FINITE ELEMENT ANALYSIS OF THE POROUS COATING IN HIP-JOINT PROSTHESIS

Nikitsin A.V., Graduate Student of the Department of Bio- and Nanomechanics, Belarusian State University, Minsk, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it.
Mikhasev G.I., Doctor of Physical and Mathematal Sciences, Professor, Head of the Department of Bio- and Nanomechanics, Belarusian State University, Minsk, Republic of Belarus
Maslov A.P., Candidate of Medical Sciences, Head of the Orthopedic and Trauma Unit no. 1, Minsk Regional Clinical Hospital, Minsk, Republic of Belarus

The finite element model of the cementless femoral stem was used to calculate the main stresses of the bone-implant interface. Assuming the rigid contact between porous coating and bone tissue, three different implant designs were analyzed: smooth shape implant, implant with two porous inserts and when 2/3 of the implant was coated by the porous titanium. Results showed that enlargement of the porous coating increases the stresses within proximal femur and reduces the stresses in diaphysis.

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EFFECT OF PROCESSING CONDITIONS ON POWER OF GRINDING BY POLYMERIC-ABRASIVE DISK BRUSHES

Ustinovich D.F., Candidate of Technical Sciences, Scientific Secretary of the Physico-Technical Institute of the NAS of Belarus, Minsk, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it.
Pribylsky V.I., Candidate of Technical Sciences, Associate Professor, Leading Researcher, Joint Institute of Mechanical Engineering of the NAS of Belarus, Minsk, Republic of Belarus

The paper presents the results of investigating the power consumption required for carrying out the processing of parts made of constructional steels 45 and 12Х18Н10Т by polymeric-abrasive disk brushes. It is established that changing the effective power of processing is substantially affected by increase of cutting speed, powder graininess of abrasive fiber modifier and radial deformation as well as kind of processed material and LSS use. It is shown that increase of cutting speed, graininess and radial deformation of tool contribute to increasing effective processing power. The empirical dependences obtained enable analytical determination of values of processing power and its components depending on technological process parameters.

• Ustinovich D.F. Finishnaja obrabotka polimerno-abrazivnymi volokonnymi kompozitami [Final machining with polymer-abrasive fiber composites]. Inzhener-mehanik [Mechanical engineer], 2002, no. 4(17), pp. 33-37.
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• Poduraev V.N. Avtomaticheski reguliruemye i kombinirovannye processy rezanija [Automatically adjustable and combined cutting processes]. Moscow, Mashinostroenie, 1977. 304 p.
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MODELING STRESS-STRAIN STATE OF ROLLER/RING TRIBO-FATIGUE SYSTEM

Sherbakov S.S., Candidate of Physical and Mathematical Sciences, Associate Professor of the Department "Theoretical and Applied Mechanics", Belarusian State University, Minsk, Republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it.
Borodako S.M., Employee of the Laboratory of Wear-Fatigue Tests, PO "Gomselmash", Gomel, Republic of Belarus

Roller/ring tribo-fatigue system which is used in wear-fatigue tests as the model of wheel/rail system is considered. In this system as well as in wheel/rail system stress-strain state is defined by interaction of contact and volume deformation of one of the system elements. These loads in the roller/ring system are defined by single compressive force. Results of finite element simulation of stress-strain state of roller/ring system are presented. Significant change of contact parameters and stresses distributions in this system due to the bending of the ring comparing to the contact pair is shown.

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• Sosnovskij L.A., Matvecov V.I., Shherbakov S.S. K razrabotke metoda ispytanij rel'sov na modeljah v uslovijah, blizkih k jekspluatacionnym [To the development a method of testing rail on models under conditions close to operational]. Tr. Mezhdunar. nauch.-tehn. konf. “Sovremennye problemy putevogo kompleksa. Povyshenie kachestva podgotovki specialistov i urovnja nauchnyh issledovanij” [Proc. Int. Sci.-Techn. Conf. “Modern problems of track complex. Improving the quality of specialists training and the level of scientific research”]. Moscow, 2004, vol. IV. 37 p.
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• Shherbakov S.S., Borodako S.M. Komp'juternoe modelirovanie naprjazhenno-deformirovannogo sostojanija modelej sistemy koleso/rels [Computer modeling of stress-strain state of the model wheel/rail]. Tr. VI Mezhdunar. simpoziuma po tribofatike (ISTF 2010) [Proc. VI Intern. symposium on tribo-fatigue (ISTF 2010)]. Minsk, BGU, 2010, vol. 2, pp. 227-232.

STRUCTURAL STRENGTH OF ALUMINUM-CONTAINING STEELS IN CONSTRUCTIONS OF LARGE-DIMENSION NITRIDED INTERNAL GEARS

Kharitonchik D.I., Deputy General Director of PO "BelAZ" - JSC "BelAZ" in quality, Zhodino, republic of Belarus, This email address is being protected from spambots. You need JavaScript enabled to view it.">This email address is being protected from spambots. You need JavaScript enabled to view it.

In the article it is considered the scientific and practical aspects of structural strength of modern large-dimension internal gears made of steel, containing aluminum up to 2 %. Calculated dependences required for production of gears for planetary gearbox are specified. The results of bench and operation tests of large-dimension gears made of generally known and new aluminum-containing steels are provided. Guidelines for application of steels, ensuring accident-free operation of gears at long-distance running of auto vehicles are given. The achieved solutions are grounded on the phenomenon of segregation (concentration), studied for the first time, and interaction of alloying and impurity elements on the boundary and near-border zone of grain volumes, forming grain boundary dislocation, as well as strength and technological properties of structural steels.

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