IMPROVING THE PERFORMANCE CHARACTERISTICS OF MACHINE PARTS BASED ON THE COMBINED INFLUENCE OF STRONG MAGNETIC FIELDS

Magnetic treatment is a promising method of hardening. Metal exposed to alternating magnetic fields changes the performance properties of the surface layer of a combination of magnetic and ultrasonic effects, provides a combined method of processing and strengthening surfaces of machine parts, which eliminates the main disadvantages of magnetic and electrical hardening — instability of physical and mechanical properties of this layer with detail. The purpose of the work is to investigate the possibility of improving the performance of machine parts based on the combined effect of strong magnetic fields. The study of the use of a uniform flux of magnetic fields generated by powerful permanent magnets was performed to affect the material volume of non-grinding plates of the cutting tool CNMG_120508E-M. The effect of uniform magnetic flux is initiated as a result of resonant oscillations of the sample caused by broadband exposure of equal amplitude by means of a "white noise" generator and a piezo emitter. The authors found that as a result of volumetric strengthening of non-grinding plates of carbide cutting tools, by exposure to polyfrequency oscillations in the form of a broadband frequency spectrum of equal amplitudes, a significant reduction in dimensional wear of the plates is achieved. Adding mechanical vibrations to the samples in a uniform constant magnetic field allowed to achieve volumetric hardening of the samples from 150 HB to 240 ÷ 250 HB, ie 60 ÷ 65% in 10—12 minutes, which is the hardening of the samples by 5—6% in one minute. The work on determining the relationship of changing properties with processing time, frequency range, amplitude and other modes to find the optimal values ​​of processing parameters, has great prospects for the ability to obtain a set of performance characteristics, control external and internal properties of products.

Bandoneon!

Bandoneon! (a combine), performed in October 1966 as part of the 9 Evenings: Theatre and Engineering, has been regarded as Tudor’s first work as a composer. However, the conception of this piece was not only directly influenced by two other amplified bandoneon pieces he realized in the same year, Gordon Mumma’s Mesa and Lowell Cross’s Musica Instrumentalis, but had also started off as a realization of a “Mobius-Strip” composition by Mauricio Kagel. Moreover, most of the modular electronics in his setup were also used in other realizations around the same period. The true difference lies in how these common materials were used and to what ends. What the self-proclaimed effort to make a “giant white noise generator” from scratch brings to the fore is a synecdochical relationship between the modular instruments used and the larger instrumental complex they compose. The investigation of this coordination between the parts and the whole reveals a strange disappearance of an entire group of instruments considered central to the performance, a mystery that highlights the peculiar nature of Tudor’s “composition.”

Phase Congruential White Noise Generator

White noise generators can use uniform random sequences as a basis. However, such a technology may lead to deficient results if the original sequences have insufficient uniformity or omissions of random variables. This article offers a new approach for creating a phase signal generator with an improved matrix of autocorrelation coefficients. As a result, the generated signals of the white noise process have absolutely uniform intensities at the eigen Fourier frequencies. The simulation results confirm that the received signals have an adequate approximation of uniform white noise.

MAGNETIC RESONANCE PROCESSING OF MATERIALS

Acoustic devices for determining the elasticity modulus based on the measurement of the samples frequency resonant oscillation due to the sample exposure to acoustic waves with consistently changed frequencies. Objective: Development of an algorithm for increasing the hardness of materials due to magnetic resonance imaging. Materials and methods: The paper shows the possibility of using as a uniform flux to influence the volume of thematerial of the magnetic field formed by powerful permanent magnets. The process of influencing the volume of material of the experimental samples was that the effect of a uniform magnetic flux permeating the sample is initiated in a result of resonant oscillations of the sample caused by broadband exposure of equal amplitude using a “white noise” generator and a piezoelectric emitter. Results: Treatment of samples of materials placed in a uniform magnetic field, resonant polyfrequency vibrations with nanoscale amplitude in the range of 20...80 nm, allows you to change the viscosity of the material, the modulus of elasticity of the material and the hardness of material samples to improve the performance of these materials . Conclusions: Nanoscale amplitudes of natural oscillations of objects of complex shape in energy fields, which include uniform magnetic fields, can correct the physical and mechanical properties of materials of such objects in order to achieve their identity or add strictly defined properties.

A Noise Generator for Embedded Circuits Testing

This paper describes the implementation of a white noise generator to be used as the input signal of a new method for testing analog-to-digital converters (ADCs) and linear filters. The main goal of this method is to avoid the comparison of the output signal with a known and very precise reference input. The proposed white noise generator is easily implemented, with less complexity than others excitation signals. The use of noise as the input signal avoids concerns about the inherent noise present in all electronic systems. The testing technique is based on the analysis of the spectral response of the CUT output. This paper covers the generation of the excitation signal, as well as simulation and practical results are presented to prove the efficiency of the test method.