Аннотация:The paper presents the results of metallographic studies, spectroscopy and tribological tests of aluminum–silicon alloy samples with various modifiers: industrial silumin AK21M2.5H2.5, AK21M2. 5H2.5 modified P + Ce, AK21M2. 5H2. 5 + 0.08% P + 0.6% Ce (Tape), AK21M2.5H2.5 + 0.08% P (Tape), AK21 M2. 5H2.5 + 0.08% P + 0.6% Ce (Foil). The tests were carried out according to two schemes: “plane (test sample) – ring” and “flat sample along the forming surface of the rubber disc”. The dependences of the change in the coefficients of friction on the load and the speed of movement, the dependence of the specific load of the jamming of the friction pairs on the speed and intensity of wear of the samples at a constant sliding speed of 0.59 m/s, and the pressure in the friction pair of 1.1 MPa are obtained. According to the test results, in the samples of the initial material AK21M2,5H2,5 and modified P + Ce, the setting moment in the friction pair with steel occurred at a speed 1.5–2 times lower than in the other samples at equal pressure. In terms of wear intensity, these alloys have a wear resistance 1.5 times lower than other materials under study. According to the results of abrasive wear, the sample of the starting material AK21M2. 5H2.5 had a wear significantly higher than the other alloys. Metallographic studies, spectroscopy results, integrated spatial and frequency characteristics, and test results provide a clear understanding of how the size and geometric shape of silicon particles in an alloy affects the hardness and wear resistance of the materials under study.