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In order to investigate the acceleration and deformation behavior of particles during cold spraying, the finite element method was used to simulate the acceleration process of copper particles with different sizes inside the Laval spray gun, and the accuracy of the simulation results was verified through particle image velocimetry. Meanwhile, the multi-particle collision model was established using a coupled Eulerian-Lagrangian method with Python script to simulate the deposition process of copper particles and analyze the residual stresses of the copper coating. The simulation results of particle acceleration indicated that the velocity of the same material increased as the particles size decreased under the same spraying conditions. The simulated particle velocity distribution closely matched the actual velocity distribution during spraying, with only a 3.5% difference in average values. Under the conditions of 3 MPa and 723 K, the collision process of particles at different moments was simulated, and the deposited particles were compacted by subsequent particles, causing severe deformation and filling of the pores between the deposited particles, forming a dense coating. The residual stress of the coating simulated by the multi particle collision model(-57.02 MPa) was close to the measured value(-42.68 MPa), demonstrating that this model could effectively reflect the formation of the coating and the distribution of internal residual stresses.

Rubber tire mold fouling is a severe problem leading to mold surface corrosion, tire defects, and extra energy consumption. Traditional mechanical and chemical cleaning is inefficient and induces mold surface damage. Low surface energy organic coating displays antiadhesive behavior but is susceptible to wear. Here, we develop a bioinspired Co-CeO2/MoS2 coating with effective mechanical robustness, corrosion resistance, and antifouling behavior by leveraging a slippery liquid-infused surface (SLIPS) strategy. The micro-nanostructure of the coating serves as mechanical stability and anticorrosion skeleton with the infused lubricant acting as a slippery antifouling surface. The variation of microstructure, mechanical strength, corrosion resistance, and antifouling behavior of the coating with individual and synergistic addition of CeO2 and MoS2 is systematically characterized. The slippery Co-CeO2/MoS2 coating shows excellent mechanical stiffness, corrosion resistance, and antifouling performances in rubber vulcanization conditions. [ABSTRACT FROM AUTHOR]

Developing ecofriendly anticorrosion coating has great demand for marine protection. Incorporation of nontoxic inorganic fillers into waterborne epoxy (WEP) coating shows tremendous potential for enhancing corrosion resistance. However, the application of MXene/WEP coating is limited by the poor dispersion of MXene in WEP and insufficient corrosion resistance. Herein, a polydopamine (PDA) modified MXene‐CeO2@PDA (MCP) filler is constructed by a combination of CeO2 with MXene and embedded into WEP to form ecofriendly anticorrosion MCP/WEP coating. Dispersion of MXene in WEP is improved by the introduction of CeO2 and PDA modification. Benefiting from the synergy of the physical labyrinth effect of MXene and the chemical inhibition effect of CeO2, MCP/WEP coating exhibits remarkable anticorrosion behavior in 3.5 wt% NaCl solution with a low corrosion rate (CR) of 4.48 × 10−6 mpy, which is three orders of magnitude lower than that of blank WEP (4.78 × 10−3 mpy). Moreover, MCP/WEP presents long‐term and stable corrosion protection for over 30 days. The results reveal the incorporation of MCP significantly promotes the anticorrosion performance of WEP. [ABSTRACT FROM AUTHOR]

Developing a coated metal mold to avoid scuff, corrosion, and fouling in rubber vulcanization condition remains challenging. Here, a composite coating is described which combines resistance to fouling, wear, and corrosion by incorporating low surface energy tungsten disulfide (WS2) into a robust cobalt (Co) matrix for wear and corrosion resistance together with antifouling. The dispersity of WS2 in the electroplating solution is improved by combining chemical modification with mechanical milling. The addition of 2 g/L WS2 to the electroplating bath produced a Co-WS2 composite coating with effective tribological and anticorrosion performance in 3.5 wt.% standing NaCl solution at 25 ℃ as well as superior antifouling behavior in rubber vulcanization conducted at 160 ℃ and 9.8 Mpa. [ABSTRACT FROM AUTHOR]

Rubber tires, as an important part of automobiles, are produced by molding operation under molten temperature and high pressure. However, mold fouling during the vulcanization process is a rock-ribbed problem that not only leads to the loss in productivity and degradation of product quality but also results in severe accidents and enormous economic losses. In this work, a promising Co-Mo/CeO2 composite coating was electroplated and investigated to solve the mold fouling problem. The effect of CeO2 content on the surface morphology, microstructure, hardness, tribological and electrochemical behavior is systematically studied. With an addition of 10 g/L CeO2, the Co-Mo/CeO2 composite coating not only possesses the highest microhardness, the best wear and corrosion resistance but also features hydrophobicity and remarkable mold antifouling performance. This study offers a new strategy for producing composite coatings with excellent performance to reduce mold fouling in practical tire industry applications. Co-Mo/CeO2 composite coatings with excellent corrosion and wear resistance as well as low surface energy were simply electrodeposited and applicated for antifouling in tire mold for the first time. [ABSTRACT FROM AUTHOR]

The dispersity of incorporated particles is critical for the creation of composite coatings with enhanced performance. Here, we propose a mechanical agitation and ultrasound-assisted pulse electroplating technique for producing exfoliated MoS2 reinforced cobalt-based composite coatings with improved tribological and electrochemical properties. The dispersity of exfoliated MoS2 and its corresponding effect on the microstructure, microhardness, tribological and electrochemical behaviors of the resultant composite coatings are systematically investigated. The results reveal that the outstanding dispersity of exfoliated MoS2 in electrolyte is beneficial to its even distribution and incorporation in the composite coating, endowing the resultant composite coatings with a smooth surface, compact structure, high hardness, remarkable antiwear and friction reduction performance as well as superior corrosion resistance. This study offers a strategy for producing high-performance composite coatings with promising practical applications. [ABSTRACT FROM AUTHOR]

High-performance coatings with self-lubrication, superior wear, and corrosion resistance are sought after in modern industry. Here we reported a cobalt–nickel/tungsten disulfide (Co-Ni/WS2) composite coating fabricated by a pulse electrodeposition approach. The codeposition of WS2 significantly affects the microstructure, hardness, and tribological and electrochemical behaviors of the Co-Ni/WS2 composite coating. Scanning electron microscopy, X-ray diffraction, and energy dispersive X-ray spectroscopy analyses show that the Co-Ni/WS2 composite coating is characterized by a hierarchical "cactus-like" structure with WS2 embedded and distributed uniformly in the Co-Ni matrix. Tribological and electrochemical tests reveal that the Co-Ni/WS2 composite coating exhibits a low coefficient of friction (COF) and wear rate sliding against a GCr15 steel ball under dry sliding conditions and remarkable corrosion resistance in 5.0 wt% NaOH solution under room temperature and is thus a promising composite coating for practical applications. [ABSTRACT FROM AUTHOR]

In this work, Fe3Al-based composites reinforced with carbon nanotubes were fabricated by a hot-press sintering process under various sintering pressures. The effects of sintering pressure and additives (alumina and lanthanum) on both the physical and the mechanical properties were systematically investigated. Results showed that with the sintering pressure of 15 MPa and incorporation of carbon nanotubes (CNTs), the microhardness of Fe3Al composite exhibited a peak value at 1038.1 HV, which was ~ 60% higher than those without the addition of carbon nanotubes (644.9 HV). Also, both the compressive yield strength and the thermal conductivity of Fe3Al composite were also significantly improved. Results of wear test showed the Fe3Al composite exhibited a low wearing rate (10−6-10−5 order of magnitude) and a friction coefficient (0.53-0.67). [ABSTRACT FROM AUTHOR]

Ceramic particles reinforced copper (Cu) matrix composites with good electrical conductivities, superior mechanical and tribological properties show great prospect in electrical contacts, thermal management and sliding bearing materials. A novel Cu matrix composite with low coefficient of friction (COF) and high wear resistance is rationally designed and prepared by hot-press sintering the core-shell structured Cu/graphene oxide (GO)/Cu composite powders and Cu decorated Ti 3 AlC 2 particles to achieve homogenous dispersion of GO in the Cu matrix and good interfacial bonding of Cu matrix and GO and Ti 3 AlC 2. Its tribological performance and corresponding anti-wear alongside with friction reduction mechanisms at room temperature are systematically investigated. The GO-Ti 3 AlC 2 synergistically enhanced Cu matrix composite exhibits lower COF and wear rate than those composites reinforced with GO or Ti 3 AlC 2 alone , for GO and Ti 3 AlC 2 synergistically bear the load and form continuous, compact and lubricating tribo-layer on the worn surface. [ABSTRACT FROM AUTHOR]