Jan Maciejewski, Ph.D., Dr. Habil., Eng.


Doctoral thesis
1996-11-28Analiza stanów pokrytycznych w procesach urabiania gruntów 
supervisor -- Prof. Zenon Mróz, Ph.D., Dr. Habil., Eng., IPPT PAN
525 
Habilitation thesis
2009-09-24Analiza procesów oddziaływania narzędzi maszyn roboczych na spoiste ośrodki gruntowe941
 
Recent publications
1.Kowalewski Z.L., Szymczak T., Maciejewski J., Material effects during monotonic-cyclic loading, INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES, ISSN: 0020-7683, DOI: 10.1016/j.ijsolstr.2013.10.040, Vol.51, pp.740-753, 2014
Abstract:

The effects commonly related with deformation caused by proportional and non-proportional loading types were identified experimentally. In the case of non-proportional cyclic loading along circular strain path the second order effects such as: phase shift between stress and strain signals was observed. An analysis of experimental data from tests under non-proportional cyclic loading along square strain path exhibited a significant reduction of stress independently on direction of deformation.

The paper also presents experimental results concerning evaluation of an influence of cyclic loading on stress variations during monotonic deformation carried out on the pure copper and X10CrMoVNb9-1 steel. All strain controlled tests were performed at room temperature using thin-walled tubular specimens. The experimental programme contained selected combinations of monotonic and cyclic loadings, i.e. the torsion-reverse-torsion cycles were superimposed on the monotonic tension. It is shown that such cycles associated with monotonic tension caused essential variations of tensile stress. For both materials, a significant decrease of the axial stress was visible. The effects observed during monotonic and cyclic loading combinations were theoretically described using the Mróz and Maciejewski model.

Keywords:

Proportional and non-proportional loadings, Hardening, Softening, Tensile stress, Strain energy, Yield surface, Modelling

Affiliations:
Kowalewski Z.L.-IPPT PAN
Szymczak T.-Bialystok University of Technology (PL)
Maciejewski J.-other affiliation
2.Maciejewski J., Mróz Z., An upper-bound analysis of axisymmetric extrusion assisted by cyclic torsion, JOURNAL OF MATERIALS PROCESSING TECHNOLOGY, ISSN: 0924-0136, DOI: 10.1016/j.jmatprotec.2007.12.061, Vol.206, pp.333-344, 2008
Abstract:

Technological metal forming processes of extrusion, forging and rolling with imposed cyclic torsion or shear deformation are of engineering interest in view of their advantages with respect to monotonic loading processes. The present work is aimed at the analysis of an axisymmetric extrusion process assisted by cyclic torsion, which can be induced by a cyclically rotating die with a specified rotation amplitude and frequency. The material is assumed to be rigid-perfectly plastic and the upper-bound analysis for a kinematically admissible flow field is presented. The field parameters are specified from the condition of minimum plastic dissipation. The evolution of the extrusion force and torsional moment is studied and the corresponding plastic flow field is specified, with process control parameters such as the ratio of extrusion and rotation rates, and the amplitude of die rotation. For increasing rotation frequency, it is shown that localization of plastic flow occurs in the bottom zone close to the rotating die. The analysis allows for specification of process control parameters and their relation to extrusion force, torsional moment, and the associated plastic dissipation for varying reduction ratios.

Keywords:

Extrusion, Cyclic torsion, KOBO method, Upper-bound analysis, Process control parameters

Affiliations:
Maciejewski J.-IPPT PAN
Mróz Z.-IPPT PAN
3.Maciejewski J., Mróz Z., Analiza procesu wyciskania metali wspieranego deformacją cykliczną, RUDY I METALE NIEŻELAZNE, ISSN: 0035-9696, Vol.11, pp.668-677, 2007
Abstract:

Przedstawiono analizę procesu osiowosymetrycznego wyciskania metali przy nałożeniu cyklicznego skręcania wywoływa-nego matrycą ( metoda KOBO, [1÷4]). Założono uproszczony model sztywno-plastycznego materiału bez wzmocnienia i ki-nematycznie dopuszczalny mechanizm płynięcia. Z warunku równości mocy dyssypacji plastycznej i mocy sił zewnętrznych (siła osiowa i moment skręcający) określono wartość [...]

Affiliations:
Maciejewski J.-IPPT PAN
Mróz Z.-IPPT PAN
4.Maciejewski J., Kopeć H., Petryk H., Finite element analysis of strain non-uniformity in two processes of severe plastic deformation, ENGINEERING TRANSACTIONS (ROZPRAWY INŻYNIERSKIE), ISSN: 0867-888X, Vol.55, No.3, pp.197-216, 2007
Abstract:

Two severe plastic deformation (SPD) processing techniques, namely equal-channel angular pressing (ECAP) and cyclic extrusion-compression (CEC), are investigated by using the finite element method. The major aspect examined is the non-uniformity of the accumulated, equivalent plastic strain after processing with the use of different shapes of the die. The quantitative effect of several parameters on the plastic flow is determined. It is found that the diameter ratio of the chambers and narrower channel in the CEC method, and also the inclination angle of connecting conical parts, can affect strongly the degree of strain non-uniformity. Comparison is made of distributions of equivalent strain after two passes of ECAP for two different routes and with two die profiles.

Affiliations:
Maciejewski J.-IPPT PAN
Kopeć H.-other affiliation
Petryk H.-IPPT PAN
5.Mróz Z., Kowalczyk-Gajewska K., Maciejewski J., Pęcherski R.B., Tensile or compressive plastic deformation of cylinders assisted by cyclic torsion, ARCHIVES OF MECHANICS, ISSN: 0373-2029, Vol.58, No.6, pp.497-527, 2006
Abstract:

Technological metal forming processes of extrusion, forging and rolling with imposed cyclic torsion or shear deformation have been recently studied in view of their advantages with respect to monotonic loading processes, cf. Bochniak and Korbel [2–4]. The present work is aimed to analyze such process in the case of simple tension or compression of a cylindrical tube with imposed cyclic torsional deformation. The material element response is assumed to be rigid-perfectly plastic or elastic-perfectly plastic. For these models, the analytical solutions can be provided for the steady cyclic responses and the effect of two process parameters, namely the ratio of shear and axial strain rates η and the amplitude of shear strain γm , can be clearly demonstrated. Three different regimes of cyclic response can be visualized in the plane η, γm. The cyclic response of a cylinder under combined axial compression and cyclic torsion is predicted by considering a simplified model of a set of concentric tubes and neglecting their radial stress interaction. The axial force and torsional moment are then specified by averaging the responses of consecutive tubes. The cyclic response diagrams for the cylinder are then generated in terms of axial force and torsional moment related to axial deformation and angle of twist

Keywords:

cyclic torsion, plastic deformation of cylinders, elastic-perfectly plastic model, rigid-perfectly plastic model, analytical solutions of cyclic response of a cylinder

Affiliations:
Mróz Z.-IPPT PAN
Kowalczyk-Gajewska K.-IPPT PAN
Maciejewski J.-IPPT PAN
Pęcherski R.B.-IPPT PAN
6.Maciejewski J., Trąmpczyński W., Sokołowski K., Modelowanie procesu urabiania ośrodka spoistego łyżką koparki z uwzględnieniem zużycia zębów, Czasopismo Techniczne. Mechanika, ISSN: 0011-4561, Vol.1, pp.275-284, 2005
7.Mróz Z., Maciejewski J., Failure criteria of anisotropically damaged materials based on the critical plane concept, INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, ISSN: 0363-9061, DOI: 10.1002/nag.207, Vol.26, No.4, pp.407-431, 2002
Abstract:

The damage state of a cracked material is assumed to be specified by crack density distribution on physical planes. The critical plane approach is used with account for damaged and intact area fractions on the plane. The maximum of failure function is specified for all potential failure planes and the critical plane orientation is determined. The resulting failure condition is applied to study strength evolution for triaxially compressed specimens with varying orientation of principal stress and damage tensor axes. Both Coulomb and non-linear failure conditions of Mohr type are applied to specify the representative critical plane. A general stress state is considered and the failure condition is specified for different relative orientations of orthotropy and principal stress axes.

Affiliations:
Mróz Z.-IPPT PAN
Maciejewski J.-IPPT PAN

List of recent monographs
1.
84
Maciejewski J., Analiza procesów oddziaływania narzędzi maszyn roboczych na spoiste ośrodki gruntowe, IPPT Reports on Fundamental Technological Research, 1, pp.1-262, 2008
List of chapters in recent monographs
1.
397
Kowalewski Z.L., Szymczak T., Maciejewski J., Inelastic Behavior of Materials and Structures Under Monotonic and Cyclic Loading, rozdział: Experimental and Numerical Investigations of the Effects Associated to Complex Loading Combinations, Springer, Altenbach H., Brunig M. (Eds.), pp.117-142, 2015
2.
279
Maciejewski J., Białas M., Mróz Z., 6th European Congress on Computational Methods in Applied Sc. and Engng. (ECCOMAS 2012), September 10-14, 2012, Vienna, Austria, rozdział: Modelling of contact interface oxidation process at asperity scale, University of Vienna, Austria, pp.1-8, 2012
3.
40
Mróz Z., Maciejewski J., Bifurcations, Instabilities and Degradations in Geomaterials, rozdział: Critical Plane Approach to Analysis of Failure Criteria for Anisotropic Geomaterials, Springer-Verlag Berlin Heidelberg, pp.69-89, 2011
4.
41
Maciejewski J., Mróz Z., Bifurcations, Instabilities and Degradations in Geomaterials, rozdział: Analysis of Deformation and Damage Processes in Soil-Tool Interaction Problems, Springer-Verlag Berlin Heidelberg, pp.325-345, 2011

Conference papers
1.Kowalewski Z.L., Szymczak T., Maciejewski J., Effects observed under monotonic-cyclic loading combinations: experiment and modelling, PACAM, 14th Pan-American Congress of Applied Mechanics, 2014-03-24/03-28, Santiago (CL), pp.1-6, 2014
Abstract:

The effects often taking place during proportional and non-proportional types of loading were identified experimentally and modelled numerically. In the case of non-proportional cyclic loading along circular strain path the second order effects such as: phase shift between stress and strain signals were discovered. An analysis of experimental data from tests under non-proportional cyclic loading along square strain path exhibited a significant reduction of stress independently on direction of deformation. The paper also presents experimental results concerning evaluation of an influence of cyclic loading on mechanical parameters during monotonic deformation carried out on the 2024 aluminium alloy and X10CrMoVNb9-1 steel. All strain-controlled tests were conducted at room temperature using thin-walled tubular specimens. The experimental programme contained selected combinations of monotonic and cyclic loadings, i.e. the torsion-reverse-torsion cycles were superimposed on the monotonic tension. It is shown that such cycles caused essential variations of the tension characteristics. A significant decrease of the tension stress was observed. The effects occured during monotonic and cyclic loading combinations were described using Mróz and Maciejewski model. Reasonable good predictions of: hysteresis loops and stress responses for the square and circular loading paths and tensile curves assisted by torsion cycles were obtained

Keywords:

cyclic loading, hardening, softening, complex stress state

Affiliations:
Kowalewski Z.L.-IPPT PAN
Szymczak T.-Bialystok University of Technology (PL)
Maciejewski J.-other affiliation

Conference abstracts
1.Kowalewski Z.L., Szymczak T., Maciejewski J., Material effects during monotonic-cyclic loading conditions, Plasticity 2014, 20th International Symposium on Plasticity and its Current Applications, 2014-01-03/01-08, Freeport (BS), pp.100-102, 2014
Abstract:

The effects commonly taking place during proportional and non - proportional (circle and square) types of loading were identified experimentally. Experimental results of tests under cyclic loading assisted by monotonic deformation are compared to their predictions using the Mróz - Maciejewski model

Affiliations:
Kowalewski Z.L.-IPPT PAN
Szymczak T.-Bialystok University of Technology (PL)
Maciejewski J.-other affiliation
2.Maciejewski J., Białas M., Mróz Z., Two scale modelling of wear and oxidation processes, FRICTION 2012, VII International Conference, Modelling And Simulation Of The Friction Phenomena In The Physical And Technical Systems, 2012-05-22/05-22, Warszawa (PL), 2012
3.Maciejewski J., Białas M., Mróz Z., Evolution of friction coefficient in the tribological test, XX FRENCH-POLISH SEMINAR OF MECHANICS, 2012-05-12/05-12, Warszawa (PL), 2012
4.Maciejewski J., Mróz Z., Deformation response of geomaterial interfaces coupled with progressive damage and wear, SolMech 2010, 37th Solid Mechanics Conference, 2010-09-06/09-10, Warszawa (PL), pp.248, 2010
5.Kowalewski Z.L., Szymczak T., Maciejewski J., On the mutual interactions of monotonic and cyclic loading – experiments and theoretical predictions, Workshop on Constitutive Modeling in Applications for Industrial Processes, 2010-09-01/09-03, Kraków (PL), pp.1-2, 2010