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The harsh environment of space, especially radiation of direct solar rays, can potentially raise the temperature of the spacecraft to harmful levels. Thermal control coatings (TCCs) fix the thermal condition of the spacecraft acceptable for its components. This is possible by diffusely reflecting all effective ultraviolet (UV), visible (VIS) and near infrared (IR) (NIR) wavelengths of solar radiation and emmition of IR energy. The most commonly used TCCs have used ZnO as a pigment, but absorption of the UV light by ZnO pigment can change the ideal condition of these TCCs. The aim of his study is the using the porous ZnO particles as pigment to prevent the UV absorption.

To enhance the efficiency of these coatings, in the present study, nano-porous zinc oxide particles were synthesized and used as pigments for white TCCs.

The results revealed that the proposed TCC (TPZ), Thermal control coating with porous ZnO had better reflection (scattering) and emittance properties in comparison with the coating using ZnO as a pigment (TZ coating); so this coating had a solar absorptance value equal to 0.141, whereas this value for TZ was 0.150. Furthermore, TPZ showed higher thermal emittance (0.937) in comparison with TZ (0.9). These changes were because of the improvement in the refractive index, shape and surface area of the pigments. The general trend of the scattering coefficients for the prepared coating, as calculated from the Kubelka–Munk equation, showed that scattering was more efficient in the UV region, as compared with the TCC containing ZnO pigments.

This type of pigment for the first time is evaluated in TCCs.

With the advent of micro‐satellites technology, passive thermal controls in the form of surface coatings have become important for onboard thermal management. The thermal coatings, however, suffer outgassing and mass loss due to their direct exposure to harsh thermal environment and high vacuum in space. The purpose of this paper is to discuss testing and evaluation on outgassing of AA6061‐T6 specimen surfaces treated with various types of anodized coatings of different thicknesses and the related mass loss before and after thermal exposure.

Samples of chromic acid, polytetrafluroethylene polymer, and black‐ and brown‐colour anodized aluminum coupons were subjected to high vacuum (∼1×10⁻⁶ mbar), before and after thermal baking at 120°C. Spectrum analysis of the outgassed material to know their quantities and proportion was conducted subsequently using a Quadrupole mass analyzer.

The surface coatings under study complied with the spacecraft requirements for the mass loss of less than 1 percent of the total mass of the coating material used for that surface. The mass spectrum analysis of the outgassed material indicated that the majority of the coating mass loss was on account of water vapours and organic solvents like ethylene.

These results provided a good insight into the reliability of the coating materials studied and the bonding between the aluminum substrates and the coatings.

The coatings and the technology needed for their application on aluminum are readily available. The present work on outgassing and mass loss in a simulated space environment will provide useful insight on their usage for micro‐satellites.

The point has been made that space exploration would probably not have been possible had it not been for surface coatings in one form or another. The most important of these coatings are the so‐called ablative thermal barriers and the thermal‐control surface coatings. The former are necessary to aid in the re‐entry of the vehicle, for at this point tremendous heat is generated by friction. The coating sacrifices itself and, in so doing, utilizes the heat and prevents it from gaining access to the interior of the vehicle. The thermal‐control coatings serve to maintain a constant temperature within the vehicle.

The purpose of this paper is to introduce the simple synthesis process of thermal-insulation coating by using three different nanoparticles, namely, nano-zinc oxide (ZnO), nano-tin dioxide (SnO₂) and nano-titanium dioxide (TiO₂), which can reduce the temperature of solar cells.

The thermal-insulation coating is designed using sol-gel process. The aminopropyltriethoxysilane/methyltrimethoxysilane binder system improves the cross-linking between the hydroxyl groups, -OH of nanoparticles. The isopropyl alcohol is used as a solvent medium. The fabrication method is a dip-coating method.

The prepared S1B1 coating (20 Wt.% of SnO₂) exhibits high transparency and great thermal insulation property where the surface temperature of solar cells has been reduced by 13°C under 1,000 W/m² irradiation after 1 h. Meanwhile, the Z1B2 coating (20 Wt.% of ZnO) reduced the temperature of solar cells by 7°C. On the other hand, the embedded nanoparticles have improved the fill factor of solar cells by 0.2 or 33.33%.

Findings provide a significant method for the development of thermal-insulation coating by a simple synthesis process and low-cost materials.

The thermal-insulation coating is proposed to prevent exterior heat energy to the inside solar panel glass. At the same time, it can prevent excessive heating on the solar cell’s surface, later improves the efficiency of solar cell.

This study presents a the novel method to develop and compare the thermal-insulation coating by using various nanoparticles, namely, nano-TiO₂, nano-SnO₂ and nano-ZnO at different weight percentage.

Finzel (American Paint and Coatings Journal, January 19 (1981) p. 19; Metal Finishing, June (1982) p. 49) has authored two review articles on silicones. He points out that silicones are mature products having first been introduced over thirty years ago. Their major use in the coatings field is for maintenance to provide protection against weathering, temperature extremes, and corrosive atmospheres. Silicones, when combined with other vehicles, impart increased resistance to moisture, chemicals, ultraviolet degradation, thermal shock, chalking, fading, and peeling. The major use, however, for silicones is for high temperature coatings as reactive intermediates and as paint additives.

The paper aims to discuss the inverse heat conduction methodology in solution of a certain parameter identification problem. The problem itself concerns determination of the thermophysical properties of a thin layer coating by applying the laser flash apparatus.

The modelled laser flash diffusivity data from the three-layer sample investigation are used as input for the following parameter estimation procedure. Assuming known middle layer, i.e. substrate properties, the thermal diffusivity (TD) of the side layers’ material is determined. The estimation technique utilises the finite element method for numerical solution of the direct, 2D axisymmetric heat conduction problem.

The paper presents methodology developed for a three-layer sample studies and results of the estimation technique testing and evaluation based on simulated data. The multi-parametrical identification procedure results in identification of the out of plane thin layer material diffusivity from the inverse problem solution.

The presentation itself is limited to numerical simulation data, but it should be underlined that the flake graphite thermophysical parameters have been utilised in numerical tests.

The developed methodology is planned to be applied in detailed experimental studies of flake graphite.

In the course of a present study, a methodology of the thin-coating layer TD determination was developed. In spite of the fact that it has been developed for the graphite coating investigation, it was planned to be universal in application to any thin–thick composite structure study.

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

Intumescent coatings are nowadays a dominant passive system used to protect structural materials in case of fire. Due to their reactive swelling behaviour, intumescent coatings are particularly complex materials to be modelled and predicted, which can be extremely useful especially for performance-based fire safety designs. In addition, many parameters influence their performance, and this challenges the definition and quantification of their material properties. Several approaches and models of various complexities are proposed in the literature, and they are reviewed and analysed in a critical literature review.

Analytical, finite-difference and finite-element methods for modelling intumescent coatings are compared, followed by the definition and quantification of the main physical, thermal, and optical properties of intumescent coatings: swelled thickness, thermal conductivity and resistance, density, specific heat capacity, and emissivity/absorptivity.

The study highlights the scarce consideration of key influencing factors on the material properties, and the tendency to simplify the problem into effective thermo-physical properties, such as effective thermal conductivity. As a conclusion, the literature review underlines the lack of homogenisation of modelling approaches and material properties, as well as the need for a universal modelling method that can generally simulate the performance of intumescent coatings, combine the large amount of published experimental data, and reliably produce fire-safe performance-based designs.

Due to their limited applicability, high complexity and little comparability, the presented literature review does not focus on analysing and comparing different multi-component models, constituted of many model-specific input parameters. On the contrary, the presented literature review compares various approaches, models and thermo-physical properties which primarily focusses on solving the heat transfer problem through swelling intumescent systems.

The presented literature review analyses and discusses the various modelling approaches to describe and predict the behaviour of swelling intumescent coatings as fire protection for structural materials. Due to the vast variety of available commercial products and potential testing conditions, these data are rarely compared and combined to achieve an overall understanding on the response of intumescent coatings as fire protection measure. The study highlights the lack of information and homogenisation of various modelling approaches, and it underlines the research needs about several aspects related to the intumescent coating behaviour modelling, also providing some useful suggestions for future studies.

UV curing processes of materials have to be specially designed accordingly in order to obtain the optimized property for different electronics applications. The purpose of this study is to characterize and study the curing and thermal behavior of a two‐component epoxy‐based UV curable coating in electronics assembly with various thermal analysis techniques. Curing behavioral change in terms of UV light, UV exposure time, wavelength, modulus, thermal stability, organic volatile outgassing and volume was discussed. Process optimization of coating materials that were UV cured at 30°, 100° and 150°C for 1 and 10 min was further investigated. Moreover, the relationship between photocuring conditions and the resultant surface hardness was studied and correlated from the results of dynamic microhardness measurements. Thermal and hardness properties of the above processed coating materials before and after isopropyl alcohol saturation were also investigated.