Showing papers by "Andrey V. Filippov published in 2016"
10 Nov 2016
TL;DR: In this paper, deformation and fracture tensile studies on orientation dependence of 1570C aluminum alloys with respect to rolling direction have been carried out and the viscous fracture mechanism is more inherent to the samples with orientation transversal to the rolling direction.
Abstract: Both deformation and fracture tensile studies on orientation dependence of 1570C aluminum alloys samples with respect to rolling direction have been carried out. As revealed, the viscous fracture mechanism is more inherent to the samples with orientation transversal to the rolling direction while samples oriented along the rolling direction revealed quasi-brittle areas on the fracture surfaces. Despite practically the same level of the yield stress there is 10% difference I the ultimate stress.
17 citations
01 Apr 2016
TL;DR: In this article, the authors presented results of a study of the process for a dry friction metal-polymer couple on scheme disc-finger and showed that increasing pore's diameter caused a reduction of the friction coefficient and downturn its magnitude vibrations.
Abstract: The article is presented results of a study of the process for a dry friction metal-polymer couple on scheme disc-finger. Track membrane from polyethylene terephthalate was a research material. Membrane had pores with 0.4 and 0.8 μm diameters. The effect of the sliding velocity for membranes with pores of 0.8 microns was determined. Research was shown that increasing pore's diameter caused a reduction of the friction coefficient and downturn its magnitude vibrations. The study showed that track membrane have adequate resistance to wear and can be successfully used in surgical procedures in the layers of the cornea.
6 citations
01 Apr 2016
TL;DR: In this paper, the effect of rake angle and cutting edge angle has been studied for OT4 titanium alloy machining with cutting edges of various geometry parameters and the results showed that increasing the angle of the cutting edge inclination results in a change the mechanism of chip formation.
Abstract: The paper presents experimental studies of OT4 titanium alloy machining with cutting edges of various geometry parameters. Experiments were performed at a low speed by the scheme of free cutting. Intensity of plastic shear strain was set for defining of cutting edge geometry effect on machining. Images of chip formed are shown. Estimation of strain magnitude was accomplished with digital image correlation method. Effect of rake angle and cutting edge angle has been studied. Depth of deformed layer and the area of the plastic strain is determine. Results showed that increasing the angle of the cutting edge inclination results in a change the mechanism of chip formation.
5 citations
01 Aug 2016
TL;DR: The results of experimental research into dry sliding friction of Hadfield steel single crystals involving registration of acoustic emission are presented in this article, where the relationship of the acoustic emission waveform envelope to the changing friction factor is revealed.
Abstract: The results of experimental research into dry sliding friction of Hadfield steel single crystals involving registration of acoustic emission are presented in the paper. The images of friction surfaces of Hadfield steel single crystals and wear grooves of the counterbody surface made after completion of three serial experiments conducted under similar conditions and friction regimes are given. The relation of the acoustic emission waveform envelope to the changing friction factor is revealed. Amplitude-frequency characteristics of acoustic emission signal frames are determined on the base of Fast Fourier Transform and Short Time Fourier Transform during the run-in stage of tribounits and in the process of stable friction.
5 citations
10 Nov 2016
TL;DR: In this article, the properties of both pure and chopped carbon fiber reinforced polyetheretherketone samples have been carried out and it was shown that the reinforcement resulted in increasing the elasticity modulus, compression and tensile ultimate strength by a factor of 3.5, 2.9 and 2.8, respectively.
Abstract: Mechanical properties of both pure and chopped carbon fiber reinforced polyetheretherketone samples have been carried out. It was shown that the reinforcement resulted in increasing the elasticity modulus, compression and tensile ultimate strength by a factor of 3.5, 2.9 and 2.8, respectively. The fracture surfaces have been examined using both optical and scanning electron microscopy.
4 citations
10 Nov 2016
TL;DR: In this paper, the influence of friction-induced adhesion of metal to the tool on the formation of surface topography under nanostructuring burnishing was studied using both experimental and theoretical methods.
Abstract: In the paper the influence of friction-induced adhesion of metal to the tool on the formation of surface topography under nanostructuring burnishing was studied. A comprehensive approach, including both experimental (optical microscopy and profilometry) and theoretical (computer-aided simulation) methods was used. The results showed a direct connection between values of adhesion strength of materials in contact with the workpiece surface pattern quality caused by the tool movement. Results of the experimental and theoretical study are in good agreement and allow us to identify the reason of regular profile forming during surface burnishing.
3 citations
TL;DR: In this paper, the microstructural defect of additive manufactured 3-component carbon fiber reinforced polymer (CFRP) composites has been studied using computed microtomography, and defects typical for this type of composites such as delamination in polymer matrix and between fibers in a bundle, fiber breakage have been obtained.
Abstract: The microstructural defect of additive manufactured 3-component carbon fiber reinforced polymer (CFRP) composites has been studied using computed microtomography. The samples have been prepared using a 3D-printing process developed at Skolkovo Institute of Science and Technology, Russia. The research procedure has been described and internal defects of the fiber composite material have been detected and analyzed using a 3D image reconstructed from a number of cross section views. The defects larger 50 μm have been detected using the computed microtomography test. Defect-free images and defects typical for this type of composites such as delamination in polymer matrix and between fibers in a bundle, fiber breakage have been obtained.
3 citations
TL;DR: In this paper, the modal analysis procedure and the results obtained on a three-component 3D-printed carbon-fiber reinforced composite (CFRC) are presented, where different eigenoscillations waveforms possess different sensitivity of amplitude frequency response to structural defects of the composite.
Abstract: Both modal analysis procedure and the results obtained on a three-component 3D-printed carbon-fiber reinforced composite (CFRC) are presented. Experimental modal analysis of on the composite has been carried out to obtain the dynamic behavior characteristics. As revealed, the different eigen-oscillations waveforms possess different sensitivity of its amplitude frequency response to structural defects of the composite. For the similar waveforms we observed the differences in eigen-oscuillation frequencies, vibration velocities and damping factors which can be caused by the presence of numerous defects homogeneously distributed in one of the samples.
3 citations
10 Nov 2016
TL;DR: In this paper, the microtextured dotted, banded and overlapped areas on the surfaces of high-speed steel samples have been examined using laser scanning microscopy for the microtexture pattern and roughness.
Abstract: Microtexturing the metal cutting tool surfaces is a novel technique intended for enhancing the workability of these tools. The microtexturing is used in machining the titanium alloys for air-space applications for reducing the adhesion wear of metal cutting blades. This paper is focused on forming the microtextured dotted, banded and overlapped areas on the surfaces of high-speed steel samples. The treated areas have been examined using laser scanning microscopy for the microtexture pattern and roughness. It has been shown that the microtextured surfaces obtained on the high-speed steel samples were free of cracks. Surface pattern and roughness of all three microtextured areas have been examined and analyzed.
2 citations
10 Nov 2016
TL;DR: The results of the tensile tests carried out both on AMg5 (5083) aluminum alloy samples base and those obtained using friction stir processing technique are reported in this paper.
Abstract: The results of the tensile tests carried out both on AMg5 (5083) aluminum alloy samples base and those obtained using friction stir processing technique are reported. The tensile test samples have been prepared from the friction stir processed plates so that their tensile axis was parallel to the processing direction. The maximum tensile strength of the processed samples was 9% higher than of the base metal. The fractographic examination shows the presence of flat areas inherent of the brittle fracture in all three friction processed samples. The load-extension curves show that friction stir processing may suppress the serrated yielding.
2 citations
10 Nov 2016
TL;DR: In this article, the results of 3D modeling and experimental modal analysis on a polymer composite framework obtained using additive manufacturing are presented, by the example of three oscillation modes, with the use of laser Doppler vibrometry.
Abstract: Additive manufacturing by 3D printing is the most advanced and promising trend for making the multicomponent composites. Polymer-based carbon fiber reinforced composites demonstrate high mechanical properties combined with low weight characteristics of the component. This paper shows the results of 3D modeling and experimental modal analysis on a polymer composite framework obtained using additive manufacturing. By the example of three oscillation modes it was shown the agreement between the results of modeling and experimental modal analysis with the use of laser Doppler vibrometry.
10 Nov 2016
TL;DR: In this article, the authors focused on conducting tribological experiments with sliding the steel samples over the surface of diabase stone sample where abrasive wear conditions of soil cutting are modeled experimentally.
Abstract: The earthmoving of permafrost soil is a critical task for excavation of minerals and construction on new territories. Failure by abrasive wear is the main reason for excavation parts of earthmoving and soil cutting machines. Therefore investigation of this type of wear is a challenge for developing efficient and wear resistant working parts. This paper is focused on conducting tribological experiments with sliding the steel samples over the surface of diabase stone sample where abrasive wear conditions of soil cutting are modeled experimentally. The worn surfaces of all samples have been examined and transfer of metal and stone particles revealed. The acoustic emission (AE) signals have been recorded and related to the results of worn surface analysis. he acoustic emission (AE) signals have been recorded and related to the results of worn surface analysis. As shown the wear intensity correlates to that of acoustic emission. Both acoustic emission signal median frequency and energy are found to be sensitiv...
13 Oct 2016
TL;DR: Polyethylene terephthalate track membrane has a great opportunity to use as a bio implant in ophthalmology’s surgery due to its physical and chemical properties and biological comparability.
Abstract: Polyethylene terephthalate (PET) track membrane (TM) has a great opportunity to use as a bio implant in ophthalmology’s surgery due to its physical and chemical properties and biological comparability. Sterilization of medical implants can change its properties and can influence on regeneration process and success of surgical treatment. We researched influence on the PET track membrane of two sterilization methods wide used in medicine. The first sterilization method was steam sterilization. The second method was γ-irradiation of Co60 radionuclide sterilization. The sterilization processes influence on the track membrane properties was assessed by surface topography analysis, IR Fourier spectroscopy, wetting angle and surface energy of TM surface measurement.
10 Nov 2016
TL;DR: In this paper, the applicability of acoustic emission, accelerometers and eddy current sensors for measuring the workpiece elastic deflection exerted by the cutting force has been discussed together with the analysis of measurement errors.
Abstract: Monitoring of the edge clamped workpiece deflection during milling has been carried our using acoustic emission, accelerometer and eddy current sensors. Such a monitoring is necessary in precision machining of vital parts used in air-space engineering where a majority of them made by milling. The applicability of the AE, accelerometers and eddy current sensors has been discussed together with the analysis of measurement errors. The appropriate sensor installation diagram has been proposed for measuring the workpiece elastic deflection exerted by the cutting force.
10 Nov 2016
TL;DR: In this article, the results of experiments with high load and sliding speed sliding conditions on tribologically mated pairs such as steel 1045/steel 1045 (test 1, test 2) and Hadfield steel/basalt (test 3) have been carried out in order to identify their response in terms of the acoustic emission and vibration signals.
Abstract: The results of experiments with high load and sliding speed sliding conditions on tribologically mated pairs such as steel 1045/steel 1045 (test 1), steel 1045/basalt (test 2) and Hadfield steel/basalt (test 3) have been carried out in order to identify their response in terms of the acoustic emission and vibration signals. The steel to rock and rock to steel transfer has been revealed by examining the worn surfaces of both steel and rock samples with the use of laser scanning microscopy. The AE signal characteristics have been determined for the tribological pairs studied. The dynamics of sliding has been evaluated by measuring the vibration accelerations. Relationship between wear mode and either acoustic emission signal or vibration signal has been established. The minimal vibration oscillations amplitude and acoustic emission signal energy have been found out in sliding Hadfield steel/basalt pair.
01 Aug 2016
TL;DR: In this article, the influence of different combinations of wheels on roughness of the inserts front and rear surfaces and quality of cutting edge was studied with the help of laser confocal microscopy.
Abstract: Engineering process preparation requires proper preparation of cutting tools. It influences not only the performance of the tools but also the quality of workpiece surface machining. One of the promising environmentally friendly trends of mechanical treatment is grinding without using lubricating cooling liquid. This method can considerably influence the quality of cutting tools grinding. Smoothing skiving turning is an effective treatment method providing high efficiency and workpiece quality. Proper preparation of cutting edges is especially important in this process. For that purpose we have carried out a research in grinding changeable carbide inserts for skiving turning by means of grinding wheels with different grain size. The influence of different combinations of wheels on roughness of the inserts front and rear surfaces and quality of cutting edge was studied with the help of laser confocal microscopy.