Interactive thermochromic coatings based on Leuco dye are most commonly used in research for building cooling applications. The coatings developed by the authors are primarily aimed at industrial applications on metal substrates, mainly for safety reasons. Thanks to a higher transition temperature associated with a significant change in shade, they have the potential to prevent burns and can be used as an element of active protection in exposed areas. Interactive thermochromic materials with different base matrices and two dispersion methods have been monitored and tested over the long term to gain an overall impression of their behaviour and applicability. The monitoring of colour characteristics helps to understand the behaviour of the thermochromic pigment in different primer matrices. The values of L*, a*, and b* and the spectral curves measured by a spectrophotometer were compared. Colour differences between the cold and heated conditions were also evaluated. ΔE* values for acrylate polyol reached up to 39. For waterborne paint, they varied according to the method of dispersion—when using a saw tooth stirrer, ΔE* was 23, and when mixing with a rotor-stator device, up to 56. Similarly, for the polyurethane matrix: ΔE* went up to 39 for stirring with a saw tooth stirrer while ΔE* was 64 for the rotor-stator. From the measurement of the behaviour of the coatings during temperature exposure, it can be concluded that most of the samples show a decrease in the transition temperature. Monitoring the behaviour of coatings during cooling is important for choosing a suitable base matrix that will ensure the long-term functionality of the coating and declare the temperature range of its use for safety applications.

The subject of the research is the possibility of using laser surface hardening to modify the tribological properties of ADI castings. ADI cast irons are a very progressive material; these cast irons find their application (due to their characteristic properties) in demanding applications. In these applications, the tribology of their surface is an essential parameter. This research focused on the change in tribological properties due to laser hardening of the surface layers. ADI cast iron samples processed at different isothermal holding temperatures were selected for the experiment. This is because these temperatures have a major influence on the initial structure (before laser exposure), which also affects the laser hardening process. To analyze the structural changes, metallographic examinations were performed. The microhardness was also measured on each sample in relation to the distance from the surface. The samples were also subjected to a tribological test (linear reciprocating tribometer) during which the coefficient of friction was recorded. The surface conditions after the tribological experiment were evaluated using an electron microscope. Tribological experiments revealed very different behavior of laser-hardened ADI cast iron surfaces depending on their isothermal holding temperature. At the same time, a homogeneous martensitic layer on the surface (a consequence of the relatively uniform distribution of carbon in the initial ausferritic structure) was achieved by laser, which contributed to a significant increase in hardness and wear resistance. A trend of decreasing friction coefficient as a function of isothermal holding temperature was observed for non-laser-hardened surfaces. This phenomenon supports the theory of a possible martensitic transformation of the high-carbon austenite contained in the structure of ADI castings.

This paper focuses on the evaluation of the surface pretreatment of glass specimens and its effect on the strength of bonded joints. The experimental portion of this study includes the testing of three types of surface treatments (degreasing, blasting and etching) and the use of three types of adhesives (two-component epoxy, instant cyanoacrylate and two-component acrylate). Surface roughness measurements and bond strength testing using the pull-off test and shear tests were performed on the samples. The results showed that surface etching in conjunction with the Auratech AR 708 acrylic adhesive provided the highest bond strength. These findings contribute to the development of more reliable and stronger bonded joints for industrial applications. Scientific knowledge lies in determining the effect of appropriate glass surface treatment on adhesive adhesion under load with respect to joint aging due to environmental effects (UV, temperature, humidity) for transparent adhesives. This study provides an assessment of the effect of surface cleanliness on adhesion to glass.

The tantalum carbide coatings were deposited on substrates made of 12Kh18N10T steel, ZhC6 alloy, and molybdenum by reduction of TaBr₅ and CCl₄ vapors with cadmium vapors at temperatures of 950–1000 K. The average deposition rate of coatings on molybdenum was ~5 μm/h, on ZhC6 alloy was ~6 μm/h, and on 12Kh18N10T steel was ~8 μm/h. The coatings were formed as columnar grains on the substrate surface and as a diffuse layer in the substrate material. The surface layers contained mainly tantalum monocarbide TaC_y (y = 0.72–0.86) and a small fraction of tantalum. The coatings on the surface of ZhC6 alloy and 12Kh18N10T steel flaked off with increasing thickness, which was due to different thermal expansion of the coating and substrate, as well as concentration inhomogeneity and phase transitions in the substrate material during coating deposition and during the heating and cooling processes.

The changes in the material properties of water turbine blades are characterized an undesirable process, which could lead to the end of usable life or to the emergency conditions of this turbine. For this reason, it is important to determine o...

Surface treatment technologies are pivotal across diverse industrial sectors such as mechanical engineering, electrical engineering, and the automotive industry. Continuous advancements in manufacturing processes are geared towards bolstering efficiency and attaining superior product quality. This study aimed to empirically compare practical outcomes with theoretical insights. Employing galvanic zinc plating under constant voltage with varying plating durations unveiled a correlation between coating thickness and electrolyte composition alongside plating duration. The graphical representation delineated the optimal electrolyte composition conducive to maximal coating thickness. Notably, an evident decrease in leveling ability was noted with prolonged plating durations. The experiment corroborated the notion that theoretical formulas for coating thickness estimation possess limited accuracy, often resulting in measured values surpassing theoretical predictions. These findings underscore the imperative for refined theoretical models to comprehensively grasp galvanic surface treatment processes.