Applied Engineering Letters

1-9

Authors: D. D. Trung

This paper presents a research on investigating the effect of cutting parameters on the surface roughness (Ra) and roundness error (RE) when turning the interrupted surface of 40X steel. The TiN coated high speed steel (HSS-TiN) inserts were used in this research. The cutting parameters include cutting velocity, feed rate, and depth of cut. The Box-Behnken method was applied to develop an experimental matrix with fifteen experiments. The influences of cutting parameters on Ra and RE were found using Pareto chart. Two equations that presented the relationship between Ra, RE and cutting parameters were established. These two equations were used to predict Ra and RE. Genetic algorithm (GA) was also used to determine the optimal values of cutting parameters to simultaneously ensure the minimum values of Ra and RE. The further works of this study was also mentioned in this paper.

17-24

Authors: M. A. Kuznetsov, D. P. Il’yashchenko, E. V. Lavrova, S. A. Solodsky, О. А. Podgornyh, E. V. Verkhoturova

This paper presents the results of working out the modes of obtaining micro range powders according to the developed method. It is based on the navigation on the material of the vortex plasma flows of heterogeneous plasma and synchronized high-frequency impact on the electrode. The formation of powders is derived from individual particles heated and accelerated using a high-temperature gas jet - plasma. It is obtained in a special original plasma generator by blowing the plasma-forming inert gas into an electric arc resulting between two electrodes. The possibility of obtaining powders of various sizes and chemical composition by this method on the developed technology has been established. The design of the executive equipment that implements the studied generation process of the micro-size range is best suited for steel wires. Experimental studies made it possible to determine the optimal modes for wires of various chemical composition (steel wire, with a diameter of 1.2 mm, OK Autrod 347Si with a diameter of 0.8 mm). Range of parameters and modes of actuating equipment: current of 70-80A; Plasma-forming gas pressure 0.7-0.8 atm., Wire feed rate 20-40 mm/s, the frequency of ultrasonic oscillations of 50 MHz and 100 MHz. In these conditions, powders are obtained with a dimension of 50-100 μm.

32-44

Authors: M. Stanojević, R. Tomović, L. Ivanović, B. Stojanović

Planetary gear trains have been applied for a long time in the automotive industry as an irreplaceable part of automatic gearboxes. This paper presents, based on existing research, the kinematic analysis and evaluation of Ravigneaux gear trains, effects of power flow analysis and power loss, evaluation of utility effects of energy utilization through analysis of efficiency. It also illustrates research topics that analyse technical challenges of understanding and predicting dynamics and vibrations of planetary gear trains in the process of design of their configuration, optimization of given gear trains in reference to set criteria and affirmation of validity of their constructions by prototyping and prototype testing on the test stand.