Laminated glass is ever more frequently used nowadays. This applies to the automobile industry and the construction industry. In cars, this refers mostly to the front and rear windows, whereas in construction, technical safety glass is used for railings and window glass. The task of this type of glass is to provide sufficient resistance against mechanical impact and unpleasant weather conditions. At the same time, if it is damaged, it has to break into the smallest possible pieces, or, wherever possible, the glass should remain intact on the interlayer film to prevent shards from injuring people and animals in the immediate vicinity. The paper deals with the recycling of laminated glass, especially with the effective separation of glass (in the form of cullet) from the polyvinyl butyral (PVB) interlayer film. The experimental research is focused on the mechanical separation of glass from the interlayer film by vibration, and also on the chemical cleaning of PVB film in order to allow subsequent recycling of both materials. The results quantify the efficiency of mechanical separation in the form of weight loss of the sample of laminated glass and define the particle size distribution of glass cullet, which is an important parameter in the possibility of glass recycling. The research leads to a methodology proposal for the separation of glass and PVB film and the design of equipment for this method.

High-chromium cast irons are used as abrasion resistant materials. Their wear resistance depends on quantity of carbides and the matrix supporting these carbides. The paper presents the results of cast irons of chemical composition (in wt. %) 19–22 Cr and 2–4.5 C alloyed by 1.7 Mo + 5 Ni + 2 Mn to improve their toughness, which were tested in working conditions of ferroalloys crushing. Tests showed that these as-cast chromium cast irons with mostly austenitic matrix achieved the hardness of 38-45 HRC, but their relative abrasion resistance Ψ ranged from 1.3 to 4.6, was higher comparing to the tool made from the X210Cr12 steel heat treated on hardness 61 HRC. The transformation of austenite into martensite occurs not only at the worn strained areas (on a surface of scratch) but also in their neighbourhood. Due to the work hardening of relatively large volumes of transformed austenite the cast iron possesses high abrasion resistance also on the surfaces where low pressures are acting. The tough abrasion-resistant cast iron well proved for production of dynamic and wear stressed castings e.g., crusher hammers, cutting tools for ceramic etc.

The foundry industry is an industry with a large production of waste. One such type of waste is fine-grained to dust-like waste, depending on the stage of the foundry process in which it is generated. As part of this research, dust samples were collected from three Slovak foundries producing castings from gray iron, ductile iron, and steel. The aim of the experiments was to recycle iron from dust materials in the foundry process. Based on the chemical composition of the dust, samples with the highest iron content were selected and added to the charge of the electric induction furnace (EIF). Since it was not possible to add dust material directly into the EIF, the dust was modified by pelletizing and briquetting using three types of binders selected according to the foundries’ requirements. Pellets were prepared using dust from only one type of foundry waste and were used as part of the charge in the EIF. In the case of briquetting, different binder contents in the briquette mixture were tested to evaluate their effect on the strength and disintegration of the briquettes. Based on the foundries’ requirements that the binder had to be low-cost and that we had to not contaminate the melt (thus requiring a minimal amount), not affect the furnace operation, and not degrade the properties of the produced cast iron, briquettes with the best properties were selected and used as part of the charge for cast iron production. Samples of the cast iron produced this way were taken for chemical analysis, and specimens were prepared for tensile strength testing. The results showed that the use of briquettes, in limited amounts, did not have a negative impact on the chemical composition of the cast iron, the melting process, or its tensile strength.

In this study, the microstructure of surface layers with varying roughness (Ra parameters) was analysed using scanning electron microscopy (SEM) to optimize tribological properties in engineering design. SEM revealed key microstructural features-sharp and mild protrusions, pitting, microcracks and contaminants-that were not available in traditional profilometry. Reducing the Ra value improved surface uniformity by reducing irregularities and defect lengths, which had a positive effect on tribological properties and surface durability. However, defects were still present even at Ra < 1.25 μm, indicating the "Law of Microstructural Roughness," which emphasizes the inevitability of surface irregularities despite minimizing roughness. The integration of SEM results with profilometric methods enabled comprehensive identification and assessment of defects, combining microstructure with tribological properties. Results suggest that controlled roughness is key in combining materials and optimizing functional surfaces, particularly in the aerospace, biomedical and automotive industries, where reliability under demanding operating conditions is a priority.