Miklós Tisza

University of Miskolc · Department of Mechanical Technology

The modern vehicles demand a better fuel economy, decrease in ozone harming substance outflows, and superior safety requirements led to new developments of steel grades with higher strength and good formability. Third generation of advanced high strength steels are the next stage for the automotive companies in steel sheets development. The princip...

The modern automobile industry reached a high level of development of steel grades with extraordinary strength and formability, through different new production processes and new processing strategies. The third generation of advanced high strength steel is a new concept that have been developed lately and have already been incorporated in the mode...

The modern automobile industry reached a high level of development of steel grades with extraordinary strength and formability, as a result of the increasing demand for minimizing the fuel economy, decreasing in harming substance outflows, and improve safety precautions. The third generation of advanced high strength steel is a further development...

Ebben a cikkben a klincselt kötések egyszerűsített végeselemes modellezési eljárásának egy lehetséges megoldása kerül bemutatásra. A modellezést anyagvizsgálatok előzték meg, amelyek alapján a modell kalibrációja megtörtént. A modell érzékenységéről röviden szó lesz. Jelen cikk az egyszerű, húzó terhelésnek kitett kötések vizsgálatával foglalkozik,...

Az utóbbi évtizedekben az autóipar folyamatosan növekvő követelményekkel nézett szembe. A növekvő követelmények mind a felhasználók, mind pedig a jogi előírások terén megfigyelhetők. Fogyasztói oldalról az egyre gazdaságosabb, kisebb fogyasztású, ugyanakkor magasabb kényelmi szintet és nagyobb biztonságot adó személygépkocsik iránti igény jelentkez...

Sheet metal forming is one in all the foremost important production processes in car manufacturing; therefore its developments are significantly determined by the demands of the automotive industry. Recent trends in car production are also characterized by applying lightweight principles. Its main priority is to fulfil both the customers’ demands a...

The aluminium alloy studied in this paper is the heat treatable AA7075 which has zinc as the main alloying element. 7xxx aluminium alloys have the best strength performance among all commercial series and AA7075 has tensile strength above 500 MPa. The outstanding strength properties open the possibility to use this alloy in automotive industry as a...

In this paper, some material developments and its demands in sheet metal forming for automotive industry will be overviewed. It is not easy to match and meet good performance, low consumption, low emission and high safety with comfort simultaneously, only by applying conventional materials and processes. Due to these factors and needs, continuous m...

1 www.ombkenet.hu 153. évfolyam, 2-3. szám • 2020 1. Bevezetés Az egyre fokozódó globális verseny miatt az autóiparban a gyártási költségek csökkentése kiemelt célkitűzés. A gyár-tási költségek csökkentése több okból is szorosan kapcso-lódik a járművek tömegének csökkentéséhez. A tömeg-csökkentés a járműgyártásban nemzetközi téren is a kuta-tási te...

Magyarországon a járműipar a kiemelt stratégiai húzóágazatok közé tartozik, magas hozzáadott értékű, a hazai GDP mintegy egytizedét biztosító tudás-intenzív ágazat. A világméretű globális versenyben az autóipari fejlesztéseket számos, gyakran egymásnak is ellentmondó követelmények határozzák meg. Fogyasztói oldalról a gazdaságos üzemeltetés mellett...

In Hungary, the automotive industry is one of the key strategic, knowledge-intensive sectors with high added value, providing one-tenth of the domestic GDP. In global competition, automotive development is driven by a number of often conflicting requirements: from a consumer perspective, in addition to economical operation, the need for greater per...

A cikk a LoCoMaTech H-2020 projekt keretében végzett alakítástechnológiai kutatásokról és az elért eredményekről ad számot. A projekt a Horizon 2020 Európai Uniós program keretében nyert el pályázati támogatást a 2016.09.01-2019.08.31. közötti, 36 hónapos kutatási időszakra. A projekt szakmai feladatait 9 ország 19 intézményéből álló konzorcium val...

A cikkünkben bemutatjuk a klincselés technológiáját és összefoglaljuk a Tanszéken az utóbbi években végzett, klincseléssel kapcsolatos kísérleti és végeselemes szimulációs vizsgálatok eredményét, amelyek egy PhD kutatás részét képezik. Kitérünk a Charpy-féle ütővizsgálatból nyert új eredményeinkre, és néhány fontosabb szimulációs úton nyert követke...

A cikk a Gépészmérnöki és Informatikai Kar alapításának 70. évfordulója alkalmából rendezett Jubileumi Ülés Anyagszerkezettani és Anyagtechnológiai Szekciójában tartott előadás kibővített változata, amely az Anyagszerkezettani és Anyagtechnológiai Intézet jogelődje, a Mechanikai Technológiai Tanszék keretében megvalósult hazai és nemzetközi kutatás...

In this study the effect of the friction coefficient on the clinch joints was examined in experimental and numerical way also. The knowledge of the frictional behaviour during the mechanical joining (i.e. clinching) is important from the point of view of resultant geometry which is related to and influence the strength of the joints, and furthermor...

The automotive industry plays a determinant role in the economy of developed countries. Sheet metal forming is one of the most important processes in car manufacturing. Recent trends in car production may be characterized by the application of lightweight principles. Its main priority is to fulfill both the customers' demands and the increased lega...

In recent year, the e-mobility is undergoing an exponential grow because of CO2 restrictions. Until 2025 it is expected to be between 7-14% of the total market share,, which means that combustion engines have to be more efficient to be competitive. Start-stop and 48V hybridization are rapidly increase market share, to help reaching CO2 legislation...

This study presents the experimental results and the comparison of different analytical models for springback evaluation of bent thin sheets. Three types of advanced high strength steels (from the group of dual phase steels, namely DP600, DP800 and DP1000) and a mild steel (DC04) were used to investigate the sheet profile after rectangular V-die be...

Clinching is a joining technique for similar or dissimilar sheet (metallic or non-metallic) parts that is realized with a mechanical interlock due to local severe plastic deformation. Nowadays it has an ever-growing popularity due to its simplicity and speed. Clinching is suitable to connect dissimilar materials providing a freedom to designers. Li...

This study presents theoretical methods and experimental investigations for prediction on the flange wrinkling of deep drawn cylindrical cups. The prevention of wrinkling in the flange area is most commonly solved by a blank holder. The appropriate suppress of wrinkling is only possible with optimal process parameters, since inadequate blank holder...

In this article the clinched joints were analyzed by finite element method (FEA). The base materials were advanced high strength steels (DP 600, DP 800 and DP 1000). The model validation procedure was done by the DP 600 type of steel sheets; the other two types of steel were only simulated. The goal was to determine the geometrical properties of th...

Due to increasing competition globally among car manufacturing companies cost optimization is one of the major concerns in the automotive industries right from inception stage to the final product delivery along with maintaining its highest quality. Nowadays, rising demand for concept car, automobiles with latest technology, aesthetics of vehicles...

This study is about using of the least squares’ method for parameter defining and model accuracy investigation of mechanical-based work-hardening laws of automotive dual phase steels. The experimental true stress true strain curves were determined by standard, quasi-static tensile tests at room temperature. As most of the commercial finite element...

Car manufacturing has been significantly influenced by sheet metal forming developments, thus the requirements and developments in car manufacturing have decisive role in the development of sheet metal forming, too. The automotive industry is facing challenges of reducing body weight in consideration of environmental problems and higher collision s...

Ebben a cikkben a klincseléssel készített kötések minőségi kérdéseit vizsgáljuk. A gyártás volumene miatt szükséges egyrészt magát a gyártási folyamatot is ellenőrizni, másrészt a kész kötést is. A különböző gyártók által kínált megoldásokat fogjuk röviden áttekinteni 1-1 példán keresztül bemutatva fontosságukat.

Abstract. Forming limit diagrams (FLDs) are generally used to reflect the strain limits of sheet metal materials. These diagrams contain essential information for planning of high series stamping processes, however the experimental definition is still a difficult and time-consuming procedure. Five or more samples are needed to cover the different s...

Clinching is a mechanical cold forming method to join two or more overlapping sheets without using of rivet. This technology is already in use for production of aluminum and steel sheet car body panels. This process is carried out without heat effect on the material structure, thus the clinching is one of the technologies which may replace traditio...

In this paper, we present the possibility of numerical modeling of high strength aluminum alloys gaining an increasing application in the vehicle industry. Our investigations are based on a comparison of real industrial part produced by Hot Forming and Quenching process (HFQ ™) and its numerical modeling results obtained by the AutoForm program. We...

In recent decades, there are many requirements stated against car manufacturing both from the customers' side and also as legal requirements to reduce harmful emissions to provide increased environment protection, as well as to achieve increased safety, higher comfort and more economical vehicles. To meet these often contradictory requirements, app...

The automotive industry has a decisive role in the economy of developed countries. Sheet metal forming – as one of the main processes in car manufacturing – has similarly important role. Concerning the recent trends in car production, the application of lightweight constructions principles is the main priority to meet customers' demands and the inc...

Ebben a cikkben DP600 jelű acélok klincs kötését vizsgáljuk kísérleti és szimulációs úton. A klincs kötés egy bélyeg és matrica szerszámpár segítségével, képlékeny alakváltozások során hozható létre vékonylemezek között. A lemezeket a bélyeg adott erővel a matricába nyomja. Az eljárás gyakorlatilag egy sajtolva lemezalakító technológia, amely a sze...

Forming limit is a complex concept of limit values related to the onset of local necking in the sheet metal. In cold sheet metal forming, major and minor limit strains are influenced by the sheet thickness, strain path (deformation history) as well as material parameters and microstructure. Forming Limit Curves are plotted in ε1 – ε2 coordinate sys...

Purpose: of this paper: The main objectives of this paper are to give an overview about the application of various kinds of high strength steels and aluminium alloys in the automotive industry to produce lightweight car body elements to achieve significant reductions in harmful emissions to provide more environmental friendly vehicles which simulta...

Low cost manufacturing in the automotive industry is one of the main targets due to the ever increasing global competition among car manufacturers all over the World. Sheet metal forming is one of the most important key technologies in the automotive industry; therefore the elaboration of new, innovative low cost manufacturing processes is one of t...

Low cost manufacturing in the automotive industry is one of the main targets due to the ever increasing global competition among car manufacturers all over the World. Sheet metal forming is one of the most important key technologies in the automotive industry; therefore the elaboration of new, innovative low cost manufacturing processes is one of t...

The importance of dual phase (DP) steels in the automotive industry was continuously spreading in the last decade. With their special microstructure—containing ferrite and martensite in particular ratio—high strength and increased formability is available. That’s the reason why the application of DP steels is providing to exceed the 50% in a modern...

The automotive industry always had a determining role in the whole economy. In sheet metal forming both the material and the technological developments are strongly affected by the development tendencies in car manufacturing. One of the main trends in today's car manufacturing is to apply light weight construction principles to meet the increased c...

Abstract Nowadays, mass reduction is the most often used term in the automotive industry. Car manufacturers are continuously working on getting ever lighter models than the previous ones, because of the global competition and the rigorous emission rules. A light car has many advantages: lower consumption, better handling, longer operating distance,...

Aluminium alloys are more and more widely applied in car body manufacturing. Increasing the formability of aluminium alloys are one of the most relevant tasks in todays' research topics. In this paper, the focus will be on the investigation of the formability of aluminium alloys concerning those material grades that are more widely applied in the a...

Car manufacturing is always regarded as the key industry behind sheet metal forming, and thus, the requirements of and developments in car manufacturing play a decisive role in the development of sheet metal forming. The automotive industry is faced with contradictory demands and requirements: better performance with lower consumption and less harm...

Car manufacturing is always the key industry behind sheet metal forming thus the requirements and developments in car manufacturing have decisive role in the development of sheet metal forming, too. The automotive industry faces with very contradictory demands and requirements: better performance with lower consumption and less harmful emissions, m...

Ferritic nitrocarburising is a surface alloying heat treatment, which can provide to components high surface hardness, thus improved wear resistance. In structural steels the porosity of white layer has a key role in wear resistance: the porosity is undesirable. For tool steels the absence of white layer is undesirable. Floe process is one way to d...

Car manufacturing is one of the main target fields of sheet metal forming: thus sheet metal forming is exposed to the same challenges as the automotive industry. The continuously increasing demand on lower consumption and lower CO2 emission means the highest challenges on materials developments besides design and construction. As a general requirem...

Purpose: Of this paper is to give a general overview about the recent developments in sheet metal forming, with special regards to the needs of automotive industry as the main driving force behind these developments. Design/methodology/approach: First a general overview of material developments concerning the sheet metal forming will be given inclu...

Car manufacturing was always the key industry behind sheet metal forming thus the requirements and developments in car manufacturing have decisive role in the development of sheet metal forming, too. The automotive industry faces with very contradictory demands and requirements: better performance with lower consumption and lower harmful emissions,...

In this paper some recent material developments will be overviewed mainly from the point of view of automotive industry. In car industry, metal forming is one of the most important manufacturing processes imposing severe restrictions on materials; these are often contradictory requirements, e.g. high strength simultaneously with good formability, e...

In this paper, some recent developments in materials applied in sheet metal forming processes will be overviewed mainly from the viewpoint of automotive industry as one of the most important application fields. If we consider the main requirements in the automotive industry we can state that there are very contradictory demands on developments. Bet...

Sheet metal forming is one of the most important key technologies in manufacturing industry. It may be reasoned by several facts, among them the economy of the sheet-forming processes concerning the material and energy consumption, as well as the overall cost efficiency. To keep this key role of sheet metal forming in manufacturing industry, a cont...

During the recent 10-15 years, Computer Aided Process Planning and Die Design evolved as one of the most important engineering tools in sheet metal forming, particularly in the automotive industry. This emerging role is strongly emphasized by the rapid development of Finite Element Modeling, as well. The purpose of this paper is to give a general o...

The need for flexible forming processes is of utmost importance in the recent years. Therefore, it is very important to develop new innovative technologies and processes. This is particularly valid for small batch and prototype production. Incremental sheet metal forming may be regarded as one of the promising developments for these purposes. In th...

Nitriding is one of the most important processes among surface technologies. The purpose of this process is to produce a wear resistant layer on the surface of components, to meet the complex requirements. Ferritic nitrocarburising was carried out at three different temperatures (520, 570 and 620°C) and with five different process times, to study t...

Purpose: The aim of this research paper is to give a general overview on sheet incremental forming as an emerging field in small and batch production.Design/methodology/approach: First the historical and literature background of sheet incremental forming will be given, and then some theoretical and practical issues of the incremental forming proces...

Development of new technologies and processes for small batch and prototype production of sheet metal components has a very important role in the recent years. The reason is the quick and efficient response to the market demands. For this reasons new manufacturing concepts have to be developed in order to enable a fast and reliable production of co...

In this paper, some relevant issues concerning an innovative sheet metal forming method, a milling machine-based Dieless Incremental Sheet Forming (DSF) will be analyzed. The experimental setup is based on the replacement of the commonly used dies by a second forming (Slave) tool where the movement is synchronized with the first forming (Master) to...

Forming limit curves are very important for the prediction of failure during sheet metal forming both in practical forming operations and particularly in numerical simulations. The reliability of numerical simulations in sheet metal forming processes is strongly influenced by the reliability of forming limit curves. Therefore, both the theoretical...

During the recent 10-15 years, Computer Aided Process Planning and Die Design evolved as one of the most important engineering tools in sheet metal forming, particularly in the automotive industry. This emerging role is strongly emphasized by the rapid development of Finite Element Modelling, as well. In this paper, an integrated process simulation...

In this paper, first, the state of the art of numerical modelling in hot forming processes will be overviewed. Then the paper briefly reviews the theoretical background of metal forming simulation, including the basic constitutive equations, and the information flow in process modelling. The important process variables and the main characteristics...

The increased competition in the automotive industry leads to a great model variety with increasing demand to shorten model cycles and to reduce lead times at a decreasing cost level. This requires a special response from car manufacturers to realise a more flexible and simultaneously more standardised manufacturing of vehicles applying new materia...

Purpose: of this paper: During the recent 10-15 years, Computer Aided Process Planning and Die Design evolved as one of the most important engineering tools in sheet metal forming, particularly in the automotive industry. This emerging role is strongly emphasized by the rapid development of Finite Element Modelling, as well. The purpose of this pap...

During the recent years, due to the rapid development in Finite Element modeling, as well as the rapid evolution of computer techniques, numerical modeling has become an important everyday tool not only for process analysis and process optimization but for die design and rapid die manufacturing, as well. The Department of Mechanical Technology at t...

The application of numerical modelling and simulation in manufacturing technologies is looking back for about a twenty-thirty years history. In recent years, the role of modelling and simulation in engineering and in manufacturing industry has been continuously increasing. This is well known that during manufacturing processes simultaneous effect o...

The application of numerical modelling and simulation in manufacturing technologies is looking back over about a 20–30 years history. In recent years, the role of modelling and simulation in engineering and in manufacturing industry has been continuously increasing. It is well known that during manufacturing processes simultaneous the effect of man...

In recent years, research focus has shifted from the initial objective (in sheet metal forming often restricted to ``simple'' formability analysis) to global quality control and an overall process integration. Therefore, in manufacturing industry, it is absolutely essential to include the entire process chain in simulations in an integrated virtual...

in the process of joining metal and ceramics, several publications deals with the experimental and numerical analysis of the process. Many experiments were performed to find a better shape of the contact surface in order to get a better resistance of the joining. Several simulations were also presented for individual cases. In this work, we want to...

Deep drawing operation is a complex process, containing different interacting components, influenced by several parameters. These parameters can be divided into several groups: the press, die and part design, materials and lubricants applied during the operation. Furthermore, the interactions between these components are very difficult to evaluate....

With the increasing application of finite element systems, new requirements appear for the more exact description of materials. It is manifested in the demand for deeper know- ledge of yield criteria, and other basic equations describing the material behaviour. Further- more, the recent requirements in sheet metal forming concerning the faster and...

In this paper some new results are presented on the development of a Knowledge Based Expert Systems for metal forming applications. The system is aimed to be capable of generating feasible process plans for various sheet and bulk metal forming modules. The elaboration of this expert system is based on the principles of group technology. A hybrid co...

In this paper an integrated CAD/CAM system for sheet-metal forming processess is presented. The paper briefly outlines the general structure of this program package and describes in detail its main modules, the geometric description, the layout design, the technological and tool design modules will especially be emphasized. The total system is base...