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1
Content available remote The effect of severe plastic deformation on the IF steel properties, evolution of structure and crystallographic texture after dual rolls equal channel extrusion deformation
Jabłońska M. B., Kowalczyk K., Tkocz M., Chulist R., Rodak K., Bednarczyk I., Cichański A.
Archives of Civil and Mechanical Engineering
|
2021
|
Vol. 21, no. 4
310--319
EN
This paper presents some results of the influence of severe plastic deformation on the microstructure evolution, grain refinement aspect, and mechanical properties of ultra-low carbon steel. Ti-stabilized experimental IF steel was deformed at a room temperature with unconventional SPD process—dual rolls equal channel extrusion (DRECE). Mechanical properties and structure of ferritic steel in initial state and after selected steps of deformation were investigated. The mechanical properties were determined by static tensile tests carried out at a room temperature and microhardness research. The structural investigations involved using scanning transmission electron microscopy observations, electron back scattered diffraction and measurements of the crystallographic texture. The DRECE process affects the evolution of the structure. The microstructural investigations revealed that the processed strips exhibited a dislocation cell and grain structures with mostly low angle grain boundaries. The electron backscattering diffraction (EBSD) examination showed that the processed microstructure is homogeneous along the strips thickness. The mechanical properties of the DRECE-processed IF steel strips increased with an increase the number of passes.
2
Content available Determining effective length for 40 HM-T steel by use of non-local line method concept
Robak G., Krzyżak D., Cichański A.
Polish Maritime Research
|
2018
|
nr 1
128--136
EN
In the paper, the concept of non-local line method is presented and used for determining the effective length for notched elements. Experimental tests and calculations were performed for 40 HM-T (42CrMo4+QT) steel made specimens of two types, i.e. smooth specimens, and notched specimens with notch radius equal to 0.2 mm, 0.5 mm, 0.8 mm, and 1 mm. The performed FEM calculations took into account the multi-linear hardening model and cyclic material properties. The concept of the presented non-local line method bases on finding the position of critical plane and determining the effective length, meant as the fracture process zone. During numerical stress gradient simulations, also the weight function was implemented. It was observed that the effective length increases as the load increases.
3
Modelowanie uderzenia lekkiego samochodu w element wsporczy infrastruktury drogowej
Cichański A., Skibicki D., Stopel M.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2014
|
z. 103
47--48
EN
The paper presents a numerical analysis of the impact of the light car in the road infrastructure performed. Analysis conducted in the LS-Dyna environment made it possible to verify the selection of the design features of the foot of the mast. Accepted structure should meet the requirements for the Non-Energy categories according to PN-EN 12767.
PL
Wraz z rozwojem środków transportu kołowego rosną wymagania stawiane przed infrastrukturą drogową w zakresie wytrzymałości, trwałości, ale również bezpieczeństwa .Jako bezpieczniejsze przyjmuje się rozwiązania, w których konstrukcje wsporcze nie pochłaniają energii, a ulegają rozdzieleniu lub odkształceniu podczas gdy pojazd kontynuuje ruch ze zmniejszoną prędkością. Ryzyko wystąpienia obrażeń pierwotnych u pasażerów podczas uderzenia w taką konstrukcję jest niższe w porównaniu do konstrukcji pochłaniających energię. Wymagania dotyczące zachowania pojazdów podczas uderzenia w nieruchome konstrukcje wsporcze dla urządzeń drogowych zostały opisane w normie PN-EN 12767. Norma ta określa poziomy bezpieczeństwa biernego, uwzględniając ruch pojazdów i pasażerów po zdarzeniu drogowym [1]. Najwyższy stopień ograniczenia skutków uderzenia zapewniają konstrukcje nie pochłaniające energii NE. Poprawność doboru cech konstrukcyjnych infrastruktury drogowej jeszcze na etapie konstruowania jest weryfikowana analizami komputerowymi. Do modelowania uderzeń w elementy infrastruktury drogowej powszechnie wykorzystywane jest środowisko LS-Dyna [2, 3]. W pracy podjęto problematykę modelowania uderzenia lekkiego pojazdu w maszt konstrukcji wsporczej dla planszy informacyjnej.
4
Content available Tensometric verification of numerical calculations of frame structure of single axis manure spreader
Cichański A., Skibicki D., Lis Z., Burak M., Stopel M.
Journal of Polish CIMAC
|
2013
|
Vol. 8, no 3
15--23
EN
The study presents a manner of experimental testing of frame structure of single axis manure spreader. The work aimed at verification of strains determined by FEM in two areas. The first area was the manure box floor, which operated in harshest conditions. The other issue involved verification of correctness of maximum strains determined for the entire structure. Significant issue was to consider of variability of distribution and values of loads. The work suggests reflecting of the variable values through a set of manure box load variants describing stages of the manure spreader loading, unevenness of loading as well as unloading. Obtained by experiment values of stresses have been compared with results of numerical calculations by finite elements method which has proven their high compliance. Maximum stresses have been determined with accuracy of ca. 7%. A load variant affects determined strain values. Strains determined in variants reflecting loading and unevenness of load are characterised by a smaller error than in the case of variants reflecting unloading. This indicates to a greater accuracy of determination of strains with higher values.
5
Content available Numerical analysis of frame structure of single axis manure spreader
Cichański A., Burak M., Stopel M.
Journal of Polish CIMAC
|
2013
|
Vol. 8, no 3
9--14
EN
The study describes issues of research of frame structure of single axis manure spreader of loading capacity 14t. During the tests state of stress in frame structure and manure box have been specified. Manner of preparation of numerical model and results of tests performed with its use have also been described. On the basis of the results modification of the construction in critical areas has been proposed. Introduction of modifications resulted in improvement of frame structure of manure spreader strength state.
6
Content available Strain gauge verification of numerical analysis of forage trailer supporting structure
Cichański A., Burak M., Skibicki D., Lis Z.
Journal of Polish CIMAC
|
2012
|
Vol. 7, no 3
41-46
EN
The paper presents experimental verification of forage trailer supporting structure. Conditions for performance of strain gauge measurements of stresses at selected frame points were presented. Results of strain gage measurements were compared with results of calculations by method of complete elements. Dozen percentage compliance of results of numerical calculations and experimental measurements was obtained. Maximum stresses were specified with accuracy of ca.2%. During measurements asymmetrical distribution of load in the frame was stated.
7
Content available Numerical analysis of forage trailer supporting structure
Cichański A., Burak M., Skibicki D., Stopel M.
Journal of Polish CIMAC
|
2012
|
Vol. 7, no 3
29-34
EN
The paper discusses issues of examination supporting structure of forage trailer. Tests were applied to supporting structure, lowered in order to adjust the height of mix feeding for younger cattle. Lowering obtained by spreading of supports caused increase of the structure effort and increase of stress exceeding acceptable values. The paper describes the manner of preparation of numerical model and results of tests performed with its application. Based upon the results modification of the structure in critical areas was proposed. Implementation of such modifications resulted in improvement of effort of forage trailer supporting structure.
8
Content available Analytical verification of numerical analysis of forage trailer supporting structure
Cichański A., Burak M., Skibicki D., Pejkowski Ł.
Journal of Polish CIMAC
|
2012
|
Vol. 7, no 3
35-40
EN
The paper presents manner of analytical modelling of forage trailer supporting structure. Process of obtaining mathematical model from physical model was presented as well as final form of mathematical model in the form of equations describing deflections and stresses of the forage trailer construction. Results of analytical calculations were compared with results of numerical calculations with the method of complete elements. Good, 5%, compliance of the results of analytical and numerical calculations was achieved.
9
Content available Applicability of Indicators of Trabecular Bone Structure for Evaluation of its Mechanical Properties
Cichański A., Nowicki K., Mazurkiewicz A., Topoliński T.
Acta Mechanica et Automatica
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2012
|
Vol. 6, no. 3
27-30
EN
The paper presents the results of examination of relations between indicators describing trabecular bone structure and its static and cyclic compressive strength. Samples of human trabecular bone were subject to microtomographic tests in order to specify indicators describing its structure. Part of the samples was subject to static compression tests, part to cyclic compressing loads with stepwise increasing amplitude. Evaluation of a degree of applicability level of estimation of bone compressive strength properties was conducted based upon values of structure indicators. Evaluation was performed based upon values of obtained determination coefficients R2 for linear regression. Obtained R2 values were within the range of 0.30-0.51 for relations between examined indicators and static compressive strength within the range of 0.47-0.69 for relations with the results of cyclic test with stepwise increasing amplitude.
10
Content available Relationship between fatigue life and structural indices of human trabecular bone
Topoliński T., Mazurkiewicz A., Cichański A., Nowicki K.
Journal of Polish CIMAC
|
2010
|
Vol. 5, no 3
101-106
EN
Trabecular bone is one of components of human bone. It is a porous structure which strength has principal influence on strength whole bone. In the study has been presented results investigation relationship between fatigue life (loading with stepwise increasing amplitude) and structural indices of human trabecular bone. Dependencies were described by determination coefficient R2. Obtained values the coefficient were contained in range 0,50÷0,69.
11
Content available Numerical verification of quasi-static strength of the horizontal bicycle welded frame
Cichański A., Tomaszewski T.
Journal of Polish CIMAC
|
2010
|
Vol. 5, no 3
13-17
EN
Horizontal bicycles can be classified as means of transport powered by one's own muscles that are in the lead as regards low aerodynamic drag, riding comfort and safety. This kind of construction is influenced by load that in the case of inadequately engineered bicycle frame may lead to the construction damage. To prevent this, strength and stiffness analyses are conducted whose boundary conditions correspond with these during real exploitation. Various extrusion profiles of the bicycle frame are connected with the use of welding technique which additionally makes us conduct analysis strength of welded joints. These kinds of calculations are carried out with the use of the software basing on the finite element method making it possible to gain stress and deformation values for complex cases of frame load and whose results cannot be obtained in an analytical way. The frame of the horizontal bicycle was put to analysis in the three different load variants. We achieved maximum deformation, stress in the critical points and in the welding joints of the frame, which then were compared to the allowable values. The correct verification of the received values contributed to determining joints vulnerable to damaging and modifying the frame construction to minimalize the possibility of its destruction.
12
Content available Influence of MESH morphology near the notch on precision of SCF determination
Cichański A.
Journal of Polish CIMAC
|
2010
|
Vol. 5, no 2
55-63
EN
The researches considered the problem of mesh forming for numerical analyses of notched elements. Stress concentration factor Kt was assumed as the characteristic value determined during the calculations. The calculations were performed for flat bars with opposite U-shaped notches and for round bars with V-shaped notches. Both analysed the notchs generally assumed as shallow notch Kt.1.7 and sharp notch Kt.2.8. Two-dimensional FEM linear elastic analyses were performed in the ANSYS software environment. For the purpose of the analyses, free and mapped meshes for coarse geometry and mapped meshes for modified geometry with one and two subareas were assumed. It has been revealed that precision of numerical calculations for stress concentration factor depends on morpholology of the mesh located near the notch. It has been revealed that free mesh enables to obtain a satisfying precision of the calculations. Introduction of division in formed geometry of the notch for sub-areas followed by their division according to the standard did not improve precision.
13
Content available Egronomic analysis of anthropo-technical systems in the environment of catia-program
Cichański A., Wirwicki M.
Journal of Polish CIMAC
|
2010
|
Vol. 5, no 3
19-25
EN
Every engineer designer when designing the interior of a passenger car must obey certain norms and regulations. When engineer designer introduces innovative solutions of different equipment in the passenger car interior, he must create comfortable conditions for a driver. The article describes the applied issues concerning the interior ergonomics of a passenger car. A designer using CATIA type programs can put the designed model of car interior to work ergonomics analysis for basic service activities of a car driver. A male and female dummies from the European population were created for the purpose of conducting the analysis. The interior of a passenger car was designed and its most important elements were described. The engineer designer having general dimensions of the interior starts analysis which will be a base for the change in cabin dimensions. In this analysis two main positions of a driver were assumed: a sitting position with hands on steering wheel and a sitting position with a right hand holding gear shift stick. It was shown in which areas of the cabin of the passenger car changes in dimensions are necessary and then driver's comfort improvement was shown in percentage.
14
Content available remote Investigation of statistical relationships between quantities describing bone architecture, its fractal dimensions and mechanical properties
Cichański A., Nowicki K., Mazurkiewicz A., Topoliński T.
Acta of Bioengineering and Biomechanics
|
2010
|
Vol. 12, no. 4
69-77
EN
The paper presents linear, logarithmic and exponential regression tabecular bone indices, fractal dimensions and strength. The analysis of the above parameters was supported by determining non-parametric correlation coefficients: Spearman’s ń, gamma and Kendall’s ô. The principal components’ analysis (PCA) was also performed in order to reduce the number of indices describing the variance in the data set. The analysis showed the most independent indices: lacunarity (ëm, ëmin, ëmax), BMD, Conn.D., SMI, DA, ńA and age.
15
Content available Uśrednianie odkształceń w płaszczyźnie krytycznej materiału w ocenie trwałości zmęczeniowej elementów z karbem
Karolczuk A., Cichański A.
Acta Mechanica et Automatica
|
2010
|
Vol. 4, no. 2
86-92
PL
W pracy przeanalizowano wpływ wielkości pola powierzchni uśredniania odkształcenia normalnego w płaszczyźnie krytycznej na ocenę trwałości zmęczeniowej próbek z karbem obrączkowym o dwóch promieniach zaokrąglenia dna karbu. W weryfikacji wykorzystano wyniki badań eksperymentalnych, zaczerpniętych z literatury, przeprowadzonych na ma- teriale AISI 1141 w dwóch stanach bez i po obróbce cieplnej. Obróbka cieplna zmieniła charakterystyki cykliczne materiału. Zmiana charakterystyki cyklicznej krzywej odkształcenia wyraźnie wpłynęła na wielkość obszaru uśredniania.
EN
The paper analyses the influence of the size of the area in averaging process of strains over critical plane on the calculated fatigue life. The averaged strain is used as nonlocal parameter in fatigue life calculation. The analysis is performed on experimental results obtained on specimens with different notch radius. Specimens were made of a vanadium-based microalloyed forging steel AISI 1141, in both as-forged (AF) and quenched and tempered (QT) conditions. Heat treatment has changed cyclic properties of the material. The change in the cyclic stress-strain curve by heat treatment has influenced the size of the averaging area.
16
Content available Experimental method of defining biaxial fatigue properties of elastic-plastic construction materials. Part 2 - Experimental research
Cichański A., Sempruch J.
Journal of Theoretical and Applied Mechanics
|
2005
|
Vol. 43 nr 1
65--80
EN
The paper is concerned with the authors' own method of defining biaxial fatigue properties of elastic-plastic construction materials, for which a theoretical basis was formulated before (Cichański and Sempruch, 2005). In the present paper, results of experimental investigations (divided into preliminary and main research) appropriate for the proposed method are described. In the preliminary research phase, an experimental verification of major assumptions and numerical verification of conditions on preparation of test specimens were carried out. During the main research phase, model parameters of plastic and fatigue properties were described and the evaluation of the proposed model (Cichański and Sempruch, 2005) was done.
PL
Niniejsza praca jest zorientowana na własną metodę wyznaczania dwuosiowych własności zmęczeniowych sprężysto-plastycznych materiałów konstrukcyjnych, dla której podstawy teoretyczne zostały sformułowane wcześniej (Cichański i Sempruch, 2005). W prezentowanej pracy przedstawiono wyniki badań doświadczalnych właściwych dla zaprezentowanej metody, podzielonych na badania wstępne i główne. Na etapie badań wstępnych wykonano doświadczalną weryfikację najważniejszych założeń metody oraz numeryczną weryfikację warunków przygotowania próbek do badań. Na etapie badań zasadniczych wyznaczono modelowe parametry opisu własności plastycznych i zmęczeniowych oraz dokonano oceny modelu zaproponowanego w Cichański i Sempruch (2005).
17
Content available Experimental method of defining biaxial fatigue properties of elastic-plastic construction materials. Part 1 - model formulation
Cichański A., Sempruch J.
Journal of Theoretical and Applied Mechanics
|
2005
|
Vol. 43 nr 1
51--64
EN
The paper presents formulation of a method of biaxial fatigue testing in conditions of cyclic uniaxial loads with the use of specimens made of a material characterised by controlled mechanical properties. The origin for the paper was a successful attempt to adapt the plastic potential for describing biaxial fatigue strength made by Troost and El.-Magd (1974) in relation to the "stress anisotropy" effect, pointed out by him. On the basis of the carried-out reasoning, a model formulation of the allowable stress amplitude was introduced, which is a formalised record of the relations between the fatigue stress amplitudes and the yield stresses. The article suggests an experimental method of defining the appointed model parameters, which is a development of Szczepiński's method (Szczepiński, 1963).
PL
W artykule przedstawiono sformułowanie metody badania dwuosiowego zmęczenia w warunkach cyklicznych obciążeń jednoosiowych z wykorzystaniem próbek wykonanych z materiału o kontrolowanych własnościach mechanicznych. Jako genezę pracy wskazano udaną próbę adaptacji potencjału plastycznego do opisu dwuosiowego zmęczenia wykonaną przez Troosta (Troost i El.-Magd, 1974) w odniesieniu do wskazanego przez niego efektu "anizotropii naprężeniowej". Na podstawie przeprowadzonego rozumowania wyprowadzono modelowe ujęcie dopuszczalnej amplitudy naprężeń będące sformalizowanym zapisem zależności amplitudy naprężeń zmęczeniowych od naprężeń uplastyczniających. W pracy zaproponowano doświadczalną metodę wyznaczania parametrów wskazanego modelu, będącą rozwinięciem metody Sczepińskiego (Szczepiński, 1963).
18
Przegląd doświadczalnych metod badania dwuosiowego zmęczenia
Cichański A., Świtała A.
Zeszyty Naukowe. Mechanika / Akademia Techniczno-Rolnicza w Bydgoszczy
|
2002
|
Z. 52(240)
5-15
PL
W pracy przedstawiono przegląd doświadczalnych metod badania dwuosiowego zmęczenia pod kątem kształtowania próbki. Wskazano grupę metod uznawanych za standardowe, natomiast szerzej omówiono niestandardowe metody badania dwuosiowego zmęczenia.
EN
The paper presents a review of experimental methods of biaxial fatigue testing. The review has been made from the point of view of specimen shaping. A group of methods considered standard has been given. The group includes the methods using solid speci-mens, thin-walled tubes and cruciform specimens. Also non-standard methods of biaxial fatigue testing have been widely described. The group includes methods which draw on thick-walled tubes, elliptical and rhombic plates, specimens in the shape of revolving disc and the specimens whose shape was developed by the author's.
19
Opracowanie konstrukcji i badania prototypu nożycowego podnośnika rampowego
Cichański A., Skibicki D., Sempruch J.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2001
|
z. 68
187-194
PL
W pracy przedstawiono etapy procesu opracowywania konstrukcji oraz wyniki badania prototypu nożycowego urządzenia podnośnikowego typu rampa samochodowa. Prezentowane zagadnienie opracowano w ramach projektu celowego realizowanego przez wybrane Katedry ATR w Bydgoszczy we współpracy z przedsiębiorstwem "Techma-Bydgoszcz" S.A.
EN
In the paper the stages of constructions process of the scissors lift table was presented. Also the main technology problems was described. Chosen test of the prototype and some results was shown.
20
Dydaktyka komputerowego wspomagania projektowania jako otoczenie grupy przedmiotowej PKM
Cichański A., Sempruch J., Skibicki D.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2001
|
z. 68
181-185
PL
W artykule przedstawiono syntetycznie dydaktykę z zakresu CAD prowadzoną na Wydziale Mechanicznym ATR w Bydgoszczy. Dydaktykę CAD przedstawiono jako otoczenie dla grupy przedmiotowej PKM. W tym ujęciu, przedmioty CAD omówiono, dzieląc je na trzy zakresy merytoryczne: podstawy informatyki, zapis konstrukcji oraz obliczeniową weryfikację konstrukcji.
EN
A CAD didactic lead in Mechanical Engineering Faculty of University of Technology in Bydgoszcz was synthetically presented in the paper. CAD didactic was presented as a surrounding of basic of machines didactic. CAD subjects were divided in three groups in respect of essential range: basics of informatics, design recording and computational verification of design.
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