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Al-Mg alloys are characterized by permanent solid solution hardening and can additionally be work-hardened. The high mechanical properties of Al-Mg alloys with above-standard Mg content obtained after plastic deformation processes decrease over time. The addition of minor alloying elements like Er or Zr is an alternative method to improve the durability of mechanical properties and increase the strength of Al-Mg alloys due to densely and evenly distributed dispersoids being formed. In this paper, Al-Mg alloys with above-standard Mg content (7 wt.%) and Zr and Er micro-alloying elements and their influence on the microstructure and durability of the mechanical properties were examined. The cast ingots of AlMg7 alloys were characterized by a smooth surface without cracks. The plastic deformation process in a static compression test resulted in an about 60 HBW increase in the Brinell hardness of all the deformed alloys relative to casting. It was revealed that the addition of Er and Zr significantly improved the mechanical properties and durability of the mechanical properties of the Al-Mg after annealing. The addition of Er or Zr slightly restrained the decrease in the Brinell hardness after annealing but did not inhibit it. [ABSTRACT FROM AUTHOR]

A hard anodic oxide coating's characteristic porous structure allows for its modification by the incorporation of nanoparticles. However, achieving an appropriate microstructure requires an optimal pore arrangement and shape, which is influenced by the electrolyte composition, current densities, temperature, and processing time. To achieve pores with a diameter of about 50 nm and the most regular structure, a range of these parameters were tested. Using a two-stage manufacturing process had a beneficial effect on increasing the microporosity of the coating. The addition of phthalic acid at 0 °C did not increase the pore diameter, but allowed for the process to be carried out at higher temperatures. However, the coating produced at 20 °C had a larger pore diameter, but numerous defects. The coating obtained from the three-component solution had the most regular structure, but the smallest pore diameter. [ABSTRACT FROM AUTHOR]

Due to wear and improper operation, many machine parts become useless, which is why issues of friction and wear remain constantly relevant across all industrial sectors. This paper presents the results of research on the microstructure and properties of a nanostructural composite coating containing solid lubricant. The coating was deposited from a mixture of nanostructural WC-12Co powder and nanostructural Fe3O4 powder using HVOF spraying. Despite significant differences in grain size and density of both powders, the deposited coating consisted of WC-12Co matrix containing evenly distributed Fe3O4. The XRD analysis of the coating confirmed the presence of both components and the presence of W2C, which resulted from the decarburization of WC due to the high temperature during the spraying process. Furthermore, the microstructure analysis of the coatings confirmed that they contained both nanostructural WC and Fe3O4 grains that were present in the feedstock. The coefficients of friction, microhardness, and wear of the nanostructured composite coatings were determined using an experimental binomial program. Based on the ANOVA conducted, it was determined that the most significant impact on the friction coefficient is the Fe3O4 content in the sprayed mixture, while the oxygen to propane ratio affects the microhardness. For the wear of nanostructural composite coatings, the most important parameter is the spraying distance. [ABSTRACT FROM AUTHOR]

Cold-sprayed composite coatings have several advantages; however, some properties, such as hardness and abrasion resistance, are lower than those in plasma- or HVOF-sprayed deposits. This work showed that the use of surface diode laser processing allowed the development of (Cr3C2-25(Ni20Cr))-(Ni-graphite) cermet coatings with good adhesion to the steel substrate, and increased properties in the near-surface zone, below which the properties of cold-sprayed coatings were retained. Studies of the microstructure in the micro/nanoscale of the laser-treated coatings showed strong grain refinement after surface treatment. Cr7C3 carbide of various shapes and sizes was formed in the structure; while, a several hundred nanometre layer of Cr2O3 oxide appeared on the coating surface. The changes occurring in the microstructure have resulted in increased mechanical and tribological properties of the laser-treated zone of deposits. [ABSTRACT FROM AUTHOR]