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Na osnovu potreba razvoja i istraživanja visokobrzinskih motor-vretena, može se zaključiti da je neophodan kompleksan pristup ovom sklopu kao složenom mehaničkom sistemu, koji direktno utiče na ponašanje mašine alatke u eksploataciji. Kompleksan pristup treba da omogući da se toplotno-mehaničko ponašanje mašina alatki predvidi još u fazi projektovanja. Kako su glavna vretena sa visokobrzinskim kotrljajnim ležištima još uvek najzastupljenija konstrukciona rešenja, to je pred ovaj rad postavljen zadatak da se motor-vreteno, analizira sa stanovišta toplotno-mehaničkog ponašanja, te da se kreira kompleksan toplotno-mehanički model sklopa motor-vretena. Na primeru sklopa visokobrzinskog motor-vretena, uležištenog kugličnim ležajima sa kosim dodirom, želi se eksperimentalnim ispitivanjem proveriti definisani model za identifikaciju toplotno-mehaničkog ponašanja i analizirati uticaj temperature na njegove statičke i dinamičke karakteristike. Takođe se kroz rad analiziraju uticaji različitih fluida za hlađenje motor-vretena, kao i uticaj količine protoka fluida kako za hlađenje statora, tako i za hlađenje i podmazivanje ležaja. Polazeći od ovako definisanog globalnog zadatka, istraživanja u radu su izložena u okviru devet poglavlja., Based on the needs of development and research of high-speed motor-spindles, it can be concluded that a complex approach to this assembly is necessary as a complex mechanical system, which directly affects the behavior of the machine tool in exploitation. A complex approach should enable the thermal-mechanical behavior of machine tools to be predicted at the design stage. As the main spindles with high-speed rolling bearings are still the most represented construction solutions, the task of this work is to analyze the motor-spindle from the point of view of thermal-mechanical behavior, and to create a complex thermal-mechanical model of the motor-spindle assembly. On the example of a high-speed motor-spindle assembly, supported by ball bearings with oblique contact, it is desired to verify the defined model for the identification of thermal-mechanical behavior and analyze the influence of temperature on its static and dynamic characteristics through experimental testing. The work also analyzes the influence of different fluids for cooling the motor-spindle, as well as the influence of the amount of fluid flow both for cooling the stator and for cooling and lubricating the bearings. Starting from the global task defined in this way, the research in the paper is presented in nine chapters.

In this thesies was conducted an analysis of the static and dynamic behavior of ball bearings, with special care on four-point contact ball bearing. The main goal of the research in this paper was to develop a software solution for the analysis of static and dynamic behavior of the deep grooved ball bearings and four-point contact ball bearing, apropose identification of behavior in exploations and determination fatique life of bearings using mathematical models. Experimental bearing test was performed, in order to verify the results obtained by applying the developed mathematical models, as well as by applying general - purpose software systems, which are based on the finite element method. The experimental test was performed for two types of bearings: for the deep grooved ball bearing FKL 6006 and the four-point contact ball bearing FKL LSQFR 308.

Predmet ove doktorske disertacije je analiza dinamičkog ponašanja kotrljajnih ležaja primenom veštačkih neuronskih mreža. Na bazi rezultata eksperimentalnog ispitivanja obučene su veštačke neuronske mreže koje su sposobne da predvide amplitude brzine vibracija ležaja. Vibracije koje ležaj generiše zavise od niza uticajnih parametara koji se mogu podeliti na konstrukcione, tehnološke i eksploatacione. Modeli dobijeni primenom veštačkih neuronskih mreža određuju zavisnosti između uticajnih parametara i amplituda brzine vibracija koje ležaj generiše. Validacija neuronskih modela izvršena je na osnovu eksperimentalnih rezultata. Analiziran je uticaj svakog parametra ležaja na amplitude brzine vibracija u karakterističnim područjima frekvencija. U radu su prikazani i rezultati međusobnog uticaja više parametara. Modelima su dobijene preporučene vrednosti uticajnih parametara ležaja. Pri analizi tehnoloških parametara uvedeni su: parametar ekvivalentne površinske hrapavosti, parametar ekvivalentne valovitosti i parametar ekvivalentnog odstupanja od kružnosti staza kotrljanja. Novouvedeni parametri omogućavaju bolje razumevanje uticaja na dinamičko ponašanje. U radu je pokazano da su neuronski modeli sposobni da na osnovu parametara ležaja predvide klasu kvaliteta ležaja. The subject of this doctoral dissertation is the analysis of the dynamic behavior of ball bearings using artificial neural networks. Based on the results of the experimental test, artificial neural networks were trained to be able to predict the amplitudes of the bearing vibration velocity. The vibrations generated by the bearing depend on a number of influential parameters that can be divided into construction, technological and exploitation. Models obtained by applying artificial neural networks determined the dependences between the influencing parameters and the amplitudes of the vibration velocity generated by the bearing. Validation of neural models was performed based on experimental results. The influence of each parameter on the vibration velocity amplitudes in the characteristic frequency ranges was analyzed. The paper also presents the results of the mutual influence of several parameters. The models obtained the recommended values of the influential bearing parameters. In the analysis of technological parameters, the following parameters were introduced: the parameter of equivalent surface roughness, the parameter of equivalent waviness and the parameter of equivalent roundness error of raceways. The newly introduced parameters provide a better understanding of the impact on dynamic behavior. The paper shows that neural models are able to predict the bearing quality class based on bearing parameters.

Predmet istraživanja prikazanih u okviru doktorske diseracije su samopobudne vibracije pri obradi glodanjem. Na osnovu detaljne analize zakonitosti nastanka samopobudnih vibracija uspostavljena je određena paralela između glodanja i mikrogkodanja, za slučajeve kada je dubina rezanja veća od radijusa rezne ivice alata. Za tako usvojene pretpostavke, razvijeni su modeli unapređene numeričke simulacije procesa glodanja i mikroglodanja. Razvijeni modeli su svestrano verifikovani, s jedne strane, u segmentima gde postoje podaci u literaturi; poređenjem sa rezultatima drugih autora, a sa druge strane poređenjem sa sopstvenim eksperimentalnim ispitivanjima. Za eksperimentalno definisanje granične dubine rezanja pri glodanju predložena je inovativna metoda tangenti, a pri mikroglodanju, imajući u vidu raspoloživu mernu opremu, metoda hrapavosti obrađene površine. Matematički modeli i eksperimentalne metode su verifikovani pri obradi tri karakteristične vrste materijala i na dva obradna sistema pri glodanju, odnosno jednom materijalu i jednom obradnom sistemu pri mikroglodanju. Rezultati istraživanja su prezentovani kroz dvanaest poglavlja čiji sadržaj se navodi u nastavku. U prvom, uvodnom poglavlju, ukazano je na značaj istraživanja samopobudnih vibracija pri makro i mikroglodanju. Prikazana je i aktuelnost istraživanja analizom broja naučnih radova koji se bave problematikom samopobudnih vibracija u periodu od poslednjih dvadeset pet godina. Kroz drugo poglavlje detaljno su prikazana dosadašnja istraživanja samopobudnih vibracija pri makroglodanju, dok su u trećem poglavlju prikazana istraživanja samopobudnih vibracija pri mikroglodanju. Izvršena je analiza uticajnih parametri na graničnu dubinu rezanja, koja predstavlja osnovni pokazatelj dinamičke stabilnosti kako makro, tako i mikroobradnih sistema. Na osnovu saznanja prikazanih u okviru drugog i trećeg poglavlja u četvrtom poglavlju su definisani ciljevi i hipoteze istraživanja. Matematičke metode za definisanje karte stabilnosti obradnog sistema, prikazane su u petom poglavlju. Prikazana su dva matematička modela za definisanje karte stabilnosti pri makroglodanju, model srednjeg ugla kontakta alata u zahvatu i model Furijeovih redova. Prezentovana je numerička simulacija procesa obrade glodanjem, namenjena prvenstveno za simulaciju sila rezanja. Polazeći od prethodno prikazane ideje u okviru ovog poglavlja je razvijena nova matematička metoda predikcije granične dubine rezanja - unapređena numerička simulacija procesa glodanja. U okviru šestog poglavlja prikazane su eksperimentalne metode identifikacije vibracija mašina alatki, odnosno eksperimentalno određivanje modalnih parametara obradnih sistema kao i metode detekcije samopobudnih vibracija pri glodanju. U cilju definisanja granične dubine rezanja, prikazana je metoda frekventne analize vibracija pri glodanju, kao metoda koja se često koristi u savremenim eksperimentalnim istraživanjima. Međutim, i matematičke i eksperimentalne metode analize vibracija pri glodanju imaju određena ograničenja. Polazeći od prethodnog, razvijena je inovativna metoda tangenti, bazirana na ranije korišćenoj metodi u okviru Laboratorije za mašine alatke Instituta za proizvodno mašinstvo FTN u Novom Sadu, i primeni savremenih mernih sistema. Pored toga, u ovom poglavlju je eksperimentalno potvrđen uticaj samopobudnih vibracija na kvalitet obrađene površine i geometrijsku tačnost obratka. Metodologija sprezanja matematički i eksperimentalno definisanih funkcija frekventnog odziva elemenata mašine alatke prikazana je u sedmom poglavlju. Prezentovane su jednačine sprezanja pomerajnih odziva matematmički definisanih funkcija frekventnog odziva alata i držača alata, bazirane na Ojlerovoj teoriji grede, sa eksperimentalno definisanom funkcijom frekventnog odziva sklopa glavnog vretena mašine alatke. U okviru osmog poglavlja razvijen je matematički model sila rezanja pri mikroglodanju. Predloženi model sila rezanja, koji uzima u obzir silu trenja između leđne površine alata i obrađene površine, implementiran je u unapređenu numeričku simulaciju glodanja čime je omogućena njena primena za definisanje graničnih dubina rezanja pri mikroglodanju. Verifikacija razvijenih numeričkih i eksperimentalnih metoda za ispitivanje vibracija pri makroglodanju je prikazana u devetom poglavlju. Sproveden je niz eksperimentalnih ispitivanja, pri kojima su određivane granične dubine glodanja pri obradi tri različita materijala obratka (Al7075, 42CrMo4 i Ti-6Al-4V) na dva obradna sistema. Na osnovu ovih ispitivanjima izvršena je verifikacija unapređene numeričke simulacije glodanja i inovativne metode tangenti. U desetom poglavlju prikazana je verifikacija metoda analize samopobudnih vibracija pri mikroglodanju. Primenom metodologije sprezanja pomerajnih odziva, definisani su modalni parametri obradnog sistema za mikroobradu, potrebni za definisanje graničnih dubina rezanja, tj. karte stabilnosti, unapređenom numeričkom simulacijom mikroglodanja. Karta stabilnosti definisana razvijenom unapređenom numeričkom simulacijom, verifikovana je eksperimentalno i poređenjem sa literaturnim izvorima. U jedanaestom poglavlju data su zaključna razmatranja, kritički osvrt na ostvarene rezultate, i pravci budućih istraživanja. Dvanaesto poglavlje prikazuje pregled korišćene literature, koju čini 218 referenci većim delom citirane u samom radu, a u zasebnom poglavlju dati su prilozi. The subject of research presented in the doctoral dissertation are self-excited vibrations in milling. Based on a detailed analysis of the self-excited vibrations occurrence, a certain parallel has been established between macro and micromilling, for cases when the depth of cut is greater than the cutting edge radius of the tool. For such adopted assumptions, models of advanced numerical simulation of macro and micromilling processes were developed. The developed models were comprehensively verified, on the one hand, by comparison with the results of other authors, and on the other hand by comparison with own experimental results. An innovative tangent method has been proposed for the experimental definition of the cutting depth limit in milling, and the method of machined surface roughness has been proposed for micromilling, having in mind the available measuring equipment. Mathematical models and experimental methods were verified by machining three characteristic types of materials on two machining systems in macromilling, and one material on one machining system in micromilling. The results of the research are presented through twelve chapters, the content of which is listed below. In the first, introductory chapter, the importance of the research of self - excited vibrations in macro and micromilling is pointed out. The topicality of the research is also presented by analyzing the number of scientific papers dealing with the issue of self - excited vibrations in the period of the last twenty - five years. The second chapter presents in detail the previous research on self-excited vibrations during macromilling, while the third chapter presents research on self-excited vibrations during micromilling. An analysis of the influential parameters on the cutting depth limit was performed, which is a basic indicator of the dynamic stability of both macro and micromachining systems. Based on the findings presented in the second and third chapters, the fourth chapter defines the goals and hypotheses of the research. Mathematical methods for defining the stability lobe diagram of the machining system are presented in the fifth chapter. Two mathematical models for defining the stability lobe diagram for macromachining are presented, the model of the tool’s mean contact angle and the model of Fourier series. Numerical simulation of the milling process is presented, intended primarily for the simulation of cutting forces. Starting from the previously presented idea, a new mathematical method for predicting the cutting depth limit has been developed within this chapter - an improved numerical simulation of the milling process. In the sixth chapter, experimental methods of machine tools vibration identification are presented, ie experimental determination of machining systems modal parameters as well as methods of self - excited vibrations detection during milling. In order to define the cutting depth limit, the method of vibrations frequency analysis during milling is presented, as a method that is often used in modern experimental research. However, both mathematical and experimental methods of milling vibration analysis have certain limitations. Starting from the previous one, an innovative tangent method was developed, based on the previously developed method, used within the Laboratory for Machine Tools, Institute of Production Engineering Facultz of Technical Sciences in Novi Sad, and the application of modern measuring systems. In addition, in this chapter, the influence of self - excited vibrations on the machined surface quality and the geometric accuracy of the workpiece is experimentally confirmed. The methodology of machine tool elements mathematically and experimentally defined frequency response functions coupling is presented in the seventh chapter. The displacement responses coupling equations of mathematically defined tools and tool holders FRF's (based on Euler 's beam theory) with the experimentally defined FRF of the machine tool main spindle assembly are presented. Within the eighth chapter, a mathematical model of cutting forces in micromilling was developed. The proposed cutting forces model, which takes into account the friction force between the reliefe tool surface and the machined surface, is implemented in an advanced numerical micromilling simulation, which enables its application to define cutting depth limit in micromilling. Verification of the developed numerical and experimental methods for vibrations analysis during macromachining is presented in the ninth chapter. A series of experimental tests were performed, during which the cutting depth limits were determined during the milling of three different workpiece materials (Al7075, 42CrMo4 and Ti-6Al-4V) on two machining systems. In the tenth chapter, the verification of the methods of analysis of self-excited vibrations during micromilling is presented. Using the methodology of coupling displacement responses, the modal parameters of the machining system for micromachining are defined, needed to define the cutting depth limits, ie. stability lobe diagram, by advanced numerical micromilling simulation The stability lobe diagram, defined by the developed advanced numerical simulation, was verified experimentally and by comparison with literature sources. The eleventh chapter provides concluding remarks, a critical review of the achieved results, and directions for future research. The twelfth chapter presents an overview of the used literature, which consists of 218 references, mostly cited in the paper itself.

U prvom poglavlju je ukazano na potrebu ugradnje implantata u cilju ponovnog uspostavljanja normalnog funkcionisanja lokomotornog sistema čoveka. Na osnovu analize broja i strukture ugrađenih endoproteza zgloba kuka za 2014. i 2015. godinu na IOHB „Banjica“, Beograd, i Kliničkom centru Vojvodine Novi Sad, Klinika za ortopediju i traumatologiju, zaključuje se da ovi pokazatelji ukazuju na sličnost i uporedivost, sa podacima iz SAD, u odnosu na broj stanovnika. Drugo poglavlje, u uvodnom delu, sadrži sistematizaciju endoproteza zgloba kuka u skladu sa standardom ISO 7216. Nakon toga, dat je prikaz dosadašnjih rezultata primene tumorskih modularnih endoproteza. Pažnja je poklonjena opisu i varijantnosti konstrukcionih elemenata modularnih endoproteza zgloba kuka, kao i analizi izvedenih konstrukcionih rešenja. Prikaz dosadašnjih istraživanja je upotpunjen analizom patentnih rešenja modularnih endoproteza zgloba kuka. Na kraju, polazeći od prethodno sumiranih saznanja, i iskustva u razvoju protetičkih pomagala je definisan cilj istraživanja, osnovne hipoteze, materijal i metode. Treće poglavnje sadrži kratak prikaz koštanih tumora i istorijat tumorske endoproteze. Ukazuje se na komplikacije nakon ugradnje kao i na kriterijume za ugradnju tumorske endoproteze. Primarni i sekundarni tumori, neuspela aloartroplastika, prelomi preko ili ispod trohantera, patološki prelom, često prouzrukuju totalno razaranje gornjeg dela butne kosti, i ovi uslovi predstavljaju indikaciju za zamenu gornjeg dela butne kosti tumorskom endoprotezom. Cilj ugradnje tumorske endoproteze zgloba kuka je da se spase ekstremitet, očuva estetika i obezbedi zadovoljavajuća funkcionalnost i neutrališe prisustvo bola. Ne može se očekivati da endoprotetski sistem ima neograničen vek. Za pojedine delove koji su izloženi intenzivnom habanju u toku eksplatacije potrebno je obezbediti mogućnost jednostavne zamene uz minimalan hirurški zahvat. Sa biomehaničkog aspekta projektovanja, sistem fiksacije i konfiguracija tela endoproteze mora biti takav da minimizira naponsko stanje ili obezbedi povoljniju raspodelu napona. Četvrto poglavlje je posvećeno definisanju strukture i dimenzija komponenti sistema tumorske modularne endoproteze zgloba kuka. Ukazuje se na postupak i uticajne faktore na proces projektovanja, kao i na pouzdanost projektovanog rešenja. Posebna pažnja je posvećena dimenzionisanju donje komponente endoproteze sa stanovišta pojave koncentracije napona, kao i elementima za vezu i stezanje komponenti u jedinstven mehanički sistem. Dimenzije pojedinih komponenti su definisane na bazi statističkih razultata do sada ugrađenih tumorskih monolitnih endoproteza na IOHB „Banjica“ Beograd. U okviru petog poglavlja, prikazani su rezultati računarske analize statičkog ponašanja tela monolitne, odnosno donje komponente tumorske modularne endoproteze zgloba kuka. Prvo su prikazana preliminarna ipsitivanja pri statičkom opterećenju, i to računarsko simuliranje eksperimentalnih ispitivanja i sama eksperimentalna ispitivanja za obe vrste tumorskih endoproteza. Na bazi ovih rezultata izvršeno je remodelovanje donje komponente i umesto radijusa prelaza između kragne i tela - mesto maksimalnih napona u implantatu, definisan je optimalni bionički profil prelaza. Nakon izrade donjih komponenti od različitih materijala i različitih profila prelaza realizovana su završna ispitivanja komponenti tumorske modularne endoproteze pri statičkom opterećenju. I kod završnog ispitivanja prvo je izvršeno računarsko modelovanje a nakon toga i eksperimentalno ispitivanje. Pri eksperimentalnom ispitivanju meren je napon u jedanaest mernih tačaka po profilu prelaza između kragne i tela. Dobijeni rezultati su poređeni sa računarskim modeliranjem i konstatovano je zadovoljavajuće poklapanje raspodele i maksimalnih napona po profilu prelaza između kragne i tela endoproteze. Za slučaj delovanja dinamičkog opterećenja izvršena su eksperimentalna laboratorijska ispitivanja. Pri ovom ispitivanju definisane su sledeće promenljive: 1. vrsta endoproteze: monolitna i modularna, 2. materijal: superlegure čelika 316LVM i titanijuma Ti6Al4V, 3. oblik prelaza: sa radijusom i optimizirani prelaz. Cilj ovog ispitivanja ja da se utvrdi broj ciklusa koji će dovesti do početka razlabavljenja tela endoproteze pri maksimalnim uslovima opterećenja, tj. da li navedene promenljive daju statistički značajnu razliku u broju ciklusa do pojave razlabavljenja, kasne mehaničke komplikacije koja prethodi lomu usled zamora materijala, ili zahteva reviziju. Pri ovom ispitivanju fizički prototipovi endoproteza su, izloženi jednosmerno promenljivoj sili, Fmax=2500N, amplitude 2000N i frekvencije 15-20 Hz. Vršena je vizuelena kontrola pojave radiolucentne linije između tela endoproteze i koštanog cementa, odnosno kosti, kao pouzdani znak početka razlabavljenja, kao i Rtg snimaka od strane ortopedskih hirurga nakon svakih 500.000 ciklusa, za sve uzorke. Analiza rezultata nakon ispitivanja pri dinamičkom opterećenju uzoraka izrađenih od superlegure čelika 316LVM i uzoraka izrađenih od superlegure titanijuma Ti6Al4V ukazuje na visoku pouzdanost odnosno nizak nivo rizika da može doći do razlabavljenja i do pojave loma usled zamora materijala. Profil prelaza sa velikog na mali prečnik za slučaj radijusa i optimizirani bionički profil nisu pokazali značajnu statističku razliku kod ispitivanja pri dinamičkom opterećenju. Na kraju je pojava razlabavlja utvrđivana i inženjerskom metodom. Nakon ispitivanja dinamičkim opterećenjem fizički prototipovi endoproteza su ponovo izloženi statičkom opterećenju i konstatovano je da nema značajnijih promena u raspodeli i vrednostima maksimalnih napona, što ukazuje da nije došlo da pojave razlabavljenja. Kroz šesto poglavlje dat je kratak opis biokompatabilnih materijala, legura čelika 316LVM, kobalta CoCrMo, titanijuma Ti6A14V „eli“, poroznih i keramičkih materijala, materijala od plastične mase, kompozita i bioreseptivih materijala. Nakon toga su prikazani rezultati ispitivanja biokompatabilnosti materijala koji su primenjeni za izradu elemenata modularnog sistema endoproteza. Rezultati ispitivanja su pokazali da materijali i tehnološki proces proizvodnje zadovoljavaju sa stanovišta biokompatabilnosti. Sedmo poglavlje sadrži zaključke, na osnovu rezultata pojedinih poglavlja i izvedenih istraživanja. Nakon toga dati su pravci budućih istraživanja. Osmo poglavlje sadrži pregled korišćene literature, koju čini 68 literaturnih naslova od kojih je najveći broj citiran u radu. In the first chapter, the need of implant insertion was apostrophed, with the purpose to achieve normal functioning of human locomotory system. On the base of analysis of the number and the structure of implanted hip endoprosthesis during the years 2014. and 2015. at IOHB “Banjica”, Belgrade, and at Clinical center of Vojvodina, Novi Sad, Clinic of orthopedy and traumatology, it was concluded that the data, related to the number of citizens, show to be similar and comparable with those from the USA. In the second chapter, in the preface section, the systematization of hip endoprosthesis according to the norm ISO 7216 was presented. After that, the results of historical application of modular tumor endoprosthesis was presented. The attention was paid to the description and structure element variants of modular hip endoprosthesis, and also to the analyses of existing prosthesis constructions. The results of up to now conducted research were additionally enriched with patented variants of modular hip endoprosthesis. At the end, based on previously summed knowledge and experiences in the field of development of prosthetic aids, the goal of the research was determined, so as basic hypothesis, materials and methods. Third chapter comprises short description of bone tumors and historic development of tumor endoprosthesis. The complications after implantation were discussed and also the criteria for the implantation of tumor prosthesis. Primary and secondary tumors, failed arthroplasty, fractures across or beneath trochanter and pathologic fractures are frequent causes of total destruction of the upper portion of the femur and require the replacement of it with tumor prosthesis. The aim of hip tumor prosthesis implantation is to save the limb, to preserve esthetic, to provide satisfactory functionality and to neutralize the pain. It is not possible to expect that endoprosthetic system achieves en infinitely long service life. For some of the components, which are during the service exposed to intensive wear and tear, it is necessary to provide the possibility of simple replacement, with the need for a minimal surgical intervention. From the aspect of biomechanical design, the fixation system and body configuration of an endoprosthesis must be such, as to minimize stress level and to provide for a convenient stress distribution. The fourth chapter is dedicated to the definition of the structure and components’ dimensions for a system of modular hip endoprosthesis. It was dealt with the procedure and with the influencefull factors on a design process and also with the reliability of a designed solution. Special care was devoted to the dimensioning of the upper portion of endoprosthesis from the standpoint of stress concentration and to the elements for the connection and joining the elements in a compact mechanical system. The measures of certain components were defined on the base of statistic analysis of up to now implanted monolithic tumor endoprosthesis at IOHB “Banjica”, Belgrade. Within fifth chapter, the results of computer analysis of static behavior of the body of monolithic component (lower section) of modular tumor hip endoprosthesis was presented. As the first, the results of preliminary examinations with static load were presented, both the computer simulation of experimental testing and the results of real experimental testing, for both types of tumor endoprosthesis. On the base of these results, the remodeling of the lower component was undertaken so that instead of the connection of a collar and the prosthesis body with the shape of a constant radius (the spot with the maximum stress in the prosthesis), an optimal bionically shaped connection was defined. After the production of lower prosthesis components from different materials and with the different shapes, the final examinations of the components of modular tumor hip endoprosthesis under static load were performed. For the final examinations, in the first step also the computer modeling was performed, and consequently experimental testing. When performing experimental testing, the stress level was determined at eleven measuring spots, on the prosthesis section between the collar and the body. Acquired results were compared to the results acquired through computer modeling and an adequate overlapping of stress distribution and maximum stress in the region between the collar and the prosthesis body was detected. For the case of dynamic load, the laboratory experimental examinations were performed. For these examinations the following variables were determined: 1. endoprosthesis type: monolithic and modular, 2. material: steel superalloy 316LVM and of titanium Ti6Al4V, 3. shape of a connection between the collar and prosthesis body: with constant radius and with the optimized shape. The aim of this examination was to determine the number of cycles which would lead to the beginning of the loosening of the prosthesis body under the conditions of maximum load or, with other words, it was to be determined if mentioned variables provide for significant statistic difference in cycle numbers to the point of prosthesis loosening, to the consequent mechanic complication predicting material fatigue failure or demanding surgical revision. When conducting the examination, physical models of endoprosthesis were exposed to the influence of unidirectionally changing force with the parameters of Fmax = 2500N, Fampl = 2000N, frequency 15-20 Hz. After every 500.000 load cycles, for all the samples, the appearance of a radiolucent line between the prosthesis body and bone cement and the bone itself, as the reliable sign of the loosening onset, was visually checked on Rtg shots by orthopedic surgeons. The analysis of the results for behavior under dynamic load, for the samples from steel superalloy 316LVM and from titanium Ti6Al4V shows that they posses high reliability and that there is a low probability that the loosening and the fatigue failure will occur. When examined under dynamic load, prosthesis section with the change from small diameter to large diameter, for the case with constant radius and for the case with optimized bionic profile, have not shown statistically significant difference. At the end, the loosening appearance was examined under the application of engineering methods. After exposing the prosthesis to the dynamic load, physical prototypes of prosthesis were anew exposed to static load and it was confirmed that there is no significant change in the distribution and the level of maximum stress, what was the proof that no loosening has occurred. Within the sixth chapter, the short description of biocompatible materials was given, of steel alloy 316LVM, cobalt CoCrMo, titanium Ti6Al4V “eli”, of porous and ceramic materials, plastic materials, composites and bioreceptive materials. Subsequently, the results of biocompatibility examination of materials which were applied for the production of the elements of modular endoprosthesis system were presented. The acquired results have proved that the materials and the production process are satisfactory from the standpoint of biocompatibility. Seventh chapter comprises the conclusions, based on specific previous chapters and the research results. After that, the suggestions for the future research were outlined. Eight chapter comprises an overview of used literature, with 68 titles, most of which were cited in this work.