All solid-state sodium-ion batteries (ASS-SIBs) have great potential for application to large-scale energy storage devices due to their safety advantages by avoiding flammable organics and the abundance of sodium. In this study, plasma spraying was used to deposit Na 3 Zr 2 Si 2 PO 12 (NZSP) electrolyte for assembling high performance ASS-SIBs. NZSP electrolyte layers were deposited at different spray conditions using NZSP powders in different particle sizes. The factors influencing the microstructure and compositions of NZSP layers were examined by characterizing the compositions of splat and cross-sectional microstructures of the deposits. It was found that the preferential evaporation loss of Na and P elements occurs severely to result in a large composition deviation from initial powders and spray particle size is key factor which dominates their evaporation loss. The APS NZSP electrolytes present a dense microstructure with well bonded splats which is attributed to low melting point of NZSP. The apparent porosity of the as-sprayed NZSPs was lower than 3 %. The effect of annealing on the microstructure of APS NZSP was also investigated. The performance of typical APS NZSP was also evaluated by assembling an ASS-SIB battery with APS NaxCoO2 (NCO), Na 3 Zr 2 Si 2 PO 12 (NZSP) and Li 4 Ti 5 O 12 (LTO) as cathode, electrolyte and anode, respectively. Results showed that columnar-structured grains with a chemical inter-splat bonding were formed across the interfaces between electrodes and electrolyte. There is no evidence of inter-diffusion of zirconium, cobalt and silicon across the NCO/NZSP interface. With the preliminary battery, the solid electrolyte exhibited an ionic conductivity of 1.21 × 10 -4 S cm -1 at 200 o C. The SIB can operate at 2.5 V with a capacity of 10.5 mA h g -1 at current density of 37.4 μA cm -2 .

Surface coatings play a pivotal role in enhancing mechanical and functional properties of various materials. High Entropy Alloy (HEA) annealed coatings have garnered significant interest due to their potential to improve wear resistance and overall durability. This research presents a comprehensive study focused on the characterization of HEA annealed coatings. It focuses on evaluating their roughness and wear performance. In this research, a systematic approach is adopted to assess the effects of annealing on coating surface properties. The investigation begins with the deposition of the Al 0.1-0.5 CoCrCuFeNi and MnCoCrCuFeNi coatings using a well-established cold spray (CS) technique, followed by a controlled annealing process. The coating surface roughness is analyzed using profilometry and microscopy techniques. This offers insights into the changes induced by annealing. The wear performance of the annealed coatings is evaluated through tribological tests.

The previous results have shown that dense bismuth oxidebased electrolytes can be fabricated simply by plasma spraying owing to their low melting point. In this study, the Bi 2 O 3 – Er 2 O 3 –WO 3 electrolyte of high ionic conductivity was deposited by the cost-effective plasma spraying to assemble the SOFC for examining its electrochemical performance. The SOFC cell consisted of FeCr 24.5 metal support, NiO-YSZ anode, 10 mol% scandium oxide-stabilized zirconium oxide (ScSZ) electrolyte, (Bi 2 O 3 ) 0.705 (Er 2 O 3 ) 0.245 (WO 3 ) 0.05 (EWSB) electrolyte, and La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3 (LSCF) cathode. The ScSZ electrolyte interlayer was introduced between the anode and EWSB electrolyte to hinder the reduction of EWSB in the anode environment. NiO-YSZ, ScSZ, EWSB, and LSCF were deposited by plasma spraying on the metal support which was prepared by a press-forming-sintering process. The NiO-YSZ/ ScSZ/ EWSB/ LSCF single cell assembled with the as-sprayed ScSZ presented an open circuit potential of 0.90V at 600 °C and the maximum power density of 1130 mW cm -2 at 750 °C, 450 mW cm -2 at 650 °C, and 128 mW cm -2 at 550 °C. The plasma sprayed ScSZ electrolyte was then densified through impregnating using yttrium and zirconium nitrate solutions followed by annealing treatment. The single cell assembled with the densified ScSZ presented an open circuit potential up to 1.004V at 600 °C and the maximum power density of 1356 mW cm -2 at 750 °C, 619 mW cm -2 at 650 °C, and 163 mW cm -2 at 550 °C. The performance of the cell was significantly improved by the post-spray densification treatment of the ScSZ electrolyte. The present result shows that the high performance NiO-YSZ/ScSZ/EWSB/LSCF cell at intermediate temperatures can be successfully fabricated by plasma spraying.

High amorphous phase formation tendency, a desirable microstructure and phase composition and silicon evaporation are the challenges of spraying Yb 2 Si 2 O 7 environmental barrier coatings (EBCs). This research addresses these issues by depositing as-sprayed high crystalline Yb 2 Si 2 O 7 using atmospheric plasma spray (APS) without any auxiliary heat-treating during spraying, vacuum chamber, or subsequent furnace heat treatment, leading to considerable cost, time, and energy savings. Yb 2 Si 2 O 7 powder was sprayed on SiC substrates with three different plasma powers of (90, 72 and 53 kW) and exceptional high crystallinity levels of up to ~91% and deposition efficiency of up to 85% were achieved. The silicon mass evaporation during spraying was controlled with a short stand-ff distance of 50 mm, and an optimum fraction of Yb 2 SiO 5 secondary phases (<20 wt.%) was evenly distributed in the final deposits. The desirable microstructure, including a dense structure with uniform distribution of small porosities, was observed. The undesirable vertical crack formation and any interconnected discontinuities were prevented. Reducing the plasma power from 90 kW to 53 kW, while conducive for mitigating the silicon mass loss, was detrimental for microstructure by increasing the fraction of porosities and partially melted or unmelted fragments. The gradual decrease of the coating temperature after deposition alleviated microcracking but has an insignificant effect on the crystallinity level. Coatings annealed close to their operating temperature at 1300 °C for 24 hours demonstrated sintering and a crack healing effect, closing the tiny microcracks through the thickness. An improved coating composition was detected after annealing by the transformation of Yb 2 SiO 5 to Yb 2 Si 2 O 7 (up to ~10 wt.%).

This study investigates the solid particle erosion performance of cold sprayed tungsten carbide-nickel coatings using alumina particles as erodent material. After coating fabrication, specimens were annealed in an electric furnace at a temperature of 600 °C for 1 hour. The coatings were examined in terms of microhardness and microstructure in the as-sprayed (AS) and annealed (AN) conditions. Subsequently, the erosion tests were carried out using a General Full Factorial Design with two control factors and two replicates for each experimental run. The effect of the annealing on the erosion behavior of the coating was investigated at the two levels (AS and AN conditions), along with the impact angle of the erodents at three levels (30°, 60°, 90°). Finally, two regression models that relate the impact angle to the mass loss were separately obtained for the two cold spray coatings.

Stabilized bismuth oxide with fluorite structure is considered a promising electrolyte material for intermediate temperature solid-oxide fuel cells (SOFCs) due to its high oxygen ion conductivity. The ternary system, Bi2O3-Er2O3-WO3, is of particular interest because it is ionically conductive as well as thermally stable. This study investigates the quality of Bi2O3-Er2O3-WO3 (EWSB) electrolyte produced by plasma spraying. The phase structure and cross-sectional microstructure of plasma-sprayed EWSB were characterized by XRD and SEM. The as-sprayed EWSB was found to have a dense microstructure with well bonded lamellae. XRD analysis showed the formation of EWSB with δ-phase and a trace of β-phase, while the β-phase disappeared after annealing at 750°C for 10h. Electrical property tests revealed that the plasma-sprayed electrolyte also had excellent ionic conductivity (0.26 S cm-1 at 750 °C), making it a strong candidate for use in SOFCs at intermediate temperatures.

An internationally recognized best practice for disposing used nuclear fuels is to store them in specially designed containers in deep geological repositories. One type of spent fuel container is a carbon steel canister with a cold-sprayed copper coating. The aim of this study is to assess the impact of various factors on the ductility of this protective copper layer. The current investigation finds that there can be significant variability in ductility when feedstock powder size and chemical composition are changed while keeping spraying and heat treatment conditions constant. Test results show that the ductility of nitrogen-sprayed copper decreases with increasing hardness, but can be improved by raising annealing temperature from 300 to 600 °C. The effects of substrate geometry and process variations are discussed as well.

This study investigates the effect of heat treatment on the microstructure and tribological properties of TiB 2 -reinforced AlSi 10 Mg composite coatings produced by cold spraying. SEM and XRD analysis showed that the microstructure of the feedstock powder was well preserved in the as-sprayed material with uniformly distributed TiB 2 nanoparticles, some aggregated clusters, and a cellular-like network of fine eutectic Si particles embedded in an aluminum matrix. With increasing heat treatment temperature, the Si particles grew larger in size, but significantly fewer in number and a reduction in microhardness was observed due mainly to the elimination of the work hardening effect and coarsening of the Si particles.

In this study, Fe-based amorphous/nanocrystalline coatings with a composition of Fe 53 Cr 19 Zr 7 Mo 2 C 18 Si have been fabricated by high velocity oxygen fuel (HVOF) spray. Postspray annealing treatment at 750°C was employed to enhance the amorphicity of the as-sprayed coatings. The microstructure, corrosion resistance and algal adhesion behaviors of the as-sprayed and annealed coatings were characterized by scanning electron microscopy, transmission electron microscopy, laser confocal scanning microscopy, X-ray diffraction and electrochemical methods. Results show that the as-sprayed coatings exhibited excellent corrosion resistance and decreased algal adhesion, while the annealed coatings exhibited compromised anticorrosion performance but significantly reduced adhesion of algae.

Plasma spheroidization utilizing a plasma spray gun has been demonstrated for water-atomized stainless steel SUS316L powder. The angular particles were successfully spheroidized, and the D50 size of particles were decreased from 35 μm to 24 μm with 9 kW of processing power and to 15 μm with 17 kW of processing power. It was found that the high processing power of 17 kW generates a significant number of fine particles with the size of under 1 μm. By contrast, the powder formed on low processing power of 9 kW has better flow-ability and low cohesiveness, suggesting that an appropriate processing power exists to form the spherical powder suited for additive manufacturing

In this study, stainless steel powder is mixed with commercially pure iron and cold sprayed on steel in order to produce a metal composite with controlled properties. For these composites, porosity is very low, and annealing at 600-1100°C for an hour reduces it further. Annealing also sinters interparticle interfaces, leading to vastly improved fracture properties. Fully annealed single-component stainless steel exhibits a much higher strength than annealed CP iron, but adding just 20% stainless steel to iron produces a composite with the same fully annealed strength as that of stainless steel.

The main goal of the combined Cold Spray – Sintering technology development is to obtain high density ductile Fe- Al intermetallics based thermal barrier coatings as an alternative to conventional ZrO 2 coatings widely applied in industry. The task of this paper is to examine the structural changes of cold sprayed Al-AISI 316L composite coatings due to synthesis of Fe-Al intermetallics during annealing and find the conditions of high density composite formation. A dense Fe/Al intermetallic-Al composite coating is obtained. Three factors are found to play the main role in the structure formation of dense Fe-Al intermetallic composite coating: i) layered structure, ii) particle size and thickness of Fe and Al layers, iii) annealing temperature.

The equiaxed microstructure of 316L stainless steel coating was successfully deposited by low pressure plasma spraying (LPPS), which was different from the lamellar microstructure prepared by other thermal spraying technologies. In this article, the effect of substrate temperature during deposition process and post annealing treatment on the lamellar – equiaxed microstructural transition were investigated. The results indicated that the homogeneous equiaxed grains without lamellar boundaries coatings were observed when the deposition temperature was about 900 °C. Completely lamellar microstructural coatings were deposited at the substrate temperature of about 300 °C, and the lamellar microstructure can transform to equiaxed microstructure after annealing treatment. The hardness of equiaxed coating was lower than lamellar coating.

The present study investigates the microstructure and properties of cold spray coatings produced from gas-atomized CuAl10Fe5Ni5 powders. To obtain information relevant to ship rudder cavitation-erosion performance, GL-A shipbuilding steel, equivalent to S235, was chosen as the substrate material. Thick Cu-Al-bronze coatings were deposited on grit-blasted plates using a wide range of parameter sets with different powder treatments, nozzle geometries, gas and substrate temperatures, and particle impact conditions. Coating samples were examined via SEM and XRD analysis, cavitation tests were performed, and bond strengths were measured. Powder and single impact morphologies were also investigated and, along with coating properties and structures, are correlated with spraying conditions. The results indicate that cold sprayed bronze coatings have good potential for ship rudder protection.

In this study, lanthanum (LZ) and gadolinium zirconate (GZ) powders were prepared by spray drying and deposited on graphite substrates by air plasma spraying. Free-standing 1-1.5 mm thick LZ and GZ coating samples were obtained by mechanical delamination and subjected to long-term annealing in air at 1250 °C. Significant changes occurred during heat treating in the form of microstructure evolution, crystal structure ordering, and phase transitions as observed via SEM, XRF, and XRD analysis. These changes affected a number of coating properties, including hardness, porosity, fracture toughness, and thermal conductivity. In the first 20 h, thermal conductivity increased in gadolinium zirconate from 0.5 to 1.0 W/m·K and in lanthanum zirconate from 0.5 to 1.5 W/m·K.

This study evaluates the effects of heat treating on the microstructure, phase composition, and friction and wear behavior of plasma sprayed FeAl coatings. Fe-40Al feedstock powder was deposited on mild steel substrates by atmospheric plasma spraying and the coatings were vacuum annealed at 500, 650, 900, and 1000 °C. An examination of coating cross-sections revealed the presence of diffusion layers in the samples treated at 900 and 1000 °C. XRD analysis indicates that annealing at 650°C facilitates the transformation of Fe(Al) solid solution into FeAl intermetallic phase, resulting in an increase in coating hardness. At higher temperatures, however, Al depletion occurs along with a reduction in hardness. Tribological testing showed that both the friction coefficient and the effects of wear increased after heat treatment.

In this study, FeCrB coatings are deposited by wire arc spraying using powder cored wires to investigate the factors that affect thermal conductivity. Experimental results show that increasing boron content in the wires reduces oxide content in the coatings, which increases thermal conductivity. Annealing also increases thermal conductivity, which can be explained by grain growth and a reduction in porosity.

In this study, gas- and water-stabilized plasma torches were used to spray cesium-doped yttrium aluminum garnet (Ce:YAG) on different substrate materials and in large-area free-standing layers. The coatings were evaluated based on microstructure, crystallinity, and thermal stability, and tests were performed to measure porosity, hardness, phase composition, band-gap energy, and the presence of defects. Some coatings were also heat treated to determine how it changes their spectral response. The results of the examinations and tests are presented in the paper.

Thermal spraying produces coatings with relatively rough surfaces compared to other deposition methods. In this work, NdFeB coatings were deposited on stainless steel by plasma spraying at various standoff distances. Some of the coatings were also annealed. Surface roughness profiles of as-sprayed and heat-treated coatings were measured by contact profilometry and analyzed via statistical methods. The effect of standoff distance and annealing on roughness is discussed along with the significance of measurement direction and evaluation length.

In this present work, investigators determine how particle temperature, combustion pressure, and heat treatment affect the porosity, oxide content, and tensile properties of warm-sprayed titanium. Coatings were deposited with nitrogen flow rates ranging from 0.5 to 1.5 m 3 /min and combustion pressures of 1 and 4 MPa. Optimal coating properties were found for specimens formed at a nitrogen flow rate of 0.75 m 3 /min and a combustion pressure of 4 MPa. Post-spray heat treatment was found to improve bonding between deposited particles, significantly increasing the strength and ductility of the titanium coatings.