About the influence of zirconium on the damping capacity of Mn - 40 % Cu alloy in the field of amplitude-independent damping

The results of a study of the damping capacity of manganese-copper alloys based on the Mn - 40 % Cu alloy with additives (0,5 ... 1,5) % zirconium in the field of amplitude-independent damping are presented. Mn - Cu alloys with high damping capacity can be effectively used to reduce vibration and noise. Studies on the influence of a number of alloying elements on the magnitude and stability of the damping capacity of Mn - Cu double alloys in the field of small deformations of relative shear are not enough. In the article, the influence of one of these elements, zirconium, was elucidated. Mn - Cu alloys were smelted in an induction furnace. From the ingots cast into cast iron molds, samples for studies with dimensions (11 × 15 × 117) ± 1 mm were obtained by mechanical cutting. The samples were subjected to aging at a temperature of 643 K for (0,5 ... 40) hours. The damping capacity of Mn - Cu alloys (the logarithmic decrement of attenuation of oscillations) was studied for longitudinal oscillations of samples in the frequency range (14 ... 17) kHz and the amplitudes of the relative shift (1 ... 3) × 10-6. It has been established that alloying the Mn - 40 % Cu alloy with zirconium from 0,5 % to 1,5 % does not increase its damping capacity in the cast state, as well as in the cast and aged at a temperature of 643 K for 40 hours. It was found that the minimum values of the frequencies of resonant vibrations of samples of Mn - Cu alloys correspond to the maximum levels of the damping capacity of these alloys. Itʼs shown that the high damping capacity of cast and aged alloys at 643 K for 40 hours Mn - 40 % Cu, Mn - (38,5 ... 39,5) % Cu - (0,5 ... 1,5) % Zr after natural aging at 293 K for 7 months decreases by (2,0 ... 2,6) times.