Tailoring of growth morphology of the coatings by controlling the process parameters has recently generated significant attention since it has improved the performance and structural stability of the coatings. Therefore, tailoring of the microstructure was attempted on 7 wt% of yttria stabilized zirconia (7YSZ) thermal barrier coatings on NiCrAlY bond coated CM247LC EA/DS superalloy substrates by electron beam physical vapour deposition (EB-PVD). In the current study, multiple approaches such as shutter control, substrate temperature manipulation during deposition, and adjusting the angle of vapour incidence were employed to modify the typical columnar microstructure of 7YSZ. The tailored microstructures of the thermal barrier coatings (TBCs) were examined using X-ray diffraction (XRD), Raman spectroscopy, and field emission scanning electron microscopy (FESEM). These coatings were subjected to an isothermal oxidation (IO) and furnace cyclic test (FCT) to assess the oxidation and lifetime performance of the coatings. The structural and microstructural changes were further probed after IO by XRD, Raman spectroscopy, FESEM, and Vicker's microhardness measurements. The structural analysis revealed that the as-coated 7YSZ coating exhibits a stable tetragonal phase and no monoclinic phase after IO and FCT at 1273 K for 500 h and 200 cycles, respectively. The microstructural modification carried out by the change in the vapour incident angle with shutter in and out (VIA-SIO) method showed difference in the columnar microstructure. The tailored microstructures obtained by VIA-SIO method exhibit stable microstructural features after IO and FCT at 1273 K for 500 h and 200 cycles. The tailored microstructure of EB-PVD coatings had a comparable lifetime performance to that of the conventional 7YSZ columnar microstructured TBC. The results obtained from the current study suggest that the production of coatings with tailored microstructure from the columnar growth as a result of the process parameters adopted in the current study would provide improved performance with reduced thermal conductivity.

Sm and Zr co-doped BaTiO3 ceramics were investigated for their microstructure and dielectric characteristics. (Ba1 − xSmx)(Ti0.75Zr0.25)O3−δ (BSTZO) with x = 0.02, 0.04, and 0.06 mol V_O^·· = 1.98 × 1021 cm−3, at 773 K) than that of the other compositions. The measured maximum dielectric constant was found to be 1808, 2010, and 1736 for BSTZO pellet with x= 0.02, 0.04, and 0.06 mol

Friction reduction of AlTiN-based hard coatings is gaining much attention among researchers worldwide to broaden their tribological applications. Metal/non-metal inclusions, as well as the design of a novel coating architecture, are primarily focused on reducing friction while retaining wear resistance. This study investigates the tribological characteristics of magnetron sputtered AlTiN coatings by incorporating amorphous carbon (a-C) at different concentrations (5-25 at.%), as well as the compositionally graded AlTiN/a-C coatings (CGC). The XPS and Raman spectroscopy results confirm the presence of a-C features, while XRD reveals the formation of ceramic carbide phases in AlTiN coatings with higher carbon content and CGC coatings. The CGC AlTiN/a-C have shown a maximum hardness of 34.3 GPa and an elastic modulus of 321 GPa due to their refined grain structure. The CGC had the lowest friction (0.18 at 300 K and 0.37 at 673 K), as well as improved wear resistance (2.74 x 10(-7) mm(3)/Nm (300 K) and 4.93 x 10(-7) mm3/Nm (673 K)). The tribolayers are found to be mainly composed of sp(2)/sp(3) bonded a-C features (including C=C/C & horbar;C, C & horbar;N, and C & horbar;O), which reduces the friction force significantly. The CGC AlTiN/a-C coating has exhibited improved wear resistance behavior due to their finely grained structure and improved mechanical properties.

This chapter explores the use of silicone-based coatings for high-temperature applications. These coatings have unique properties that make them ideal for use in environments that experience extreme temperatures, such as aerospace, automotive, and industrial applications. This chapter also discusses the benefits of using these coatings, including their excellent thermal stability, resistance to oxidation and corrosion, and ability to maintain their properties over a wide temperature range. This chapter also looks at some of the key factors that influence the performance of silicone coatings, including temperature, stress, exposure, and curing time. In addition to the benefits mentioned above, silicone-based coatings offer other advantages such as flexibility, adhesion to various substrates, and chemical resistance. These properties make them suitable for use in harsh environments when exposed to chemicals, abrasion, and weathering. Finally, the chapter highlights the importance of curing conditions on the coating performance. In conclusion, silicone coatings play a vital role in many industries, and understanding their properties is essential for achieving optimal performance and durability.

(Ba0.9Sm0.1) (Sn0.05Ti0.95) O3 (BSST) ceramic powders were synthesized by solid state reaction route and were pelletized and sintered at 1673 K for 4 h. The BSST thin film was also prepared by electron beam evaporation technique by using the sintered pellets. X-ray diffraction of the BSSTO confirmed that the material has formed in crystalline nature and also in single phase. Raman spectroscopy was used to study the morphology, structure and phase transition behaviour of BSST bulk as well as thin film. The Raman analysis indicated that the film formed at 973 K by electron beam evaporation is less crystalline than that of the bulk BSST due to inadequate substrate temperature.

This chapter describes the use of nickel-yttria stabilized zirconia (Ni-YSZ) nanocomposite coatings as a ceramic diffusion barrier material in the nuclear vitrification furnace, which operates at high temperatures, high pressure, and corrosive environments. These coatings were developed utilizing the electron beam physical vapor deposition technique on metallographically prepared nickel (Ni) base superalloys, especially Inconel 690. The structural, morphological, nanomechanical, adhesion strength, and tribological characteristics of YSZ and Ni-YSZ nanocomposite coatings with various concentrations were investigated. The nanomechanical characteristics of YSZ coating deposited at various substrate temperatures and Ni–YSZ nanocomposite coating with variable weight percentage of Ni and YSZ are discussed in this chapter. It also looks into the interdiffusion effects and physicochemical factors that happen at the interface of coated and uncoated Ni-base superalloy/borosilicate glass. Compositionally graded coating of Ni–YSZ that was exposed to borosilicate melt for 10 h at 1373 K is also reviewed. The novel approaches and concepts for improving mechanical and tribological properties are explored. The use of these coatings for future nuclear vitrification furnace components, which can withstand harsh corrosive environments, is also discussed.

The microstructure of high temperature superconducting thin films grown on single crystal substrates by reactive glow discharge sputtering has been investigated. These films show a critical current density several orders of magnitude higher than the bulk polycrystalline superconducting materials. Understanding the role of defects in flux pinning has been the interest of the present investigation. TEM studies on these films have indicated both transformation and growth induced defects. Dislocation defects of both edge and screw type have been identified in YBa2Cu3O7-x films using such techniques as scanning tunneling microscopy and high resolution electron microscopy. The domain growth is another type of defect, the origin of which is related to anisotropy in the growth rates and lattice mismatch between the films and substrate. The ability to grow controlled grain boundary in thin films of bi-epitaxial junction constitutes perhaps the most significant breakthrough in the practical application of the thin films. The current status of understanding of the defects and a relation to achievable properties are reviewed.

In this chapter, recent trends in the development of advanced thermal barrier coating (TBC) and its architecture for enhancing gas turbine engine performance for aerospace applications are reviewed. Approaches toward the development of new ceramic top coat materials alternative to 7 wt.% of yttria-stabilized zirconia and processing techniques are described. The various degradation mechanisms when TBCs are subjected to extreme hot gaseous environments are described. This chapter focuses on the development of bilayer TBCs, which can be used to perform better than conventional TBCs. The chapter also reviews the recent progress in bilayer TBCs, performance, and future directions toward the development of more reliable and durable TBCs.

In the present study, 7YSZ/gadolinium zirconate (GZ) and 7YSZ/2.3 wt.% yttria doped gadolinium zirconate (Y-GZ) bi-layers were deposited onto the plasma sprayed bond coated Inconel-718 substrates by EB-PVD technique. Structural analysis revealed that GZ and yttria doped GZ has thermally stable pyrochlore structure and no phase transformation was observed even after thermal cycling test at 1523 K up to 75 cycles. Vicker's microhardness measurements of the coatings indicated that yttria doped GZ had improved mechanical properties than that of GZ. Hot corrosion behaviour of 7YSZ/GZ and 7YSZ/Y-GZ were evaluated with the mixture content of 45 wt.% of Na2SO4 and 55 wt.% V2O5 at 1273 K. Failure analysis of these TBCs was investigated by isothermal oxidation test (1273 K) and thermal cyclic test (1523 K). The results revealed that bi-layered 7YSZ/yttria doped GZ showed improved performance than that of the bi-layered 7YSZ/GZ TBC.

The objective of this work is to find out the optimised parameters to modify the surface properties of EN353 steel by increasing the hardness, and minimizing the loss in wear volume and enhancing the friction resistance in the material. The heat-treated samples of bare substrates were further plated with hard chromium followed by plasma nitriding to modify the surface of the EN353 steel. The nitrided chrome plated specimens were tested in 3.5 wt. % NaCl to test the corrosion properties. Microhardness and tribological properties results indicated that the plasma nitrided chromium plated EN353 steel offers higher hardness and low coefficient of friction when compared to other specimens used in the current study. The microstructure, wear and corrosion studies revealed that the modified layers reduce cracking and spalling on EN353 gear surfaces while electrochemical studies demonstrated an excellent corrosion resistance for the plasma nitrided EN353 steel. The usability of hard chromium plated and plasma nitrided EN353 material in place of hardened one improves the service life of the automotive gear application.

Highly durable and antimicrobial tantalum nitride/copper (TaN/Cu) nanocomposite coatings were deposited on D-9 stainless steel substrates by pulsed magnetron sputtering. The Cu content in the coating was varied in the range of 1.42–35.42 atomic % (at.%). The coatings were characterized by electron probe microanalyzer, X-ray diffraction, scanning electron microscope and atomic force microscope. The antibacterial properties of the TaN/Cu coatings against gram-negative Pseudomonas aeruginosa were evaluated using a cell culture test. The peak hardness and Young’s modulus of TaN/Cu with 10.46 at.% Cu were 24 and 295 GPa, respectively, which amounted to 15 and 41.67% higher than Cu-free TaN. Among all, TaN/Cu with 10.46 at.% exhibited the lowest friction coefficient. The TaN/Cu coatings exhibited significantly higher antibacterial activity than Cu-free TaN against Pseudomonas aeruginosa. On TaN, the bacterial count was about 4 × 106 CFU, whereas it was dropped to 1.2 × 102 CFU in case of TaN/Cu with 10.46 at.% Cu. The bacterial count was decreased from 9 to 6 when the Cu content increased from 25.54 to 30.04 at.%. Live bacterial cells were observed in the SEM images of TaN, and dead cells were found on TaN/Cu. Overall, TaN/Cu with 10.46 at.% Cu was found to be a potential coating composition in terms of higher antimicrobial activity and mechanical durability.

The present investigation reports on structural and microstructural information of the Ba0.5Sr0.5TiO3 (BST-0.5) film deposited over single crystalline Si (100), MgO (100), and LaAlO3 (100) substrate using pulsed laser deposition (PLD) method. In this study, initial experiments were carried out by depositing BST-0.5 films at 1023 K and with oxygen partial pressures of 0.13 Pa and 13.33 Pa on Si (100) substrates. X-ray diffraction (XRD) analysis indicated the formation of a highly crystalline perovskite cubic phase for film deposited at substrate temperature 1023 K. Another set of depositions were carried out at the substrate temperature of 873 K and 1023 K and with oxygen partial pressure of 13.33 Pa. The XRD analysis indicated that deposition at 13.33 Pa has produced BST-0.5 films of increased crystallinity at the substrate temperature of 1023 K. Raman spectra obtained for BST thin film deposited on these three substrates confirmed the formation of the cubic phase. BST thin films were also prepared on LaAlO3 (100) and MgO (100) to investigate the optical properties of film prepared under the best deposition conditions such as 1023 K and 13.33 Pa. The bandgap energies were found to be in the range of 3.93-3.97 eV for these substrates. The measurements of optical properties of the BST-0.5 film coated on LaAlO3 substrate showed about ~75% transmittance compared to MgO substrate. Higher extinction coefficient for the BST-0.5 thin film was observed for the film coated on MgO substrate in the UV and visible region compared to that of the film coated on LaAlO3 substrate. The refractive index as a function of wavelength was found to be 1.945 and 2.023 for BST-0.5 thin film coated on MgO and LaAlO3, respectively. The enhanced optical properties of the BST film coated on LaAlO3 substrate are discussed in relation to higher crystallinity and epitaxial growth of thin films obtained because of lower lattice mismatch.

Ceramic diffusion barrier coatings are inevitable in high temperature aerospace and nuclear applications to protect superalloys from oxidation and hot corrosion. Compositionally graded coating (CGC) of Ni-YSZ with five layers was deposited on an Inconel-690 substrate through electron beam physical vapor deposition (EBPVD) method. After heat treatment, the phase formation and crystallite determination in each layer of the CGC were studied by X-ray diffraction. Pulsed radio frequency glow discharge optical emission spectroscopy (RF-GDOES) showed outward diffusion of Ni towards the surface of the CGC. High resolution transmission electron microscopy (HRTEM) studies of the cross-sectional region of the heat-treated coating at 1273 K revealed no secondary phases within the coating as well as at substrate-coating interface. The corrosion behavior of Ni-YSZ coating under 3 M HNO3 medium showed that the heat-treated CGC of Ni-YSZ exhibited better corrosion resistance due to the formation of NiO than as-deposited Ni-YSZ coating.

The ongoing industrial revolution demands advanced tribological coatings for enhancing the performance of mechanical components by minimizing friction and wear-related losses. Recently, carbon-based coatings have been widely studied for many tribology applications. The functionality of the carbon-based coatings can be achieved by controlled modification of sp 2 /sp 3 hybridization ratio or hydrogen content during the deposition process. Amorphous carbon (a-C) coatings and hydrogenated a-C (a-C:H) or diamond-like carbon (DLC) coatings provide ultralow friction behavior due to the enrichment of sp 2 hybridized carbon features. Similarly, hydrogen-free carbon coatings with tetrahedral sp 3 bonded networks (70%) show higher wear resistance behavior. Crystalline diamond coatings with enriched sp 3 hybridized carbon features like microcrystalline diamond (MCD) and ultra/nanocrystalline diamond (U/NCD) coatings exhibit superhardness (50–100 GPa) and remarkable wear resistance behavior. Though these coatings provide superior tribo-mechanical properties at low-temperature (<100°C), tribological properties, however, rapidly deteriorate at elevated temperatures which limit their applications in different operating conditions. To overcome these limitations, researchers have developed duplex structures of suitable metallic and/or ceramic materials doped/embedded in an a-C matrix. This chapter reviews the recent innovations that have reported on all the aspects of carbon-based coatings.

Nuclear vitrification furnace made of Inconel-690 alloy fails prematurely due to alloy-borosilicate glass interaction by forming Cr rich secondary precipitates which results in the loss of corrosion resistance and incorporation of nuclear waste in the alloy-borosilicate interface. In this work, the development of a novel compositionally graded Ni-YSZ diffusion barrier coating using electron beam physical vapor deposition method was investigated to mitigate the issues related to inter-diffusion and elemental exchange across the alloyborosilicate melt without the addition of any nuclear waste. A comparative study on the interdiffusion effects of compositionally graded Ni-YSZ nanocomposite coating with increasing Ni content from 5 to 50 wt % subjected to diffusion annealing with and without borosilicate melt at 1373 K in air was carried out. No phase transformation was observed in Ni-YSZ coating subjected to diffusion annealing at 1373 K in air as observed from XRD analysis. FESEM-EDS analysis confirms the formation of NiO and grain growth of NiO in YSZ matrix after heat treatment. Raman spectroscopic studies confirmed the outward diffusion of Ni from the adjacent Ni rich multilayer to YSZ top coat and the formation of NiO at the surface of the Ni-YSZ nanocomposite. In contrast, there was no elemental exchange across the interface between nanocomposite coating and adhered borosilicate layer as there was no traces of NiO on the surface of the glassy layer. The wear behaviour was studied on the compositionally graded Ni-YSZ nanocomposite coatings subjected to high temperature diffusion annealing with and without borosilicate glass using a linear reciprocating tribometer by analyzing different modes of wear scar and the chemical changes inside the wear track using Raman spectroscopy. The observation of higher hardness and wear resistance obtained for the diffusion annealed Ni-YSZ nanocomposite was found to be due to the formation of NiO on the surface of the coating.

In this present work, a one-step hydrothermal approach was employed for the synthesis of ternary metal sulfides (TMS) for the preparation of high performance electrochemical supercapacitor electrode materials. Powder X-ray diffraction confirmed the formation of rhombohedral structure of NiS, hexagonal structure of the CoS and cubic structure of Ni1-xCoxS. The peaks obtained in the Fourier transform infrared spectroscopy (FTIR) also confirmed the formation of NiS, CoS, Ni1-xCoxS (x = 0.1,0.2 & 0.3) compounds. Field emission scanning electron microscopy revealed severe agglomeration and spongy microstructure with decreasing Ni content, while fine distribution of particles with less porosity with low Ni content in Ni1-xCoxS.The electrochemical behaviour of the fabricated Ni0.8Co0.2S electrode exhibited high specific capacitance of 71.92F/g at 5 mV/s in a potential window range from 0.25 to -0.3 V in 0.1 M nonaqueous electrolyte of TEABF4 in acetonitrile (AN) at room temperature. An excellent cycling stability was obtained up to 5,000 cycles with 87% capacitance retention. (c) 2021 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International e-Conference on Advancements in Materials Science and Technology.

Herein, a very simple, solvent free, scalable, and single-step approach to prepare organometal halide perovskite powders via mechanochemical synthesis followed by the deposition of perovskite films by spin coating is reported. This work particularly deals with various parameters that influence the crystallization process and morphology (hyperbranched) of methylammonium lead iodide films. Moreover, the influence of growth temperature on the morphology and the transition from tetragonal to cubic structure are investigated. The mechanosynthesized perovskite provides hyperbranched morphology and crystalline films in a hexagonal shape and serves as a better precursor for the absorber layer in perovskite solar cells.

Surface modifications have been applied to metal in order to improve the mechanical, chemical and physical properties, such as wear and hardness. Surface modification is found on the part surface of the automobile parts like turbochargers. Surface modification of stainless-steel alloy by plasma treatment is achieved using different gases such as air, nitrogen, argon and helium. The objective of plasma surface modification is to enhance the surface wettability, reduce surface friction, to reduce the wear rate and to avoid surface crack propagation on the components, to improve of surface properties against wear and other factors. In this project SS310 material is selected as the base material which is used for turbocharger. This SS310 material is machined and undergone plasma nitriding at a temperature of 450 ?C for 4 h. The plasma nitrided specimens have undergone different tests such as roughness, wear and hardness From all the test results, it is concluded that the material undergone heat treated plasma nitriding exhibits better mechanical and tribological properties such as roughness, hardness and wear resistance for the automobile components. This brings better service life of mating components in a successful way. ? 2020 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the 3rd International Conference on Frontiers in Automobile & Mechanical Engineering.

Metal-ceramic nanocomposite coatings have been applied to many industrial applications owing to their remarkable properties such as wear, corrosion and high temperature oxidation resistance than that of metals and alloys in high temperature environments. In this study, YSZ and Ni-YSZ nanocomposite coatings deposited by electron beam physical vapour deposition (EBPVD) for high temperature environments have been investigated. Initially friction and wear behaviour of YSZ coatings deposited at various substrate temperature were studied. Then the effect on wear response of Ni-YSZ nanocomposites with different Ni content were investigated using a ball-on-disc micro tribometer. The structural and tribochemical changes that occurred in the wear tracks of YSZ and Ni-YSZ coatings were investigated using field emission scanning electron microscopy and Raman spectroscopy. The results obtained on sliding wear and friction behaviour of these nanocomposite coatings suggest that 50 wt.% of Ni in YSZ nanocomposite provides good wear resistance behaviour than that of other coatings. Such an improvement in tribomechanical and wear performance of the nanocomposite coating could be attributed to the optimum amount of Ni which promotes the formation of NiO from Ni due to the frictional heat between nanocomposite coating and the sliding counter body in wear track as confirmed by Raman analysis.

Nanorods-like structured ternary metal sulfides of Ni1-xCuxS with various compositions (x = 0.1, 0.2 and 0.3), and binary sulfides of NiS and Cu9S5 were synthesised via a single-step hydrothermal process. The structural properties and the functional groups of the synthesized materials were characterized by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) studies. Surface structure and chemical composition of the samples were inspected using field emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray spectroscopy (EDAX). The electrochemical properties of the as-synthesised metal sulfide based electrodes were investigated by cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) analyses and the maximum specific capacitance (SC) of similar to 1092 F/g was achieved for the Ni-0.8Cu0.2S at a current density of 15 mA/g, while pure NiS and Cu9S5 electrodes showed the minimum SC of similar to 575 and similar to 70 F/g, respectively. Further, the electrochemical impedance studies (EIS) revealed low R-ct value (3.4 omega) for the Ni-0.8Cu0.2S electrode and improved electrochemical supercapacitor properties of Ni-0.8Cu0.2S electrode because of to the synergistic effect and its well crystalline nanorods structure which offers more electrochemical active sites for faradaic reactions and fast electrolyte ions diffusion in to electrode. Additionally, the stability performance of the Ni-0.8Cu0.2S electrode was performed at a fixed current density of 20 mA/g, and the Ni-0.8Cu0.2S sample possesses the good cycling stability with the retention of 80% capacitance after 3000 GCD cycles. These results demonstrate that the as-synthesised binary and ternary metal sulfides are suitable cost effective and pollution free electrode materials for supercapacitors.