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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. [ABSTRACT FROM AUTHOR]

This paper presents the results of studies on the growth kinetics, microstructure (SEM/EDS) and corrosion behavior of coatings obtained by hot-dip galvanizing process in baths containing Bi additive. The coatings for testing were produced on low-silicon steel in a Zn bath containing 0.04, 0.12 and 0.4 wt.% Bi. The corrosion resistance of the coatings was determined comparatively in standard Neutral Salt Spray Tests (NSST) (ISO 9227) and sulfur dioxide test (SDT) in a humid atmosphere (ISO 22479). Potentiodynamic tests and electrochemical impedance spectroscopy measurements were conducted. It was found that the addition of 0.04 and 0.12 wt.% Bi reduces the total thickness of the coatings and the thickness of intermetallic layers, while the content of 0.4 wt.% Bi in the bath increases the thickness of the layers forming the coating. Direct corrosion tests (NSST and SDT) and electrochemical tests showed that the addition of Bi to the zinc bath reduces the corrosion resistance of the coatings. The corrosion resistance of the coatings decreases with increasing Bi concentration in the zinc bath. In the microstructure of the coatings, it was found that Bi precipitates mainly on the surface of the coating, but also on the cross-section of the outer layer and ζ intermetallic layer. Bi precipitates, due to their cathodic nature, affect the reduction of the corrosion resistance of the coatings with the increase of their content in the bath. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]