Addition Of Ceramic Particles Research Articles

Microstructure control of ultra-high-strength AlZnMgCu alloys fabricated by wire arc directed energy deposition: the role of variable polarity electric pulse

ABSTRACT In the manufacturing of large-scale ultra-high strength AlZnMgCu alloy components, wire arc directed energy deposition can be an efficient and flexible candidate. However, the fabricated AlZnMgCu alloys are faced with problems like coarse microstructures and high sensitivity to defects. Although metallurgical methods like micro-alloying and ceramic particle addition have shown considerable effects in microstructural control, pure process control methods that don’t affect the composition still lack investigation. This work proposed an effective control method by simply adding electric pulses during manufacturing. Results show that the application of pulses significantly reduces pore defects. A 2 Hz pulse can reduce the porosity by 65.7% to 0.122%. Low-frequency pulses effectively promote grain refinements. At 2 Hz, the deposited metal exhibited a mix of short columnar and fine equiaxed grains with a near-random orientation. Applying electric pulses leads to at least a 4.8% increase in UTS and a 225.0% increase in elongation.

Microstructure evolution from homogeneous as-cast state to annealed heterogeneous structure and mechanical properties of Al-Zn-Mg-Cu alloys with trace TiB2 particles

Materials with a final heterogeneous structure (HS) possess an excellent combination of strength and ductility. However, fine and homogeneous grains are desired in as-cast ingots to avoid defects. The evolution from an as-cast homogeneous microstructure to a pronounced HS owing to the trace addition of TiB2 particles was studied in Al-Zn-Mg-Cu alloys with traditional thermomechanical treatment. It is revealed that the triple junctions and over 2 μm precipitates co-located with TiB2 enhance the particle-stimulated nucleation of recrystallization. The dislocation density difference between the recrystallized and recovered grains is further enhanced by cold rolling. A pronounced HS with alternating soft and hard domains accompanied by multimodal precipitates is modulated, realizing a synergy of yield strength as 632.4 MPa and elongation as 8.8%. It is confirmed that the HS, rather than precipitates, is the primary source of geometrically necessary dislocations (GNDs), leading to the synergy of strength and ductility. Atomistic simulations on the deformation behavior of HS were used to elucidate the strain partition and role of GNDs on mechanical properties. Our results provide a convenient route to fabricate heterogeneous Al-Zn-Mg-Cu alloy by trace addition of ceramic particles in ingots casting instead of elaborated controlling of deformation processing.

The structural and mechanical properties of open-cell aluminum foams: Dependency on porosity, pore size, and ceramic particle addition

Aluminum foams are desired for lightweight, high-performance, and cost-effective materials, particularly in automotive, aerospace, and advanced power plants. Expansion of their applications depends on developing a detailed understanding of the structural and mechanical properties of aluminum foams. In this research, open-cell aluminum foams with 25.51–81.88 % porosity were manufactured through powder metallurgy using a space holder technique, with varying carbamide (urea) ratios (17–80 %) and particle sizes (1–1.4 mm, 1.7–2 mm, 2–2.4 mm). Three different ceramic particles, B4C, Al2O3, and SiC were used as reinforcement to improve the compression properties and energy absorption capacity of the foam materials. The study determined open and closed porosity ratios, spherical diameter, sphericity values, micropore sizes, mechanical properties, and energy absorption capacity of the foam samples both with and without ceramic additives. The results show that porosity ratio, pore size, and ceramic particle addition significantly affect aluminum foams' structural and mechanical properties, allowing for tailored properties for specific applications. It was observed that as porosity increased, compressive stress decreased, and the length of the plateau region and the shape change where densification began increased. However, there was no significant change in compressive stress and specific energy values with changing pore size. The optimal B4C addition was found to be 4 %, which significantly improved compressive strength to 3.75 MPa and specific energy to 4.24 MJ m−3.

Fabrication of high-performance biomedical rare-earth magnesium alloy-based WE43/hydroxyapatite composites through multi-pass friction stir processing

Magnesium-based composites with bioactive ceramic particles addition are promising materials for biomedical implant applications. Nevertheless, the agglomeration of bioactive ceramic particles remains a challenge for fabricating high-performance biomedical magnesium-based composites. Herein, a novel high-performance biomedical rare-earth magnesium alloy-based WE43/hydroxyapatite (HA) composite is successfully fabricated via multi-pass friction stir processing (MP-FSP). Systematic investigations reveal that MP-FSP leads to a uniform distribution of HA particles and efficient elimination of defects. The microstructural analysis shows a significant grain refinement in the WE43 alloy from 49.4 μm to 2.4 μm under triple-passes FSP. The mechanical properties of the composite are enhanced significantly under triple-passes FSP, with yield strength, ultimate tensile strength, and elongation reaching 236.2 MPa, 278.6 MPa, and 14.2% respectively. Corrosion resistance is also improved, with a 30% reduction in the corrosion rate in SBF solution compared to the unprocessed alloy. Moreover, the MP-FSP fabricated composites exhibit superior corrosion-wear resistance, characterized by slight abrasive wear compared to the abrasive wear and severe pitting corrosion observed in the base WE43 alloy. These improvements are attributed to the synergistic effects of grain refinement, dispersion strengthening, enhanced interfacial bonding, and texture modification. Overall, these findings provide significant quantitative insights into the advanced fabrication techniques of magnesium-based composites for biomedical implant applications, highlighting the effectiveness of MP-FSP in enhancing both mechanical and corrosion-related properties.

A novel negative thermal expansion ceramic network interlayer for releasing high residual stress of Cf/SiC heterogeneous brazed joint

Negative thermal expansion (NTE) ceramics have been widely concerned in adjusting the coefficient of thermal expansion (CTE) to release the high residual stress of heterogeneous joint. However, one major problem that needs to be solved is the agglomeration problem caused by excessive ceramic particles addition. In this work, a novel NTE ceramic Sc2W3O12 network interlayer is prepared by the polyurethane template method. The Sc2W3O12 network interlayer with a single NTE phase presents a three-dimensional network structure. The NTE Sc2W3O12 ceramic is uniformly distributed in brazing seam without agglomeration with the help of unique network structure. The active Ti elements play an important role in the interface bonding, reacted with Sc2W3O12 network interlayer and Cf/SiC composites to form Cu3Ti3O and TiC/Ti5Si3 reaction layer, respectively. After introducing Sc2W3O12 network interlayer, the CTE of the composite filler is reduced from 16.6 × 10−6 K−1 to 11.9 × 10−6 K−1, a decrease of 29 %. The highest shear strength of the Cf/SiC heterogeneous joint is reached 130 MPa, which is 5.4 times than that without Sc2W3O12 network interlayer.

Anti-corrosion superhydrophobic micro-GF/micro-TiB2/nano-SiO2 based coating with braid strengthening structure fabricated by a single-step spray deposition

Superhydrophobic surfaces with self-cleaning, anti-biofouling and corrosion resistance merits are attractive for applications in major engineering fields. Generally, these surfaces possess low-surface-energy chemistry and micro- or nanoscale surface roughness. However, rough surfaces are fragile and highly susceptible to abrasion for high local pressures under mechanical load, causing loss of superhydrophobicity. In this study, we proposed a "fiber weaving/hard particles embedding-soft membrane" strategy to construct a kind of organic-inorganic composite coating by embedding micro-glass fiber (GF)/micro-TiB2/nano-SiO2 particles into the polydimethylsiloxane (PDMS)@polyurethane (PU) for fabricating robust superhydrophobic coating. The addition of micro-nano ceramic particles plays two roles including "hard" micro-skeletons to overcome vulnerable issue of "soft" organic membrane and creation of wear-resistant bearing points on the surface. Furthermore, "soft" membrane can absorb stress when subjected to external mechanical force and PU serves as an adhesive to improve interfacial bond strength. Additionally, GF intersperses in the coating, providing anchoring effect and PDMS serves as a modifier to decrease surface energy. Consequently, the proposed hybrid coating could simultaneously augment its mechanical robustness and multifunctional performance, breaking the notorious "trade-off" restriction of superhydrophobic coating. The preparation parameters and operation condition on the performance of the coating were investigated systematacially. The optimized superhydrophobic coating exhibits the highest water contact angle (WCA) of 167.3° ± 3.9°, the lowest sliding angle (SA) of 4.6° ± 1.3°, corrosion protection efficiency of 95.7 % in 3.5 wt% NaCl solution, with exceptional self-cleaning, anti-pollution, adaptability to various substrates, thermostable, anti-icing and mechanical stability properties, among the top-tier multifunctional performance. The inherent properties of micro-glass fiber, micro-TiB2 and nano-SiO2 ceramics and their highly ordered arrangement in the superhydrophobic coating are expected to provide an effective and versatile design proposal for potential applications in corrosion protection.

Effect of powder feeding rate and size on critical velocity and mechanical properties of cold sprayed Al2O3/2024 deposit

The particle acceleration behavior and deposition mechanism of cold spraying aluminum matrix composites (Al2O3/2024) are complicated by the addition of ceramic particles. The effects of different feeding rates and particle diameters on critical velocity and mechanical properties were studied by numerical simulation and experiment. The results indicate that as the powder feeding rate increases, the impact velocity of gas and particles gradually decreases, and the temperature of gas and particles increases, resulting in an increase in the difference between particle impact velocity and critical velocity. The highest tensile strength of the deposit is achieved at a powder feeding rate of 1 r/min, which is 343 MPa. As the powder feeding rate increases, the performance of the deposits decreases, but it significantly saves time and cost. As the particle diameter increases, the impact temperature first increases and then decreases, resulting in the critical velocity first decreasing and then increasing, and the mechanical performance first increasing and then decreasing. To some extent, the best performance of the deposit is achieved when the size of the metal particle is close to that of the ceramic particle.

Tribological performance of ZrO2 nanoparticles as friction and wear reduction additives in aviation lubricant

Abstract High-performance aircraft engines require superior aviation oils to enhance their lubricating performance and prolong service life. Addition of nano-sized ceramic particles has been considered as a useful way to improve the tribological performance of base fluids. Up to now, few previous studies focused on the tribological properties of ZrO2 nanoparticles in aviation oil. The current study dispersed ZrO2 nanoparticles into PAO20 aviation base oil as lubricant additives. A dual-step method comprised of physical blending and ultrasonic dispersing was applied in the preparation of ZrO2 nanofluids. Oleic acid was utilized as surfactant to enhance the stability of ZrO2 nanofluids. Ball-on-plate reciprocating sliding wear tests were conducted to obtain the coefficient of friction and wear volumes. It was found that the PAO20 base oil produced the highest coefficient of friction of 0.278 and wear volumes of 2.305╳10-2 mm3. 5wt% ZrO2 nanofluids with 5wt% oleic acid showed the best lubricating performance. The coefficient of friction was reduced by 31.29%, and wear volume was reduced by 42.95%. In the examination of wear tracks, a physically embedded tribo-layer of ZrO2 nanoparticles and an oleic acid tribo-film with low shearing resistance were formed, which lowered the friction, and protected the mating surfaces against abrasive and adhesive wear. The results obtained in this study have applicable values in the development of high-performance aviation lubricants.

Enhancing mechanical and microstructural properties of Pb composite anode by the addition of W-Co3O4 ceramic particles fabricated by Accumulative Roll Bonding

In this research, the accumulative roll bonding (ARB) technique was employed as a severe plastic deformation method to manufacture a unique bi-metal Pb/W composite reinforced by Co3O4 ceramic oxide. For this purpose, composites with different amounts of reinforcement particles (0.25, 0.5, 1, 1.5, and 2 wt%) were successfully produced using the ARB process (up to 10 cycles). Also, the mechanical properties were evaluated using microhardness, tensile, and shear punch tests. For microstructural investigations, the X-ray diffraction method (XRD), transmission electron microscopy (TEM), and fractography analysis by scanning electron microscopy (SEM) were employed. The Pb-0.5%W/Co3O4 following 10 ARB cycles exhibited optimal mechanical and microstructural properties. For this composite, the tensile strength showed a markable increase of 2.17 times, yield strength by 4.7 times, shear strength by 3.6 times, and hardness by 4.2 times compared to the pure Pb sample subjected to the same ARB cycles. However, the strain was reduced by 3.85 times. These enhanced properties are also followed by increased stiffness and improved anode dimensional stability, creep resistance, and operational lifespan.

Effect of SiC dominated with ZrB2 particles on the ablation and mechanical properties of carbon/novolac‐epoxy (EPN1180) composite at 3000°C

AbstractThis study investigates the mechanical properties and erosion resistance of high temperature–pressure carbon‐epoxy novolac insulation reinforced with ZrB2/SiC particles. For this reason, at first, five samples were fabricated using the hot press, which included resin epoxy novolac EPN1180 base without reinforcement and four samples containing resin with 20:80, 30:70, 40:60, and 50:50 of SiC: ZrB2 particles respectively. After manufacturing of the samples, the mechanical properties were evaluated through bending and tensile testing, followed by erosion resistance properties by the use of oxyacetylene flame erosion tests. Chemical composition and surface morphology analysis of the composites were conducted using energy‐dispersive spectroscopy, scanning electron microscopy, and x‐ray diffraction analysis. Results indicate that the addition of ceramic particles enhances both mechanical properties and erosion resistance of the composite. The pure resin sample exhibited the highest weight loss and thickness reduction, while the sample containing 40% SiC and 60% ZrB2 demonstrated the least weight loss and thickness reduction about 55% and 83% respectively compared to pure sample. Additionally, the sample with 30% SiC and 70% ZrB2 had the lowest backside temperature. Furthermore, the sample with 20% SiC and 80% ZrB2 exhibited the highest mechanical properties, with a tensile strength of 422.5 MPa and flexural strength of 587.11 MPa. Morphological analysis revealed the presence of phases such as SiO2, ZrO2, and ZrSiO4 attributable to the ZrB2/SiC particles, contributing to the enhancement of erosion resistance.Highlights Examines volume ratios of ZrB2/SiC. Discovers the best particle ratio (20%SiC, 80%ZrB2) for mechanical properties. Identifies the best particle ratio (30% SiC, 70% ZrB2) for erosion resistance. Reveals key phases enhancing erosion resistance with advanced analysis methods. Linear and mass ablation rate improved by 83% and 55% (best formation).

Corrosion behaviour of SiC particulate reinforced AZ31 magnesium matrix composite in 3.5 % NaCl with and without heat treatment

Magnesium is a lightweight structural material widely utilised in automotive applications. To enhance its mechanical properties, ceramic particulate reinforcement can be incorporated, particularly for wear resistance and high-temperature applications. However, the addition of ceramic particles to magnesium can compromise its corrosion resistance due to microgalvanic cell formation at the interfaces between the Mg matrix and the second phase. This reduces the chemical protection provided by the passive film. In this study, the corrosion properties of AZ31 and AZ31-5SiC samples were investigated, with a focus on the effect of heat treatment. Detailed microstructural and electrochemical analyses revealed that the AZ31 cast sample forms an effective passive film, resulting in improved corrosion resistance. However, the addition of SiC particles to AZ31 increased the corrosion rate, with corrosion mechanisms evolving over time. To mitigate these effects, a heat treatment process was employed to dissolve β-Mg17Al12 eutectic and Al8Mn5 intermetallic phases. The heat-treated AZ31 with SiC exhibited an improvement in corrosion resistance. These findings highlight the potential for heat treatment to enhance their corrosion resistance, thereby broadening their application prospects.

Oxide/metal interface enhancement for improved dispersion strengthening mechanism in oxide-strengthened tungsten

The addition of secondary ceramic particles has shown to be effective in enhancing the mechanical properties of tungsten alloys. The diverse strengthening effects observed with various secondary particles necessitate further investigation. Herein, three ultrafine-grained, oxide-dispersed-strengthened tungsten alloys were prepared using solution combustion synthesis combined with low-temperature sintering. We thoroughly investigated the influence of Al2O3, La2O3, and Y2O3 on the microstructure and mechanical properties of tungsten, as well as their respective strengthening mechanisms. A detailed comparison revealed discrepancies between the yield strength experimentally measured and the theoretically predicted strength based on conventional grain refinement strengthening and dispersion strengthening theories, highlighting the significance of the intrinsic nature of dispersed oxides. Electron microscopy analysis and density functional theory calculations revealed that, compared to other oxides, the heterogeneous interface of Al2O3 with W exhibited minimal lattice distortion and the highest work of separation, resulting in a robust interface bonding. The prepared W–Al2O3 alloy showed exceptional performance with Vickers hardness HV0.2 of 698.9 and yield strength of 2488 MPa. Its yield strength surpassed that of W–Y2O3 and W–La2O3 alloys, as well as other commonly reported refractory metal materials.

Piezoelectric properties of PVDF‐TrFE/BaTiO3 composite foams with different contents of TrFE units

AbstractPiezoelectric (PE) materials play an important role in the emerging field of micro and wearable electronics. Achieving high PE response is a key feature for their use in energy harvesting and sensing systems. In this study, highly porous lightweight composite foams composed of PVDF‐TrFE (70/30 and 80/20 mol%) and different BaTiO3 content (5, 10, and 20 wt%) are prepared by thermally induced phase separation method. The PE foams were structurally and thermally examined by using Fourier‐transform infrared spectroscopy, x‐ray diffraction, differential scanning calorimetry, and thermogravimetric analysis analyses. All composite foams were characterized by high β‐phase content, while the addition of ceramic particles resulted in higher crystallinity and thermal stability of the investigated foams. Two distinct poling methods were employed due to the different molar compositions of the copolymers. The PE response was measured by the PE strain coefficient (d33) and the output current (Ip). The composite foams based on PVDF‐TrFE 70/30 mol% copolymer, having two well‐separated Curie temperatures for the organic and inorganic phases, can be polarized to achieve the contribution of both components to the PE performance, reaching the highest value of −28.3 pC N−1 and 130 nA at 10 Hz for the composite with 20 wt% BaTiO3.

Prediction and Experimental Evaluation of Mechanical Properties of SiC-Reinforced Ti-4.25Al-2V Matrix Composites Produced by Laser Direct Energy Deposition.

An important direction in the development of additive technologies is associated with the addition of ceramic particles (oxide, carbide, boride, and nitride ceramics) to metal powders. The prediction of the physical and mechanical characteristics of SiC-particle-reinforced composite materials (PRCMs) in comparison with experimental results was studied. A near-α Ti-4.25Al-2V titanium-alloy-based composite reinforced by 1 vol.% of SiC ceramic particles was produced using laser direct energy deposition. A multiscale modeling approach at the micro and macro levels was applied. At the micro level, the toughness and strength characteristics for a temperature interval of T = 20-450 °C were predicted using a representative volume element of PRCM with the nearly real shape of SiC particles. At the macro level, the features of plastic deformation and fracture of the PRCM were predicted by numerical modeling using the commercial software Digimat Student Edition ver. 2022.4 and Ansys Student 2023 R2. The addition of SiC particles was found to improve the physical and mechanical properties in the whole temperature range. The results of the numerical modeling were consistent with the experimental data (the deviation did not exceed 10%). The proposed approach for predicting the physical and mechanical properties of Ti-4.25Al-2V/SiC can also be used for other PRCMs obtained by laser direct energy deposition.

The influence of ZrO2 on tribological and mechanical characteristics of Al composite

Metal matrix composites based on aluminium alloys are emerging for industrial applications where a high strength to weight ratio is required. In this work, a reinforced composite made of an aluminiumalloy matrix grade 7010 with zirconium dioxide is developed. Utilizing the stir casting technique, zirconium dioxide is used as reinforcement in composite materials at weight percentages of 2 percent, 4 percent and 6 percent. The composite's mechanical and metallurgical characteristics are examined. SEM and EDS image demonstrating the homogeneous dispersion of the particles inside the matrix alloy. Ceramic particle addition increases material hardness by limiting alloy matrix dislocation. Tensile tests show that adding zirconium dioxide particles increases the material's strength. The Al7010/6% zirconium dioxide composite's ultimate strength (UTS) was 255 MPa, 26% higher than the Al7010 alloy's UTS, and the Brinell hardness of Al7010/6% is 93 BHN, which is 46% higher than the base alloy. Using a pin-on-disc wear testing system, the dry sliding wear behaviour of the Al7010/2 to 6 wt% zirconium dioxide composite is studied at ambient temperature. The prepared samples wear behaviour was evaluated under various weights and speeds. Compared to the base matrix alloy Al7010, the composites showed greater wear resistance.

Compression behaviour and strengthening mechanisms for Cu hybrid composites

ABSTRACT In this investigation, Cu-TiO2-Graphite hybrid composites were fabricated with variations in wt.% of TiO2 and fixed wt.% of Graphite contents through stir casting technique. The size of the grains measured after casting were 83 ± 04, 64 ± 10, 41 ± 10 and 29 ± 04 μm for 0, 3, 6, and 9 wt% hybrid composites, respectively. The addition of 1 wt.% graphite (Gr) was not only to enhance the mechanical and tribological properties but also to improve the wettability during casting. The influence of TiO2 and Gr in Cu-hybrid composite on compression test was investigated followed by characterisation studies involving XRD, EDS, TEM, EBSD. The results reveal that 9 wt% reinforced composite exhibits more strain hardening. Further, composite exhibits higher strength due to the presence of combined strengthening mechanisms such as grain boundary, Orowan and thermal expansion coefficient mismatch in commensurate with ceramic particle addition. Out of these, it is found that Orowan strengthening contributes significantly to the compression strength of the hybrid system investigated.

Microstructure and mechanical properties of SiC-reinforced Inconel 718 composites fabricated by laser cladding

Laser cladding provides the feasibility for fabricating various ceramic-reinforced metal-matrix composite coatings, where the reinforcement content plays a critical role in influencing the residual stresses and the performance of the cladded layer. In this paper, the SiC-reinforced Inconel 718 composites are prepared by LC, and the microstructure and mechanical properties (stress distribution, microhardness, wear behavior) of the cladded layers with different SiC contents are investigated. Based on multi-physics modeling complemented by experimental validation, the thermal stress distribution is analyzed and the residual stresses of the formed Inconel 718/SiC are investigated. The addition of an appropriate amount of SiC can help to relieve residual stresses in the clad layer, with the layer containing 5 wt% SiC corresponding to the minimum residual stress. Moreover, the addition of ceramic particles is conduced to refine the microstructures, and metallic carbides generated by the decomposition of SiC in combination with the diffused elements of the matrix play a positive role in the hardness improvement. The wear resistance of the coatings also increases significantly with increase of SiC content, and the wear mechanism is dominated by abrasive wear, accompanied by oxidation wear, fatigue wear and adhesive wear.

Microstructure evolution and mechanical properties of TiB2/18Ni300 composite material produced by laser additive manufacturing

As a reinforcing phase, TiB2 exhibits exceptional wettability and stability when mixed with steel matrices, making it an ideal reinforcement for steel matrix composites. In this paper, we add TiB2 for additive manufacturing of 18Ni300 steel for weight reduction and reinforcement. TiB2 reinforced 18Ni300 matrix composites were prepared by laser cladding. SEM, EDS, and XRD were used to observe the joints' interface and fracture characteristics and analyse the substance composition. Tissue analysis was then performed using EBSD and TEM. According to the TEM and XRD results, there is a martensite structure within the cell, and the cell boundary is an austenite structure. After adding TiB2, a reinforcing phase ((Mo, Fe)3B2) is distributed at the boundary of the cell structure. The high hardness of boride increases the microhardness of the composite material. The yield strength, modulus, and elongation of the samples prepared with 18Ni300 powder are lower than that of forged 18Ni300, but the tensile strength reaches 1134 MPa. The addition of TiB2 increases the composite material's yield strength and elastic modulus significantly. This strengthening technique, which employs the addition of ceramic particles to martensitic steel, is currently not widely used. This experiment provides a theoretical basis and process reference for preparing high-stiffness and lightweight ceramic particle reinforced metal matrix composites.

Incorporation of Al2O3 and ZrO2 ceramics to AZ31 magnesium alloys composite coating using micro-arc oxidation method

In this research, a composite coating with Al2O3 and ZrO2 particles have been applied on AZ31 magnesium alloy by micro-arc oxidation (MAO) technique. The alkaline electrolyte included a constant based composition and different composition of the Al2O3 and ZrO2 additives. Microstructure observations reveal that the surface pores of composite coating reduced during addition of ZrO2 and Al2O3 ceramic particles. The hardness of coating increased from about 380 for non-added to 620 MPa for Al2O3+ZrO2 added coating and wear rate reduced about 8 times. Wettability of the coating increased by incorporation of Al2O3 and/or ZrO2 particles while, Al2O3 is more effective than ZrO2. Addition of the ceramic particles enhanced the hydrophilicity properties of surface in wettability test and a contact angle of 43° was obtained for coating including Al2O3+ZrO2. The antibacterial properties of MAO coatings showed that S. aureus bacterium is more sensitive to the zirconia and alumina particle than S. typhimurium bacterium after 24 h of incubation.

Highly corrosion and wear-resistant NiW–SiC–CeO2 composite coating

ABSTRACT Crack-free and uniform NiW composite coatings filled with ceramic particles such as SiC and CeO2 were deposited on brass substrates by applying direct current (DC) and a well-designed pulse reverse current waveforms (PRC). PRC coatings displayed the noblest corrosion potential and lowest current density compared to DC electrodeposited coatings. Among all PRC coatings, PRC–NiW–SiC–CeO2 demonstrated the highest corrosion resistance and the lowest current density. It also seems that the addition of ceramic particles to the NiW matrix enhanced the wear resistance of the coatings and the lowest wear volume of about (14.119 × 103 µm3) and the friction coefficient of 0.25 was obtained due to the formation of the uniform, void-free and packed structures with high content of SiC and CeO2 particles in the deposit.