Vol 36, No 8 (2016)

By the analysis of plastic deformation with ultrasound treatment, analytical formulas are obtained for the strain rate and stress rate and the deformation of the thread profile is estimated. The use of ultrasound treatment to correct the geometric parameters of the thread and strengthen its surface is considered. The effectiveness of ultrasound treatment of threads is confirmed.

A mathematical model for determining the basing errors in coordinate measurements of gears by means of pins is formulated on the basis of a best-fit algorithm.

The forces in a model mechanism with parallel cranks (a KHV planetary mechanism) are analyzed, with identification of the static indeterminacy of the system by means of contact-interaction theory.

The high-temperature gas corrosion of intermetallic alloys based on titanium aluminides is investigated at 800°C after calorizing. The composition and structure of the surface layer are studied after the tests

By multifractal parameterization of the contact surfaces of the tool and the supporting surface of the chip in the cutting process, the relation of the fractal dimensionality with the tool’s wear rate and the informational entropy is established. In addition, the nonlinear dependence of the tool life on the cutting speed is found. A diagnostic system for monitoring the dynamic stability of the cutting system and the tool wear is proposed.

An information and measuring system for phase–chronometric lathe diagnostics is described. The system hardware is specified. The results of mathematical modeling are compared with experimental data.

Virtual debugging of control programs for numerically controlled metal-cutting machines is considered. The milling of slots in a gas-turbine compressor disk is simulated on a three-dimensional copy of a DMU 50 numerically controlled five-coordinate vertical-milling machine. The text of the control program is verified and optimized.

A hard-alloy end mill capable of faster machining of curvilinear surfaces — in particular, in the production of gas-turbine blades — is proposed. Options for improving the performance of hard-alloy tools on the basis of ultrasound are discussed.

Ultrasonic and acoustic axial spindle oscillations improve the productivity and product quality in machining, reduce the cutting forces, and increase the tool life in the grinding, milling, and boring of structural components, including those made from materials that are hard to machine. Industrial prototypes of motorized spindles with axial spindle oscillations have been developed by specialists at Siberian Federal University and AO NPP Radiosvyaz and patented in Russia. These spindle units include contactless hydrostatic bearings, a resonant-frequency generator (a piezo generator for ultrasonic spindles and a hydromechanical generator for acoustic spindles), and a local concentrator for the spindle’s longitudinal intrinsic waves.

In mining, it is important to ensure effective monitoring and to improve the precision of the geophysical instruments used in mineral prospecting. The electrophysical and structural optimization of instruments for monitoring the neutron yield of borehole generators in neutron–neutron logging systems is considered. Diamond detectors have been developed and successfully employed for this purpose. The expanded use of diamonds, especially in instruments, improves the utilization of natural resources. In regular equipment for monitoring the neutron yield of borehole generators in neutron–neutron logging systems, the consequences of introducing Russian diamond detectors are studied. Specifically, the influence of the ambient parameters on the borehole instrument (temperature stability of the diamond detector in the range 20–140°C) is determined; and the linearity of the conversion characteristic of the fast-neutron monitor in the system is investigated by measuring the fluctuation of the output-signal amplitude in the range 20–140°C.