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ZrO₂ is a kind of inorganic material with high hardness, high tenacity, antiwear, corrosion, and resistance, therefore it is regarded as an ideal nanolubricant material. But untreated ZrO₂ nanoparticles are reunited in the lubricant medium instead of monodisperse because the consistency is poor between the material surface and lubricant, which restricts its application as a nanolubricant additive. Through theoretical analysis, this paper designed that the surface of ZrO₂ nanoparticles was modified with silicon coupling agent, and it was changed to lipophilic surface, so it was possible to be a monodisperse system in the lubricant. The modified spherical nanoparticles of ZrO₂ were dispersed in the lubricant and they could play a molecular bearing part in lubricating media. When the friction surface reached a certain load and temperature, once the metal surface produces the deficiency, physical adsorption and chemisorption on the metal surface would be produced because of high nano-ZrO₂ particle activity, and even the N atom in the particle surface silane tends to be absorbed to the metal surface to form chelate compound, and make ZrO₂ particles enrich to defective locations of the metal surface. Then, a self-repairing lubricated membrane in the friction surfaces was set up, and it can play the function in the antifriction, antiwear, and surface dynamic self-repair.

The surface modification mechanism of polyvinyl chloride (PVC) by ozonation was investigated to study the selective hydrophilization of PVC surface among other plastics. Infrared analysis confirmed the increase of hydrophilic groups. XPS analysis revealed that the increase was due to the structural change in chlorine group in PVC to hydroxylic acid, ketone, and carboxylic groups by ozonation. This chemical reaction by ozone could occur only for polymers with chlorides in its structure and resulted in the selective hydrophilization of PVC among various polymers.

Phytic acid (PA) and 3-aminopropyltrimethoxysilane (APTMS) were selected as organic additives and respectively doped into Na₂SiO₃-NaOH electrolyte to prepare ceramic coatings on AZ31B Mg alloys by Plasma Electrolytic Oxidation (PEO) method. The influences of two additives on corrosion resistance of the PEO coatings were compared. The microstructure, composition and corrosion resistance of the PEO coatings were examined by SEM, EDX, XPS, XRD, potentiodynamic polarization test and EIS measurement. The results indicated that each additive increased both the coating thickness and corrosion resistance. However, the PA-doped PEO coating achieves larger thickness but exhibits worse corrosion resistance than the APTMS-doped PEO coating due to larger pore size and looser microstructure.

Disparate industry bodies across the planet use pallets for storing large and heavy objects. Pallets provide an assurance of safe handling of material (cargo) and storage of material in a damage-free environment. In this work, an attempt has been made to analyze and investigate making pallets out of ULTEM 9805 using the latest additive techniques (FDM). The maximum deflections and von Mises stresses are analyzed for the disparate boundary conditions indicating the possible alternatives or loads to be used. Study of surface (morphology) and characteristics was done in order to establish the relationship between pallet surface and its application. The factors of load, maximum and minimum values, ascertained in each stage are 168.15, 522.22, 215.31 and 316.79 kPa as well as 18.77, 6.7, 1.2 and 35.84 kPa for the floor, rack, forklift and conveyor load supports, respectively. A cross-hatched design causes a rise in capacity of the shear factor owing to the length of the span being in correlation with rectilinear fill. The filament of surface, made of ULTEM 9805, exhibits a level of roughness of 43.14 μm on the pallet surface indicating better holding capacity and grip. A 9^∘ peak shift is comprehended with respect to XRD, indicating a compressive residual factor measured at 76.47 MPa.

In this study, lemon juice at different concentrations as a new additive was poured into the bath of the anodizing process to enhance the mechanical properties of the manufactured aluminum oxide layers. X-ray diffraction (XRD) and field-emission scanning electron microscopy were utilized to detect formed phases and microstructure, respectively. To investigate mechanical properties, microhardness, indentation toughness, and wear tests of various aluminum oxide layers were performed. The XRD patterns showed a crystalline phase of $\gamma$-Al₂O₃ for all oxide layers. The microhardness of modified layers increased up to 62.2% compared to the unmodified layer. However, by increasing the additive concentration to 2.5 vol%, the hardness decreased. This was based on increasing the pore size of layers. The lowest friction coefficient with a value of 0.53, the lowest wear rate, and the highest indentation toughness was also related to the modified aluminum oxide layer when the concentration of the additive in the bath was 0.3 vol%. For this modified layer, the value of COF/$H$ was the lowest, and the pore size of 50 nm was the lowest among the layers.