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In this review, we present an extensive summary of research on superhydrophobic electrodeposits reported in the literature over the past decade. As a synthesis technique, electrodeposition is a simple and scalable process to produce non-wetting metal surfaces. There are three main categories of superhydrophobic surfaces made by electrodeposition: (i) electrodeposits that are inherently non-wetting due to hierarchical roughness generated from the process; (ii) electrodeposits with plated surface roughness that are further modified with low surface energy material; (iii) composite electrodeposits with co-deposited inert and hydrophobic particles. A recently developed strategy to improve the durability during the application of superhydrophobic electrodeposits by controlling the microstructure of the metal matrix and the co-deposition of hydrophobic ceramic particles will also be addressed. [ABSTRACT FROM AUTHOR]

Type 304L stainless steel (SS) samples were used to investigate the correlation between carbide precipitation and triple junction structure derived from crystallographic data obtained by the orientation imaging microscopy associated with electron backscattered diffraction. The samples were solution treated and annealed at different sensitization temperatures/time to introduce various degrees of carbide precipitation at the interface region, thus different degrees of selectivity toward triple junctions. Four models were used to characterize triple junction microstructures: (i) the I-line and U-line model, (ii) the coincident axial direction (CAD) model, (iii) the coincident site lattice (CSL)/grain boundary (GB) model and (iv) the plane matching (PM)/GB model. Among them, the I-line and U-line model is the most effective in identifying special triple junctions, i.e., those exhibiting the beneficial property of high resistance to carbide precipitation. The results showed that the percentage of special triple junctions (I-lines) immune to carbide precipitation, increased from 35 to 80%, as the precipitation became more selective toward triple junction structures due to the corresponding sensitization heat treatment conditions, whereas more than 80% of random triple junctions (U-lines) exhibited susceptibility to carbide precipitation regardless of the sensitization conditions. [ABSTRACT FROM AUTHOR]

In this study, a detailed investigation is conducted on cold sprayed copper coatings in their as-deposited state as well as after annealing at 350 °C for 1 h. The local variations of microstructure and hardness are revealed through a combination of electron backscattered diffraction and high-speed nanoindentation mapping techniques. While a highly heterogeneous microstructure is present in the as-deposited material, annealing results in a more uniform grain size, an increase in the fractions of twin and twin-related boundaries and a decrease in the density of geometrically necessary dislocations and low angle grain boundaries. The relative contributions of grain boundary hardening and work hardening are evaluated via hardness line profile analyses. The identification of oxide films along splat-splat interfaces suggests a potential additional factor contributing to local hardness. • Cold sprayed Cu materials for used nuclear fuel containers were studied using EBSD and nanoindentation. • Both microstructural and mechanical heterogeneity decreased after annealing. • The relative contributions of grain boundary hardening and work hardening were evaluated. • Oxide films along the interfaces of adjacent splats were identified. [ABSTRACT FROM AUTHOR]

Copper coatings on steel, manufactured by a novel combination of two different manufacturing technologies, electrodeposition and cold spraying, are employed as a corrosion barrier in the current design of used fuel containers (UFCs) for the long-term storage of Canada's used nuclear fuel. This study examines such copper coatings on a prototype container section, with a particular focus on the interface region where copper materials fabricated by the two processes converge. Distinct microstructures for the electrodeposited and cold sprayed copper layers were observed. An unexpected recrystallized layer on top of electrodeposited copper was identified for the first time. Local annealing at 350 °C and 600 °C for one hour resulted in more homogeneous microstructures and Vickers hardness profiles among the copper layers, which is favorable for this application by reducing processing related heterogeneity in the interface region. More homogenized structures with high fractions of special grain boundaries in this region are expected to provide enhanced mechanical and corrosion properties. • Microstructural analysis was performed on Cu coatings for used fuel containers. • A recrystallized layer between electrodeposited and cold sprayed Cu was identified. • Annealing reduces microstructural and mechanical heterogeneity. • Nanotwinned electrodeposited Cu experiences texture evolution during annealing. [ABSTRACT FROM AUTHOR]

Electrodeposition is considered as a cost-effective fabrication method for metal-diamond heat sink materials. However, the formation of the metal-diamond interface has not been addressed in detail to date although controlling the interfacial microstructures is crucial. In this study, we electrodeposited copper-diamond composite materials and observed that 66 μ m sized diamond particles decreased the thermal conductivity of copper whereas 420 μ m sized diamond particles increased the thermal conductivity. The differential effective medium (DEM) model analysis showed that the thermal boundary conductance values at the electrodeposited copper matrix-diamond interface were 1.3 MW/m2K and 3.1 MW/m2K when the diamond particle sizes were 66 μ m and 420 μ m, respectively. This discrepancy was attributed to the microstructure of the copper matrix in the vicinity of diamond particles, which was caused by particle size dependent current density distribution. These results show that particle size in electrodeposited composite materials can strongly affect the microstructure of the metal matrix. • Copper-diamond composite materials were produced by electrodeposition. • Copper-diamond thermal boundary conductance showed diamond particle size dependence. • Unexpected particle size effect on the microstructure of copper-diamond composites is demonstrated. [ABSTRACT FROM AUTHOR]