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The requirements placed on the foundry industry are mainly related to the need to maintain an appropriate quality–price ratio of the product and to maintain an appropriate production regime that takes into account modern legal solutions related to environmental protection. This work is part of the trend of searching for new or previously unused materials from renewable sources in moulding sand technology. This article concerns the possibility of using barley malt in moulding material technology as a binding material. The presented work contains the results of research on the release of gases during casting, where high temperatures cause the decomposition of chemical substances. The tests confirmed that moulding sands with barley malt as a binder do not cause excessive emissions of harmful gaseous products when pouring moulds with liquid casting alloy. The volume of gases formed was smaller than that of commonly used moulding sands with other binders. The total volume of gases produced and the kinetics of their release indicate that casting in this type of moulding sand did not cause any technological inconvenience or casting defects of gaseous origin. This was confirmed by research involving obtaining iron castings in industrial conditions using barley malt as a binder in moulding sand technology, which were then subjected to visual assessment and roughness analysis.

This work concerns two stages of research into plasma nitriding (change of nitriding steel and modification of nitriding parameters). In the first stage, pins obtained from currently used steel were compared with pins made of an alternative material available on the market, using the same nitriding process parameters. As a result of the metallographic tests carried out, in the first case, the presence of a thin, porous, and heterogeneous nitrided layer or its absence was found, with the core in its raw state and not thermally improved. In the second case, the presence of a nitrided layer of small thickness with noticeable porosity on the surface of the sample was found, but with a core after heat treatment (incorrect process parameters). Therefore, modification of the parameters of the nitriding process was proposed, in terms of a mixture of gases, currents, time, and temperature of the nitriding process. As a result, a satisfactory effective thickness of the nitrided layer was obtained, consisting of a white near-surface zone with ε and ε + γ′-type nitrides with a thickness of 8.7 to 10.2 µm, and a dark zone of internal nitriding with γ′ nitrides. The nitrides layer was continuous, compact, and well adhered to the steel surface. In the core of the samples, the presence of a fine-needle tempering sorbite structure with a small amount of fine bainite, which is correct for the steel after heat treatment and nitriding, was found. The most favorable parameters of the ion nitriding process were gas flow rate (1.5 L/min N; 0.4 L/min H; 0.3 L/min Ar); currents (BIAS—410 V 4.0 A, SCREEN—320 V 4.0 A); time (26 h and 35 min); and temperature (550 °C).

Standardization is a key element in the effective use of lean manufacturing methodologies and tools for achieving process sustainability. Their combination is conducive to eliminating waste and improving the efficiency of production processes and guarantees the company that employees use the most efficient tools and do not waste time on unnecessary activities. These activities can be further improved by using digital solutions, in accordance with the concept of Industry 4.0. Therefore, the authors have developed the e-Lean system, whose task is to digitize selected lean manufacturing tools. The subject of this work is analysis of the functionality and effectiveness of the essential part of the e-Lean system in the form of specialized TPM (Total Productive Maintenance) software as an application. During implementation in a construction production company, the TPM application was tested by lean manufacturing and maintenance specialists. The research consisted of assessing the functionality and efficiency of processes in relation to conventional TPM solutions. Additional functionalities of the e-Lean system have been confirmed, such as systemic approval of machinery inspection, which requires passing all necessary steps at individual inspection points, direct access for supervisors to the results of inspection activities and their status, direct and easy access to photographic documentation of machines added during inspection both in optimization of working time and its course (e.g., the optimal number of steps taken by the employee during the inspection), as well as an efficient system of motivating employees (collecting points). The improvement in the effectiveness of processes was determined by measuring the control times for three control points (polymerization furnace, packing area, and defibering machines). The average control time was reduced from 16,200 to 13,923 s. Thus, thanks to the use of the application, it was found that the efficiency of using the TPM tool was increased by approx. 15% compared to previously used non-digital solutions.

In the paper, the effects, on basic usable properties (abrasive wear and corrosion resistance), of solidification (acc. to the stable and non-stable equilibrium system) and transformations occurring in the matrix during the cooling of castings of Ni-Mn-Cu cast iron were determined. Abrasive wear resistance was mainly determined by the types and arrangements of high-carbon phases (indicated by eutectic saturation degree), and the kinds of matrices (indicated by the nickel equivalent value, calculated from chemical composition). The highest abrasive wear resistance was found for white cast iron, with the highest degree of austenite to martensite transformation occurring in its matrix. Irrespective of solidification, a decrease of the equivalent value below a limit value resulted in increased austenite transformation, and thus, to a significant rise in hardness and abrasive wear resistance for the castings. At the same time, corrosion resistance of the alloy was slightly reduced. The examinations showed that corrosion resistance of Ni-Mn-Cu cast iron is, too a much lesser degree, decided by the means of solidification of the castings, rather than transformations occurring in the matrix, as controlled by nickel equivalent value (especially elements with high electrochemical potential).