and ZrO2, of 10:10, 5:10, 5:5, and 4:4 nm with 40 bilayers were deposited at an optimized oxygen

partial pressure of 3 Pa at room temperature. Before the deposition of the multilayers, deposition rates of the individual layers Astemizole were determined accurately by measuring the thickness of each layer using a Dektak profilometer (Dektak 6M Stylus Profiler, Veeco, Plainview, NY, USA). All the multilayer samples were analyzed by https://www.selleckchem.com/products/AZD1480.html conventional X-ray diffraction (XRD; INEL XRG–3000 Diffractometer, Artenay, France). High-temperature XRD (HTXRD; INEL XRG–3000 Diffractometer attached with a curved position-sensitive detector and Bühler 2.4 HDK high-temperature camera, Hechingen, Germany) was performed to study the structural changes in the 5:5-nm film as a function of temperature in the range 298-1,273 K. A Pt-Re thermocouple was used for measuring the temperature of the sample. A heating rate of 10 K/min, cooling rate of 25 K/min, and soaking time of 5 min were used. The patterns were recorded in steps of 100 K, in vacuum of the order of approximately 2 × 10−3 Pa for 30 min. For the cross-sectional transmission electron microscopy (XTEM) analysis, the specimen (10 mm × 10 mm × 0.5 mm) was cut into small rectangular pieces using a wire saw. Two of these were glued, making the film surface face-to-face with a special adhesive and cured at 130°C for 1 h.