Prof. Lech Dietrich, Ph.D., Dr. Habil., Eng.

Department of Experimental Mechanics (ZMD)
Division of Applied Thermomechanics (PTS)
retiree
telephone: (+48) 22 826 98 00
telephone: (+48) 22 826 12 81 ext.: 262
room: 035
e-mail: ldietr

Doctoral thesis
1969Teoretyczna i doświadczalna analiza nośności granicznej w zagadnieniach kontaktowych 
supervisor -- Prof. Wojciech Szczepiński, Ph.D., Dr. Habil., Eng., IPPT PAN
166 
Habilitation thesis
1978Uwzględnienie wzmocnienia materiału w analizie złożonych procesów plastycznego płynięcia 
Professor
1990Title of professor
Supervision of doctoral theses
1.2009-09-24Widłaszewski Jacek Modelowanie i badania doświadczalne termo-plastycznych deformacji aktuatora dwumostkowego633
 
2.2009-06-18Garbacz Grzegorz  Przetwarzanie danych doświadczalnych z uwzględnieniem ich chaotycznego charakteru630
 
3.1995Socha Grzegorz  Zmiany anizotropii plastycznej metali w czasie 
4.1988Piwnik Michał  Uwzględnienie wzmocnienia w rozwiązaniach plastyczności w płaskim stanie odkształcenia 
5.1988Kowalewski Zbigniew  Wpływ wtórnej anizotropii plastycznej na pełzanie metali w złożonym stanie naprężenia 
6.1984Waniewski Maciej  Wpływ kierunku i wartości wstępnej deformacji plastycznej na pełzanie metalu 
7.1979Piwnik Jan  Metody obliczeń złożonych procesów obróbki plastycznej w świetle badań doświadczalnych 

Recent publications
1.Rutecka A., Grzywna P., Dietrich L., Damage Detection of AA2124/SiC Metal Matrix Composites Using Electronic Speckle Pattern Interferometry, SOLID STATE PHENOMENA, ISSN: 1012-0394, DOI: 10.4028/www.scientific.net/SSP.240.122, Vol.240, pp.122-127, 2016
Abstract:

Metal matrix composites (MMCs) with aluminium alloy AA2124 matrix reinforced with 17 and 25% of SiC were investigated. Symmetric tension-compression fatigue tests at ambient temperature and tensile creep tests at elevated temperature were carried out. Specimens were subjected to fatigue or creep loading conditions. Tests were stopped after given number of cycles or strain values respectively. Electronic Speckle Pattern Interferometry (ESPI) was used in order to detect damage under fatigue and creep conditions. Strain fields were observed on specimens’ surfaces to localise strain concentrations that would indicate areas of damage development.

Keywords:

Creep, Damage, ESPI (Electronic Speckle Pattern Interferometry), Fatigue, MMC (Metal Matrix Composite)

Affiliations:
Rutecka A.-IPPT PAN
Grzywna P.-IPPT PAN
Dietrich L.-IPPT PAN
2.Rutecka A., Kowalewski Z.L., Makowska K., Pietrzak K., Dietrich L., Fatigue damage of Al/SiC composites – macroscopic and microscopic analysis, ARCHIVES OF METALLURGY AND MATERIALS, ISSN: 1733-3490, DOI: 10.1515/amm-2015-0016, Vol.60, No.1, pp.101-105, 2015
Abstract:

The results of comparative examinations of mechanical behaviour during fatigue loads and microstructure assessment before and after fatigue tests were presented. Composites of aluminium matrix and SiC reinforcement manufactured using the KoBo method were investigated. The combinations of two kinds of fatigue damage mechanisms were observed. The first one governed by cyclic plasticity and related to inelastic strain amplitude changes and the second one expressed in a form of ratcheting based on changes in mean inelastic strain. The higher SiC content the less influence of the fatigue damage mechanisms on material behaviour was observed. Attempts have been made to evaluate an appropriate fatigue damage parameter. However, it still needs further improvements.

Keywords:

fatigue, damage, metal matrix composites, microstructure

Affiliations:
Rutecka A.-IPPT PAN
Kowalewski Z.L.-IPPT PAN
Makowska K.-Motor Transport Institute (PL)
Pietrzak K.-other affiliation
Dietrich L.-IPPT PAN
3.Kowalewski Z.L., Dietrich L., Socha G., Experimental investigation of thin brass sheets under tension-compression cyclic loading, JOURNAL OF THEORETICAL AND APPLIED MECHANICS, ISSN: 1429-2955, DOI: 10.15632/jtam-pl.53.3.757, Vol.53, No.3, pp.757-762, 2015
Abstract:

Strength and durability of thin-walled structures are usually calculated with the use of computer simulations. To perform such simulations using Finite Element Method, characteristics of a material subjected to monotonic tension or compression and tension-compression cyclic loading are necessary. Experimental determination of such kind of characteristics is usually performed on specimens cut out from a metal or composite thin sheet. Problems associated with testing on flat specimens under large deformation are discussed in this paper. A new design of fixture proposed by the authors for this kind of testing is shortly described. The results of investigations carried out on brass using the new fixture for flat specimens testing are also presented.

Keywords:

fixture, large deformations, tension-compression tests, thin metal sheet

Affiliations:
Kowalewski Z.L.-IPPT PAN
Dietrich L.-IPPT PAN
Socha G.-other affiliation
4.Socha G., Dietrich L., A fatigue damage indicator parameter for P91 chromium-molybdenum alloy steel and fatigue pre-damaged P54T carbon steel, FATIGUE AND FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, ISSN: 8756-758X, DOI: 10.1111/ffe.12104, Vol.37, pp.195-205, 2014
Abstract:

Two grades of structural steel were subjected to fully reversible, constant stress amplitude cyclic loading. The local strain response of the material was measured and recorded during the test, with the applied testing technique enabling the monitoring of hysteresis loop variation for the narrowest cross-section of the hourglass specimen. Changes in hysteresis loop width, representing the local inelastic response of the material, were recorded in order to monitor the density of structural imperfections. Material ratcheting behaviour was observed as changes in the mean strain for selected load cycles. Ratcheting was attributed to local deformation of the material in the vicinity of imperfections such as voids or inclusions, as well as deformation induced by the propagation of microcracks. Definitions of a damage indicator parameter and damage parameter were proposed. The fatigue behaviour of the two investigated grades of steel was finally illustrated in the form of damage curves for different stress amplitudes and for undamaged and fatigue pre-damaged material.

Affiliations:
Socha G.-other affiliation
Dietrich L.-IPPT PAN
5.Dietrich L., Socha G., Kowalewski Z.L., Anti-buckling Fixture for Large Deformation Tension–Compression Cyclic Loading of Thin Metal Sheets, STRAIN, ISSN: 0039-2103, DOI: 10.1111/str.12078, Vol.50, pp.174-183, 2014
Abstract:

Determination of cyclic properties of a material used for many engineering structures, e.g. airframes, requires preparation of specimens from two-dimensional, shell structures. A specimen must be cut out from the structure component in the way allowing application of a load corresponding to that reflecting service cases. In order to fulfil this requirement, tension–compression testing of the flat specimen is necessary to obtain credible data. Problems associated with such kind of testing are discussed in this paper. In the first part, an extensive review of the anti-buckling fixtures developed up to now is given. Several representative solutions are discussed, with special emphasis on the technique limitations. In the second part of the paper, detailed description of the proposed design is given. Finally, the results of preliminary tests carried out using new fixture to mount the flat specimens cut from steel sheets are presented. Application of the proposed testing technique allowed tension–compression tests to be performed at the displacement amplitude within the range ±5 mm what corresponds to the maximum strain amplitude of ±0.4 for the specimen gauge length to be equal 12.5 mm. Taking into account all data captured by means of new fixture, one can conclude that the technique is promising with respect to providing data for modelling of cyclic deformation behaviour for shell structures.

Keywords:

buckling, cyclic loading, fixture, thin sheets

Affiliations:
Dietrich L.-IPPT PAN
Socha G.-other affiliation
Kowalewski Z.L.-IPPT PAN
6.Ziółkowski A., Luckner J., Dietrich L., On Conditioning of Resistive Strain Gage Channel Connected in Quarter Bridge Configuration in Measurement of Moderately Large Strains, EXPERIMENTAL TECHNIQUES, ISSN: 0732-8818, DOI: 10.1111/ext.12107, Vol.1, pp.1-16, 2014
Abstract:

In response to engineering needs of measuring moderate or large strains in metallic structures’ progress in resistance strain gages, technology resulted in widening the measurement range of this type of sensors to a range of 10–15%. For precision strain measurement applications, especially when a considerable number of measurement points are involved, single strain gage sensors are commonly used in quarter Wheatstone bridge configurations. Extension of measurement range to moderate strains requires taking into account inherent nonlinearities in signal transfer functions of the elements present in measurement chain. This work discusses in detail the most important ones, that is resistive gage sensor and quarter bridge measurement configuration nonlinearities to indicate that they are of the same order for moderate strains. Quite straightforward, shunt calibration procedure, taking into account these nonlinearities, is delivered or proposed enabling elimination of systematic errors. Thus, optimum accuracy of strain measurements matching the characteristics of components of strain measurement system can be conveniently achieved upon following simple steps. Inverse hyperbolic tangent—ϵLn =tanh−1(2 ∙e0/Eex)—linking scalar logarithmic strain and bridge reduced output voltage is shown to be a transfer function of strain measurement system with gage sensor in quarter bridge configuration for moderate or large strains.

Keywords:

Experimental Data Acquisition, Data Processing, Nonlinear Transfer Functions, Nonlinear Signal Conditioning, Experimental Strain/Stress Analysis, Accurate Finite Strain Measurements, Resistance Strain Gages, Nonlinear Sensors, Small/Technical Strain, Logarithmic/Natural Strain, Moderate Strains, Quarter Bridge Configuration, Wheatstone Bridge Circuits, Shunt Calibration, Scaling Amplifier Gain

Affiliations:
Ziółkowski A.-IPPT PAN
Luckner J.-IPPT PAN
Dietrich L.-IPPT PAN
7.Dietrich L., Socha G., Accumulation of Damage in A336 GR5 Structural Steel Subject to Complex Stress Loading, STRAIN, ISSN: 0039-2103, Vol.48, pp.279-285, 2012
Abstract:

Changes in the mechanical characteristics of the structural steel because of fatigue damage accumulation are investigated in this article. Cyclic loading was performed in a complex stress state. Tubular specimens were loaded by axial force and torque, with loading performed along proportional and non-proportional paths in the strain space. Material characteristics in the form of the stress–strain curve and yield surface were determined in the ‘as received’ state and after cyclic loading. It was found that accumulation of the fatigue damage because of cyclic loading in a complex stress state along proportional and non-proportional paths in the strain space is manifested by the increase in inelastic response. The rate of damage was found to be higher for non-proportional (circular) loading paths than that for proportional loading with the same strain amplitude.

Keywords:

complex stress state, damage accumulation, fatigue, strain space, yield surface

Affiliations:
Dietrich L.-IPPT PAN
Socha G.-other affiliation
8.Dietrich L., Grzywna P., Kukla D., Wykorzystanie metod optycznych do lokalizacji uszkodzeń zmęczeniowych, PRZEGLĄD SPAWALNICTWA, ISSN: 0033-2364, Vol.13, pp.16-18, 2012
Abstract:

Monitorowanie zjawisk związanych ze zmęczeniem materiałów jako procesu inicjowanego lokalnie wymaga całopolowych obserwacji deformacji zachodzących pod wpływem obciążeń zmęczeniowych. Metoda elektronicznej interferometrii plamkowej (ESPI) pozwala z dużą precyzją (przy zachowaniu stabilności układu pomiarowego) określić rozkład odkształceń na powierzchni próbki i tym samym wskazać miejsca koncentracji naprężeń wywołanych karbem (strukturalnym, geometrycznym). Możliwa jest także ocena rozwoju tych deformacji w kolejnych cyklach zmęczenia aż do utworzenia pęknięcia i dekohezji próbki. Bieżący pomiar odkształceń w strefie ich lokalizacji pozwala na ilościową ocenę dynamiki rozwoju uszkodzenia zmęczeniowego w badanym materiale.

Affiliations:
Dietrich L.-IPPT PAN
Grzywna P.-IPPT PAN
Kukla D.-IPPT PAN
9.Kowalewski Z.L., Dietrich L., Kukla D., Grzywna P., Szymczak T., Parametry uszkodzenia w procesie zmęczenia oraz ich miary, ENERGETYKA, PROBLEMY ENERGETYKI I GOSPODARKI PALIWOWO-ENERGETYCZNEJ, ISSN: 0013-7294, Vol.65, No.11 (701), pp.706-710, 2012
10.Rutecka A., Kowalewski Z.L., Pietrzak K., Dietrich L., Rehm W., Creep and Low Cycle Fatigue Investigations of Light Aluminium Alloys for Engine Cylinder Heads, STRAIN, ISSN: 0039-2103, DOI: 10.1111/j.1475-1305.2010.00779.x, Vol.47, No.Suppl. 2, pp.374-381, 2011
Abstract:

An influence of the chemical composition, porosity and ageing on mechanical behaviour of light, multifunctional aluminium alloys (AlSi8Cu3 and AlSi7MgCu0.5) subjected to creep and low cycle fatigue (LCF) was investigated. The materials were tested to verify their applicability as the cylinder heads in car engines. During creep tests, a strain response of the materials was observed under a range of the step-increased stresses and different temperatures. The LCF tests were carried out under strain control in three blocks of 100 cycles each with a constant strain amplitude. The results of creep and LCF tests were analysed with regard to chemical composition, type of porosity and ageing of the materials tested. An influence of porosity on the creep resistance and lifetime was considered. The results of the LCF tests were compared for the materials in the as-received state and after ageing. An experimental evaluation of cyclic behaviour because of the LCF was carried out to check whether the hardening or softening effects can be observed in the materials. Taking into account the various history of loading, a stress response of the materials was investigated.

Keywords:

creep, cylinder heads, fatigue, light alloys

Affiliations:
Rutecka A.-IPPT PAN
Kowalewski Z.L.-IPPT PAN
Pietrzak K.-other affiliation
Dietrich L.-IPPT PAN
Rehm W.-Daimler AG (DE)
11.Dietrich L., Radziejewska J., The fatigue damage development in a cast Al–Si–Cu alloy, MATERIALS AND DESIGN, ISSN: 0261-3069, DOI: 10.1016/j.matdes.2010.05.045, Vol.32, No.1, pp.322-329, 2011
Abstract:

The experimental identification of fatigue damage mechanisms and evaluation of their development rate, based on changes in material respond on cycle loading, has been presented in the work. The research has been conducted on hyper-eutectic cast alloy AlSi8Cu3. The microstructure and fracture analyses were performed. The high cycle fatigue tests were conducted with frequency of 20 Hz under constant nominal stress amplitude with monitoring the strain response of material during the test. The ratcheting was found as the main mechanism of the fatigue damage. It was established that the linear fatigue accumulation law should not be used for fatigue life prediction in case of the tested cast aluminum alloy

Keywords:

Cast aluminum alloy, Fatigue test, Fatigue damage

Affiliations:
Dietrich L.-IPPT PAN
Radziejewska J.-IPPT PAN
12.Szymczak T., Kowalewski Z.L., Dietrich L., Experimental analysis of creep and fatigue of light multifunctional aluminium alloys, MATERIALS RESEARCH INNOVATIONS, ISSN: 1432-8917, Vol.15, pp.53-56, 2011
Abstract:

The paper presents experimental investigations of two light aluminium alloys (AlSi8Cu3 and AlSi7MgCu0 5) under loading conditions leading to the creep or fatigue processes. During the creep process, the strains were measured under selected tensile stresses and temperatures. An influence of a step loading during creep, at elevated temperature, on steady creep rate and a course of creep curve, was investigated. Moreover, an effect of porosity degree on creep of both aluminium alloys was also analysed. An influence of aging process at the elevated temperature was experimentally evaluated. Fatigue behaviour of materials was checked under strain control using cylindrical samples. The results of LCF tests were analysed for the materials subjected to three-stage sequence of loading at elevated temperature. A resistance to creep and fatigue processes of the AlSi8Cu3 was weaker than that obtained in the case of the AlSi7MgCu0 5.

Keywords:

Creep, Fatigue, Sequence loading, Aluminium alloys

Affiliations:
Szymczak T.-Bialystok University of Technology (PL)
Kowalewski Z.L.-IPPT PAN
Dietrich L.-IPPT PAN
13.Kukla D., Dietrich L., Ciesielski M., Ocena stopnia uszkodzenia eksploatacyjnego materiału rurociągu parowego na podstawie analizy zmian właściwości zmęczeniowych i mikrostruktury, ACTA MECHANICA ET AUTOMATICA, ISSN: 1898-4088, Vol.5, No.3, pp.55-60, 2011
Abstract:

W pracy dokonano oceny stopnia uszkodzenia eksploatacyjnego materiału próbek z elementów rurociągów pary wtórnie przegrzanej po 100 000 godzin pracy na podstawie zmian właściwości zmęczeniowych oraz zmian mikrostruktury. Dokonano testów zmęczenia wysokocyklowego dla zmiennej amplitudy naprężenia z uwzględnieniem rozwoju odkształceńśrednich i niesprężystych. Na tej podstawie opracowano parametry opisujące stopień zniszczenia materiału pod wpływem obciążeń cyklicznych dla próbek w stanie przed i po eksploatacji. Analiza porównawcza wyznaczonych współczynników pozwala oszacować procentowy stopień degradacji materiału próbek eksploatowanych. Wykonano badania metalograficzne z wykorzystaniem Elektronowej Mikroskopii Skaningowej, na podstawie których scharakteryzowano mikrostrukturalne zmiany wynikające z długotrwałej pracy w warunkach eksploatacji rurociągów energetycznych.

Affiliations:
Kukla D.-IPPT PAN
Dietrich L.-IPPT PAN
Ciesielski M.-other affiliation
14.Rutecka A., Kowalewski Z.L., Pietrzak K., Dietrich L., Makowska K., Woźniak J., Kostecki M., Bochniak W., Olszyna A., Damage development of Al/SiC metal matrix composite under fatigue, creep and monotonic loading conditions, Procedia Engineering, ISSN: 1877-7058, DOI: 10.1016/j.proeng.2011.04.236, Vol.10, pp.1420-1425, 2011
Abstract:

A consolidation of powders using the KOBO method at elevated temperature was elaborated for production of Al/SiC metal matrix composite (MMC). The observations of the mean strain and inelastic strain range during the force controlled high cycle fatigue (HCF) tests identified the ratcheting mechanism combined with mechanism characterized by cyclic plasticity. Damage parameters were calculated on the basis of strain signal acquisition during fatigue tests. Fatigue properties, creep resistance and life time of Al/SiC MMC were gradually improved with the increase of the SiC particles content. The microstructural observations of the material before and after tests were also performed.

Keywords:

MMC, KOBO method, fatigue, creep, monotonic loading, microstructure, damage

Affiliations:
Rutecka A.-IPPT PAN
Kowalewski Z.L.-IPPT PAN
Pietrzak K.-other affiliation
Dietrich L.-IPPT PAN
Makowska K.-Motor Transport Institute (PL)
Woźniak J.-other affiliation
Kostecki M.-other affiliation
Bochniak W.-other affiliation
Olszyna A.-other affiliation
15.Rutecka A., Dietrich L., Kowalewski Z.L., Evaluation of the heat treatment role for light aluminium alloys subjected to creep and low cycle fatigue, MATERIALS SCIENCE FORUM, ISSN: 0255-5476, DOI: 10.4028/www.scientific.net/MSF.638-642.455, Vol.638-642, pp.455-460, 2010
Abstract:

The AlSi8Cu3 and AlSi7MgCu0.5 cast aluminium alloy s of different composition and heat treatment were investigated to verify their applicability as cylinder heads in the car engines [1]. Creep tests under the step-increased stresses at different temperatures, and low cycle fatigue (LCF) tests for a range of strain amplitudes and temperatures were carried out. The results exhibit a significant influence of the heat treatment on the mechanical properties of the AlSi8Cu3 and AlSi7MgCu0.5. An interesting fact is that the properties strongly depend on the type of quenching.
Lower creep resistance (higher strain rates) and lower stress response during fatigue tests were observed for the air quenched materials in comparison to those in the water quenched. Cyclic hardening/softening were also observed during the LCF tests due to the heat treatment applied. The mechanical properties determined during the tests can be used to identify new constitutive equations and to verify existing numerical models.

Keywords:

creep, low cycle fatigue, aluminum alloys, heat treatment

Affiliations:
Rutecka A.-IPPT PAN
Dietrich L.-IPPT PAN
Kowalewski Z.L.-IPPT PAN
16.Dietrich L., Rutecka A., Kowalewski Z.L., Assessment of exploitation properties of cast aluminium alloys on the basis of creep and LCF investigations, Archive of Mechanical Engineering, ISSN: 0004-0738, Vol.LVI, No.4, pp.405-412, 2009
Abstract:

The paper presents experimental results of creep and low cycle fatigue (LCF) tests carried out on the as-received cast aluminium alloys with different chemical composition and porosity. The test programmes contain creep investigations under step-increased stresses at different temperatures, and cyclic plasticity under different strain amplitudes and temperatures

Keywords:

creep, low cycle fatigue, aluminium alloys

Affiliations:
Dietrich L.-IPPT PAN
Rutecka A.-IPPT PAN
Kowalewski Z.L.-IPPT PAN
17.Dietrich L., Lekszycki T., Turski K., Identyfikacja charakterystyki mechanicznej materiałów sprężystolepkich na podstawie danych doświadczalnych, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.13, pp.1-59, 1995
18.Dietrich L., Kowalewski Z.L., Rozwój anizotropowych własności miedzi pod wpływem deformacji plastycznej przy pełzaniu i monotonicznym obciążaniu, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.23, pp.1-42, 1994
19.Dietrich L., Kiryk R., Turski K., Zmiany anizotropii stopu aluminium pod wpływem wyżarzania, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.24, pp.1-40, 1994
20.Dietrich L., Kiryk R., Socha G., Śliwowski M., Identyfikacja plastycznej anizotropii stopu aluminium, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.26, pp.1-49, 1994
21.Dietrich L., Kowalewski Z.L., Śliwowski M., Zmiany parametrów anizotropii stopu aluminium pod wpływem deformacji cyklicznej, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.27, pp.1-48, 1994
22.Dietrich L., Kowalewski Z.L., Śliwowski M., Socha G., Charakterystyka cyklicznych właściwości stopu aluminium na podstawie badań w złożonym stanie naprężenia, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.29, pp.1-60, 1994
23.Dietrich L., Doświadczalne określenie anizotropii plastycznej metali, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.33, pp.1-20, 1994
24.Dietrich L., Turski K., Waniewski M., Dziankowski Z., Kiryk R., Technika badań właściwości mechanicznych materiałów w złożonym stanie naprężenia, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.34, pp.1-104, 1994
25.Dietrich L., Śliwowski M., Badanie wpływu prędkości odkształcania na właściwości mechaniczne stali 34 GS, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.14, pp.1-49, 1992
26.Dietrich L., Turski K., Analiza sposobów wyznaczania stałych materiałowych dla materiałów lepkosprężystych, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.28, pp.1-37, 1991
27.Dietrich L., Trąmpczyński W., Doświadczalne metody wyznaczania parć ośrodków sypkich w silosach, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.45, pp.1-119, 1988
28.Dietrich L., Trąmpczyński W., Wyznaczanie obciążeń narzędzi maszyn do robót ziemnych. - Algorytm i katalog programów obliczeń, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.21, pp.1-148, 1977
29.Dietrich L., Uwzględnienie wzmocnienia materiału w analizie złożonych procesów plastycznego płynięcia (Praca habilitacyjna), Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.53, pp.1-165, 1977
30.Dietrich L., Ocena przydatności metod teorii plastyczności do projektowania elementów maszyn na podstawie badań zmęczeniowych połączeń sworzniowych, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.38, pp.1-28, 1976
31.Dietrich L., Badania zmęczeniowe pasma z otworami, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.54, pp.1-39, 1976
32.Dietrich L., Hawrysz M., Śliwowski M., Trąmpczyński W., Zastosowania stanów granicznych do wyznaczania obciążeń maszyn do robót ziemnych, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.63, pp.1-162, 1975
33.Dietrich L., Szczepiński W., Plastic Yielding of Axially-symmetric Bars with Non-symmetric V-notch, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.5, pp.1-10, 1967

Conference papers
1.Libura T., Kowalewski Z.L., Dietrich L., Socha G., Anti-buckling system for flat specimens investigations under cyclic tension-compression, Materials Today: Proceedings, ISSN: 2214-7853, DOI: 10.1016/j.matpr.2016.03.045, No.3, pp.1045-1050, 2016
Abstract:

Modern automobile and airplane structures made of sheet metals or composites require usage of thinner and stronger materials. On the other hand, manufacturers are trying to reduce production costs by shortening the fabrication processes and by application of computed simulation for forming operation. Therefore, it is necessary to better understand and more accurately investigate deformation behaviour of sheet alloys. Testing of flat specimens under compression and cyclic tension-compression within large deformation procures a lot of problems. One of them is the buckling phenomenon. A new version of the device mounted in a standard testing machine was developed and geometry of the specimen for validation of the device was proposed. Specimens of DP690 steel with nominal thickness equal to 1.6 mm were investigated at ambient temperature. Tension-compression cyclic tests within a strain range ± 0.04 were executed starting in tension direction. It is shown that the results are repeatable.

Keywords:

Buckling, cyclic loading, fixture, thin sheets

Affiliations:
Libura T.-IPPT PAN
Kowalewski Z.L.-IPPT PAN
Dietrich L.-IPPT PAN
Socha G.-other affiliation
2.Kowalewski Z.L., Dietrich L., Kopeć M., Szymczak T., Grzywna P., Nowoczesne systemy optyczne w badaniach mechanicznych – budowa, działanie, zastosowania, XXII Seminarium NIENISZCZĄCE BADANIA MATERIAŁÓW, 2016-03-16/03-18, Zakopane (PL), pp.5-36, 2016
3.Kowalewski Z.L., Dietrich L., Socha G., Experimental investigation of thin metal sheets under tension-compression cyclic loading, ACAM 8, 8th Australasian Congress on Applied. Mechanics, 2014-11-23/11-26, Melbourne (AU), pp.1-10, 2014
Abstract:

Strength and durability of thin-walled structures are usually calculated with the use of computer simulations. To perform such simulations using Finite Element Method the characteristics of a material subjected to monotonic tension/or compression and tension-compression cyclic loading are necessary for example. Experimental determination of such kind of characteristics is usually performed on specimens cut out from metal or composite thin sheet. Problems associated with material testing on flat specimens under large deformation are discussed in detail by this paper. In the first part, a short review of the antibuckling fixtures developed up to now is given. Several representative solutions including the applied design are discussed, with special emphasis on the technique limitations. In the second part, the results of investigations carried out on steel and brass using the new fixture for the flat specimens testing are presented.

Keywords:

fixture, large deformations, tension-compression tests, thin metal sheet

Affiliations:
Kowalewski Z.L.-IPPT PAN
Dietrich L.-IPPT PAN
Socha G.-other affiliation
4.Rutecka A., Gutkiewicz P., Grzywna P., Dietrich L., Damage of AA2124/SiC metal matrix composite under fatigue conditions, ECCM16, 16th European Conference on Composite Materials, 2014-06-22/06-26, Seville (ES), pp.1-7, 2014
Abstract:

Fatigue tests of AA2124 based metal matrix composites (MMCs) with SiC particles reinforcement were carriedout. The MMCs were manufactured using powder metallurgy. Hysteresis loops were observed during subsequent cycles. Cyclic plasticity and ratcheting were identified as main fatigue damage mechanisms. Inelastic strain amplitude and mean inelastic strain were calculated to be used as fatigue damage indicators. Ultrasonic measurements during fatigue tests were performed but they did not allow to detect damage during fatigue test.

Keywords:

metal matrix composites, fatigue, damage

Affiliations:
Rutecka A.-IPPT PAN
Gutkiewicz P.-IPPT PAN
Grzywna P.-IPPT PAN
Dietrich L.-IPPT PAN
5.Kukla D., Dietrich L., Kowalewski Z.L., Grzywna P., Ocena rozwoju uszkodzeń zmęczeniowych w stalach eksploatowanych w energetyce, II Kongres Mechaniki Polskiej, 2011-08-29/09-02, Poznań (PL), pp.1-10, 2011
Abstract:

W pracy dokonano analizy wskaźników rozwoju uszkodzenia zmęczeniowego, opracowanych w oparciu o wyniki testów zmęczeniowych próbek ze stali P91, w stanie dostawy i po 80 000 godzin eksploatacji w warunkach pracy instalacji energetycznej. Wykonano badania zmęczeniowe dla dwóch typów próbek i wyznaczono funkcje zmiany parametrów uszkodzeń w zależności od liczby cykli przy różnych amplitudach naprężenia. Uzyskane wyniki wykorzystano do wyznaczenia klasycznej charakterystyki zmęczeniowej, ale również do wyznaczenia ewolucji uszkodzeń w zależności od liczby cykli. Wyniki wskazały na możliwość jej opisania przy pomocy dwóch makroskopowych wskaźników rozwoju zmęczenia. Pierwszy z nich to średnie odkształcenie w kolejnych cyklach obciążenia przy stałej amplitudzie naprężenia. Drugim, jest odkształcenie niesprężyste w cyklu obrazujące szerokość pętli histerezy w kolejnych fazach obciążenia ostałej amplitudzie naprężenia. Rozwój uszkodzenia wstali P91poddanej obciążeniom zmęczeniowym opisano stosując kombinację wyżej wymienionych wskaźników

Keywords:

badania zmęczeniowe, ewolucja uszkodzeń, wskaźniki uszkodzenia

Affiliations:
Kukla D.-IPPT PAN
Dietrich L.-IPPT PAN
Kowalewski Z.L.-IPPT PAN
Grzywna P.-IPPT PAN

Conference abstracts
1.Libura T., Kowalewski Z.L., Kowalczyk-Gajewska K., Dietrich L., Strain-hardening effect in thin-sheet magnesium alloy AZ31B under low cyclic loading, XII Konferencja „Nowe Kierunki Rozwoju Mechaniki”, 2017-03-22/03-25, Białystok - Supraśl (PL), pp.1-2, 2017
Abstract:

Optimization of sheet metal forming processes requires a very good knowledge of material forming ability. During the forming of industrial parts, very complex strain paths are usually observed and can affect the formability of the sheet. Therefore, it is necessary to better understand and more accurately investigate deformation behaviour of sheet alloys. It should be noted that material testing of flat specimens under compression within a large deformation range procures many difficulties, and the buckling phenomenon seems to be the most im-portant. This paper shows the results of tension-compression tests carried out on specimens made of ultralight magnesium alloys AZ31B with nominal thickness equal to 1 mm using the anti-buckling fixture to avoid buckling problem.

Keywords:

Bauschinger effect, cyclic loading, buckling, fixture, thin sheet

Affiliations:
Libura T.-IPPT PAN
Kowalewski Z.L.-IPPT PAN
Kowalczyk-Gajewska K.-IPPT PAN
Dietrich L.-IPPT PAN
2.Kowalewski Z.L., Dietrich L., Socha G., On the experimental techniques for thin sheets testing at large deformations, 9th German-Greek-Polish Symposium Recent Advances in Mechanics, 2016-09-04/09-09, Kolympari, Chania (GR), pp.41-42, 2016
Abstract:

Problems associated with material testing on flat specimens under large deformation due to compression or cyclic tension-compression are discussed. A short review of the anti-buckling fixtures developed up to now is given with special emphasis on the new fixture elaborated at the Institute of Fundamental Technological Research in Poland.

Affiliations:
Kowalewski Z.L.-IPPT PAN
Dietrich L.-IPPT PAN
Socha G.-other affiliation
3.Libura T., Kowalewski Z.L., Kowalczyk-Gajewska K., Dietrich L., Low cycle fatigue of a rolled magnesium alloy using anti-buckling fixture, DYMAT, 10th Workshop, 2016-08-24/08-26, Poznań (PL), pp.59-61, 2016
4.Kowalewski Z.L., Socha G., Dietrich L., Libura T., Thin sheet of brass testing under cyclic tension - compression using novel anti-buckling fixture, DAS 2015, 32nd Danubia-Adria-Symposium on Advances in Experimental Mechanics, 2015-09-22/09-25, Smokovec (SK), Vol.1, pp.128-129, 2015
5.Kowalewski Z.L., Dietrich L., Socha G., Anti-buckling system for flat specimens investigation under cyclic tension-compression, Plasticity 2015, 21st International Symposium on Plasticity and its Current Applications, 2015-01-04/01-09, Montego Bay (JM), pp.127-129, 2015
Abstract:

Problems associated with material testing on flat specimens under large deformation are discussed in this paper. An extensive review of the anti - buckling fixtures developed up to now is given first, and then detailed description of the proposed design is presented. Finally, the results of cyclic tests carried out using new fixture are studied

Affiliations:
Kowalewski Z.L.-IPPT PAN
Dietrich L.-IPPT PAN
Socha G.-other affiliation
6.Socha G., Dietrich L., Evolution of damage for p91 steel under cyclic load, SolMech 2014, 39th Solid Mechanics Conference, 2014-09-01/09-05, Zakopane (PL), pp.169-170, 2014
7.Rutecka A., Kowalewski Z.L., Pietrzak K., Dietrich L., Makowska K., Grzywna P., Woźniak J., Kostecki M., Bochniak W., Olszyna A., Damage analysis of Al(Mg)/SiC composites under fatigue conditions, 15th European Conference on Composite Materials, 2012-06-24/06-29, Wenecja (IT), No.1, pp.1-6, 2012
Abstract:

Fatigue tests and microstructural observations were carried out to perform damage analysis of Al/SiC and AlMg/SiC metal matrix composites ( MMCs ). The materials were manufactured using a KoBo method. Ratcheting was the dominant damage mechanism for Al/SiC and damage parameter on the basis of mean inelastic strain was calculated. For AlMg/SiC, in most cases, cyclic softening followed by hardening during subsequent cycles were noticed. Microstructural observations identified existence of SiC concentrations which influenced the volumetric fraction of defects after fatigue tests

Keywords:

metal matrix composites, fatigue damage, microstructure, KoBo method

Affiliations:
Rutecka A.-IPPT PAN
Kowalewski Z.L.-IPPT PAN
Pietrzak K.-other affiliation
Dietrich L.-IPPT PAN
Makowska K.-Motor Transport Institute (PL)
Grzywna P.-IPPT PAN
Woźniak J.-other affiliation
Kostecki M.-other affiliation
Bochniak W.-other affiliation
Olszyna A.-other affiliation
8.Rutecka A., Kowalewski Z.L., Pietrzak K., Dietrich L., Makowska K., Woźniak J., Kostecki M., Bochniak W., Olszyna A., AlMg/SiC metal matrix composites under fatigue and creep conditions, SolMech 2012, 38th Solid Mechanics Conference, 2012-08-27/08-31, Warszawa (PL), pp.146-147, 2012
9.Kukla D., Grzywna P., Dietrich L., The Development Dynamics of the located fatigue failure in the porous Silumin, 28th Danubia-Adria-Symposium on Advances in Experimental Mechanics, 2011-09-28/10-01, Siófok (HU), pp.1-2, 2011

Patents
Numer/data zgłoszenia patentowego
Ogłoszenie o zgłoszeniu patentowym
Twórca / twórcy
Tytuł
Kraj i Nazwa uprawnionego z patentu
Numer patentu
Ogłoszenie o udzieleniu patentu
pdf
398245
2012-02-27
BUP 18/13
2013-09-02
Dietrich L.E., Kowalewski Z.L., Socha G.M.
Przyrząd do badania wytrzymałościowych cienkich, płaskich próbek materiałów konstrukcyjnych, zwłaszcza blach
PL, Instytut Podstawowych Problemów Techniki PAN
-
-
-
359944
2003-04-30
BUP 22/04
2004-11-04
Socha G., Dietrich L.
Samocentrujący uchwyt do mocowania przedmiotów zaopatrzonych we współosiowe gwintowane końcówki
PL, Instytut Podstawowych Problemów Techniki PAN
199326
WUP 09/08
2008-09-30
359943
2003-04-30
BUP 22/04
2004-11-02
Socha G., Dietrich L.
Sposób określania stopnia uszkodzenia materiału konstrukcyjnego wywołanego obciążeniami eksploatacyjnymi
PL, Instytut Podstawowych Problemów Techniki PAN
204561
WUP 01/10
2010-01-29