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1

Wykorzystanie obróbki plastycznej we współczesnych procesach wytwórczych

Styp-Rekowski Michał, Matuszewski Maciej, Polishchuk Oleg

Obróbka Metalu

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2023

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nr 2

52--57

PL

W artykule wskazano cechy obróbki plastycznej, które powodują, że ta technika obróbki jest szeroko stosowana we współczesnych procesach produkcyjnych. Ukazano także możliwości wspomagania tego rodzaju obróbki innymi technikami, np. laserem, w wyniki czego realizowane procesy nabierają charakteru hybrydowego. Zaprezentowano maszyny, narzędzia i procesy technologiczne, które powodują takie duże zainteresowanie tą techniką ze strony przemysłu.

EN

In this paper the features of plastic forming that make this processing technique widely used in modern production processes were described . The possibilities of supporting this type of processing with other techniques, e. g. laser, were also shown. The reason for this is that the implemented processes becoming a hybrid character. Machines, tools and technological processes that cause such great interest in this technology from the industry were presented.

2

Micro-forming of Al-Si foil

Haga T., Inoue K., Watari H.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 40, nr 2

115-122

EN

Purpose: of this paper is as below. The investigation of the ability of the cold micro-forming of non-metallic glass was purpose. The grain of the rapidly solidified aluminium alloy became fine. The aluminium alloy foil with fine grain was used, and the investigation of the micro-formability of this alloy was investigated. Moreover, increase of the forming speed was investigated. The increase of the forming speed was purpose of this study, too. Design/methodology/approach: The nozzle pressing melt spinning method was used to attain the rapid solidification of the non-metallic grass. The Al-14mass%Si, which is hyper eutectic but is close to eutectic, was used. The roll contact surface was formed by V-groove. The cold rolling was adopted for forming. The V-groove was machined at the roll surface. The micro-forming was operated at the cold work. Findings: Micro-forming of the crystal aluminium alloy was able by the cold work. The forming speed was 0.04S to form 10 ěm height. The forming speed could be drastically increased. Research limitations/implications: The angle of the V-groove, which was used in the present study, was only 60 degrees. The effect of the groove angle on the protrusion-height was not clear. The used material was only the Al-14mass%Si. Relationship between the material and protrusion-height was not clear. Practical implications: The die for the micro-forming of the resin could be made from economy material by the conventional cold rolling process at short time. Therefore, the mass production of the economy die for resin may be obtained. Originality/value: The micro-forming of the rapidly solidified non-metallic glass by cold work was original.

3

A method for setting variables in Super Plastic Forming process

Cappetti N., Garofalo L., Naddeo A., Nastasia M., Pellegrino A.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 38, nr 2

187-194

EN

Purpose: Superplastic forming (SPF) technology exceeds the limit of standard presswork either of form or of thickness distribution, but the lead time and the energy expenditure are more onerous for industrial use. The aim of this work is to study the role that process parameters play in a superplastic forming manufacturing in order to minimize the processing times and the cost respecting the “total quality” of the finished product. Design/methodology/approach: Identified the basic parameters of SPF process that is the thickness of blank, the strain rate and the processing temperature, were chosen three different values for each of them. For each combination of parameters and using finite element software, a forming simulation of a sample part was made. Important parameters as thickness reduction, stress distribution, time/working pressure curve are calculated and evaluated. Findings: The obtained results were manipulated in order to create some global indicators that was analysed to study the reliance on process quality and production costs. Research limitations/implications: The other and more difficult to define parameters, such as cast and initial sheet shape, friction between cast and sheet, need to be evacuated because they also affect the optimisation process, as well as its affordability, that is the result of careful control of process variables. Practical implications: The highlighted dependencies are whatever useful, during process configuration, to drive production choices for quality improvement and cost reduction of superplastic formed components. Originality/value: The interesting result is that some dependencies are not as strong as expected from literature. As an example, the quality parameters dependence on the strain rate is no linear. So much as to the decrease of strain rate some indices worsen considerably.

4

The role of quality control operations in a process of plastic forming

Topolska S.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 23, nr 2

95-98

EN

Purpose: The aim of this paper is present the role of quality control operations in such a complex manufacturing process like plastic forming. Nowadays classical manufacturing process management is replaced with total quality management philosophy. Design/methodology/approach: The presented results base on the investigations conducted in manufacturing plants of heavy industry. Next the results of researches have been compared with requirements of quality standards. Findings: Results obtained in the work point the importance of a system of continuous quality monitoring and of quality control operations. Moreover the improvement in quality management is directly related with the corporate image. Research limitations/implications: The presented results base on the analysis of manufacturing processes of steel mills and are considered with the process of plastic forming and related processes. It must be stated that some technological parameters are confidential. Practical implications: The practical implication of the work is considered with the proposal of a scheme of quality control operations in a manufacturing process of plastic forming. This scheme could be used as a remark showing the proper manufacturing process planning. Originality/value: The work presents the analysis of manufacturing processes for heavy industry according the quality assessment what is rather a lateral problem in quality analysis.

5

The influence of thermo-mechanical processing on deformability and structural changes of duplex steel

Radwański K., Niewielski G., Kuc D.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 20, nr 1-2

175-178

EN

Purpose: In conventional hot deformation methods of duplex steels, low values of boundary strain are obtained, resulting from the disparate behaviour of ferrite and austenite. This paper analyses the capacity for enhancing deformability of two-phase ferritic-austenitic steels of the "duplex" type via thermo mechanical processing. Design/methodology/approach: Steel specimens were subjected to cold deformation with a 70% rolling reduction. After a hot solution treatment beginning at 1350 degrees centigrade, the specimens were tensioned in the "Instron" strength-testing machine in temperatures ranging from 800 to 950 degrees centigrade at a rate of vr=15x10-3/3x10-1 mm/s in a 0.005 Pa vacuum. Structural examination was carried out using light and electron microscopy. A quantitative analysis of structural changes was performed using the "MetIIo" image analysis programme. Findings: The process parameters at which the investigated steel shows the superplastic flow effect have been determined. Practical implications: The capacity for increased deformability through combined thermo-mechanical processes, requiring a precise selection of the deformation parameters, has been indicated. Originality/value: The results obtained are vital for designing an effective thermo-mechanical processing technology for the investigated steel.

6

Research activities of computer-aided materials processing laboratory

Im Y. T., Lee H. W., Lee H. C., Awais M., Jin Y. G., Jung K. H., Jung K. H.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 24, nr 1

219-229

EN

Purpose: of this paper is to review the research works carried out at the national research laboratory for computer-aided materials processing at the department of mechanical engineering at KAIST. Design/methodology/approach: The research papers published so far from the laboratory were carefully reviewed and highlights for developing simulation tools for mesh generation, 2D or 3D finite element analyses for forging, shape rolling, solidification, semi-solid forging, compression molding of thermoset composites, injection molding without or with short fibers, and expert system for multi-stage axi-symmetric cold forging, extrusion, and multi-pass shape rolling are recaptured. Findings: According to this survey, the important issues involved with program developments and their industrial applications were revisited. Research limitations/implications: Understanding of material behaviour at various processing conditions and characterization of proper boundary conditions in terms of friction and temperature should be carefully made. Handling of complex geometry and computational efficiency for such geometry should be improved as well. Further development of three dimensional design systems should be necessary. Practical implications: Proper usage of the simulation tools and interface such tools with the automatic design system with the help of artificial intelligence will be very useful at the design stage of new manufacturing products and processes. In addition, proper understanding of deformation mechanics is of importance to properly utilize such numerical tools. Originality/value: Various aspects of limitations involved with program developments and their usage are identified and some important industrial applications demonstrated.

7

Forging and rolling of magnesium alloy AZ61

Greger M., Kocich R., Čižek L.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 20, nr 1-2

447-450

EN

Purpose: The paper summarises results of experiments aimed at development of structure of modified alloy AZ61 at hot deformation. Design/methodology/approach: Deformation behaviour of alloy was verified at the temperature of 420 degrees centigrade by rolling at 380 degrees centigrade by forging, respectively. Findings: Magnesium alloy AZ 61 have hexagonal structure and their forming is at room temperatures very difficult, that's why big plastic deformations are carried out in hot condition. After plastic deformations was obtained that original grain size decreased 15 times. Research limitations/implications: This paper provide data about magnitude of deformation, strain rate and temperature of forming at different techniques of plastic deformation. It was aimed to determine the conditions for non problem rolling and forging respectively. Practical implications: Initial structure was as cast and after heat treatment T4. Heat treatment appeared much better for forming as well as forging than rolling because of state of stress. Originality/value: Role of beta phase (Mg17Al12) in these alloys at plastic forming is very important, such that how it was obtained, best final properties of AZ 61 alloy supports very fine particles, distributed into Mg matrix. Next a relevant information is that multi stage forming process is much better in comparison with a big single reduction.

8

The physical modelling of a normalising rolling of plates of S460NL1 steel grade

Knapiński M., Markowski J.

Archives of Materials Science and Engineering

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2007

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Vol. 28, nr 6

373-376

EN

Purpose: The aim of the present work was to demonstrate that, in laboratory conditions and using a physical simulator of metallurgical processes, it us possible to reflect the actual production process and, at the same time, to simulate new, not necessarily perfect rolling technologies, while not incurring any outlays on industrial lots of a new product line. Design/methodology/approach: The article present the results of physical simulations of the process of rolling plates of steel S460NL1 on the finishing stand of a reversing mill. The simulations were performed for three final plate thicknesses, namely 8, 10 and 12 mm. Findings: The purpose of the simulations was to select the conditions of band deformation with the aim of obtaining, directly after rolling, a material structure corresponding to the structure obtained from normalizing annealing. Thus, the simulations reflected the normalizing rolling process. Practical implications: The researches carried out has allowed to elaborate new technology of production of rolling plate without a additional thermal treatment like as normalisation. It allow to decrease a time and total cost of production for this sort of product. Originality/value: The investigation carried out has confirmed that it is possible to obtain and manufacture 8, 10 and 12 mm-thick plates of S460NL1 grade steel by normalizing rolling in the conditions of the plant under consideration.

9

The TEM study of structure of 1H18N9T stainless steel buildups

Presz W., Kaczorowski M.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 17, nr 1-2

393--396

EN

Purpose: The reason of investigation was finding the answer of the question what was the reason of extreme hardness of build-ups created during bulk metal forming processes of austenitic stainless steel. Design/methodology/approach: The studies were conducted using transmission electron microscopy (TEM). Since very specific specimens special method for thin foil preparation were elaborated. Thin foil method was chose because it was only one which supply both structure and diffraction information. Findings: On the basis of careful analysis structural and electron diffraction pattern it was proposed that simultaneously to very well known strengthening mechanisms like grain refinement and dislocation density increase, the additional mechanism can not be excluded. Based mostly on the electron diffraction pattern (appearance of forbidden reflexes for FCC) it is proposed that this additional mechanism could be the marthensitic transformation caused by very high plastic deformation. Practical implications: At this moment it is difficult to point out the practical implications of the result however the mechanism proposed in this elaboration might be used in design of high strength materials. Originality/value: The main achievement of this investigation is TEM results which analysis allow to propose that an extra-mechanism for strengthening of 1H18N9 stainless steel is marthensitic transformation involved with high plastic deformation in build-ups. Additionally the special method of thin foils preparation was elaborated.

10

Research of upsetting ratio in forming processes on a three - slides forging press

Weroński W. S., Gontarz A., Pater Z.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 17, nr 1-2

409--412

EN

Purpose: The purpose of the presented in this work research was determining the limiting conditions of upsetting in three-slide forging press (TSFP). The free upsetting process and upsetting process in cylindrical impression were analyzed. Design/methodology/approach: The assumed purpose was confirmed in experimental research. For the case of upsetting in cylindrical impression, the research of limiting upsetting coefficients were made for different diameters and impression lengths. Findings: The obtained results showed large variety of limiting upsetting ratio depending on the analyzed impression geometrical parameters. It was stated, that there are 3 phenomena limiting the upsetting process in the die. The main phenomenon is the bar upsetting outside the impression. The upsetting processes in the impression are limited also by bar buckling outside the impression and overlapping inside the impression. Research limitations/implications: The results of research allowed for stating that, besides the process geometrical parameters, friction conditions and type of the formed material influenced the limiting upsetting coefficients in the cylindrical impression. It is purposeful to make the further research determining quantitative and qualitative dependencies between these factors. Practical implications: The obtained results are the basis for designing of forming processes in TSFP in which the upsetting dominates. Especially it considers the elongated forgings and elongated preforms with thickenings. Originality/value: The influence of the impression geometrical parameters on the limiting upsetting coefficients for the case of upsetting in cylindrical impression in TSFP has been analyzed in details. The dependencies, which should be used during designing of upsetting processes in TSFP were determined.

11

Optimization of the blank holder force in cup drawing

Gharib H., Wifi A. S., Younan M., Nassef A.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 18, nr 1-2

291--294

EN

Purpose: Develop an optimization strategy for the cup drawing process in order to produce a defect free deep drawn cup. Design/methodology/approach: An optimization strategy for the blank holder force (BHF) scheme is proposed which searches for the BHF scheme that minimizes the maximum punch force and avoids process limits. This strategy is applied to the linearly varying BHF scheme and compared to the constant BHF. Findings: The optimized linear BHF scheme resulted in an improved cup forming when compared to that produced by the constant BHF scheme. The BHF scheme is optimized for different cases of drawing ratios and die coefficients of friction in order to analyze the nature of the optimum linear BHF scheme. It was found that the slope of the linear BHF scheme increases with the increase in the drawing ratio in a linear manner. Also, the intercept of the function showed a nearly linear variation with the drawing ratio. A general equation is deduced for the optimum blank holder force at any drawing ratio for the cup under study. Research limitations/implications: The proposed optimization strategy can be applied to BHF schemes other than the linear one, and with different objectives. In this scheme, the objective has been the minimization of the maximum punch load. Other objectives like minimum punch work may be implemented. Practical implications: The proposed optimization strategy can be applied to any deep drawn part if an analytical or numerical model is available for this part. Originality/value: The research presented in this paper offers a new optimization strategy which can be useful in controlling the process parameters to produce a defect free deep drawn part using optimum process conditions.

12

Optimization of extrusion force prediction model using different techniques

Jurkovic Z., Jurkovic M., Buljan S.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 17, nr 1-2

353--356

EN

Purpose: This research is determination of the optimal cold forward extrusion parameters with objective the minimization of tool load. Design/methodology/approach: This paper deals with the different optimization approaches relating to determine optimal values of logarithmic strain, die angle and coefficient of friction with the purpose to find minimal tool loading obtained by cold forward extrusion process. To achieve this, it has been carried out two experimental plans based on factorial design of experiment and orthogonal array. By using these plans it was performed classical optimization, according to response model of extrusion forming force, and the Taguchi approach, respectively. Findings: Experimental verification of optimal forming parameters with their influences on the forming forces was done. The experimental results showed an improvement in minimization of tool loading. It was compared results of optimal forming parameters obtained with different optimization approaches and based on that the analysis of the characteristics (features and limitations) of both techniques. Research limitations/implications: Suggestion for future research it will be application of evolutionary algorithms namely model prediction of the process by genetic programming and optimization of extrusion parameters by genetic algorithm. Practical implications: a practical (industrial) implication on the smallest energy consumption, longer tool life, better formability of the work material and the quality of the finished product. Originality/value: This paper is obtained original extrusion force model for experimental domain of forming parameters and identification of parameters influence in that model

13

Multiaspect analyzes of blow moulding process

Szczepański K., Kwiatkowski D., Koszkul J.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 17, nr 1-2

157--160

EN

Purpose: The main purpose of the performed investigations was a multi-aspect analyzes of the blow moulding process in a mould which takes two-stage nature of the process and the occurrence of uncontrolled phenomena which influence the shape, size and quality of the products into consideration. Design/methodology/approach: The value for the Barus number for different dimensions of the nozzle gap and the distribution of the temperature field during blow moulding process have been determined; the product thickness profile has been defined; phenomena which occur during blowing stage have been registered. The investigations have been performed by means of the blow moulding machine of UFP-05 type by IPTS – Metalchem Toruń using the designed and prepared blow mould with the sight-glass made of polycarbonate. Findings: The performed investigations enabled the insight study of uncontrolled phenomena which occur during each individual stage of the process and they showed the dependencies between these phenomena and the process parameters. Moreover, the detailed analyses enabled to determine the influence of these parameters on the physical features and dimensions of the finished goods. Research limitations/implications: The continuation of the investigations with use of extended blow mould design equipped in polycarbonate sight-glass which enabled the determination of the influence of the structure and mould cavity dimensions on the finished product wall thickness seems to be justified. It would be also useful to design the station for the precise non-touch measurements of Barus effect which enabled, except the measurements of the external diameter, the measurements of the finished product wall thickness. Originality/value: The complex analysis of the blow moulding process was possible thanks to innovative and original approach to the experimental tests which enables e.g. the optical registration of the phenomena which occur during blow moulding process.

14

Bending of sheet metal of complicated shapes (for 90° angle and more) in combined tools

Pachole I., Bonifarti S., Ficko M., Vaupotic B., Kovacic S., Balic J.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 16, nr 1-2

88--93

EN

Purpose: Paper describes bending of sheet metal for angles greater than 90 degrees on simple forming tools. Bending using the bending method „traktrix” (in two steps) or the method „turning of the strip” (in one step) can be used for more complicated bends, i. e., for 90 degrees or more. Design/methodology/approach: We used the principle of “traktrix“ curve known in field of deep drawing process in bending process. The bending method, based on „traktrix” curve for more complicated bends, i. e., for 90° or more was developed. A sketch of 90° bending of unknown author and unknown source existed. Findings: It’s possible to bend sheet metal for 90 degrees or more using “traktrix” curve. Research limitations/implications: The research was limited by time and costs. We carried out the research till we get the described product. Future research should be performed in field of parameters of bending tool. Practical implications: We made only one version of each method, of course for practical reasons since we did not need different angles on one product. It would be appropriate to complement both methods in detail theoretically and by testing in the frame of a more comprehensive research work. Originality/value: This article describes the original approach to bending of sheet metal for angles greater than 90 degrees. Movement of forming tool is carried out only in vertical direction and therefore savings by construction and manufacturing of bending tools are possible.

15

An analytical incremental model for the analysis of the cup drawing

Gharib H., Wifi A. S., Younan M., Nassef A.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 17, nr 1-2

245--248

EN

Purpose: of this paper Develop an analytical model for the cup drawing process to solve for the induced stresses and strains over the deforming sheet at any stage of deformation until a full cup is formed. Design/methodology/approach: An analytical model is developed for the cup drawing process by determining the variation of stresses and strains over the deforming sheet. The model uses finite difference approach and numerical procedures to solve for equilibrium, continuity, and plasticity equations in an incremental fashion. Findings: The developed analytical model results showed good correlation with experimental ones from the literature. Also, the analytical model was found to be useful in conducting parametric studies in order to determine how the different process parameters can affect the deforming cup. Research limitations/implications: This paper includes the development of an analytical model to analyze the deep drawing of axisymmetric cups. This model is then used as the solution engine for the optimization of the blank holder force for such cups avoiding failure by wrinkling or tearing. This model also gives an insight of the modes of deformation in the deep drawing process. Practical implications: This paper is part of a procedure that leads to the optimization of the blank holder loading scheme. The full procedure as presented in the two parts of the work may be applied in industry to minimize the maximum punch load or the work done during deep drawing process by modifying the blank holder force and at the same time avoid failures by wrinkling or tearing. Originality/value: Developing a predictive/corrective technique for solving the unknown boundaries of the deforming sheet.