Abstract
Purpose. Research aims to study the influence of alloying elements on the properties of steels contributing to the increased sound energy dissipation and reduced acoustic emission in order to develop alloys for the manufacture of mining equipment parts operating in impact mode (drill string and drill bit housing. Methods. Six alloys were developed during the research based on standard steels. Samples were melted in LPZ-1-67 high-frequency induction furnace at a melting temperature of 1700°C. All the samples were made in the form of 50×50×5 mm plates. KazNTU-2017 setup was used to study the impact noise level. The sound signal was calibrated using a ZG-10 generator. The results were corrected for atmospheric pressure using a PF-101 piston telephone. The temperature and humidity in the laboratory were maintained at a constant level. Acoustic measurements were made five times, with subsequent averaging of the results. Findings. The developed alloys No. 4 and No. 6 have increased dissipative characteristics, which allows them to be classified as “quiet” steels. This is due to the increased graphite and ferrite content in their structure, which promotes effective absorption of sound energy. Alloy No. 3 has medium dissipative properties due to the presence of residual cementite in the structure. Originality. Alloys No. 3, 4 and 6 have been found to have a damping logarithmic decrement (δ) of 2 times higher, relative scattering (ψ) of 3 times higher, and internal friction (Q-1) also 3 times higher than that of standard steel grades used in mining machine parts. Practical implications. The developed alloys No.3, No.4 and No.6 are recommended to be used in the manufacture of mining equipment parts. Their increased dissipative properties reduce the noise level of drill string and drill bit housing by 10-12 dBA, help increase the service life of units, as well as improve the working conditions of workers in the mining industry.