Vibrations in engineering and technology

Viktor Matviychuk - Doctor of Technical Sciences, Professor, Dean of the Faculty of Engineering and Technology of Vinnitsa National Agrarian University (3 Soniachna St., Vinnitsa, Ukraine, 21008, e-mail: vamatv50@gmail.com).

Oleg Haidamak - Candidate of Science (Engineering), Associate Professor, Associate Professor of the Department of Electrical Engineering, Power Engineering and Electromechanics of Vinnitsa National Agrarian University .

Mykola Kolesnik is a post-graduate student of the Department of Electric Power Engineering, Electrical Engineering and Electromechanics of Vinnitsa National Agrarian University (3 Soniachna St., Vinnitsa, Ukraine, 21008, e-mail: kolisnik30@gmail.com).

The article investigates changes in the characteristics of the surface layers of parts processed by methods of surface plastic deformation (SPD). It is shown that at SPD the strength and hardness characteristics of the material increase and residual compression stresses are formed. On the basis of the study of the stress-strain state of the material at the SPD, its non-monotonicity is established, which is manifested in the gradual change of sign of the components of deformations and stresses. In this regard, a tensor-nonlinear damage accumulation model was used to evaluate the deformability of the material, which takes into account the directional nature of the damage and the anisotropy of the plasticity of the deformed metal. Based on this model, an expression was obtained to determine the plasticity resource used in the case of multi-stage SPD. According to the results of the calculations, it is established that the maximum plasticity resource used in the SPD is at a depth of approximately 0.1 of the diameter of the plastic footprint of the tool, and destruction at full exhaustion of the plasticity resource occurs in the form of peeling of thin plates of appropriate thickness. Recommendations for displacement of the most reinforced layers to the surface of the workpiece are developed, as well as recommendations for limiting deformation by the amount of plasticity resource used. The conducted research allows to assign the optimal modes of SPD at the stage of technological process design.

A device for cold gas-dynamic spraying was developed and the possibility of creating antifriction sections using it was investigated. Graphs of dependence of geometrical parameters of the deposited layer on the sputtering distance are constructed and methods and schemes of preparation for deposition of the surface of the workpiece using SPD methods are developed. Experimental cold gas-dynamic spraying was carried out and optimal parameters of the process of spraying of antifriction layers of bronze and metal polymers (pressure, and the temperature of the compressed air and the temperature of the workpiece) on the formed roller surface were determined. A new concept of increasing the contact strength and durability of friction pairs is proposed.

1. Kaletnik G. M., Chausov M. G., Shvayko V. M. (2013) Fundamentals of Engineering Methods of Strength and Stiffness Calculations: Kyiv: Height-Tech Press. [in Ukrainian].

2. Odintsov L.G. (1987). Strengthening and finishing of parts by surface plastic deformation: Handbook .- M .: Mechanical Engineering. [in Russian].

3. Matviichuk V. A., Aliiev I. S. (2009). Sovershenstvovanye protsessov lokalnoi rotatsyonnoi obrabotky davlenym na osnove analyza deformyruemosty metallov. Kramatorsk. [in Ukrainian].

4. Mikhalevich V. M. (1998) Tensor models of damage accumulation: "UNIVERSUM - Vinnytsia". . [in Ukrainian].

5. Alkhimov A.P., Klinkov S.V., Kosarev V.F., (2010) Fomin VM Cold gas-dynamic sputtering. Theory and Practice. M: PHYSMATLITE. [in Russian].

6. Device for gas-dynamic coating with radial flow of powder material: Pat. 110552 Ukraine, IPC6 С23С24 / 00 № а 201405543; claimed 05/23/14; publ. 01/12/16, Bul. №1. 12 sec. [in Ukrainian].

7. Gaidamak O. L. Savulak V. I. (2018). Experimental study of cold gas-dynamic coating process and calculation method of its modes. Bulletin of Vinnitsa Polytechnic Institute, 4, 88-94. [in Ukrainian].

8. Gaidamak OL, Savuliak VI (2016) Investigation of the properties of coatings created by cold gas-dynamic deposition of PA-4 powder. Bulletin of the Donbass State Machine-Building Academy, 2 (38), 70-73. [in Ukrainian].