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Electrospark deposition (ESD) attracts special attention from scientists and engineers because of its unique advantages. However, the ESD process has been carried out by hand up to the present. This prevents ESD from preparing complex curve/surface coatings owing to manual operation characteristics. To meet the coating precise preparation requirements for a lot of parts with complex surface from various industrial fields, this paper aims to obtain a new automatic ESD equipment, process and preparation methodology for complex surface coatings.

By designing a special deposition holder and re-programming programmable machine controller, an ESD power supply and a computer numerical control milling machine are integrated to obtain an electrospark-computer integrated deposition system (ES-CIDS). Then, based on the ES-CIDS, a new ESD process, named electrospark-computer numerical control deposition (ES-CNCD) is developed. Furthermore, complex surface coatings are depicted using non-uniform rational B-spline mathematical model and modeled in a special software developed via MATLAB. Finally, deposition programs for a complex coating are generated using golden section interpolation method, and transferred to and executed by the ES-CIDS to accomplish the preparation of the complex surface coating.

This paper demonstrates that it is possible and feasible to prepare complex surface coatings via an automatic ESD process (namely, ES-CNCD) precisely.

This paper can make automatic ESD process get more attention from scientific researchers and engineers, and promote the research of the ES-CNCD process/equipment.

The ES-CNCD process can be used in the manufacturing of complex surface coatings, and in the remanufacturing of complex shape parts.

The ES-CIDS/ES-CNCD can promote the development of related equipment and technology, and bring opportunities and employment to ESD industry.

This work prepares complex surface coatings precisely for the first time using a new automatic ESD process (ES-CNCD), which has wide application prospects in various industries.

This paper aims to present a new trajectory optimization approach targeting spray painting applications that satisfies the paint thickness requirements of complex-free surfaces.

In this paper, a new trajectory generation approach is developed to optimize the transitional segments at the junction of adjacent patches for straight line, convex arc and concave arc combinations based on different angles between normal vectors of patches. In addition, the paint parameters including the paint gun velocity, spray height and the distance between adjacent trajectories have been determined in the generation approach. Then a thickness distribution model is established to simulate the effectiveness of trajectory planning.

The developed approach was applied to a complex-free surface of various curvatures, and the analysis results of the trajectory optimization show that adopting different transitional segment according to the angle between normal vectors can obtain the optimal trajectory. Based on the simulation and experimental validation results, the proposed approach is effective at improving paint thickness uniformity, and the obtained results are consistent with the simulation results, meaning that the simulation model can be used to predict the actual paint performance.

This paper discusses a new trajectory generation approach to decrease the thickness error values to satisfy spray paint requirements. According to the successfully performed simulation and experimental results, the approach is useful and practical in overcoming the challenge of improving the paint thickness quality on complex-free surface.

The purpose of this paper is to study the effect of chromium content on the microstructure and corrosion resistance of Ni-Cr coating.

Ni-Cr coating was prepared by pulse current electrodeposition with trivalent chromium. On the basis of studying effect of electroplating parameters on composition and morphology, Ni-Cr alloy coatings with various chromium contents were obtained. The microstructure was characterized by scanning electron microscopy, X-ray diffractometer and transmission electron microscopy. Corrosion behavior was studied by potentiodynamic polarization and electrochemical impedance spectroscopy techniques.

Electrodeposited chromium was solidly dissolved in nickel and refined the grain of the coating. With the increase of Cr content, the corrosion resistance of Ni-Cr coating was enhanced, which is due to the formation of continuous nickel hydroxide and compact chromium oxide passive films.

Ni-Cr alloy coating without penetration crack was prepared in trivalent chromium electrolyte, and the mechanism of its excellent corrosion resistance was proposed.

This paper aims to investigate the prepared modified alkyd and poly(ester-amide) (PEA) resins as antimicrobial and insecticide binders for surface coating applications.

Salicylic diethanolamine and 4-(N, N-dimethylamino) benzylidene glutamic acid were prepared and used as new sources of polyol and dibasic acid for PEA and alkyd resins, then confirmed by: acid value, FT-IR and 1H-NMR. The coating performance of the resins was determined using measurements of physico-mechanical properties. The biological and insecticide activities of the prepared resins were investigated.

The tests carried out revealed that the modified PEA and alkyd enhanced both phyisco-mechanical and chemical properties in addition to the biological and insecticide activities. The results of this paper illustrate that the introduction of salicylic diethanolamine and 4-(N, N-dimethylamino) benzylidene glutamic acid within the resin structure improved the film performance and enhanced the antimicrobial activity performance of PEA and alkyd resins.

The modified alkyd and PEA organic resins can be used as biocidal binders when incorporated into paint formulations for multiple surface applications, especially those that are exposed to several organisms.

Modified alkyd and PEA resins based on newly synthesized modifiers have a significant potential to be promising in the production and development of antimicrobial and insecticide paints, allowing them to function to restrict the spread of insects and microbial infection.

The purpose of this study is to develop a new protective coating formulation for industrial use, using benzodiazepine derivatives as double function additives.

Benzodiazepine’s derivatives of types (3–5) were prepared and confirmed by infrared, Mass, ¹H-Proton nuclear magnetic resonance (NMR) and ¹³C NMR spectra. The synthesized compound was physically incorporated in the alkyd paint formulation by pebble mill grinding until all particulates are smaller than 20 ums. The prepared coatings were applied by air spray on steel panels. The physical, mechanical characteristics, corrosion resistance and antimicrobial test of the prepared coatings were studied to evaluate the prepared compounds drawbacks.

The results of the mechanical and physical properties of the paint formulation revealed that the paint formulation incorporating benzodiazepines derivatives 3–5 performed best and improved corrosion-resistance and antibacterial activity tests.

In alkyd paint, heterocyclic compounds are the most used antibacterial additives. Other functionalities of these compounds, such as corrosion inhibitors, might be studied to see if they are suited for these applications.

Because of the activity of various benzodiazepine derivatives, which may be attributable to the presence of some function groups such as sulfonamide aromatic amino NH₂ group, and elements such as Sulphur, Nitrogen, Chlorine, in its chemical structure. As a result, paint compositions including these compounds as additives can be used as dual-purpose paint and for a variety of industrial applications.

The research demonstrates how a low-cost paint composition based on synthesized benzodiazepine derivatives 3–5 may be used as a dual-function paint for industrial use.

Existing production plant is redesigning in accordance with requirements of product marketing. The philosophy of product automation is changing and at the same time so is the whole complex of technical method used for production. Industrial robots are considered to be the most important element for automation. The paper presents a number of new robot designs with point‐to‐point and continuous path control. Consideration is being given to the problem of effective application of “intelligent” robots. The need to improve the accuracy of industrial robots performance is substantiated.

Paper aims to preparation of new acid disperse dyes based on thiadiazol derivatives and evaluation of their use as antimicrobial colorants in digital transfer-printing ink formulations for printing onto polyester fabric substrates.

New disperse dyes based on 1,3,4 - thiadiazol derivative (dyes 1–3) were prepared and evaluated by different analysis then formulated as colored materials in the ink formulations. The viscosity, dynamic surface tension and particle size distribution of the prepared inks were measured. The printed polyester fabric substrates were tested using a variety of tests, including light fastness, washing, alkali perspiration and Crock fastness, as well as depth of penetration. Density-functional theory (DFT) calculations were carried out at the Becke3-Lee-Yang-parr (B3LYP) level using the 6–311** basis set, and the biological activity of the prepared disperse dyes was investigated.

The obtained results of the physical of the prepared ink revealed that thiadiazol disperse ink is a promising ink formulation for polyester printing and agrees with the quality of the printed polyester fabric. The optimization geometry for molecular structures agreed with the analysis of these compounds. The HOMO/LUMO and energy gap of the studied system were discussed. The molecular docking analysis showed strong interaction with DNA Gyrase and demonstrated to us the high ability of these inks to act as antimicrobial agents.

The prepared inks containing the prepared thiadiazol disperse dye were high-performance and suitable for this type of printing technique, according to the results. The prepared inks resist the growth of microorganisms and thus increase the ink's storage stability.

The prepared disperse dyes based on 1,3,4 - thiadiazol derivative (dyes 1–3) can be a promising colorant in different applications, like some types of paint formulations and as a colorant in printing of different fabric substrates.

The ability to produce a uniform composition, high corrosion resistance with a hard coating layer during the electroless coating techniques are mainly based on the plating bath composition. The complexing agent is one of the most important components that control the coating layer properties. This paper aims to investigate the effect of the glycine as a complex agent on the surface and corrosion properties of Ni-P and Ni-P/Al₂O₃ electroless coating.

In this study, the effect of glycine as a complexing agent on the final surface and corrosion properties of the Ni-P and Ni-P/Al₂O₃ coatings has been investigated. The surface morphology and composition of the coated samples were investigated by scanning electron microscope (SEM) imaging and energy dispersive x-ray spectroscopy (EDS) analysis. Linear polarization scan and electrochemical impedance spectroscopy techniques were used to investigate the corrosion properties of the coating layer.

The results clarify that, glycine has a remarkable effect on the porosity content of Ni-P and Ni-P/Al₂O₃. It was found that increasing of glycine concentration results in higher porosity content in the coating layers. Also, the porosity in the coating layers minimizes the protectability of the coating against corrosion. The results also show that adding nano-alumina (Al₂O₃) to the coating path has improved the corrosion properties by decreasing the porosity in the coating layer. The scanning electron microscope (SEM) images showed that the concentration of glycine affects the content and distribution of alumina nanoparticles embedded in the coating layer. Also, it was observed that using a high concentration of glycine (0.4 M glycine), the alumina tends to agglomerate and the final alumina content in the coating was decreased.

The present study reveals that the quality of the final coating plays a major role in the corrosion performance of the steel substrate. The coating quality can by improve remarkably by optimization of the complexing agent used in the plating bath, to minimize the porosity involve in the coating layer.