Wyniki wyszukiwania - BazTech

1

Identification based on a finite element model of an impact force occurring on a composite structure

El-Bakari Abdelali, Khamlichi Abdellatif, Hanafi Issam

International Journal of Applied Mechanics and Engineering

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2023

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Vol. 28, no. 1

23--36

EN

Based on the inverse approach and the finite element method, the quality of a reconstructed signal is discussed in this work. The responses caused by a distributed impact on a portion of a composite structure can be recovered using dynamic analysis. The structure is thought to be complex and made up of two different-sized plates made of two different materials. The robustness of the inversion method was studied, as well as the sensitivity of the numerical method compared to modal truncation and sampling of the frequency response function (FRF). Once the FRF had been identified, regularized deconvolution as per generalized singular value decomposition was used to reconstruct the impact signal characteristics. It was revealed that only one mode is required to reconstruct the impact signal.

2

The Melting Process and its Impact on the Properties of High-Chromium Cast Iron and the Economic Calculation

Mędoń Jan, Szczęsny Andrzej, Ziółkowski Eugeniusz, Guzik Edward, Czarny M., Kopyciński Dariusz

Archives of Foundry Engineering

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2023

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Vol. 23, iss. 4

54--64

EN

The subject of this study is to show that the parameters of the melting process of high chromium cast iron affect the cost of casting and the properties of the cast iron. The analysis of the quality of the casting and its price was conducted in terms of the metal charge of high chromium cast iron. As is well known, in order to obtain the correct structure of the casting, and thus good strength properties, it is necessary to use clean batch components free of undesirable impurities. Unfortunately, the quality of the metal charge is proportional to its price. Thus, the use of expensive batch components offers the possibility of obtaining healthy and meeting the strength properties of castings. However, there is a flaw in this approach. And it is from the point of view of economics that production plants are forced to look for savings. Expensive feedstock materials are replaced by cheaper counterparts giving the possibility of obtaining castings with similar properties often, however, at the cost of increased inferior quality. It seems that a way out of this situation is to introduce a modification procedure into the alloyed iron manufacturing technology. The selected modifiers should affect the fragmentation of the structure of the primary austenite. At this point, it can be hypothesized that this will result in the elimination of hot cracking in high chromium cast iron. The industrial research carried out at the "Swidnica" Foundry Ltd. made it possible to show by means of the Althoff-Radtke method that by using the modification of the liquid metal of the so-called "inferior and cheaper" composition of the metal charge, a reduction in the occurrence of hot cracks and shrinkage cavities can be achieved. In addition, iron-niobium modification not only reduced the formation of casting defects in castings, but also slightly improved the impact strength of high-chromium cast iron. The work was written as part of an implementation PhD.

3

On the resistance of concrete hollow thin-walled high piers to rock collisions

Huang Yao

Archives of Civil Engineering

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2023

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Vol. 69, nr 3

187--197

EN

Concrete hollow thin-walled high piers (CHTWHPs) located in mountainous areas may be destroyed by the huge impact force of accidental rocks. The study focuses on analyzing the effects of rock impact on the pier, including its impact force, pier damage, dynamic response, and energy dissipation characteristics. The results show that: (1) Increasing the impact height led to a decrease in the peak impact force. Specifically, 15.5% decrease in the peak collision force is induced when the height of rock collision rises from 10 m to 40 m. (2) The damage mode of the pier’s collision surface is mainly oval damage with symmetrical center, radial damage on the side surface, and corner shear failure on the cross section. (3) The peak displacement of bridge pier increases with the increase of collision height. As the collision height increased from 10 m to 40 m, the bridge pier’s peak displacement also increased, rising by 104.2%. (4) The concrete internal energy gradually decreased with increasing collision height, dropping by 36.9% when the height of rock collision rises from 10 m to 40 m. The reinforcement internal energy showed an increase of 78%. The results of this study may provide reference for the rock collision resistance design of CHTWHPs.

4

Utilization of wrightia tinctoria nano seed fibers as a reinforcement in the preparation of epoxy-based composites

Syed Habibunnisa, Nerella Ruben, Madduru Sri Rama Chand, Reddy S Raja Gopal

Acta Innovations

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2022

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no. 45

5--17

EN

Natural seed fiber reinforced composite materials are replacing many conventional ones because of their excellent properties, less weight, easy availability, etc. Composite materials are used in many areas because of their superior features. Mechanical property is one of the vital parameters for choosing the material. The current investigation has revealed an importance of recently well-known Wrightia tinctoria nano seed fibers (WTNSFs), which are extracted physically. Wrightia tinctoria nano seed fiber reinforced composite was prepared with the epoxy resin by hand layup method. Epoxy resin is easy to handle and available at low cost. Mechanical tests are conducted reinforced composites of plain epoxy and WTNSFs to obtain strength properties like tensile, flexural, impact. Water absorption tests also performed on composites. Here, the developed composites are easy to handle, offered economically, and used primarily in marine applications due to less water absorption and good wax content. A comprehensive description of different tests and the properties of WTNSFs are studied and compared with the other existing natural fibers. This work showed that 35% combination of WTNSFs reinforced epoxy matrix offers enhanced mechanical properties with minimum water absorption compared with plain epoxy composites.

5

Influence of Centrifugal Shot Peening Parameters on the Impact Force and Surface Roughness of EN-AW 2024 Aluminum Alloy Elements

Skoczylas Agnieszka

Advances in Science and Technology. Research Journal

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2021

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Vol. 15, no 1

71--78

EN

This article presents the results of experimental studies on the influence of centrifugal shot peening parameters on the impact force Fu occurring during the machining of the EN – AW 2024 aluminum alloy. The surface roughness parameters Ra, Rt, Rpk, Rvk and surface topography were also analyzed. Centrifugal shot peening was carried out on the FV-580a vertical machining center using a centrifugal shot peening head. Variable parameters of the centrifugal shot peening were: tangential speed vg and infeed g. On the basis of the results obtained, it was found that the increase the tangential speed vg and the infeed g causes an increase of the impact force. After centrifugal shot peening, numerous micro-cavities were formed on the surface of the EN-AW 2024 aluminum alloy samples, which may can accumulate lubricants in their space. During centrifugal shot peening, low values impact force Fu were obtained, which confirms the legitimacy of using this method as a finishing machining of elements with low stiffness.

6

The Morphology of Impact Fracture Surfaces in Manganese Cast Steel Modified by Rare Earth Elements

Kasińska J.

Archives of Foundry Engineering

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2020

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Vol. 20, iss. 2

89--94

EN

The morphology of G20Mn5 specimens made of non-modified and rare earth metals (REM) modified cast steel was investigated. Molten metal was treated with a cerium-rich mischmetal contain 49.8% Ce, 21.8% La, 17.1% Nd, 5.5% Pr and 5.35% other rare earth metals making up the balance. The melting, quenching (920°C/water) and tempering (720°C/air) were performed under industrial conditions. Analysis included G20Mn5 cast steel fracture specimens subjected to Charpy V-notch impact testing at 20°C, -30°C and -40°C. The purpose of the analysis was to determine the influence of REM on the microstructure and mechanical properties of G20Mn5 cast steel and the REM effect on the morphology, impact strength and character of the fracture surfaces. In addition, a description of the mechanism by which fracture occurred in the two materials was proposed. The author demonstrated the beneficial effects of adding REM to molten steel, manifested by a 20 - 40% increase in impact toughness, depending on test temperature, as compared to the non-modified cast steel. Important findings included more than 100% increase in impact strength in comparison with the required impact toughness of 27J at -40C for heat treated steels (EN 10213).

7

Multimetal Stahl 1018 Composite – Structure and Strength Properties

Kalisz D., Arustmian A.

Archives of Foundry Engineering

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2020

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Vol. 20, iss. 4

77--82

EN

The series of experiments was performed on commercial polymeric composite material MultimetalStahl 1018. Strength tests were performed to determine the yield point of the material. The composite had the highest hardness at a temperature of 20°C. Hardness and microhardness were determined in further experiments. The adhesiveness of the material to metal surfaces and impact strength were also analyzed. The scanning electron microscopy and X-ray microanalysis methods were used for analyzing the microstructure of the material. Chemical composition of selected areas was analyzed, which allowed for a preliminary identification of metallic elements content in the composite. The microstructure of composite is highly non-homogeneous and particular phases are highly elongated and angular. The analyzed phase was enriched with silicon, aluminium, magnesium, iron and vanadium other phases enriched with metallic elements, e.g. molybdenum, titanium, vanadium and also oxygen as well as traces of cadmium and chromium. The results were presented in the form of photos and illustrations. The results confirmed the applicability of the composite as a binder for fixing mechanical and foundry devices.

8

Impact strength of squeeze casting AlSi13Cu2–CF composite

Zyska A., Konopka Z., Łągiewka M.

Archives of Foundry Engineering

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2020

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Vol. 20, iss. 2

49--52

EN

The paper presents the results of research on microstructure and impact strength of AlSi13Cu2 matrix composite reinforced by Ni-coating carbon fibers (CF) with a volume fraction of 5%, 10% and 15%. The composite suspensions were prepared using by stirring method and subsequently squeeze casted under different pressures of 25, 50, 75 and 100 MPa. As part of the study, fiber distribution in aluminum matrix was evaluated and variation in impact strength of composite as a function of the carbon fibers volume fraction and pressure applied were determined. It has been found that the presence of Ni coating on carbon fibers clearly improves their wettability by liquid aluminum alloy and in combination with the stirring parameters applied, composite material with relatively homogeneous structure can be produced. Charpy's test showed that the impact strength of composite reaches the highest value by carrying out the squeeze casting process at 75 MPa. In the next stage of research, it was found that the impact strength of composites increases with the increase of carbon fibers volume fraction and for 15% of fibers is close to 8 J/cm2. Observations of fracture surfaces have revealed that crack growth in the composites propagates with a quasi-cleavage mechanism. During the creation of the fracture, all fibers arranged perpendicular to its surface were sheared. At the same time, the metal matrix around the fibers deformed plastically creating characteristic ductile breaks. The fracture surface formation through the fibers indicates a cohesive and strong connection of the reinforcement with the matrix. In addition to the phenomena mentioned, debonding the fiber-matrix interfaces and the formation of voids between components were observed on the fracture surface.

9

Research of dynamic processes of the system “Vehicle – Track” using the new method of vehicle wheel with metal scale

Bogdevičius M., Žygienė R.

Eksploatacja i Niezawodność

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2018

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Vol. 20, no. 4

638--649

EN

Mathematical models of vehicle wheel with metal scales are introduced in this article. When analysing the interaction between vehicle wheel with a metal scale and rail in the system “Vehicle – Track”, the changes of the kinematic and dynamic parameters of the wheel and rail contact points in time are examined, depending on the height of the 2 mm metal scale, when the length of the metal scale is 100 mm and the speed of movement is V = 40 - 100 km/h. The results obtained after the research of the system “Vehicle – Track”, when the wheel has a metal scale, help to better understand and evaluate the impact of metal scale on wheel on dynamic loads of rail and vehicle and the regularities of their movement. The appearance of a metal scale on the wheel’s surface causes technical and maintenances problems for the rolling stock. Railway standards limit the speed of movement that depends on a certain size of metal scale.

PL

W niniejszym artykule przedstawiono modele matematyczne koła pojazdu szynowego z powstałą w wyniku zużycia metalową łuską. Analizując oddziaływania pomiędzy kołem pojazdu z łuską a szyną w układzie "pojazd–tor", badano zmiany kinematycznych i dynamicznych parametrów punktów kontaktu koła z szyną zachodzące w czasie, w zależności od wysokości metalowej łuski (2mm), przy długości łuski 100 mm i zakresie prędkości ruchu pojazdu V = 40–100 km/h. Wyniki uzyskane w badaniu układu "pojazd–tor" dla kół na powierzchni których powstała metalowa łuska, umożliwiają lepsze zrozumienie oraz ocenę wpływu łuski na dynamiczne obciążenia szyny i pojazdu oraz prawidłowości ruchu pojazdu. Pojawienie się metalowej łuski na powierzchni koła powoduje problemy techniczne i obsługowe w utrzymaniu ruchu taboru kolejowego. Normy kolejowe ograniczają prędkość ruchu pojazdów szynowych, uzależniając ją od rozmiaru łuski.

10

Changes in Impact Strength and Abrasive Wear Resistance of Cast High Manganese Steel Due to the Formation of Primary Titanium Carbides

Tęcza G., Zapała R.

Archives of Foundry Engineering

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2018

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Vol. 18, iss. 1

119--122

EN

Cast high-manganese Hadfield steel is commonly used for machine components operating under dynamic load conditions. Their high fracture toughness and abrasive wear resistance is the result of an austenitic structure, which - while being ductile - at the same time tends to surface harden under the effect of cold work. Absence of dynamic loads (e.g. in the case of sand abrasion) causes rapid and premature wear of parts. In order to improve the abrasive wear resistance of cast high-manganese steel for operation under the conditions free from dynamic loads, primary titanium carbides are produced in this cast steel during melting process to obtain in castings, after melt solidification, the microstructure consisting of an austenitic matrix and primary carbides uniformly distributed therein. After heat treatment, the microhardness of the austenitic matrix of such cast steel is up to 580 μHV20 and the resulting carbides may reach even 4000 μHV20. The impact strength of this cast steel varies from 57 to 129 and it decreases with titanium content. Compared to common cast Hadfield steel, the abrasive wear resistance determined in Miller test is at least twice as high for the 0.4% Ti alloy and continues growing with titanium content.

11

Effect of the Annealing Temperature on the Microstructure and Properties of Ausferritic Nodular Cast Iron

Gumienny G., Klimek L., Kurowska B.

Archives of Foundry Engineering

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2016

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Vol. 16, iss. 3

43--48

EN

The paper presents the microstructure and selected properties of ausferritic nodular cast iron annealed at the temperature 520 and 550°C. This choice was dictated by the temperatures used in the practice of nitriding. Nodular graphite in cast iron was obtained with use of Inmold process. Cast iron containing molybdenum and copper ensuring obtaining an ausferrite in the cast iron matrix without the use of heat treatment of castings was tested. The effect of annealing temperature on the microstructure and the kind of fracture of the ausferritic nodular cast iron was presented. The effect of an annealing temperature on hardness, impact strength and the microhardness of ausferritic nodular cast iron matrix was shown too. The lamellar structure of phases in the cast iron matrix after annealing has been ascertained. There has been an increase in hardness of an annealed cast iron and microhardness of its matrix. The reduction in the impact strength of the cast iron annealed at 520 and 550°C was approximately 10-30%. Both an increase in the hardness of cast iron as well as an decrease in its impact strength is probably due to the separation of secondary carbides during the heat treatment.

12

The Effect Of Strain Rate On The Mechanical Properties And Microstructure Of The High-Mn Steel After Dynamic Deformation Tests

Jabłońska M. B., Śmiglewicz A., Niewielski G.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 2A

577--580

EN

W pracy przedstawiono wyniki wstępnych badań dynamicznego rozciągania wysokomanganowej stali gatunku X20MnAlSi16-3-3. Badania przeprowadzono na młocie rotacyjnym, który posiada możliwość realizacji prób dynamicznego rozciągania i udarowego zginania w zakresie prędkości liniowej elementu wymuszającego od 5÷40 m/s. Badana stal charakteryzuje się bardzo dobrymi właściwościami mechanicznymi. Wyniki badań uzyskano na podstawie statycznej próby rozciągania, próby dynamicznego rozciągania na młocie rotacyjnym oraz pomiaru twardości metodą Vickersa. Przeanalizowano powierzchnie przełomów powstałych w miejscu zerwania podczas prób rozciągania, które wskazują na obecność przełomów transkrystalicznych ciągliwych. Badania strukturalne wykonano z wykorzystaniem techniki mikroskopii świetlnej, skaningowej mikroskopii elektronowej i skaningowej transmisyjnej mikroskopii elektronowej. Przeprowadzone badania substruktury ujawniły obecność mechanizmu bliźniakowania mechanicznego, indukowanego w warunkach dużych prędkości odkształcenia.

13

Application of Small Punch Test Method in Studies of the 14MoV63 Steel Before and After Revitalisation

Kłaput J.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 1

47--50

EN

The paper presents the results of studies of the chromium-molybdenum-vanadium steel designed for operation at elevated temperatures. The material was examined after long-term operation and after the revitalising heat treatment. Studies were performed by conventional methods and small punch test. Curves of ductile-brittle transition were plotted from the Charpy V-notch impact tests and were next compared with the curves of sudden loss of ductility obtained in the small punch test. Additionally, for the material before and after revitalisation, the values of temperatures Tpk and Tnuc were calculated using the method of inflection point.

PL

W pracy przedstawiono wyniki badań stali chromowo-molibdenowo-wanadowej przeznaczonej do pracy przy podwyższonych temperaturach. Materiał badano w stanie po wieloletniej eksploatacji i po obróbce cieplnej rewitalizującej. Badania prowadzono z zastosowaniem metod konwencjonalnych oraz przy pomocy metody small punch. Sporządzono krzywe przejścia plastyczno-kruchego z próby udarności Charpy V i porównano je z krzywymi nagłej utraty ciągliwości z próby small punch. Dla materiału przed i po rewitalizacji określono wartości temperatur Tpk i Tnuc stosując metodę punktu przegięcia.

14

Obciążenie suwnicami pomostowymi według PN-EN 1991-3 – przykład obliczeniowy

Swierczyna S.

Nowoczesne Hale

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2014

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Nr 1

39--43

PL

Zapisy normy PN-EN 1991-3 [4] dotyczące wyznaczania oddziaływań wywołanych suwnicami pomostowymi omówiono w „Nowoczesnych Halach” nr 2/2013 [2]. Obecnie komentarz ten zostanie uzupełniony o przykład liczbowy.

15

Evaluation of selected factors and their interactions’ significance on impact force magnitude

Marasová D., Ambriško L., Grendel P., Andrejiová M.

Cuprum : czasopismo naukowo-techniczne górnictwa rud

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2014

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nr 3

5--15

EN

The article is focused on the analysis of experimental research conveyor belt quality in terms of their breakdown resistance by the Design of Experiments method. The planned experiment consists in the determination of the experiment’s goal, the selection of the response, and the determination of the factors, proposal and execution of the experiment, and assessment of the significance of the factors’ effects or interaction by the t-test, whereby at output it is expressed by p-value. We use the Pareto chart and Normal probability plot to evaluate factors’ effect and their interactions. Finally, the experiment is evaluated and the results are analyzed using the regression model, which applies input and output variables to the relation. The regression model presents the complete multifactor experiment that contains main factors and interactions.

PL

Celem artykułu jest analiza wyników eksperymentalnych badań jakości taśm przenośnikowych ze względu na odporność na przebicie, z wykorzystaniem metody planowania eksperymentu. Metoda planowania eksperymentu składa się z identyfikacji obiektu i celu badań, wyboru wyjściowych i zmiennych oraz liczby ich poziomów, planowania i wykonania eksperymentu oraz oceny istotności poszczególnych czynników oraz ich interakcji z wykorzystaniem testu t, której miarą jest wartość wskaźnika – p. W celu określenia istotności poszczególnych zmiennych i związków pomiędzy nimi zastosowano wykres Pareto i wykres normalnego rozkładu prawdopodobieństwa. W podsumowaniu opisano przeprowadzony eksperyment oraz analizę wyników za pomocą modelu regresji, wykazującego związki pomiędzy zmiennymi wejściowymi i wyjściowymi. Model regresyjny przedstawia kompletny wieloczynnikowy eksperyment obejmujący podstawowe zmienne oraz ich interakcje.

16

Impact behaviour of the Japanese sword

Daimaruya M., Kobayashi H.

Engineering Transactions

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2012

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Vol. 60, iss. 2

101-112

EN

The Japanese sword is a weapon peculiar to Japan. The present study is concerned with the joint between tohshin (blade) and tsuka (hilt) of the Japanese sword. Only one mekugitake (retaining peg made of bamboo) with about 5mm in diameter holds the tang in the hilt. However a slender mekugi might not be broken, even in the case of violent sword-fighting. This fact has been historically demonstrated in many battles by Japanese swords. In this study it is examined theoretically and experimentally from the viewpoint of impact engineering why a mekugi used in Tachi and Katana may not be broken. As a result, it is found that such a strong force as breaking a mekugi-take does not act on it, because of the location of mekugiana (a hole for mekugi) in the tang, which has been made in the Japanese sword by following the traditional code of sword-smiths.

17

Precipitation of Laves phase Fe2Mo type in HSLA steel with copper addition and high content of molybdenum

Bogucki R., Miernik K., Pytel S.

Archives of Foundry Engineering

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2010

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Vol. 10, iss. 3 spec.

213--218

EN

The results of mechanical properties and microstructure of low-carbon copper bearing steel after quenching and tempering at temperature range of processing precipitation of particles rich in copper and particles intermetallic phase are presented in this paper. When content molybdenum increases in tempering temperature range from 550°C to 600°C that decrease of the impact energy measured at room temperature was observed. Microstructure analysis was conducted by transmission electron microscope (TEM) and was disclosed the occurrence of Fe2Mo Laves phase on crystallites boundaries of retained austenite. Observed sudden drop of ductility in higher-molybdenum content steels (1,88 % and 2,94 %) should be connected with occurrence precipitation processes of the hard and brittle Laves phase in range of discussion tempering temperatures.

18

Ewaluacja systemów pomiaru siły uderzeniowej w celu oceny urazów podpancerzowych powstających pod nieprzebitymi hełmami

Anctil B., Bourget D., Pageau G., Rice K., Lesko J.

Techniczne Wyroby Włókiennicze

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2006

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R. 14, nr 1/2

25-36

PL

Wraz z pojawieniem się nowych technologii balistycznej ochrony pojawiła się możliwość nowoczesnego projektowania hełmów o lepszej efektywności osłony przed kulami o wysokiej energii. Podczas gdy nowe hełmy są w stanie chronić przed takim zagrożeniem, znaczące podpancerzowe deformacje mogą stanowić obciążenie wystarczająco silne, by spowodować poważne urazy. Poprzednia praca przeprowadzona przez University of Virginia dla U.S. Army Natick Soldier Genter oraz przez Defence R&D Canada-Valcartier wykazała korelację między urazami głowy oraz mierzoną siłą wywieraną na czaszkę w rezultacie niepenetrującego uderzenia pocisku w hełm. Bieżące wysiłki, korzystając z tamtych osiągnięć, prowadzą do rozwoju metodologii testowej w celu włączenia jej poprawionej wersji do standardu NIJ 0106.01 i przyszłych kanadyjskich specyfikacji hełmów balistycznych. Została zaprezentowana ocena systemów przeznaczonych do instalowania w zmodyfikowanej makiecie głowy Hybrid III i służących do mierzenia potencjalnych sił działających pod pancerzem w wyniku uderzenia. Porównywano mierniki z polifluorku winylidenu (PVDF) i miniaturowe piezoelektryczne ogniwa obciążnikowe. Instrumenty i metody były oceniane pod względem dokładności i powtarzalności w kontekście efektywności standardowych testów. Zostały podane wyniki doświadczalne i zalecenia dotyczące przyszłych prac.

EN

With the emergence of new technologies for ballistic protection, there now exists the possibility of having novel helmet designs with improved performance against high energy bullets. While the new helmets are capable of defeating these threats, significant behind armour deformation may still produce sufficient loading to the head to cause serious injury. Previous work at the University of Virginia for the U.S. Army Natick Soldier Center and at the Defence R&D Canada-Valcartier established a correlation between head injury and measured force on the skull as a result of nonpenetrating projectile impacts to a helmet. Current efforts comprise the development of a test methodology based on these findings to be potentially included in a revised version of the NIJ 0106.01 standard and future Canadian ballistic helmet specifications. An evaluation of potential behind armour impact force measurement systems to be installed in a modified Hybrid III headform is presented. Performances of polyvinylidine fluoride (PVDF) gauges and miniature piezo-electric load cells were compared. Instrumentation and methods were evaluated for accuracy and repeatability in the context of performance standard testing. Experimental results and recommendations for future work are presented.

19

A frequency - domain deconvolution approach for impact force waveform restoration with the use of one - point strain measurement

Kaczmarek Z.

Metrology and Measurement Systems

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2002

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Vol. 9, nr 1

3-17

EN

In the paper an impact force waveform restoration by means of deconvolution method is presented, which features a one-point strain measurement in a mechanical transducer. To determine the spectral transmittance of a section of the mechanical transducer necessary in the reconstruction process, strain waves propagating in the transducer are used: the incident, and the first reflected one, created by the impact. Restrictions concerning the impact duration as well as the strain gauge localization on the mechanical transducer are given, which assure the non interference of the above mentioned waves in the strain gauges. The reconstruction results of impact force waveformsgenerated during impacts of stell spheres in the front face of a steel bar are presented. The consistency of the obtained reconstruction results with the Hertz impact theory with respect to the duration and amplitude of the impact force was evaluated.

PL

W pracy przedstawiono metodę odtwarzania przebiegów siły uderzenia bazującą na technice deterministycznego odsplatania i jednopunktowym pomiarze odkształceń w przetworniku mechanicznym. Do wyznaczenia transmitancji widmowej odcinka przetwornika mechanicznego, potrzebnej w procesie odtwarzania, wykorzystywane są rozchodzące się w tym przetworniku fale odkształceń: bezpośrednia i pierwsza odbita, powstałe w wyniku uderzenia. Podano ograniczenia dotyczące czasu trwania uderzenia oraz lokalizacji tensometrów na przetworniku mechanicznym, które zapewniają nie nakładanie się wyżej wymienionych fal w tensometrach. Przedstawiono wyniki odtwarzania wyżej omówionym sposobem przebiegów siły uderzenia powstałych w efekcie sprężystych uderzeń stalowych kulek w powierzchnię czołową stalowego pręta. Oszacowano zgodność uzyskanych rezultatów odtwarzania w zakresie czasów trwania i amplitudy impulsu siły uderzenia z teorią uderzenia Hertza.