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The design of layers and fabrication methods strongly affect the stress bearing capacity and crack propagation in functionally graded porous titanium (FGPT). Thus, in this study, uniform and functionally graded porous titanium (in three and five-layer structures) samples were fabricated using spark plasma sintering at 440 °C and 50%vol. space holder (NaCl). Compression results proved that selecting the highest NaCl in the center of five-layered samples, besides the smoothest porosity gradient, increases energy absorption up to ≅360 % compared with the uniform foam. The architectural design, along with the energy absorption, affects the crack direction and fracture pattern remarkably. Obviously, two types of cracks path, i.e., vertical and oblique, were detected in uniform and different graded samples, which the latter direction highlighted the Griffith rupture mechanism. Meanwhile, although trumpet-like and crushed/disc fracture patterns perceived in layered structures, promptly fragmented patterns were dominated in the uniform porous sample. This work provides an appropriate method with a suitable layers arrangement to fabricate FGPTs with incredible energy absorption due to crack arresting/deflecting and homogenizing strut thickness.

The formation of tortuous filmwise condensation in desalination setup alongside with reduction in thermal conductivity is a challenge accompanied by efficiency loss. This issue is directly influenced by hydrophobicity, which is a function of surface roughness, as well as surface chemistry. In this sense, the hydrophobicity of variant silicone epoxy based nanocomposites was evaluated to identify the optimum proportion composite for surface condensation of desalination setup. To this end, three types of fumed silica with distinct surface chemistry were utilized in a matrix at the weight percentage of 0.5, 1, 1.5, and 2. To investigate the hydrophobicity, roughness, and distribution of reinforcement, a series of characterization techniques, including contact angle, AFM, and FESEM were used. It was found that, in comparison to pure matrix, the nanocomposite modified with 5 wt % of hydrophobic additive and 0.5 wt % of hydrophilic fumed silica nanoparticles (SE/5B/0.5R200) has the highest contact angle (about 35%) and roughness (13 times), due to the migration of nanoparticle onto the surface. Also, coating the condensation surface of the desalination setup with optimum thickness, i.e. 60 × 10−6m, resulted in the efficiency improvement by about 33 % compared to the uncoated setup, even after 168 hrs. Indeed, dropwise condensation, straight path movement of droplets, besides thermal conductivity adjust the efficiency.