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As the interface material for tungsten fiber reinforced tungsten composites (Wf/W), yttrium oxide thin films were prepared via an electrophoretic deposition (EPD) method in this study. The yttrium oxide dispersion is optimized based on its Zeta potential. The coating process was performed on the tungsten weaves (anode), and stainless steel was used as the counter electrode (cathode). The coating structure obtained from the EPD process was homogeneously distributed on all the fibers of the weave, but possess a porous structure. In addition, to optimize the coating process, the voltage influence on the coating process is demonstrated. Using the EPD prepared yttria interface, Wf/W is produced based on a chemical vapor deposition process. Initial mechanical test shows a promising property with extrinsic toughening mechanisms and high damage resilience.

The present study deals with the warm temperature deformation behavior of the Ti–6Al–4V alloy throughout investigating the flow behavior and the correlated microstructure evolutions. Toward this end, the tension and compression tests were conducted at temperatures of 100, 300, 500, and 600 °C under the strain rate of 0.001s−1. The low compressive formability of the material and premature fracture at 100 and 300 °C was attributed to the insufficient number of operative slip systems at this relatively low temperature regime. In contrast, in tensile mode the work hardening capacity was increased and the portion uniform elongation was considerable. In fact, the higher activity of pyramidal slip systems and higher dislocation maneuverability in tensile mode provided a proper condition for substructure development, which resulted in higher strain accommodation. Interestingly, the tensile deformed microstructures at 100 and 300 °C were strongly texturized and most of α-grains were oriented around the midline of [0001]-[-1100] or even toward the [-1100]. This was attributed to the lower critical resolved shear stress of pyramidal slip in tension mode, which caused the rotation of the axis toward extension direction. The significant flow softening in compressive mode and appreciable post-necking deformation (due to diffused necking) in tensile mode were the main characteristics of the flow curves at 500, and 600 °C. This was attributed to the extended dynamic recovery and continuous recrystallization, spheroidization, and geometric softening. It was believed that the intensified substructure development facilitated the fragmentation and boundary splitting mechanism, therefore, trigger the spheroidization of α phase.

The plasma electrolytic oxidation is an innovative method for the surface treatment of titanium and its alloys. This review provides an overview of the historical development of the process and summarizes the current state of the art. The chemical as well as the electro- and plasma-chemical basics of the layer forming mechanisms, which comprises the substrate/electrolyte interface before discharge initiation and the different types and stages of plasma electrolytic discharge phenomena are explained within the context of titanium-based materials. How these phenomena can be influenced by the use of suitable electrolytes and controlled by the electrical regime is described. Subsequently, the microstructures and composition of the layers are described in detail, and the properties for specific applications are then discussed. The resistance of a PEO coating to corrosive environments, tribological factors, and alternating mechanical stress is viewed critically, and the extensive functional properties such as physiological compatibility, photocatalytic activity, and decorative properties are revealed. Finally, examples of various practical applications in the medical engineering, aviation, automotive, and environmental technology fields, as well as other branches of industry, are presented.