Wyniki wyszukiwania - Biblioteka Nauki

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Numeryczna analiza technologii obróbek HPT i SP z wykorzystaniem pakietu ANSYS LS-Dyna

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Byczkowska P. , Stegliński M. , Sawicki J.

Inżynieria Materiałowa

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2015

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tom Vol. 36, nr 6

433--438

PL

Opracowanie metodyki budowy i rozwiązywania modeli procesów wykorzystujących intensywną akumulację odkształceń SPD (severe plastic deformation) jest kluczowym zagadnieniem pozwalającym panować nad procesami technologicznymi. Wykorzystując symulacje komputerowe, można zgłębić wiedzę dotyczącą zjawisk fizycznych zachodzących podczas obróbki wyrobu oraz ich wpływu na właściwości mechaniczne obrabianego materiału. Analiza tych zjawisk umożliwia dobranie optymalnych parametrów procesu oraz sprawdzenie założeń i eliminację błędów już na etapie symulacji komputerowej, co pozwala na znaczne skrócenie czasu wdrożenia oraz obniżenia jego kosztów. Prezentowana praca dotyczy analizy numerycznej superpozycji naprężeń będących wynikiem procesu HPT (high-pressure torsion) i SP (shot peening). Do przeprowadzenia modelowania komputerowego szybkozmiennych i dynamicznych zjawisk wykorzystano oprogramowanie ANSYS LS-Dyna. W pracy przeanalizowano wpływ hybrydowej obróbki procesu HPT oraz SP na właściwości technologicznej warstwy wierzchniej lekkich stopów aluminium. Przeprowadzenie symulacji komputerowej pozwoliło na analizę superpozycji odkształceń, naprężeń oraz głębokość ich zasięgu w zależności od parametrów procesów.

EN

Development of the construction methodology and solving models which uses severe plastic deformation (SPD) is a key issue that allows to control technological processes. Using computer simulations, it is possible to expand knowledge about physical phenomena that occur during processing, and their effect on the mechanical properties of the treated material. Analysis of these phenomena enables selection of optimum process parameters, test assumptions and eliminating errors at computer simulation stage, which allows to significantly reduce implementation time and lower its cost. This work concerns the numerical analysis of superposition of stresses resulting from the high-pressure torsion (HPT) process and shot peening (SP) process. To carry out computer modelling of fast and dynamic phenomena ANSYS LS-Dyna software were used. The study analyzed the impact of hybrid machining process of HPT and SP on the technological properties of lightweight aluminium alloys surface layer. Carrying out computer simulation allowed the analysis of superposition distribution of deformation, stress and depth of coverage depending on process parameters.

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Analiza numeryczna stanu naprężeń własnych stopu Al-Mg-Mn-Sc-Zr poddanego umocnieniu powierzchniowemu poprzez kulowanie

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Stegliński M. , Byczkowska P. , Sawicki J.

Biuletyn Wojskowej Akademii Technicznej

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2015

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tom Vol. 64, nr 1

127-137

PL

W niniejszej pracy zaprezentowane zostały wyniki analizy stanu naprężeń własnych w stopie Al-Mg5%-Mn1,5%-Sc0,8%-Zr0,4% po procesie kulowania z wykorzystaniem solwera ANSYALS-Dyna. Model obliczeniowy umożliwia symulację zjawisk zachodzących na skutek odkształcenia plastycznego wywołanego uderzeniem stalowej kulki o powierzchnię analizowanego stopu aluminium. Analizie poddano dwa zmienne parametry wejściowe: średnicę oraz prędkość kulki. Parametryzacja warunków brzegowych potwierdziła zależność rozkładu naprężeń ściskających w funkcji średnicy oraz prędkości kulki. Celem pracy było przedstawienie możliwości kreowania właściwości warstwy wierzchniej w aspekcie wartości i rozkładu naprężeń własnych. Wybrane wyniki analizy numerycznej zostały porównane z wynikami eksperymentalnymi. Różnica w wynikach pomiędzy symulacją a eksperymentem wynosi średnio 19,7%.

EN

In this paper, we presented the results of the analysis of the stresses in the Al-Mg5%-Mn1,5%-Sc0,8%-Zr0,4% alloy after shot peening process using solver ANSYS® LS-Dyna. The computational model illustrates the phenomena occurring as a result of plastic deformation caused by hitting a steel ball on the surface of the analyzed aluminium alloy. We analyzed two input variables: diameter and speed of a ball. The resulting normal stress distribution centred exposes the minimum compressive stress at a position located at a depth point of Belayev 0.125 mm with a value of σ = -345 MPa. Variable parameter shows the correlation of the boundary conditions of minimum stress increase with increasing ball’s diameter and its speed. Selected points of numerical analysis were verified with experimental results.

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INFLUENCE OF SINGLE-STAGE AND DUPLEX SHOT PEENING ON SURFACE ROUGHNESS AND RESIDUAL STRESSES IN Al Mg5 Mn1 Sc0,8 Zr0,4 ALLOY

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Sawicki J. , Januszewicz B. , Byczkowska P. , Stegliński M.

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nr 1

4

Modelowanie wpływu obróbki strumieniowo ściernej na umocnienie warstwy wierzchniej

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Byczkowska P. , Sawicki J. , Klimek L. , Lipa S.

Mechanik

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2015

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tom R. 88, nr 8-9CD1

63--67

PL

Niniejsza praca przedstawia numeryczny model obróbki strumieniowo - ściernej oraz wpływ jaki wywiera ścierniwo wyrzucane przy pomocy strumienia sprężonego powietrza w kierunku oczyszczanej a zarazem modyfikowanej powierzchni. Analizę numeryczną przeprowadzono dla procesu obróbki elektrokorundem uwzględniając takie parametry jak: kąt nachylenia strumienia ścierniwa, odległość dyszy od powierzchni, granulacja ścierniwa. Przeprowadzona symulacja komputerowa pozwoliła na analizę rozkładu odkształceń, naprężeń oraz głębokość ich zasięgu w zależności od parametrów procesu obróbki strumieniowo-ściernej.

EN

This paper presents a method of modeling blast – abrasive treatment and the influence of the abrasive driven by a jet of compressed air on modified surface. Numerical analysis was performed for the corundum treatment process and took into account parameters such as angle of the abrasive flow, nozzle-surface distance and abrasive size. Conducted computer simulation allowed the analysis of the distribution of deformation, stress and the depth of their coverage, depending on the blast – abrasive treatment parameters.

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An analysis of crystallographic texture and residual stresses of aluminium alloy RSA-501 after selected processes of twist extrusion (TE)

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Byczkowska P. , Sawicki J. , Adamczyk-Cieślak B. , Januszewicz B.

Archives of Materials Science and Engineering

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2022

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tom Vol. 118, nr 1

5--28

EN

Purpose: This study presents the residual stress analysis for the twist extrusion (TE) process after the experiment and numerical simulation and the analysis of the crystallographic texture changes and changes in hardness before and after the TE process for an RSA-501 aluminium alloy (Al; Mg5%; Mn1.5%; Sc0.8%; Zr0.4%). Design/methodology/approach: Crystallographic textures were obtained with the PANAlytical Empyrean X-ray diffractometer. The stresses were measured by applying the X-ray method with the use of using the PROTO iXRD diffractometer. Findings: The use of severe plastic deformation processes in the mass of the material leads to a significant change difference in the stress distribution in the workpiece and a change in texture compared to the reference material. The stress distribution in the sample cross-section and stress values varied and depended on the stage of the twisting process to which the surface was subjected. The highest stress (about 600 MPa) appears at the peaks of the front surface when exiting the twist area die TE. Higher stress values at the edges of the specimen are caused by friction (deformation) of the material against the die surface. The TE process strengthened – the highest crystallographic texture background level was 49%. Practical implications: The conducted tests and the obtained results allow the determination of the process parameters and critical areas of the sample by carrying out a numerical simulation. Originality/value: Microhardness increases due to the TE process and the largest values were observed at the edges. This phenomenon is confirmed by the numerical simulation results presented in this paper.

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Numeryczna analiza wpływu rodzaju śrutu na właściwości technologicznej warstwy wierzchniej poddanej procesowi kulowania

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Byczkowska P. , Sawicki J. , Stegliński M.

Inżynieria Materiałowa

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2014

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tom Vol. 35, nr 6

459--463

PL

stanowiącej około 1/3 gęstości stali oraz dość dużej wytrzymałości względnej Właściwości wytrzymałościowe, a co za tym idzie i zastosowanie tych stopów można zwiększyć przez modyfikację warstwy wierzchniej, np. przez proces kulowania. Dobór właściwych parametrów procesu wymaga jednak dużej liczby prób badawczych. Ograniczenie liczby eksperymentów można uzyskać przez wykorzystanie symulacji komputerowych. W efekcie pozwala to na obniżenie kosztów produkcji wraz z poprawą właściwości wytrzymałościowych elementów. Praca dotyczy analizy numerycznej procesu kulowania próbek aluminiowych. Do przeprowadzenia modelowania komputerowego szybkozmiennych i dynamicznych zjawisk wykorzystano oprogramowanie ANSYS Ls-Dyna. W pracy przeanalizowano wpływ zmiany rodzaju śrutu (m.in. wielkość, materiał śrutu) na właściwości warstwy wierzchniej w strefie kontaktu śrutu z powierzchnią obrabianego elementu. Przeprowadzenie symulacji komputerowej pozwoliło na analizę rozkładu odkształceń, naprężeń oraz głębokość ich zasięgu. Wykazano zależność (tendencję), że wraz ze zwiększeniem średnicy śrutu następuje wzrost odkształcenia, natomiast wraz ze wzrostem gęstości pokrycia śrutem powierzchni obrabianej następuje zwiększenie wartości odkształcenia materiału obrabianego.

EN

Aluminum alloys are a structural material because of their low density, representing about 1/3 steel density, and a relatively high specyfic strength. However, their properties and the application can be increased by modifying the surface layer by, for instance, shot peening process. Selecting the proper process parameters requires a large amount of research trials. Limiting the number of experimental plastic treatments processes can be obtained through the use of computer simulations. As a result, it will allow to reduce production costs with increased strength properties of the components. This work concerns the numerical analysis of the shot peening process on aluminum samples. To carry out computer modelling of fast and dynamic phenomena ANSYS Ls-Dyna software was used. The study analyzes the effect of changes in the type of shot (including size, shot material) on the properties of the surface layer in the shot contact zone from the machined surface. Carrying out computer simulation allowed the analysis of the distribution of deformation, stress and the depth of their coverage. It was shown that with increasing shot diameter the deformation is increasing, whereas with higher shot coverage density of treated surface the deformation is increasing.

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Numerical Analysis of Twist Extrusion Pressing of Al-Mg-Mn-Sc-Zr Scalmalloy

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Sawicki J. , Świniarski J. , Stegliński M. , Byczkowska P.

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nr 3

8

Influence of Single-Stage and Duplex Shot Peening on Surface Roughness and Residual Stresses in Al Mg5 Mn1 Sc0,8 Zr0,4 Alloy

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Byczkowska P. , Sawicki J. , Januszewicz B. , Stegliński M.

Archives of Metallurgy and Materials

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2018

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tom Vol. 63, iss. 1

505--511

EN

Conventional shot peening (SP) is cheap surface treatment widely used to enhance fatigue life of mechanical components [3,4]. Basically, it is shooting small particles (shots) on the surface of the sample. However, the process itself is so complex that a lot of companies are not able to optimally employ it due to the amount of parameters that must be controlled all at the same time. The duplex process consists in two stages of shot-peening treatment. The first one consist of shot-peening with spherical cast steel shots or cut wire shots. During the second stage the samples processed in stage one were subject to shot-peening with glass beads. In this work, RSA-501 aluminium alloy was shot peened using shots of different material and diameter and tested using a measurement of residual stresses and surface roughness. Tests and studies conducted so far on RSA-501 aluminium alloy demonstrate that bombardment by a treatment medium in the form of glass beads or shots of various shapes and diameters induces permanent plastic deformation of the surface layer. The roughness achieved after the shot-peening process was determined for each treatment medium. The largest value of Ra parameter was achieved for cut wire shots and this result is consistent with the above-mentioned theoretical knowledge. This medium is the most aggressive one to the surface being treated primarily due to the sharp edges of shots. The duplex process was successful in obtaining higher values of compressive stresses in surface layer than values achievable in conventional single-stage shot peening process.

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The impact of nozzle configuration on the heat transfer coefficient

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Krupanek K. , Staszczyk A. , Sawicki J. , Byczkowska P.

Archives of Materials Science and Engineering

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2018

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tom Vol. 90, nr 1

16--24

EN

Purpose: The purpose of this paper is to elaborate guidelines regarding geometric configurations of a nozzle manifold that have an impact on the effectiveness of the quenching process and occurrence of quenching distortions. Design/methodology/approach: Within the framework of this study there an optimisation of nozzle manifold geometry was carried out with the help of numerical simulations created using Ansys CFX software. In the first stage, a simplification of the nozzle-sample system reduced to a two-dimensional simulation was employed to determine the most optimal location of the coolant stream. In the second stage, several arrangements of nozzle manifolds were tested in a three-dimensional simulation. The parameters that were taken into account included the rate of sample cooling, the uniformity of cooling with a sample volume and heat coefficient takeover read from its surface. Findings: The different active/inactive nozzle arrangements within the manifold and the impact of the specific arrangements on the uniformity of heat transfer from the sample surface were compared. Research limitations/implications: The simulations carried out within the framework of this study are one of the elaboration stages of a new flow heat treatment technology. Practical implications: The application of an efficient cooling chamber in flow treatment makes it possible to limit quenching distortions to a minimum. An optimal adjustment of cooling parameters and cooling nozzle configuration to the shape of the element in order to make the cooling uniform translate directly into a reduction in distortions. Avoiding the necessity to reduce distortions after quenching means there is a significant reduction in detail production costs (grinding). Originality/value: The concept of single-piece flow in the heat treatment for the mass industry is developing rapidly and constitutes a fully automated element of a manufacturing line, adjusted for the purposes of being included in the production process automatic control system. It also makes it possible to conduct comprehensive and integration quality supervision and management at the level of an individual element, which is not possible in the case of batch heat treatment, which is a gap in the production process.

10

Analysis of the impact of double shot peening on the value of roughness parameter and distribution of stresses in the RSA 501 alloy

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Byczkowska P. , Sawicki J. , Januszewicz B. , Stegliński M.

Advances in Science and Technology. Research Journal

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2017

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tom Vol. 11, no 3

1--9

EN

The bead blasting process is widespread in both the automotive and aerospace industry and is performed in order to improve the fatigue strength of various components. Bead blasting is a cold plastic forming process during which the surface of the material processed is hit by small, hard particles consisting of steel pellets, bearing balls or glass beads. It increases the hardness of the outer layer and establishes compression stresses inside it, which is why this processing is often used to improve fatigue strength. Contrary to other peening methods, bead blasting does not result in a reduction in the height of the processed surface’s unevenness in most cases. Shot peening changes the residual tensile stresses into residual compression stresses, thanks to which, the lifetime of the parts processed is extended and their carrying capacity is increased. The double shot peening process proposed by the authors consists in a two-stage bead blasting process. The first stage consists in blasting with round cast steel pellets, pellets cut from wire or cast iron pellets. During the second stage the same samples underwent glass bead blasting. The tests conducted on the RSA-501 aluminum alloy indicate that as a result of the processing medium’s impact in the form of glass beads or pellets of different diameter and shape, a permanent plastic deformation of the material surface occurs. On the basis of the obtained results it is possible to infer that the choice of parameters of both conventional shot peening and the double shot peening determine the impact thereof on the material’s mechanical properties. Thanks to the application of the double shot peening process there is a noticeable decrease in value of the Ra parameter, by about 40% on average. When analyzing the compressive stress results it is possible to state that after the first blasting process the value of stress was increasing when moving deeply into the sample from its surface, while after the glass bead blasting the value of compressive stress was significantly higher already near the surface. Double shot peening results in an increase in the value of compressive stresses by 40-50% when compared to conventional blasting.

11

Numerical Analysis of Twist Extrusion Pressing of Al-Mg-Mn-Sc-Zr Scalmalloy

100%

Sawicki J. , Świniarski J. , Stegliński M. , Byczkowska P.

Archives of Metallurgy and Materials

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2018

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tom Vol. 63, iss. 3

1385--1392

EN

Twist extrusion is a processing method involving the extrusion of a sample with a prismatic cross-section using a tool composed of four prismatic parts bisected by a screw component. A beneficial change in mechanical durability is one of the main factors enabling the use of highly durable Al-Mg-Mn-Sc-Zr alloys to construct functional components of non-stationary robots. As part of the present research, ANSYS® software was used to simulate a twist extrusion process. An analysis of a sample entering and passing through the entire twisting area was performed, up to the point of full twisting of the base of the sample. The stress conditions in the sample were analysed as it passed through the twisting area. The highest stress values (reaching up to 600 MPa) were detected at the tips of the sample face as the sample exited the twisting area. The lowest stress values, at around 170 MPa, were detected at the side edges of the sample.

12

The influence of quenching temperature on distortions during the individual quenching method

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Wołowiec-Korecka E. , Stachurski W. , Zgórniak P. , Korecki M. , Brewka A. , Byczkowska P.

Archives of Materials Science and Engineering

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2020

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tom Vol. 105, nr 2

80--85

EN

Purpose: In this paper, the impact of hardening temperature on the quenching distortions which occur during low-pressure carburizing with gas quenching - using the individual quenching method - was analysed. Design/methodology/approach: The reference elements were subjected to carburizing at 980°C, followed by gas quenching at temperatures of 860°C, 920°C and 980°C. The geometrical measurements of the elements were made before and after the chemical treatment and the size of the quenching distortions of their geometrical parameters was determined. Findings: It was demonstrated that a high temperature of quenching has an unfavourable effect on changes in cylindricity and roundness parameters but, at the same time, reduces the size of distortion of outer parameters. Low temperature quenching reduces quenching distortions of cylindricity and roundness parameters while increasing the distortion of outer dimensions. Research limitations/implications: Based on the research and analysis carried out in this work, it was found that the use of lower quenching temperature is justified in economic and quality terms. Practical implications: In the case of the aviation or automotive industry, very high quality of manufactured elements along with a simultaneous reduction of their production costs is extremely important. Maintaining the dimensions of the elements during heat treatment is extremely difficult. The tests allowed to determine the optimal hardening temperature, which brings with it acceptable deformations. Since it is easier to “repair” the outer geometrical dimensions (diameter, thickness), it seems that quenching from lower temperatures is a more favourable process. Originality/value: The conducted tests allowed to determine the most favourable conditions for hardening elements from the automotive industry, taking into account the occurring deformations and their subsequent processing

13

Synergy of the Plastic Treatment HPT and Shot Peening in Aluminium Alloy Al-Mg-Mn-Sc-Zr

75%

Stegliński M. , Byczkowska P. , Sawicki J. , Kaczmarek Ł. , Januszewicz B. , Klich M.

Archives of Metallurgy and Materials

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2016

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tom Vol. 61, iss. 2B

1135--1142

EN

An improvement in fatigue strength is one of the main factors enabling the use of high-durability Al-Mg-Mn-Sc-Zr alloys in functional components of mobile robots. As part of this study, a computer simulation was carried out using ANSYS LS-DYNA software that involved the hybridization of high pressure torsion (HPT) and shot peening (SP) forming processes. The numerical analysis was aimed at determining residual stresses and strains that affect the durability and stress characteristics of the analyzed Al alloy. Results of the study indicate that tensile stresses of σ = 300 MPa generated as a result of HPT are transformed into a beneficial stress of σ = 25 MPa resulting from plastic strains caused by SP surface treatment.