This paper presents the information about manufacturing processes of hybrid composites with aluminum alloy matrix containing glassy carbon as a solid lubricant. Two methods have been described: the method based on mixing glassy carbon and ceramic particles with a liquid metal matrix; and the precursor method. In the precursor method, carbon is introduced into a composite with the application of liquid precursor and porous ceramic foams. It is then followed by precursor pyrolysis where, as the result, glassy carbon is obtained. Ceramic foams help liquid precursor penetrate the ceramic spheroid pores by forming a thin film of glassy carbon on their walls. Composites produced by the both methods feature good tribological properties. Sliding friction coefficient in air of the new obtained by mixing method composite against cast iron (μ = 0.08 − 0.17 at wearing in and 0.12 after wearing in by reciprocating sliding and 0.14 − 0.17 by rotating sliding) is much lower than in the case of composite containing only ceramic foam as a reinforcing phase (μ = 0.28 − 0.36 by reciprocating sliding and 0.28 − 0.40 by rotating).

Tribological Properties of Rail Steel in Straight Moderately Loaded Sections of Railway Tracks: The paper describes the examination results of tribological properties of three types of steels used and suggested for rails manufacturing. The tests concentrated on loads, sliding and rolling speeds similar to those occurring in real conditions i.e. rolling track operation. Average loaded conditions were assumed and applied at straight railway track sections. Slight track declivity and high/low speeds of locomotive were considered. "Amsler" stand was used for laboratory tests. Three types of steels i.e. two pearlitic steels: WHT - without heat treatment, HT - with heat treatment (with the microstructure of fine pearlite) as well as one bainitic steel suggested for rail production have been tested. The measurements of wear, hardness, friction coefficient as well as structural changes at surface layers of the tested rollers have been performed during the test.

The paper presents the influence of the nickelising parameters on the structure and tribological properties of composite coatings AHC+Ni, including nickel nanowires, which have been obtained by nickelising of anodic hard coatings on aluminium alloys. The influence of nickelising parameters on the utility properties of the coatings is presented in the diagrams. The absorbability and roughness R_a of coatings have been chosen as the utility properties important from tribological point of view. Coatings with high absorbability and low roughness feature good tribological properties, for example, during cold start of piston machines. Nickel precipitates and nanowires enable sliding of cast iron against aluminium oxide. On the basis of the elaborated diagrams, the potential user can select nickelising parameters to produce coatings featuring the required properties.

The article presents the influence of aluminium oxidation parameters on the insulating properties of oxide coatings on aluminium strips of electrical windings. The effect of H₂SO₄ electrolyte concentration, its temperature and anode current density on the value of unit breakdown voltage was determined. A significant influence of the contact surface area of the measuring electrode with the coating on the breakdown voltage was found. The error of breakdown voltage measurement does not exceed 5% if the contact surface area of the electrode is a minimum of 10 cm². Constant and varying components of the breakdown voltage were distinguished. The constant component is up to 55% of the value and depends mainly on the thickness of the coating. The varying component depends on the surface topography of the oxide, mainly on the number of roughness peaks per unit area.