Metal products for the metallurgical and machinery industries must meet high requirements in terms of their performance, including reliability, accuracy, durability and fatigue strength. It is also important that materials commonly used to manufacture such products must meet specific requirements. Therefore, various techniques and technologies for modifying the surface layer are becoming more and more widely used. These include burnishing, which may be dynamic or static. This article studies the process of slide burnishing of surfaces of cylindrical objects. The burnishing was performed using a slide burnisher with a rigid diamond-tipped clamp on a general-purpose lathe. The tests were performed for corrosion-resistant steel X2CrNiMo17-12-2. The aim of the research was to determine the impact of changes in burnishing conditions and parameters—feed rate, burnisher depth and burnishing force at a constant burnishing speed—on the surface roughness and hardness. Additionally, the microstructure was assessed in the critical areas: the surface and the core. Another phenomenon observed was surface cracking, which would be destructive due to the occurrence of indentation. In the paper, it was stated that the microstructure, or rather the grains, in the area of the surface layer was oriented in the direction of deformation. It was also observed that in the area of the surface layer, no cracks or other flaws were revealed. Therefore, slide burnishing not only reduces the surface roughness but hardens the surface layer of the burnished material.

The aim of the research was to determine the possibility of producing and using layered composites made of aluminum and magnesium alloys Al1050-AZ31-Al1050. The use of layered composites often results from economic conditions. The work analyzed the current research, technological and production...

In this paper, the effects of 4 wt.% of silicon on the microstructure and mechanical properties of AM50 magnesium alloys fabricated by the casting method are presented. New AM50/Si material and the base AM50 alloy were gravity cast into a metal mould under the same conditions for comparison. Analyses of the alloys’ microstructures were carried out by light microscopy (with differential interface contrast), scanning electron microscopy (with an energy dispersive X-ray spectrometer), as well as X-ray diffraction (XRD). In as-cast conditions, both materials were composed of α-Mg solid solution, α + γ eutectic (where γ is Al₁₂Mg₁₇), Al₈Mn₅ intermetallic phases and discontinuous γ precipitates. The AM50/Si material also consisted of the Mg₂Si phase. This structural constituent appeared in the form of primary crystals with regular polygonal morphology and an α + Mg₂Si eutectic in the form of “Chinese script”. In the microstructure of the AM50/Si material, the Mn₃SiAl₉ ternary phase was also identified. The detailed analyses presented in this paper revealed that the new ternary Mn₃SiAl₉ structural compound caused a reduction in the volume fraction of the Al₈Mn₅ phase but did not completely replace it. These two phases formed competitively. The fabricated material exhibited higher tensile and compression strength as well as yield strength in comparison with the AM50 alloy. Additionally, analyses of the fracture surfaces of the AM50/Si material carried out using scanning electron microscopy (SEM) were presented.

This article presents the research results on the influence of heat treatment of chromium steel, used in the production of drill bits, on their mechanical properties and operational safety. The analyses revealed that the steel used in manufacturing the studied drill bit underwent hardening and tempering processes, which affected its structure and hardness. The presence of tempered martensite and manganese sulfides was observed, which, although not having a destructive impact on the steel’s properties, may limit the formation of undesirable iron sulfides. Additionally, a layer with reduced hardness was identified on the working surface of the drill bit, suggesting the possibility of tool overheating during operation. During the tool’s use, complex mechanical stresses, such as torsional, compressive, and bending stresses, may accumulate in areas prone to damage, especially at the interface between the tooth and the drill bit shank. The article emphasizes the importance of proper tool usage, including adjusting pressure and drilling angle and maintaining optimal operational conditions to ensure safety and durability. The research findings aim to enhance workplace safety and improve the performance of cutting tools in materials engineering.