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The ability of a roof to absorb heat is crucial for maintaining temperature stability within a room. Therefore, natural material composite coatings utilization offers a viable option for modern roof development. This research investigates how using natural stone mixed with epoxy, and applied as a coating on a galvalume surface, influences thermal conductivity and reduces room temperature. Temperature measurements were collected around a small room with a composite-coated roof, utilizing different types of rock in the composition. Thermocouples were placed 20 cm above the roof's surface, attached to the roofing composite, positioned beneath the galvalume layer, and within the small room. The results demonstrate a reduction in thermal conductivity and room temperature when natural stone powder is added to the roof. Experiments using composite coatings with various stone types exhibit varying degrees of room temperature reduction. Consequently, this research concludes that the unique properties of natural stone can effectively lower the thermal conductivity of roofs and decrease room temperature.

The residual stress was predicted through a model of the multi-pass girth weld joint using Finite Element Method (FEM). Coupled Thermo-Metallurgy-Mechanical (TMM) analysis was carried out and the predicted final residual stress was compared with experiment data. To study the role of aged martensite in final residual stress, two models were simulated and discussed: models with and without aged martensite (prime martensite only). Comparing the experiment data, the model with aged martensite has shown closer prediction while the one without the aged martensite has over predicted the residual stress.

• The use of nanocomposite as anti-corrosion coating offers a superior performance by giving more durable protection against corrosion. • Cellulose nanocrystal (CNC) fillers are used in organic coatings to enhance performance in various shapes, sizes, types, and sources. • Nanoparticles made of as nanocellulose optimize coating formulations for specific applications. • Biobased nanomaterials in nanocomposites as anti-corrosion coatings offer a promising solution to the challenges faced by various industries. Organic coatings are interesting to study as one of the affordable and highly effective anti-corrosion coating techniques. Organic coating associated with nanocomposite fillers in the form of Cellulose nanocrystal (CNC) of different shapes, sizes, types, and sources that are used to enhance the coating performance. CNC's linear structure, composed of β-(1, 4)-D-glucose polymeric chain, contributes to the growth of microfibrils in crystalline cellulose. CNC's high thermal stability and mechanical strength provide an exceptional cross-linked network in polymer matrices as a coating. Organic coating techniques have been shown to improve corrosion resistance and other coating properties through various mechanisms. This article explores inorganic and organic-based polymer nanocomposite coatings as a solution to protect metal substrates from corrosion protection. The review also outlines how bio-based materials, as nano-fillers in various polymers, with various advantages. Combining with other nanomaterials in the polymer and functional group modifications capable of enhancing hydrophobic properties and outstanding bonding ability with the polymer matrix are expected to yield promising performance as barrier coatings against corrosive species. This study concludes that bio-based nanomaterials with intrinsic properties such as low density, high aspect ratio, outstanding mechanical properties, biocompatibility, and biodegradability are important reasons for these materials to be used for anti-rust nanocomposite applications and have great potential to be developed as nanofillers in nanocomposite polymer matrices in high-performance metal coatings and various applications in the future. [ABSTRACT FROM AUTHOR]

Natural fibers are available as an essential substitute for synthetic fiber in many applications. However, the sensitivity of Chinese Windmill Palm or Trachycarpus Fortune Fiber (TFF) to water causes low interfacial bonding between the matrix and the fiber and at the end reduces the mechanical properties of the composite product. Alkaline treatment improves mechanical properties and does not affect water absorption. Hence, additional treatment in the coating is required. This study uses alkaline treatment and coating modification using blended chitosan and Acrylated Epoxidized Soybean Oil (AESO). Blend coating between AESO and chitosan is performed to increase water absorption and mechanical properties. TFF water resistance improved significantly after the coating, with water absorption of the alkaline/blend coating-TFF of 3.98 % ± 0.52 and swell ability of 3.156 % ± 0.17. This indicated that blend coating had formed a cross-link of fiber and matrix after alkalization. Thus, the single fiber tensile strength increased due to the alkaline treatment, and water absorption decreased due to the coating. The combination of alkaline treatment and blend coating on TFF brings excellent properties, as shown by the increase in tensile strength in both single fiber test and composite. [ABSTRACT FROM AUTHOR]

Circulating Fluidized Bed (CFB) boiler often experience leaks in the wall tube due to corrosion and abrasion of the bed material after use that varies between 3 and 8 months. To avoid erosion corrosion, a coating was done in the form of Chrome Clad Tube Armor (CTA). In this research, a Failure Analysis (FA) was performed on the characterization of the boiler tube using several types of samples, which are Wall Tube Without Coating (WT) and CTA (in new condition and after eight months of use). Macro visual, Field emission scanning electron microscopes (FE-SEM), Fourier-transform infrared spectroscopy (FTIR), corrosion, and Thermogravimetric analysis (TGA) tests showed that the CTA type has better corrosion and thermal resistance. The hardness values of the CTA and WT coating substrates after eight months of use were 197.75 and 195.2 HV. The failure mechanism on the tube was caused by high temperatures (long-term overheating) and friction between the tube and the fluid or metal. Wall tubes in furnaces fail due to erosion and corrosion due to fluid and solid particle mixtures and environmental contact., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)