This study deals with the improvement of the wear resistance of aluminum alloys by metal matrix composites (MMCs). The latter were fabricated by implanting high-speed solid particles into the metal surfaces. For that, stainless steel and Fe-based amorphous alloy particles were accelerated to the substrates using high-pressure nitrogen. The effect of multi-particle implantation, particle material properties

A new concept of composite phase ceramic had been proposed for the topcoat of a durable thermal barrier coating (TBC) system which is one of the critical technologies for advanced turbine engines. The composite phase TBCs showed promising performance related benefits over conventional single phase TBCs, including durability, material affordability, thermal stability and low thermal conductivity. The

The effects of coating thickness on the fatigue lives of AISI 1045 steel shaft-bending specimens with WC-10%Co-4%Cr high-velocity oxygen fuel (HVOF) coatings and hard chrome electroplated coatings under cyclic loading conditions are investigated. Residual stress distributions of the HVOF-coated layer and the hard chrome-plated layer were measured. During cyclic fatigue testing, cracks are initiated

Compared with ceramic materials, the fabrication of dense metal films requires higher impact velocity in vacuum cold spraying (VCS), also known as aerosol deposition method. In this study, a supersonic nozzle for the fabrication of dense, thin and narrow copper lines was designed. The acceleration behavior of gas and copper particles was investigated through CFD numerical simulation. And the impact

(Pb0.89La0.11)(Zr0.70Ti0.30)O3 (PLZT 11/70/30) relaxor ferroelectric (RFE) films were fabricated on Pt/Si substrates by aerosol deposition, which not only enabled the deposition of a film at room temperature but also increased the dielectric breakdown strength. Perovskite phase and microstructural analyses were carried out by x-ray diffraction and scanning electron microscopy techniques. A PLZT 11/70/30

In multilayer coatings, the bonding mechanisms between the different layers determine the cohesive strength of the coatings, which in turn to a large extent controls the mechanical properties of coatings under different loading conditions. In this study, the interfacial bonding state and adhesive strength of a plasma-sprayed single-layer coating (Al2O3), a double-layer coating (Al2O3/BaTiO3), and a

As the demand for flexible devices has increased, polymers have become very promising materials for these applications because they have excellent flexibility, lightweight, and low cost. Vacuum kinetic spraying can be a good alternative technology for film fabrication on polymers as dense ceramic films can be fabricated even at room temperature without thermal degradation of the polymer substrate.

This study aims at evaluating the effects of surface mechanical attrition treatment (SMAT) on mechanical properties and corrosion resistance of NiCrBSi coatings deposited by high-velocity oxygen-fuel (HVOF) spraying. The as-deposited coating has a typical HVOF-sprayed morphology with unmelted and deformed particles, associated with voids and porosities, whereas after SMAT, the affected zone morphology

Cold spraying was first used for the purpose of preparing nickel-based high-temperature lubrication coatings. High-quality In625-Cr2O3-Ag composite coatings were deposited by a high-pressure cold-spray system, and their tribological properties were evaluated at 20 and 1000 °C by a high-temperature tribometer. The microstructure, composition, and wear mechanisms of the coatings were analyzed by x-ray

Aluminium-polymethyl methacrylate-copper (Al-PMMA-Cu) composite coatings were developed using cored wire arc spraying. The bacteria Bacillus sp. was used to evaluate the antifouling performances of the coatings. The microstructures and antifouling mechanisms of the coatings were investigated and discussed. The results show that the composite coatings presented improved antifouling performances, and

Plasma spraying of fine particles promises uniform microstructure and improved properties for ceramic coatings due to the formation of small splats with reduced residual stress and pore size. Although spraying fine particles is challenging due to the poor rheological properties of particles (e.g., low flowability and agglomeration), the potential improvements to the coatings make it an attractive option

Prior work has demonstrated greater antipathogenic efficacy concerning the nanostructured copper cold spray coatings versus conventional copper cold spray coatings, while both the nanostructured and conventional cold spray coatings maintain greater contact killing/inactivation rates relative to other thermal spray deposition methods. Recent work has more heavily focused upon the nanostructured cold

To eliminate the thermal expansion mismatch and improve the bonding strength between ZrSiO4 coating prepared by supersonic atmospheric plasma spraying and C/C composites, a layer with porous structure was produced on the substrate by a preliminary air oxidation treatment. The morphology and microstructure of the ZrSiO4 coating were characterized by SEM and XRD. The results showed the coating prepared

Cold spray is an effective solid-state process for the fabrication of metal matrix composites where metallic, ceramic, or intermetallic reinforcements are embedded in a metallic matrix. Cold-sprayed metal matrix composites (CS MMCs) enable combining favorable properties of their constituent phases. Combinations of the ductility of metals with the high strength of ceramics or with the creep resistance

A novel self-sealing structure for metal-supported solid oxide fuel cells (MS-SOFCs) is designed by applying brazing technology between the metal support and interconnector to solve the sealing problem on the anode side of planar SOFCs. A high-reliability self-sealing effect is thus realized at the anode side of the MS-SOFC. Plasma spraying technology is used to prepare cell functional layers including

A particular YSZ feedstock for very low-pressure plasma spraying (VLPPS) has been designed which can be automatically divided into less than 5 μm YSZ molten particles in the long plasma jet. Fully molten particles were deposited on the substrate at different deposition distances of 250, 350 and 450 mm, respectively. The deposition behavior of less than 5 μm YSZ molten particles were studied aiming

Titanium alloys have high specific strength and excellent high temperature and corrosion resistance but low hardness and poor wear resistance. In this study, TiC-reinforced Ti2Ni/Ti5Si3 eutectic matrix composite coatings were fabricated on TC21 titanium alloy substrates by laser cladding. The phase composition and microstructure of the coating with micro- or nano-sized SiC addition as well as the microhardness

Ti2AlNb alloys are often used to fabricate high-pressure compressor blades and casings in aircraft engines with high thrust/weight ratios. In this study, a three-layered seal coating, NiCrFeAlBN-YSZ-NiCrAl, was prepared by thermal spraying on a titanium alloy (Ti2AlNb) substrate. The microstructure, surface hardness, and bond strength of coatings as well as their thermal cycling performance and abradability

Diamond-like carbon (DLC) films have a high hardness and a low friction coefficient. Therefore, DLC films are applied in industrial fields to reduce energy consumption. However, DLC films can only be obtained as coatings, and DLC films of only micrometer thickness can be deposited on substrates. In this study, we focused on the cold spray (CS) technique as a means of obtaining a DLC-containing metal

A hybrid analytical heat conduction model was developed to predict the transient thermal evolution at the particle–substrate interface during the deposition of cold spray process. First, three-dimensional heat conduction model based on classical diffusion approach was developed to predict the transient surface temperature of the substrate. To that end, the traveling wave solution technique was utilized

Harvesting waste energy using thermoelectric (TE) principles is a key technology that increases overall power conversion and efficiency from combustion-based energy generation systems. However, design restrictions of commercially available thermoelectric devices and toxicity of commercial thermoelectric materials currently limit large-scale deployment. Additive and multilayered design and manufacturing

In this paper, we examine the correlation between thermal spray process parameters that affect the deposition rate and the residual stress buildup in HVOF metallic and cermet coatings. Parameters of interest including feed-rate, raster speed, and substrate temperature (controlled via external cooling means) were evaluated in the context of their effect on the stress evolution in gas fuel HVOF-sprayed

Different studies have been demonstrated that the surface integrity of substrate bulk materials to be coated has a significant impact on the adhesion of thermally sprayed coatings. It is known that the surface integrity of parts processed by selective laser melting (SLM) differs from those obtained from bulk materials. Although 316L stainless steel is among the most investigated material for SLM, the

This paper examines the residual stresses generated by laser-assisted cold spray deposition of an iron-based oxide dispersion strengthened alloy (Fe91Ni8Zr1 at.%) on an AISI 1018 mild steel substrate, as well as studies of the effect of the laser heating on the substrate alone. The in-plane residual stress values were determined by X-ray diffraction-based measurements. In the top section of the layers

There has been considerable interest in the application of cold gas dynamic spray (CGDS) to deposit nickel-based superalloy coatings for the repair and development of high-value components that operate under extreme environmental conditions. The CGDS process introduces residual stresses in the coating layers, but inherently effects the subsurface of the substrate in a similar manner. The present study

This study investigated the impact behavior of ceramic particles in vacuum kinetic spray (VKS), also known as aerosol deposition method, for successful coating build-up using both experimental methods and numerical simulations. A coating trial and fluid dynamics simulation results showed that there existed a critical impact velocity at which successive coating build-up was possible. This indicated

Residual stress plays an important role in the properties and performance of coatings, such as coating–substrate adhesion. With in situ residual stress measurements, further insight into the coating formation process can also be obtained. Substrate curvature deflection measurements during the aerosol deposition of BaTiO3 were employed to calculate the coating’s residual stress via the Stoney formula

The nature and magnitude of residual stresses in thermal-sprayed coatings determine their lifetime and failure mechanisms. The residual stresses of suspension high-velocity oxy-fuel (SHVOF) thermal sprayed alumina (Al2O3) coating were measured with hole-drilling and x-ray diffraction. The coating is dense and consists of amorphous and two crystalline phases: alpha and gamma. The residual stresses measured

Protective coatings based on an Al-Al2O3 metal matrix composite (MMC) were sprayed using dynamic metallization (DM), a low-pressure cold spray variant. A series of samples approximately 1 mm in thickness were sprayed using different spray process parameters (temperature, velocity) and different feedstock powder compositions (Al, Zn, Al2O3). This resulted in MMCs of different phase compositions and

Ceramics coatings produced by atmospheric plasma spraying (APS) on steel alloys parts involve high residual stress level that can affect the coating properties and integrity. Most of the experimental studies were focused on the stress evaluation into APS-produced coatings onto static targets. However, these studies have not been extended to stresses induced on rotating samples. Indeed, the thermal

The tribo-mechanical properties of NiMoAl-Cr2AlC MAX phase composite coatings on stainless steel substrate have been investigated. NiMoAl with different amounts of Cr2AlC (10, 20, 50 and 100 wt.%) were prepared by turbo-mixing and deposited by High-Velocity Oxy-Fuel (HVOF) method on stainless steel substrate. The phase composition, microstructure, chemical composition, tribological and mechanical properties

Shot peening was induced by utilizing the particles that flow out of the nozzle in a WPPA-HVOF process. For investigation of the peening particles, a model was built to simulate the HVOF spraying process including the temperature, velocity, pressure field of the flame, and the reaction of kerosene oxidation. The effect of incident velocity, incident position, and the diameter on the in-flight particle

Thermite materials, which are a pyrotechnic composition of metal and metal oxide, can create bursts of heat and high temperature thanks to an exothermic reduction–oxidation reaction. Fabrication methods of bulk thermite materials should preserve the reactivity of the materials and ensure a sufficient mixing of components. This work investigated the use of kinetic spraying and ball milling to overcome

Inconel 625, Ni-based superalloy has been increasingly used as coatings for protecting metallic surfaces against wear, high temperatures, and corrosive environments. In this paper, the investigation of depositing Inconel 625 of varying coating thicknesses (250, 300, 400, and 500 µm) using high-velocity oxy-fuel technique on 304 stainless steel substrate was conducted. The residual stresses of the as-sprayed

The diamond enhanced (NiCoCrTi0.5Nb0.5)Cx (x = 3, 6, 12 wt.%) high-entropy alloy coatings were well-prepared by laser cladding, which are denoted as C3, C6 and C12, respectively. The macroscopic morphology, phase, microstructure, hardness and wear resistance were investigated. The coatings without pores and cracks, are well-metallurgically bonded with the substrate. The width, melting depth and dilution

Titanium dioxide (TiO2) was plasma sprayed using a high feed-rate spray system with hybrid water–argon stabilization torch (WSP-H). TiO2 powder agglomerated from nanometric particles was used as the feedstock. The produced coating had thickness over 4 mm, to be comparable with bulk ceramic bodies. The deposit was removed from the substrate and annealed in air to reoxidize the oxygen deficient as-sprayed

Two Ti-63.39Al-8.26Nb-0.2Y powders (powder 1 and powder 2) were fabricated by rapid in situ reaction and arc melting, respectively, then deposited on 316L stainless-steel substrate by the high-velocity oxygen fuel (HVOF) process. The phase composition, microstructure, porosity, microhardness, and adhesive strength of the two kinds of coating (DC1 and DC2) were characterized. DC1 had lower porosity

Pure Al coating and Al2O3 particles reinforced Al composite coatings were prepared by arc-spraying. The feedstocks were pure Al wires and Al-based cored wires containing 10, 20, 30 vol.% Al2O3, respectively. The evolutions of microstructure, porosity and microhardness of the coatings with different Al2O3 contents were investigated. Microstructural analysis shows that the addition of Al2O3 particles

Cold spray (CS) has been proven a promising manufacturing process for the MCrAlY coatings deposition. In this study, NiCoCrAlTaY coatings were deposited on single-crystal nickel-based superalloy (CMSX-4) substrates using the CS technique. Nitrogen and moderate spray parameters were used, and the resulting MCrAlY coatings were compared to coatings sprayed using helium under similar spray conditions

In plasma spraying, copious heterogeneous nucleation starts when a molten ceramic droplet spreads on a cold surface under rapid cooling. Some nuclei will survive and grow, eventually forming a splat of grains of distinct crystalline orientations. This paper aims to predict the dynamic process of yttria-stabilized zirconia (YSZ) droplet impact with solidification microstructure formation under various

Polymer coating by cold spray presents interesting features such as the possibility of protecting metallic substrates or adding functionalities to a structure. However, it is characterized by a low deposition efficiency and a weak interface between the substrate and the coating. In this study, we performed fluoropolymer coatings by the cold-spray process. Analysis of the particle deposition during

The formation of thermally grown oxide (TGO), which is composed of alumina and mixed oxides, leads to the delamination of thermal barrier coating (TBC). In this study, to improve the oxidation resistance and adhesion strength of TBCs, grinding and grit-blasting treatments with alumina grits were applied to the surface of the bond-coat (BC) before deposition of the top-coat (TC). These treatments are

The level of residual stresses is of great importance for many applications. In this work, the two established residual stress analysis methods x-ray stress analysis and incremental hole-drilling combined with electronic speckle pattern interferometry are compared. Each stress analysis method has its specific limitations. Furthermore, the residual stress state of a material is influenced by its processing

The cascaded-anode plasma torch makes it possible to get a longer and more stable plasma jet with higher specific enthalpy than conventional plasma torches. It is now used widely, but there are still few models of the cascaded-anode plasma torch. This study developed a 3-D time-dependent model that couples the gas phase and electrodes by encompassing the electromagnetic and heat equations both in the

A careful substrate preparation and the physical properties of the coating particles are decisive for the quality and envisaged properties of the deposited layer. Temperature, size, rate and velocity represent the classical quantities, which can be measured in situ using various diagnostics. Nonetheless, another quality-determining parameter is the degree of oxidation which could not be measured in

Sn-based Babbitt coatings are widely used for sliding in hydrodynamic bearings. The Babbitting of bearing surfaces is among others accomplished by casting; however, this implies some disadvantages such as segregations, or susceptibility to shrinkage defects. Thermal spraying represents a promising method to overcome these challenges. To date, no studies on Babbitt coatings deposited by means of low-pressure

The shear fatigue delamination strength of some porous thermal barrier coatings (TBCs) has been evaluated using the torsion pin-test method. The porosities of the tested TBCs were 0-5, 5-10, 15-20 and 25-35%. The shear delamination strength of the TBCs was evaluated and the shear fatigue delamination strength (S–N) curves were obtained under cyclic torsional loading. The Young’s modulus of the TBCs

High-entropy alloys (HEAs) are a new generation of materials that exhibit unique characteristics and properties, and are demonstrating potential in the form of thermal spray coatings for demanding environments. The use of HEAs as feedstock for coating processes has advanced due to reports of their exceptional properties in both bulk and coating forms. Emerging reports of thermal sprayed HEA coatings

Cold-spray additive manufacturing (CSAM) builds strong, dense metal parts from powder feedstock without melting and offers potential advantages over alternatives such as casting, liquid phase sintering, laser or e-beam melting or welding. Considerable effort is required to relieve residual stresses that arise from melt/freeze cycling in these methods. While CSAM does not involve melting, it imposes

Yttria-stabilized zirconia (YSZ) thermal barrier coatings (TBCs) were prepared by atmospheric plasma spraying (APS). SEM–EBSD–Raman spectroscopy evaluated the relationship between the crystallinity, stresses, and cracks in YSZ coatings. Cracks were more likely to form in locations having poor crystallinity, due to the tensile stresses. Analysis between the formation of cracks and stresses shows that

Cold spray has been developed recently to be used as an additive manufacturing technology in order to fabricate bulk components. Residual stresses are known to build up in coatings made by cold spray; therefore, cold spray additive manufacturing (CSAM) is also expected to generate residual stress in bulk parts and components, and that residual stress can lead to shape distortions or component cracking

In cold spray, high gas temperatures and high velocity impact of particles introduce complex thermal and stress histories in the coating layers and the substrate. It is crucial to understand the interplay between temperature evolution and residual stress development as the residual stresses could potentially cause distortion and/or delamination. In this study, a system-level cold-spray deposition model

High-velocity oxygen fuel coatings were produced using gas-atomized Al62.5Cu25Fe12.5 and Al67Cu20Fe5Cr8 powders onto a ferritic stainless-steel substrate, resulting in two similar microstructures, consisting mainly of quasicrystalline phases. The goal of this work was to evaluate the performance of the quasicrystalline coatings under standard wear and corrosion tests. The samples were characterized

Cavitation erosion is a huge problem in engineering structures working under hydrodynamic conditions. The synergistic effect of erosion and corrosion can aggravate the material removal by several orders of magnitude. Surface coatings are widely used to address material degradation by erosion–corrosion. However, non-homogenous microstructure and presence of defects leads to premature coating failure

AbstractTernary energetic structural material (ESM) Ni–Al–CuO was prepared by cold spraying, and its mechanical properties studied under quasi-static-state and dynamic compression conditions. Energy release characteristics including the ignition temperature, energy release, and combustion wave velocity were characterized in both the thermal explosion and self-propagating combustion modes. The results

Suspension plasma spray (SPS) is going through a transition phase from research and development to daily use on production lines. Improving repeatability and reproducibility of coating elements and parameters makes SPS a replacement of former well-developed processes. This transition can be achieved by using in-flight particles diagnostic systems to monitor and control key parameters that influence

Gas turbine efficiency can be improved by increasing the operating temperature and by reducing the need for cooling air, both of which are enabled by higher temperature materials. Silicon carbide based ceramic matrix composites (CMCs) have shown promise for achieving higher temperatures. However, to survive in the high-temperature high-humidity combustion environment, environmental barrier coatings

Both tensile and shear adhesion strength tests were performed to evaluate interfacial strength between hydroxyapatite coatings on titanium alloy substrates subjected to anodization and heat treatment prior to deposition as well as post-deposition heat treatment. Results of the tensile adhesion strength tests were influenced by the size of the blasting media and the processing of pre- and post-heat

Thermal spray processes have been developing toward lower particle temperature and higher velocity. Latest generation high-velocity oxygen-fuel (HVOF) and high-velocity air-fuel (HVAF) can produce very dense coating structures due to the higher kinetic energy typical for these thermal spray processes. Thermally sprayed coatings usually contain residual stresses, which are formed by a superposition