Wyniki wyszukiwania - BazTech

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Material characterization for numerical simulation of manufacturing of automotive part made of magnesium alloy

Pietrzyk Maciej, Kuziak Roman, Bzowski Krzysztof, Rauch Łukasz, Ambroziński Mateusz, Gronostajski Zbigniew, Chorzępa Władysław

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 1

72--81

EN

Evaluation of the possibility of substitution of steel part in the car body by the one made of AZ31 alloy was the main objective of the whole project. The objective of this paper was to determine the flow stress model, which accounts for the difference in the behavior of magnesium alloys during tension and compression. Tension tests on Zwick machine and compression tests on Gleeble 3800 were performed. Inverse analysis was applied to interpretation of the results of the tests. Separate numerical models for tension and compression were implemented into Abaqus software and simulations of the stamping were performed. Sensitivity of the results to the flow stress model was evaluated.

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Effect of Process Variables on Friction Stirred Microstructure and Surface Hardness of AZ31 Magnesium Alloy

Kim Jae-Yeon, Hwang Jung-Woo, Lee Seung-Mi, Hyun Chang-Young, Park Ik-Keun, Byeon Jai-Won

Archives of Metallurgy and Materials

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2019

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Vol. 64, iss. 3

907--911

EN

Effects of various friction stir processing (FSP) variables on the microstructural evolution and microhardness of the AZ31 magnesium alloy were investigated. The processing variables include rotational and travelling speed of the tool, kind of secondphase (i.e., diamond, Al2 O3 , and ZrO2 ) and groove depth (i.e., volume fraction of second phase). Grain size, distribution of second phase particle, grain texture, and microhardness were analyzed as a function of the FSP process variables. The FSPed AZ31 com-posites fabricated with a high heat input condition showed the better dispersion of particle without macro defect. For all composite specimens, the grain size decreased and the microhardness increased regardless of the grooved depth compared with that of the FSPed AZ31 without strengthening particle, respectively. For the AZ31/diamond composite having a grain size of about 1 μm, microhardness (i.e., about 108 Hv) was about two times higher than that of the matrix alloy (i.e., about 52 Hv). The effect of second phase particle on retardation of grain growth and resulting hardness increase was discussed.

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Spawanie blach ze stopu magnezu AZ31 metodą MIG w odmianie CMT

Kołodziejczak P., Cegielski P., Kolasa A.

Przegląd Spawalnictwa

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2015

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R. 87, nr 10

72--76

PL

W artykule omówiono technologiczne aspekty spawania blach ze stopu magnezu niskoenergetyczną metodą CMT. Badano złącza doczołowe blach o grubości 2 mm wykonanych ze stopu magnezu AZ31 z wykorzystaniem drutu elektrodowego o średnicy 1,2 mm, wytworzonego z tego samego materiału (stopu AZ31). Próby prowadzono na stanowisku zrobotyzowanym z zapewnieniem wysokiej powtarzalności procesu, przy różnych parametrach, w tym z wykorzystaniem specjalnych funkcji wspomagających zajarzenie i wstępną fazę spawania. Jakość złączy oceniano na podstawie badań wizualnych i mikroskopowych.

EN

The technological aspects of welding of magnesium alloy by low energy CMT method is discussed. Butt joints of thickness 2 mm made of magnesium alloy AZ31 were tested using the wire electrode of 1.2 mm diameter, made from the same material (alloy AZ31). Tests were carried out with the use of a robotic installation that assured a high repeatability of the process and the various parameters, including the use of special features enabling ignition and initial phase of welding. The quality of joints was evaluated on the basis of visual and microscopic inspection.

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Miniature specimen tensile testing of AZ31 alloy processed by ECAP

Procházka R., Džugan J., Kövér M.

Archives of Materials Science and Engineering

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2015

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Vol. 76, nr 2

134--139

EN

Purpose: Evaluation of bulk nanomaterials and ultra-fine grain structures consists mostly of metallographic evaluation and hardness measurement. The documentation of mechanical properties by hardness testing only might be very inaccurate due to the measurement error and sensitivity. Moreover the yield stress, ultimate tensile stress an elongation determined by tensile testing are more suitable for description of mechanical properties. This article promotes miniature tensile testing. Although the miniature tensile testing could be commonly used for description of mechanical properties in SPD materials, it is quite unknown. Design/methodology/approach: In this article the miniature tensile testing was used for determination. of mechanical properties anisotropy in AZ31 alloy processed by ECAP. The verification was performed by comparison of conventional and miniature tensile specimens of the non-deformed bulk material. Findings: From the experimental procedure and results low material consumption during sampling, sampling and measurement simplicity and possibility to measure the properties in various directions are denoted. Research limitations/implications: Future detailed investigation of secondary phase particles and dislocation-precipitate interaction should be performed. This investigation was not performed as it requires transmission electron microscopy. Such investigation will be performed only for chosen specimens to confirm discussed hypotheses. Practical implications: The paper promotes application of miniature tensile testing for determination of mechanical properties in SPD processed materials. Application of this methodology allows determination of mechanical properties from local volume, material save or preformation of several experiments from a single specimen. Originality/value: The finding might be valuable for researchers in SPD field. The originality of this paper is based on novel methodology and its applicability.

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Numerical analysis of AZ31 alloy extrusion process by the ECAE method

Bajor T., Krakowiak M., Dyja H.

Inżynieria Materiałowa

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2014

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Vol. 35, nr 2

75--77

EN

This paper presents the results of numerical analysis of temperaturevelocity conditions of deformation process of AZ31 magnesium alloy by ECAE (Equal Channel Angular Extrusion) method. Computations were made using the finite element method (FEM) in a 3D spatial deformation state, taking into account the thermal phenomenon that occurs during the development of the final product. The process of material extrusion through the angular channel of the die was analyzed at three different temperatures and for four values of the punch feed rate. Numerical investigations were carried out for one type of the die, in which the channels are arranged against each other at the right angle. The main aim of this study was to determine the most favourable parameters of the extrusion to obtain the finished product with good mechanical properties. The resulting rod with a diameter of 15 mm will serve as an input preform for further deformation processes. This paper presents the results of computer simulations of temperature, stress and strain tensor distribution in the material in dependence on the process conditions. The research has shown that the highest stress concentration in the analyzed extrusion process takes place at the corners of the angular die.

PL

W artykule przedstawiono wyniki badań numerycznych obejmujących analizę warunków temperaturowo-prędkościowych procesu odkształcania stopu magnezu AZ31 metodą wyciskania ECAE (Equal Channel Angular Extrusion). Obliczenia wykonano metodą elementów skończonych w warunkach przestrzennego stanu odkształcenia 3D z uwzględnieniem zjawisk cieplnych zachodzących podczas kształtowania wyrobu gotowego. Proces wyciskania materiału z wykorzystaniem matrycy z kanałem kątowym przeanalizowano w trzech wariantach temperaturowych oraz z zastosowaniem czterech prędkości posuwu stempla. Badania numeryczne przeprowadzono dla jednego rodzaju matrycy, w której kanały są ułożone względem siebie pod kątem prostym. Głównym celem przeprowadzonych badań numerycznych było określenie najkorzystniejszych parametrów przeciskania w celu uzyskania wyrobu gotowego o dobrych własnościach mechanicznych. Uzyskany wyrób jakim jest pręt okrągły o średnicy 15 mm będzie stanowił wsad do dalszych procesów przeróbki plastycznej. W pracy przedstawiono symulacje komputerowe rozkładu temperatury, tensora naprężeń oraz tensora odkształceń w badanym materiale w zależności od warunków prowadzenia procesu. Przeprowadzone badania wykazały, iż największa koncentracja naprężeń w analizowanym procesie wyciskania ma miejsce w narożach matrycy.

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Analiza numeryczna kształtowania stopu AZ31 sposobem prasowania obwiedniowego na ciepło

Samołyk G.

Hutnik, Wiadomości Hutnicze

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2009

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Vol. 76, nr 8

653-656

PL

Niniejszy artykuł przedstawia wyniki numerycznej analizy prasowania obwiedniowego stopu AZ31 na ciepło. Skupiono się na przewidywaniu pęknięć w kształtowanym materiale (określanego na podstawie kryterium Cockrofta-Lathama) oraz określeniu zakresu temperatury prasowania. W rozważaniach również zwrócono uwagę na zjawisko generowania ciepła w wyniku odkształceń plastycznych.

EN

This paper presents the results of numerical analysis of AZ31 alloy rotary forging. The simulation was curried out on the Deform- 3D application (FEM). There was considered, that the Cockroft&Latham’s criterion describes material fractures. There obtains the relationship between a workpice temperature and warm rotary forging of AZ31 alloy.