Wyniki wyszukiwania - BazTech

1

Towards the digital model of tool lifecycle management in sheet metal forming

Majstorovic Vidosav, Vukadinovic Vojin, Zivkovic Jovan

Journal of Machine Engineering

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2023

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Vol. 23, No. 3

141--166

EN

Sheet metal forming is a critical process in the manufacturing industry, which involves shaping sheet metal into desired configurations and structures. The use of digital tools in the lifecycle management of sheet metal forming tools has become increasingly important to ensure the efficiency and effectiveness of the process. The digital model of tool lifecycle management (TLM) in sheet metal forming provides a complete approach to manage the entire lifecycle of tools used in sheet metal forming. It enables optimization of tool design, simulation of the tooling process, real-time monitoring of tool conditions, and retirement and replacement of tools. This approach improves efficiency, reduces costs, and ensures optimal performance in sheet metal forming. The paper presents an elaborate analysis of the development of TLM models concerning the progress in ICT modelling and its implementation in the field of sheet metal forming. Furthermore, the paper includes an exemplary TLM model for an industrial enterprise.

2

Investigating the Effect of Hybrid Process: MPF/SPIF on the Microstructure and Mechanical Properties of Brass (65-35) Sheet

Bedan Aqeel Sabree, Algodi Samer Jasim, Hussain Emad Ali

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 3

302--308

EN

Metal forming process is one of the most important manufacturing processes that translate the sheet and bulk metal to the final product with simple punch and. Single point incremental forming (SPIF) process is considered as a modern flexible manufacturing techniques that is use a simple tool and non-specific fixture die to complete the forming, this method is used in prototype manufacturing system due to the time consuming during the forming. The advantage of this process is low cost and simple equipment. However, some limitation was founded including poor geometric accuracy, non- uniform thickness distribution, dimple and high forming time. Multi-point forming (MPF) is another modern forming method that is used in industrial applications due to its advantage such as uniform thickness distribution with low forming time consuming. This method used matrix of simple tools to deform the sheet metal to the desired shape. Wrinkle and dimple due to small contact area between tool and blank under high forming force are considered the main limitation of using MPF process. To take the advantages of this processes with reduced the limitations a hybrid forming (HF) process of both MPF and SPIF are used. The experimental work was applied to produce a hemi-spherical product of brass blank using the SPIF, MPF, and HF processes. Satisfactory results are obtained using a hybrid forming process with free of defects products and reduction in production as compared to the SPIF. A high improve in microstructure including refinements in grain size with twins effects. The sample produced with SPIF process showed a high microhardness as compared to the sample produced using MPF process, however, the hybrid MPF and SPIF forming process showed slightly improving in microhardness as comparing to the as received materials, reflecting the microstructure development of the processed samples.

3

Industrial Application of Surface Crack Detection in Sheet Metal Stamping Using Shift-and-Add Speckle Imaging

Świłło Sławomir, Cacko Robert

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 5

220--235

EN

The sheet metal surface crack detection during manufacturing is an essential issue because of both the product quality and process productivity. Development of solutions to eliminate defective products during the metal forming process is crucial for the smooth production and for developing an appropriate tool geometry in the initial phase of the process. Currently, the methods of surface crack detection used in the industry are mostly related to visual inspection. These are methods that require operators of industrial facilities considerable attention and effort to capture emerging discontinuities on the sheet metal surface. Also, this situation results increase in the duration of the specific operations of stamping and significantly reduces productivity. Therefore, an industrial application of a non-contact laser technique that simultaneously provides the results of the speckle imaging is presented. The authors demonstrate a specially designed machine vision system along with experimental tools for the stamping operation. Proposed solution uses the phenomenon of speckle pattern that appears in the image of the investigated sheet surface produced by the laser beam emission. In this method, coherent laser light is emitted to the surface, where a speckle pattern is generated due to scatter reflection from the sheet metal surface and then, shift-and-add technique and image processing is applied. The proposed measurement technique consists, initially, of making a sequence of images of the tested object for the moving surface of the sheet. Secondly, the object's displacement quantity in each image is determined, and the position is corrected. The test object in each image is moved to the starting position, and all images are superimposed. It allows to obtain a high-quality image with visible surface defects. Finally, the dynamically changing speckle pattern intensity is evaluated using Gaussian-of-Laplacian edge detection to investigate a surface crack location due to the surface discontinues and light scattering. This process is recommended for machine vision imaging of distant objects, which works well in industrial conditions as well as online analysis. Also, from the speckle size measurement, an experimental procedure is employed to verify the best condition for vision system resolution.

4

Application of the finite element method to simulate the friction phenomenon in a strip drawing test

Fejkiel Romuald, Goleń Patryk

Advances in Mechanical and Materials Engineering

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2023

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Vol. 40, nr 1

39--46

EN

Friction is an undesirable phenomenon in the flange area of the drawpiece in sheet metal forming processes, causing a deterioration in surface finish and a decrease in the formability limits of the sheet metal. The aim of this work is numerical analysis using the finite element method of the strip drawing test with two rounded countersamples. This test simulates friction conditions in the flange area of the drawpiece. The results of the experimental research on the influence of surface roughness on the value of the friction coefficient of S235 steel samples were used to verify the numerical results. The relation between the real contact area and the mean roughness Ra of the countersamples was determined. The real contact area increases with the increase of the mean roughness Ra. In sheet metal forming processes, the coefficient of friction depends on the real contact area, and its value increases with the increase of the real contact area.

PL

Tarcie jest zjawiskiem niepożądanym w strefie kołnierzowej wytłoczki w procesach kształtowania blach powodującym obniżenie jakości powierzchni wyrobu i zmniejszenie odkształceń granicznych blachy. Celem pracy jest analiza numeryczna metodą elementów skończonych testu przeciągania pasa blachy pomiędzy dwoma zaokrąglonymi przeciwpróbkami. Test ten symuluje warunki tarcia w strefie kołnierza wytłoczki. Do weryfikacji wyników numerycznych wykorzystano wyniki badań eksperymentalnych wpływu chropowatości powierzchni na wartość współczynnika tarcia próbek ze stali S235. Wyznaczono zależności pola rzeczywistej powierzchni kontaktu od parametru chropowatości przeciwpróbek Ra. Rozmiar rzeczywistej powierzchni kontaktu zwiększa się wraz ze zwiększeniem wartości parametru Ra. W procesach kształtowania blach współczynnik tarcia zależy od pola rzeczywistej powierzchni kontaktu, wraz ze wzrostem pola powierzchni styku rośnie jego wartość.

5

Analysis of the lubrication performance of low-carbon steel sheets in the presence of pressurised lubricant

Trzepieciński Tomasz, Luiz Valmir Dias, Szwajka Krzysztof, Szewczyk Marek, Szpunar Marcin

Advances in Materials Science

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2023

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Vol. 23, nr 2(76)

64--76

EN

In sheet metal forming processes, friction increases the force parameters of the forming process and produces a deterioration in the quality of the surface of the components. The basic way to reduce the unfavourable impact of friction is to lubricate the sheet metal surface with commercial oils. This article presents the results of experimental studies and analysis of variance (ANOVA) of the friction of DC01 low-carbon steel sheets using a strip drawing test. For these tests, a special device was built containing countersamples with a flat surface made of 145Cr6 steel covered with a protective AlTiN coating. Lubricants of different viscosities were fed into the contact zone under forced pressure. The effect of contact pressure on the value of the coefficient of friction was also determined. The predicted R² of 0.9227 was in reasonable agreement with the adjusted R² of 0.9411 confirming that the ANOVA model was reliable. It was found that increasing the lubricant pressure had a beneficial effect in reducing the value of the coefficient of friction. The higher the contact pressure, the more effectively the pressurised oil reduced the value of the coefficient of friction.

6

Analysis of the friction mechanisms of DC04 steel sheets in the flat strip drawing test

Szewczyk Marek, Szwajka Krzysztof

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

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2022

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z. 94

51--61

EN

This article presents the use of a specially designed flat strip drawing tester in order to assess the change in surface topography of DC04 steel sheets. The flat strip drawing test simulates friction conditions in the sheet metal-blankholder interface during deep drawing processes. Experimental tests were carried out at various nominal pressures and in dry friction and lubricated conditions. Two widely available gear and engine oils were used in the study. It was found that, in the range of pressures investigated between 3 and 12 MPa, 80W-90 gear oil provided a greater reduction in the value of the coefficient of friction (COF) than 5W-30 engine oil. Gear oil reduced the COF by an average of about 13.4 [%]. The lubrication efficiency depends on the pressure values; the greater the pressure, the lower the lubrication efficiency. A lowering of the value of the main amplitude surface roughness parameters Sa and Sq was generally observed. SEM analysis showed that even under lubrication conditions there was intense flattening of the roughness asperities of the sheet metal.

PL

W artykule przedstawiono wyniki oceny zmian topografii powierzchni blach stalowych DC04 za pomocą specjalnie zaprojektowanego testera do realizacji testu przeciągania pasa blachy. Test ten symuluje warunki tarcia na styku blachy z dociskaczem w procesach głębokiego wytłaczania. Badania eksperymentalne przeprowadzono przy różnych naciskach nominalnych oraz w warunkach tarcia suchego i smarowania. Do badań wykorzystano dwa powszechnie dostępne oleje przekładniowe i silnikowe. W zakresie analizowanych nacisków 3-12 [MPa], olej przekładniowy SAE80W-90 zapewnił większe obniżenie wartości współczynnika tarcia w porównaniu do oleju silnikowego SAE5W-30. Olej przekładniowy zredukował wartość współczynnika tarcia średnio o około 13.4 [%]. Efektywność smarowania zależy od wartości nacisków. Im większy nacisk tym efektywność smarowania była mniejsza. Zauważono zmniejszenie wartości głównych parametrów amplitudowych chropowatości powierzchni Sa oraz Sq. Na podstawie mikrofotografii SEM zaobserwowano, że nawet w warunkach smarowania dochodziło do intensywnego wyrównywania wierzchołków nierówności blachy.

7

Application of laser barcode technology to sheet metal parts identification

Morawiński Łukasz, Świłło Sławomir, Kocańda Andrzej

Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska

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2022

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z. 162

501--516

EN

Purpose: In the development of ideas for Industry 4.0, information about the element production cycle has become more and more important. Knowledge of the subsequent forming processes, determination of the machine on which the process has been carried out and of the type and wear of the tool, leads to smart production management, which plays an increasingly important role in the metal forming industry. To meet the current expectations for these challenges, an advanced technology needs to be introduced for monitoring the manufacturing processes by deploying flexible solutions. This technology must include, but not be limited to, identifying and tracking the product using laser marking. Design/methodology/approach: Laser marking allows a permanent mark in the form of a barcode to be applied to the sheet metal surface. Commonly used marking methods and the condition of the sheet metal surface can affect the marking contrast. This paper presents a concept for recording individual stages of sheet metal forming and determination of the impact of the laser marking technology on the contrast of the applied barcode. To ensure accurate control of the deformation stages, the bulging process of the spherical dome has been used as an example. Findings: Analysis of the influence of laser marking method on the barcode recognition accuracy can contribute to the development of smart management of the production process according to the idea of Industry 4.0. Research limitations/implications: A large plastic deformation has been applied to the sheet metal surface and no limitation in a barcode reading process (using vision scanning technology) was indicated. Also, the geometry deformation (different angle view of the CCD camera) of the barcode image has introduced no additional problems with a barcode reading. Originality/value: The optimal parameters of a laser marking technique for barcode marking, which are critical for the material that is subjected to metal forming operations that deform it, have been studied. The results shows that traceability is an attractive solution for tracking technological data in the production chain for a single-shaped product.

8

Assessment of frictional performance of deep drawing quality steel sheets used in automotive industry

Trzepieciński Tomasz, Kascak Lubos

Technologia i Automatyzacja Montażu

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2022

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nr 1

37--44

EN

This article presents the results of tribological tests of three grades of deep-drawing quality steel sheets used in the automotive industry. The frictional properties of the sheets were anaysed using a strip drawing test. Friction tests were performed under dry friction and lubrication conditions using machine oil L-AN 46. Additionally, friction tests of pre-strained sheets were also carried out. Cylindrical countersamples with different surface roughness were used. Relationship between the surface roughness, pressure force, lubrication conditions and the value of the friction coefficient were evaluated. It was found that increasing the roughness of the countersamples increased the value of the friction coefficient in both friction conditions analysed. The greater the pressure force, the lower efficiency of lubrication. The effectiveness of reducing the value of the friction coefficient ranged from 20-30% and depended on the pressure force, roughness of the countersamples and the degree of specimen pre-straining.

PL

W artykule przedstawiono wyniki badań tribologicznych trzech gatunków blach stalowych głębokotłocznych stosowanych w przemyśle motoryzacyjnym. Do oceny właściwości tarciowych blach wykorzystano test przeciągania pasa blachy. Testy tarcia przeprowadzono w warunkach tarcia suchego i smarowania olejem maszynowym L-AN 46. Dodatkowo przeprowadzono badania tarcia blach poddanych odkształceniu wstępnemu. Zastosowano przeciwpróbki walcowe o różnej chropowatości powierzchni. Pozwoliło to na określenie relacji pomiędzy chropowatością powierzchni, wartością nacisku, warunkami smarowania oraz wartością współczynnika tarcia. Stwierdzono, że zwiększenie chropowatości przeciwpróbek powodowało zwiększenie wartości współczynnika tarcia w obydwu zastosowanych warunkach tarcia. Im większa siła docisku tym efektywność smarowania olejem maszynowym zmniejszała się. Efektywność zmniejszania wartości współczynnika tarcia wahała się w zakresie 20-30% i zależała od siły nacisku, chropowatości przeciwpróbek oraz stopnia wstępnego odkształcenia próbek.

9

Kształtowanie przyrostowe blach – możliwości zastosowania w przemyśle lotniczym

Trzepieciński Tomasz

Stal, Metale & Nowe Technologie

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2022

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nr 3-4

58--63

PL

Kształtowanie materiałów w postaci blach przez wytłaczanie jest jedną z najpopularniejszych metod otrzymywania gotowych wyrobów w warunkach produkcji małoseryjnej. W artykule przedstawiono charakterystykę metod przyrostowego kształtowania blach za pomocą następujących metod: jednopunktowego (ang. Single-Point Incremental Forming) i dwupunktowego tłoczenia przyrostowego (ang. Two-Point Incremental Forming). Przedstawiono również parametry decydujące o możliwości zastosowania danej odmiany SPIF oraz zjawiska ograniczające proces przyrostowego kształtowania blach ze stopów trudno odkształcalnych.

EN

Sheet forming of materials by deep drawing is one of the most popular methods of obtaining finished products in small lot production conditions. This paper presents the characteristics of incremental sheet forming technique using the following methods: Single-Point Incremental Forming (SPIF) and Two-Point Incremental Forming (TPIF). Factors influencing the possibility of the application of a specific SPIF method and phenomena that limit the use of the incremental forming of difficult- -to-form materials are also presented. Moreover, the advantages and disadvantages of incremental sheet forming in the context of its application in the aviation industry are specified.

10

Modelling of the draw bead coefficient of friction in sheet metal forming

Chodoła Łukasz, Ficek Daniel, Szczęsny Ireneusz, Trzepieciński Tomasz, Wałek Łukasz

Technologia i Automatyzacja Montażu

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2021

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nr 3

3--9

PL

W artykule przedstawiono wyniki wyznaczania wartości współczynnika tarcia na progu ciągowym w procesie kształtowania blach. Jako materiał badawczy wykorzystano blachy stalowe, mosiężne i ze stopu aluminium, które zostały wycięte w różnych kierunkach względem kierunku walcowania blachy. Pasy blachy badano w warunkach tarcia suchego oraz smarowania powierzchni blach olejem maszynowym. Wyniki eksperymentów posłużyły do zbadania wpływu parametrów procesu tarcia na wartość współczynnika tarcia za pomocą sztucznych sieci neuronowych. Dane wejściowe zostały zoptymalizowane przy użyciu algorytmu genetycznego, selekcji krokowej postępującej oraz wstecznej. Celem badań było określenie wpływu wartości kary jednostkowej na istotność poszczególnych parametrów wejściowych sieci neuronowej oraz wartość błędu generowanego przez perceptron wielowarstwowy. Stwierdzono, że w przypadku wszystkich materiałów wartość współczynnika tarcia próbek zorientowanych pod kątem 90° była większa niż dla orientacji próbek 0°. Testy tarcia wykazały również, że smarowanie blach zmniejszyło opory tarcia o 12-39% w zależności od gatunku materiału blachy. Spośród wszystkich parametrów wejściowych, które istotnie wpływają na wartość współczynnika tarcia, najważniejsze z nich to warunki smarowania oraz orientacja próbki.

EN

This paper presents the results of determining the value of the coefficient of friction on the drawbead in sheet metal forming. As the research material, steel, brass and aluminium alloy sheets cut at different directions according to the sheet rolling direction were used. Sheet strip specimens were tested under dry friction and lubrication of sheet surfaces using machine oil. Results of experiments were used to study the effect of process parameters on the coefficient of friction using artificial neural networks. Input data was optimized using genetic algorithm, forward stepwise selection and backward stepwise selection. The aim of the research was to determine the effect of the value of the unit penalty on the significance of individual input parameters of the neural network and the value of the error generated by the multilayer perceptron. It was found that in the case of all materials the value of coefficient of friction for specimen orientation 90° was greater than for the specimen orientation 0°. Friction tests also reveal that sheet lubrication reduced the frictional resistance by 12-39%, depending on the grade of sheet material. Among all input parameters that significantly affect the value of the coefficient of friction the most important are the lubrication conditions and the orientation of the sample.

11

Multivariate modelling of effectiveness of lubrication of Ti-6Al-4V titanium alloy sheet using vegetable oil-based lubricants

Trzepieciński Tomasz, Szpunar Marcin

Advances in Materials Science

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2021

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Vol. 21, nr 2(68)

26--39

EN

The article presents the results of modelling the friction phenomenon using artificial neural networks and analysis of variance. The test material was composed of strip specimens made of 0.5-mm-thick alpha-beta Grade 5 (Ti-6Al-4V) titanium alloy sheet. A special tribotester was used in the tests to simulate the friction conditions between the punch and the sheet metal in the sheet metal forming process. A test called the strip drawing test has been conducted in conditions in which the sheet surface is lubricated with six environmentally friendly oils (palm, coconut, olive, sunflower, soybean and linseed). Based on the results of the strip drawing test, a regression model and an artificial neural network model were built to determine the complex interactions between the process parameters and the friction coefficient. A multilayer perceptron with one hidden layer and eight neurons in this layer showed the best fit to the training data. The network training was conducted using three algorithms, i.e. Levenberg-Marquardt, back propagation and quasi-Newton. Taking into consideration both the coefficient of determination R2 (0.962) and S.D. ratio (0.272), the best regression characteristics were presented by the network trained using the Levenberg-Marquardt algorithm. From the response surfaces of the quadratic regression model it was found that an increase in the density of lubricant at a specific pressure causes a reduction in the coefficient of friction. Low density and high kinematic viscosity of the oil leads to a high coefficient of friction.

12

Modelling anisotropic phenomena of friction of deep-drawing quality steel sheets using artificial neural networks

Trzepieciński Tomasz, Lemu Hirpa G., Chodoła Łukasz, Ficek Daniel, Szczęsny Ireneusz

Advances in Materials Science

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2021

|

Vol. 21, nr 3(69)

31--42

EN

This paper presents a method of determining the coefficient of friction in metal forming using multilayer perceptron based on experimental data obtained from the pin-on-disk tribometer. As test material, deep-drawing quality DC01, DC03 and DC05 steel sheets were used. The experimental results show that the coefficient of friction depends on the measured angle from the rolling direction and corresponds to the surface topography. The number of input variables of the artificial neural network was optimized using genetic algorithms. In this process, surface parameters of the sheet, sheet material parameters, friction conditions and pressure force were used as input parameters to train the artificial neural network. Some of the obtained results have pointed out that genetic algorithm can successfully be applied to optimize the training set. The trained multilayer perceptron predicted the value of the friction coefficient for the DC04 sheet. It was found that the tested steel sheet exhibits anisotropic tribological properties. The highest values of the coefficient of friction under dry friction conditions were registered for sheet DC05, which had the lowest value of the yield stress. Prediction results of coefficient of friction by multilayer perceptron were in qualitative and quantitative agreement with the experimental ones.

13

Sheet metal forming using environmentally benign lubricant

Więckowski Wojciech, Adamus Janina, Dyner Marcin

Archives of Civil and Mechanical Engineering

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2020

|

Vol. 20, no. 2

307--319

EN

Sheet metal forming belongs to one of the most important technologies enabling the production durable but quite lightweight metal parts. The quality of the drawn parts depends on the deformed sheet metal, applied forming technology and process parameters, such as contact pressure, relative velocity, temperature or lubrication. The forming of steel (1.4021) parts using benign lubricant is analysed. The paper proposes replacing conventional mineral/synthetic lubricants with ones based on vegetable oils and boric acid. The effectiveness of the lubricants was assessed in laboratory strip drawing and cupping tests, and in production. An oil-based lubricant with an additive of boric acid is very effective in reducing frictional resistance and protecting the forming tools against galling.

14

Kształtowanie przyrostowe blach – możliwości zastosowania w przemyśle lotniczym

Trzepieciński Tomasz

Stal, Metale & Nowe Technologie

|

2019

|

nr 5-6

48--54

PL

Kształtowanie materiałów w postaci blach przez wytłaczanie jest jedną z najpopularniejszych metod otrzymywania gotowych wyrobów w warunkach produkcji małoseryjnej. W artykule przedstawiono charakterystykę metod przyrostowego kształtowania blach za pomocą następujących metod: jednopunktowego (ang. Single-Point Incremental Forming) i dwupunktowego tłoczenia przyrostowego (ang. Two-Point Incremental Forming). Przedstawiono również parametry decydujące o możliwości zastosowania danej odmiany SPIF oraz zjawiska ograniczające proces przyrostowego kształtowania blach ze stopów trudno odkształcalnych.

EN

Sheet forming of materials by deep drawing is one of the most popular methods of obtaining finished products in small lot production conditions. This paper presents the characteristics of incremental sheet forming technique using the following methods: Single-Point Incremental Forming (SPIF) and Two-Point Incremental Forming (TPIF). Factors influencing the possibility of the application of a specific SPIF method and phenomena that limit the use of the incremental forming of difficult- -to-form materials are also presented. Moreover, the advantages and disadvantages of incremental sheet forming in the context of its application in the aviation industry are specified.

15

Possibilities of application of incremental sheet-forming technique in aircraft industry

Trzepieciński T., Krasowski B., Kubit A., Wydrzyński D.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

|

2018

|

z. 90 [298], nr 1

87--100

EN

The article includes the characteristics of incremental forming of the sheet using the following two methods: Single Point Incremental Forming and Two Point Incremental Forming. The factors influencing the possibility of method application and the phenomena that limit the use of incremental forming of the sheet are presented. Based on the conducted experimental test, the disadvantages and advantages of single point incremental forming are specified. Possibilities for the use of the presented incremental forming technique for manufacturing elements in the aircraft industry are also included.

PL

Artykuł zawiera charakterystykę metod kształtowania przyrostowego blach z wykorzystaniem dwóch odmian: kształtowania jedno- i dwupunktowego. Zaprezentowano czynniki wpływające na możliwość zastosowania omawianej metody oraz zjawiska ograniczające zastosowanie kształtowania przyrostowego blach. Na podstawie przeprowadzonych eksperymentalnych badań pilotażowych przedstawiono również wady i zalety jednopunktowego kształtowania przyrostowego. Zawarto również wybrane przykłady zastosowania technik kształtowania przyrostowego do wytwarzania wyrobów dla przemysłu lotniczego.

16

Analiza numeryczna odkształceń blachy DC04 w procesie kształtowania wytłoczek osiowosymetrycznych

Kraska D., Trzepieciński T.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

|

2018

|

z. 90 [298], nr 2

163--174

PL

Artykuł zawiera wyniki symulacji numerycznych metodą elementów skończonych procesu formowania wytłoczek cylindrycznych z wykorzystaniem metody jawnej (explicit) całkowania równań ruchu w warunkach kontaktu z tarciem izotropowym i anizotropowym. Przedstawiono wyniki eksperymentalne oraz numeryczne uzyskane w programie Abaqus 6.14-5. Celem badań eksperymentalnych była analiza płynięcia materiału pod wpływem zadawanych obciążeń. Wyniki te wykorzystano do weryfikacji wyników symulacji numerycznych. Stwierdzono, że chociaż anizotropia oporów tarcia decyduje o wysokości występów na krawędzi wytłoczki, wpływ warunków tarcia na ostateczny kształt wytłoczki i rozkład grubości ścianki jest stosunkowo niewielki w porównaniu z wpływem anizotropii materiałowej. Badania wykazały również, że analiza numeryczna uwzględniająca dyskretyzację blachy za pomocą 3-węzłowych trójkątnych elementów typu shell S3R zapewnia najlepsze przybliżenie wyników symulacyjnych do danych eksperymentalnych, gdy uwzględnia się w modelu numerycznym jednocześnie anizotropię materiałową oraz anizotropię oporów tarcia.

EN

This article presents the results of FEM (finite element method) numerical simulations of forming cylindrical drawpieces using the explicit integration procedure in the presence of contact conditions with isotropic and anisotropic friction. The experimental and numerical results obtained in the Abaqus 6.14-5 program are presented. The aimof the experimental research was to analyse material flow in the forming process. These results were used to verify the results of numerical simulations. It has been found that although frictional resistance anisotropy determines the height of the ears of a drawpiece, the influence of the frictional conditions on the final shape of the drawpiece and wall thickness distribution is relatively small compared to the effect of material anisotropy. The research has also shown that numerical analysis with the workpiece discretised by 3-node triangular shell elements S3R provides the best approximation of simulation results to experimental data in the conditions when numerical anisotropy and anisotropy of frictional resistance are included in the numerical model.

17

Finite element based prediction of deformation in sheet metal forming process

Kraska Damian, Trzepieciński Tomasz

Applied Computer Science

|

2018

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Vol. 14, no 3

43--53

EN

In this paper the sheet forming process of cylindrical drawpieces was sim-ulated based on the finite element method by the explicit approach in the pres-ence of contact conditions with isotropic and anisotropic friction. The ex-perimental and numerical results obtained in the Abaqus finite element (FE) based program are presented. The aim of the experimental study is to analyse material behaviour under deformation and in addition to use the results to verify numerical simulation results. It was found that, although, the anisotropy of resistance to friction affects the height of ears, the influence of the friction formulation is relatively small in comparison with material anisotropy. The study indicates that FE analysis with 3-node triangular shell element S3R elements ensures the best approximation of the numerical results to the real process when both material and friction anisotropy are taken into account.

18

Modelowanie procesu tłoczenia części nadwozia samochodu ze stali superwysoko wytrzymałej

Wyrobek K.

Inżynieria Maszyn

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2017

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R. 22, z. 1

76--84

PL

W artykule przedstawiono model procesu tłoczenia przykładowej części nadwozia samochodu z superwysoko wytrzymałej blachy stalowej typu AHSS (Advanced High-Strength Steels). W tym celu zostały przeprowadzono badania materiałowe stali DP600, na podstawie których wykonano symulacje procesu tłoczenia. Opracowany proces może stanowić ekonomicznie uzasadnioną alternatywę dla kosztownych procesów obróbki plastycznej na gorąco czy hydroformowania.

EN

The article presents process of sample car body part made from advanced high strength steel sheet (AHSS). For this purpose conducted research tensile strength of DP600 steel and based on them simulations of forming process. Developed process may constitute an economically viable alternative to the costly hot forming and hydroforming processes.

19

The Effect of the Use of Technological Lubricants Based on Vegetable Oils on the Process of Titanium Sheet Metal Forming

Więckowski W., Dyja K.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 2A

489--494

EN

The paper evaluates the drawability of titanium sheet metal Grade 2, with the focus on friction conditions that are present in the sheet metal forming process. The study aims to present the results of the examinations of the friction coefficient during a strip drawing test. The focus of the experiment was on lubricants based on vegetable oils i.e. rapeseed oil, sunflower oil and olive oil. Boric acid was used to improve the lubricating properties of vegetable oils. The results of numerical simulations of the process of forming a cover with stiffening components made of grade 2 titanium sheet metal was also presented. The numerical simulation was carried out using the FEM method with PAMStamp 2G software. The effect of conditions of friction between the sheet metal and tool parts and pressure force of the blank holder on the forming process were investigated. Numerical calculations were performed with consideration for the phenomenon of material strain hardening and anisotropy of plastic properties of the sheet metal formed. The analysis of the deformations and reduction in wall thickness of the drawn parts can be used for determination of the effect of changes in selected parameters on the process of drawn part forming. The quality of drawn parts was assessed based on the shape inaccuracy determined during simulation of forming. The inaccuracy depended on the conditions of the process and strength properties of the titanium sheet metal.

20

Analysis of forming thin titanium panels with stiffeners

Adamus J., Winowiecka J., Dyner M.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 1

173--180

EN

The growing demand for light and durable products has caused an increase in interest in products formed of thin sheets. In order to ensure sufficient stiffness of the drawn - parts, stiffening is often performed. Unfortunately, during the forming of stiffeners unwanted deformations of the drawn parts very often appear, which prevent them from further exploitation. In the paper, forming thin titanium panels with stiffeners is analysed. The panels are made of sheets of commercially pure titanium: Grades 2, 3 and 4. In the results of numerical analyses which were performed using PamStamp 2G, taking into consideration the impact of the blank holder force and friction conditions on the strain distribution in the drawn parts, sheet thinning and springback values are presented. The numerical analysis results were compared with the experimental tests. It was concluded that in order to prevent panel deformation being a result of residual stresses, it is necessary to ensure adequate friction conditions on the contact surfaces between the deformed material and tools as well as a suitable blank holder force.