erc 2010 stg partb1 chaosweld

Suban Part B1 ChaosWeld

1

European Research Council

ERC Starting Grant Research proposal (Part B1)

New approach to welding control using chaos theory

ChaosWeld

FOR MORE INFORMATIONS VISIT http://sites.google.com/site/chaosweld/

- Name of the Principal Investigator (PI) Marjan Suban

- Name of the PI's host institution for the project Institut za metalne konstrukcije

- Proposal full title New approach to welding control using chaos theory

- Proposal short name ChaosWeld

- Proposal duration in months 60 months

In arc welding processes, the knowledge of material transfer (electrode melting, droplet formation and transfer to the weld pool) is essential to analysis and control of welding process. This is especially important in welding processes, which are used in automation or robotisation, where more stable welding process is required (e.g. MIG/MAG). Material transfer mode affects stability of the welding process, which finally affects the quality of welded joints. For many years, the welding community has assumed that the material transfer is stohastic process. In early studies in 1999 and 2000, we have already indicated that it is possible to detected signs of chaotic behavior in the short circuiting transfer. In later studies it was found that the chaotic behavior also appearing in globular transfer of material. The current state of welding technology enables stable transfer of material using pulse mode welding. The material transfer from the electrode to the weld is subject to high energy puls forming drop and forces it to move into weld pool during one pulse. Disadvantages of this welding mode are many, such as high energy consumption, high energy input in the weld, a strong UV radiation in the surrounding area, the inadequacy for root welding etc. Given the above, one can conclude the following. If the process of material transfer from electrode to the weld pool is chaotic and not stohastic, then it’s possible to achieve stable transfer and thereby stable welding process using the theory of chaos control. One of the characteristics of the chaotic process is sensitivity to initial conditions. If we apply an approach that is used in heart pacemakers, then the process of material transfer and thereby the welding process can be controlled by very small system perturbations, which can lead to stable and predictable process. This method of control the welding process could have revolutionary impact on the design of welding equipment and related control systems.


2

Section 1: The Principal Investigator 1(a) Scientific Leadership Potential My interest for the welding domain already originate from my home environment. On this basis, I have built my way of education. After completing undergraduate studies where I was in last year decided for a module "welding and cutting", I have on the basis of good grades obtaining a fellowship in the program "Young researchers" by the Ministry of Science and Technology (now Ministry of Higher Education, Science and Technology ). Based on the obtained grant I got a job at the Institute of welding in Ljubljana as a researcher and began post-graduate study. During this time I also completed post-graduate specialization for European Welding Engineer EWE, which has brought me additional practical knowledge of welding and cutting. As young researcher I successfully completed the postgraduate studies in the field of High-production fusion arc welding in various shielding media. In the Master’s thesis, investigation was made including research on welding productivity and latest variations of MIG/MAG welding processes. MIG/MAG welding processes was my main research object with different types of wire and also various shielding gases. During the study of the subject »Synergetics«, I came familiar with the theory of chaos, which until then I did not sufficiently known. On the basis of knowledge in the study of this subject and knowledge which I already have in the field of MIG/MAG welding process in 1999 I came to the idea that it would be possible to combine these two disciplines together. Thus began my research in the field of chaos theory in welding and in year 2000 I presented my work on 53rd IIW Annual Assembly in Florence, Study group 212 (Physics of welding) in a form of lecture and document No. 212-985-00 with title »The chaotic behaviour of the material transfer in GMAW: preliminary report«. Presented paper treated some thoughts on the analysis of the material transfer during gas-shielded metal-arc welding based on nonlinear dynamics. Based on chaos theory and research work on dripping faucet by other researchers, some similarities can be found between the material transfer in GMAW and the water drops falling from a dripping faucet, which is one of the basic models of chaotic system. In this preliminary study I have also pointed out the direction on further research work in area of arc control.This can lead to improved arc stability, which is important for determination of weld quality. During this period, beside mentioned areas, I also participated in many research areas or projects, such as the before mentioned research of productivity of welding, welding process stability, quality of welded joints and environmental problems of welding and soldering. My first large scale project that I conducted under the supervision of project leader dr. Janez Tušek was entitled »High-productivity arc welding«. Project results were also applicable from the industry point of view. The common subject of all the projects in which I participated was welding and allied processes. In implementing the projects I have successfully worked with various leaders. This period was very fruitful in a research sense, since in this period also derive most of my publications in scientific literature. Published contributions were of interest to other researchers, since I have gained some citations. In this period, I was promoted as Head of Training Center at the Institute of welding. I was mainly involved in the implementation of European and internationally recognized post-graduate specialization for welding technologists EWT, engineers EWE and inspectors EWI in Slovenia as well as in Serbia. In this field, I worked tightly with European Federation for Welding, Joining and Cutting EWF and International Institute of Welding IIW/IIS, commission C-XIV Education and


3

training. At that time, the opportunity was offered to me to begin post-graduate study at the Faculty of Economics in Ljubljana. I started study entrepreneurship in year 2007, which I still attended. I have plan to finish study in year 2010. I continue to Ph.D. study, where I also was co-financed by the Ministry of Science and Technology. While studying I had to change jobs, so I went to the company Goodyear EPE, where I also got a job in R&D departament. This area was new for me, because I had to get to know the rubber products and their characteristics. In this company I completed my Doctoral study, by the fact that I had allowed partial access to research equipment that I had at the Institute of welding. The thesis I have also discussed productivity in MIG/MAG welding, but mentor dr. Janez Tušek and I set the task in a different way. Goal of the thesis was design and development of welding equipment and research of gas shielded pulsed welding technology using three wires. New and in some way innovative welding machine was built. Unlike existing welding machines, the essence of our machine was in a single welding power source with a newly developed control electronics. The welding equipment developed satisfied all the demands for stable pulsed welding using multiple-wire and it results in an increase of productivity. Developed welding equipment remained the property of the Institute of welding, but further development as well as potential marketing never occur. Working in the company Goodyear EPE was extremely project oriented with a lot off team work. For the various producers (Scania, Volvo, Renault) I participated in development projects for trucks and buses suspension. There was a lot of research work within the Goodyear company itself, but this was mainly focussed on the development of rubber products and their testing. Together with the head of development for Europe we founded a research group in the company that also participated in three national projects and one international research project. Publication of articles from this period are rare, since the results of research group were often treated as business secrets. With global sale of division, development in the company Goodyear EPE was reduced, so I was forced to change job and I went to the Ministry of Higher Education, Science and Technology. With this, I break the job in research field. At the time of service at Ministry I was involved in the creation of science policy in particular in the transfer of knowledge from the academic sphere in the industry. Based on the successful work, national achievements in the transfer of knowledge was internationally presented as one of the five examples of good practice in Europe. Following the work in the company Litostroj Steel, where I worked on the project of purchase and start-up foundry in Serbia, I came to the Institute for metal constructions as Head of R&D. With this I again returned to the research field. Institute in the past was very strong national institute in the development of steel welded structures. In recent years the development of the Institute has declined and that it should be reinvigorated. This offered me the opportunity to re-engage in research work in the field of welding. Reestablishment research group at the Institute is for me challenge which I’am currently facing. This grant application is an element of this mission, to build a excellent research team, which in the future will produce great results. Self Evaluation I have a twelve years long experience as a researcher, where nine years are in a field of welding and allied processes. I think I have strong background in formal and additional education. My work in many different projects was respected. I worked in project teams with different project leadears mainly as a researcher. I just started to apply for a funding as a project leader. I have also a education and experiences in the field of finances and a science policy (beside illness this time also represent my research career break). Thus I think that all these skills demonstrate my potential to become a good independent research leader.


4

1(b) Curriculum Vitae Education 2007 - M. Sc. study Entrepreneurship

University of Ljubljana, Faculty of economics 2000 - 2004 Ph. D., 14 Dec. 2004

University of Ljubljana, Faculty of Mechanical Engineering 1995 - 1998 M. Sc.

University of Ljubljana, Faculty of Mechanical Engineering 1989 - 1994 B. Sc.

University of Ljubljana, Faculty of Mechanical Engineering 1984 - 1988 Technician

Secondary school of Mechanical Engineering, Ljubljana Additional Education: 2007 Project and Programme Manager

Europe Training Center Paris 1994 European Welding Engineer (postgraduate specialization)

Institute of welding, Ljubljana Professional Experience 2009- Head of R&D

Institut za metalne konstrukcije, Ljubljana (Institute of metal constructions) 2008 - 2008 Project leader

Litostroj Jeklo, Ljubljana (Litostroj Steel) 2006 - 2008 Undersecretary

Ministrstvo za visoko šolstvo,znanost in tehnologijo (Ministry of higher education, science and technology)

2002 - 2006 R&D engineer Goodyear EPE, Kranj

1997 - 2002 Head of Training Center Institut za varilstvo, Ljubljana (Institute of welding)

1994 - 1997 Researcher Institut za varilstvo, Ljubljana (Institute of welding)

Teaching Experience 1996 - 2002 Lecturer (welding processes, metal constructions), postgraduate specialization for

European Welding Personal, Institut za varilstvo, Ljubljana (Institute of welding) 1998 - 2000 Assistent, University of Ljubljana, Faculty of Mechanical Engineering Professional Membership 1994 - Zveza drustev za varilno tehniko Slovenije (Slovenian Welding Society) 1996 - 2002 International Institute of Welding IIW/IIS, national delegate in study group SG-212

The physics of welding, commission C-XII Arc welding processes and production systems and commission C-XIV Education and training

Fellowship 1999 - 2001 Young researcher (Ph. D. study), Ministry of Science and Technology 1995 - 1997 Young researcher (M. Sc. study), Ministry of Science and Technology


5

Collaboration in National research groups (Slovenian Research Agency) 2009 - 0218-001: Institut za metalne konstrukcije (Institute for metal constructions), Head

of research group 2002 - 2006 Goodyear EPE, Researcher 1994 - 2002 0209-001: Institut za varilstvo (Institute of welding), Researcher Research Projects 2005 - 2008 »Development of forecast tools for drive belts endurance«, L2-7288 Slovenian

Research Agency, Faculty of Mechanical Engineering in collaboration with Goodyear EPE (with dr. Marko Nagode as Project Leader), � 165.200

2005 - 2006 »Characterization of the failure mechanisms of elastomer composites under cyclic loads«, Institute of Materials Science and Testing of Plastics, University of Leoben, Leoben, Austria, Polymer Competence Center Leoben GmbH, Leoben, Austria co-operation contract with Goodyear EPE (with dr. Zoltan Major as Project Leader), � 153.000

2004 - 2005 »Laser triangulation method in shape measurement of rubber products«, Faculty of Mechanical Engineering co-operation contract with Goodyear EPE (with dr. Janez Mozina as Project Leader), � 88.000

2002 - 2004 »Lack of fusion in MAG welding of high-strenght steels«, L2-4409 Ministry of Education, Science and Sport, Researcher (with dr. Gabriel Rihar as Project Leader), � 52.200

2001 - 2004 »TIG welding of austenitic stainless steels in a protective atmosphere of nitrogen«, L2-3252 Ministry for Education, Science and Sport, Researcher (with dr. Borut Zorc as Project Leader), � 280.900

2000 - 2002 »Replacement of materials and technology of soldering for melting elements application«, L2-2241 Ministry of Science and Technology, Researcher (with dr. Janez Tusek as Project Leader), � 87.400

2000 - 2002 »Effect of welding procedures and parameters on the mechanical properties of welds of different aluminum alloys«, L2-2167 Ministry of Science and Technology, Researcher (with dr. Gabriel Rihar as Project Leader), � 112.500

1999 - 2003 »Transfer of welding multimedia software – WELDICTION«, Leonardo da Vinci project Nr. EUR/99/2/07364/PI/II.1.1B/FPC, Researcher

1999 - 2001 »Manufacturing and processing of working surfaces of tools by welding«, L2-1649 Ministry of Science and Technology, Researcher (with dr. Janez Tusek as Project Leader), � 115.300

1997 - 1998 »Welding of high pressure gas pipelines in service«, L2-9067 Ministry of Science and Technology, Researcher (with dr. Gabriel Rihar as Project Leader), � 74.100

1996 - 1998 »High-productivity arc welding«, L2-7642 Ministry of Science and Technology, Researcher (with dr. Janez Tusek as Project Leader), � 231.800

Funding ID I’am employed for a specified period till 31.5.2009 with possibility of employment for an indefinite period at the Institut za metalne konstrukcije as Head of R&D. At a moment I’am not receiving any research grant or fellowship. There is one ongoing application, where results will be known on 9.4.2010, with following details: 2010 - 2012 »Study of effects on the initiation and development of microbial influenced

corrosion«, Slovenian Research Agency, Project Leader Marjan Suban, � 110.000 Significant Career Break nov. 2008 - maj 2009 Long-term illness maj 2006 - apr. 2008 Employment in Non-Research Institution nov. 2005 - apr. 2006 Long-term illness


6

1(c) Early Achievement-Track-Record Citation report for Marjan Suban (source WoS): Results found:8 Sum of Times Cited: 59 Average Citations per Item: 7,38 Publications without the PhD Supervisor (dr. Janez Tusek) SUBAN, Marjan. Determination of stability of MIG/MAG welding process. Qual. reliab. eng. int., 2001, Vol. 17, No. 5, pp. 345-353. [COBISS.SI-ID 861633], Times cited: 2 Description: The paper treats several methods of evaluating the stability of MIG/MAG welding processes, which are based on measurement of time-varying welding-current intensity and welding voltage. Publications with the PhD Supervisor (dr. Janez Tusek) SUBAN, Marjan, TUSEK, Janez. Methods for the determination of arc stability. J. mater. process. technol.. [Print ed.], 2003, Vol. 143, Special Issue., pp. 430-437, Times cited: 2 Description: The methods described in the paper are based on measurement of time-varying welding current and welding voltage. Stability analysis was carried out with different gas-shielding atmospheres. TUŠEK, Janez, SUBAN, Marjan. High-productivity multiple-wire submerged-arc welding and cladding with metal-powder addition. J. mater. process. technol.. [Print ed.], 2003, Vol. 133, No. 1/2, pp. 207-213. [COBISS.SI-ID 5627163], Times cited: 6 Description: It was found that the multiple-wire submerged-arc welding and cladding with metal-powder addition will increase the deposition rate, and the welding-arc efficiency and reduce the shielding-flux consumption. SUBAN, Marjan, TUŠEK, Janez. Dependence of melting rate in MIG/MAG welding on the type of shielding gas used. J. mater. process. technol.. [Print ed.], 2001, Vol. 119, No. 1/3, special issue "AMPT'99", part 2, pp. 185-192. [COBISS.SI-ID 4892443], Times cited: 12 Description: The paper describes a study on welding productivity, i.e. melting efficiency of the filler material (solid and cored wires) in various shielding media. A mathematical model for prediction of a melting rate is presented too. SUBAN, Marjan, TUŠEK, Janez, URAN, Miro. Use of hydrogen in welding engineering in former times and today. J. mater. process. technol.. [Print ed.], 2001, Vol. 119, No. 1/3, special issue "AMPT'99", part 2, pp. 193-198. [COBISS.SI-ID 4892699], Times cited: 2 Description: This paper deals with the history of the use of hydrogen as a combustible or shielding gas in welding and with a study on the use of an argon mixture containing a larger portion of hydrogen in TIG and MIG welding processes. TUŠEK, Janez, KAMPUŠ, Zlatko, SUBAN, Marjan. Welding of tailored blanks of different materials. J. mater. process. technol.. [Print ed.], 2001, Vol. 119, No. 1/3, special issue "AMPT'99", part 2, pp. 180-184. [COBISS.SI-ID 4892187], Times cited: 5


7

Description: Article treats selection of appropriate welding procedure of tailored blanks made of high-alloy stainless and low-alloyed ferrite steel. TUŠEK, Janez, SUBAN, Marjan. Experimental research of the effect of hydrogen in argon as a shielding gas in arc welding of high alloy stainless steel. Int. j. hydrogen energy. [Print ed.], 2000, Vol. 25, pp. 369-376. [COBISS.SI-ID 473537], Times cited: 13 Description: Effect of hydrogen in argon as a shielding gas in TIG and MIG welding of austenitic stainless steel on arc stability and melting efficiency is studied. TUŠEK, Janez, SUBAN, Marjan. Hybrid welding with arc and laser beam. Sci. technol. weld. join., 1999, Vol. 4, No. 5, pp. 308-311, [COBISS.SI-ID 424129], Times cited: 15 Description: The major part of the paper is focused on the combined action of a welding arc and a laser beam (synergic action of two different heat sources for fusion welding). The main advantage of the use of both heat sources is more efficient use of the energy supplied. Publications in peer-reviewed conferences proceedings SUBAN, Marjan, TUŠEK, Janez. The effect of the shape of welding wire tip on arc ignition in MIG/MAG welding. V: TORRALBA, José M. (editor). Proccedings of the International Conference on Advanced Materials Processing Technologies (AMPT'01), 18-21 September, Universidad Carlos III de Madrid, Leganés, [Madrid], Spain. Vol. 1, New developments on metals. [Madrid]: Universidad Carlos III de Madrid, 2001, Vol. 1, pp. 447-453. [COBISS.SI-ID 832193] Description: Invited Presentation PICIGA, Darja, SUBAN, Marjan. Technology transfer area: Presentation of "A Center of excellence" (Slovenia) : [invited lecture on Fostering regional innovation in Europe: Novaregio Best Practices Showcase, Santa Cruz de Tenerife, Instituto Technologico de Canaries S.A., 4th October 2007}. Santa Cruz de Tenerife, 2007. [COBISS.SI-ID 1030337] Description: The concept of Centres of excellence (Ministry of Higher Education, Science and Technology) was presented as one of the five best practice of knowledge transfer from the academic sphere in the industry in Europe. Peer-reviewer for International Journals Journal of Materials Processing Technology, Impact Factor: 1.143 Optics and Lasers in Engineering, Impact Factor: 1.103 Organisation of International Conferences 54th Annual Assembly of the International Institute of Welding IIW/IIS in Ljubljana, July 2001 (organizing committe member) Organisation of National Conferences with International Participants Dan varilne tehnike (Day of welding) 2000 in Ljubljana, 2001 in Krsko and 2002 in Portoroz (organizing committe member) Membership in Editorial Boards 2nd Dan varilne tehnike, Ljubljana, 13. april 2000, POLAJNAR, Ivan (editor), SUBAN, Marjan (editor). Proceedings. Ljubljana: Društvo za varilno tehniko, 2000. 181 pages, ilustrations [COBISS.SI-ID 106907904] 4th Dan varilne tehnike, Portorož, Koper, 23. May 2002, POLAJNAR, Ivan (editor), SUBAN, Marjan (editor). Proceedings. Portorož: The Faculty of Maritime Studies and Transport, 2002. 203 pages., ilustrations. ISBN 961-6044-50-8. [COBISS.SI-ID 118397440]


8

Section 1d: Extended Synopsis of the project proposal The gas shielded metal arc welding (MIG or GMAW) process was successfully developed in 1948 in USA. One of the basic changes that made the process more usable was the small-diameter electrode wires and the constant-voltage power source. The initial introduction of GMAW was for welding nonferrous metals. The high deposition rate led users to try the process on steel. The cost of inert gas was relatively high and the cost savings were not immediately available. In 1953, Russian researcher announced the use of welding with consumable electrodes in an atmosphere of CO2 gas. The MAG welding process immediately gained favor since it utilized equipment developed for inert gas metal arc welding, but could now be used for economically welding steels. The process became widely used with the introduction of smaller-diameter electrode wires and refined power supplies. Another variation was the use of inert gas with small amounts of oxygen that provided the spray-type arc transfer. It became popular in the early 1960s. A recent variation is the use of pulsed current. The current is switched from a high to a low value at a rate of once or twice the line frequency. With pulsed current material transfer can be controlled, but pulsed current have also some others limitations (not suitable for root welds, high UV radiation, etc.). In 1990 with inverter-based power sources many others welding process control was developed in order to control material transfer from wire to the weld pool. As example, one of this was Surface Tension Transfer ™ in late 1993. As shown in this history review a lot of research work was put in the development of stable material transfer where we can achieve high productivity of welding with low energy consumption. This is especially important with the introduction of automation and robotisation in industry where it also requires real-time monitoring and control of welding processes. Further development in this area is obvious. Material transfer most be fully controllable in any mode of welding, from low to high welding current, for thin or thick sheets of metal. Is material transfer in welding stochastic or deterministic process? We know that it is not deterministic. So, it must be stochastic. But what if it is non of this. What if it is Chaotic? Dynamical systems are »deterministic« if there is a unique consequent to every state, and »stochastic« or »random« if there is more than one consequent chosen from some probability distribution (the »perfect« coin toss has two consequents with equal probability for each initial state). But there also exists a system, which contains »deterministic« and »stohastic« properties and is called »chaotic system«. It has been said that »Chaos is a name for any order that produces confusion in our minds«. However, the mathematical definition is, roughly speaking: chaos; effectively unpredictable long time behavior arising in a deterministic dynamical system because of sensitivity to initial conditions. Some nonlinear systems which display deterministic chaos are: forced pendulum, lasers, nonlinear optics devices, chemical reactions, plasmas with interacting nonlinear waves, stimulated heart cells, etc. In 1977 Rössler suggested that the drops falling from the leaky faucet might provide a familiar example of a dynamical system capable of exhibiting chaotic behavior. The dripping faucet is since then well known model system, used for illustrating the appearance of chaotic behavior in nonlinear systems. The experiment (see Fig. 1) studies the statistic of liquid drops dripping from a leaky tap when the mean dripping rate (control parameter of system) is increased.


9

Figure 1: Schematic setup of the apparatus of dripping faucet

As I was looking at drops falling from a dripping faucet, I saw in my mind similarity between this process and material transfer in gas-shielded metal arc welding or MIG/MAG for short, where a material separates from the molten wire as a droplet and "falls" to the plate. The physics of the droplet transfer process is more complicated than that of the dripping faucet. In addition to surface tension and gravity, and the interaction with the power supply dynamical response, the conducting droplets are subjected to complicated electromagnetic forces, along with arc plasma forces. Nonetheless, generic properties of the droplet release dynamics could just as well give rise to low dimensional dynamics as they can in the conceptually simpler, dripping faucet case. Indeed, in the globular mode, where the droplets are more massive, gravity and surface tension tend to dominate as they also do in the dripping faucet case. MIG/MAG welding process exhibits many different mode of material transfer. Principle transfer modes in MIG/MAG welding are: • short-circuit, • globular, • spray. The droplet events can be identified from visual observation of droplet processes (as in a case of dripping faucet – Fig. 1), or from air or plate-borne acoustic emission or from signature effects in weld voltage and current (Fig. 2). Perhaps, the most problematic will be observation of droplet separation in the spray mode because of the weakness of the event signatures. Construction of map time series with some missing points or extra points is not very competent. Based on measured time intervals we can diagnosticate them, with the emphasize on chaotic behavior. Some basic research was done in 1999 in 2000 when I have started to work in this research topic. Since then I have found only a few articles published on this matter. They were mainly dealing with search for chaotic behaviour in short-circuit or globular material transfer mode.


10

Figure 2: Material transfer in MIG/MAG welding (globular mode) The question is why we are trying to find chaotic behavior in material transfer? The answer is: controlling chaos. One of the basic properties which deterministic chaos manifests is »a sensitive dependence on initial conditions« (the butterfly effect). It becomes therefore practically impossible to predict the long-time behavior of these systems. It must be emphasized that a deterministic dynamical system is perfectly predictable given perfect knowledge of the initial condition, and is in practice always predictable in the short term. The key to long-term unpredictability is a property known as sensitivity to (or sensitive dependence on) initial conditions. Even if the behavior is chaotic, it can be controlled once the rules are known. Within the chaos exist unstable periodic orbits: state values that, if they were supplied and iterated with infinite precision, would repeat over and over. Of course, any slight imprecision in this state causes successive iterates to wander away from the cyclic order and take on the complexity of the chaotic attractor. Nonetheless, in some simple situations the chaotic dynamics can be forced to track arbitrarily close to a specified unstable orbit by aplying small, well-timed perturbations. The control of chaos by unstable periodic orbits embedded in a chaotic attractor was first originated in the work of others scientists. Furthermore, it is possible to switch efficently from one unstable periodic orbit to another. As mentioned befor we can use pulsed current so that material transfer can be controlled (see Figure 3). But this arise new problems. Puls of welding current forced melted droplet to transfer in exact time from welding wire to weld pool. Energy consumption is in this case large. Also high UV radiation of welding arc is one of the effects that welders don't like. In the case of chaotic behaviour of material transfer it can be controlled by vary small perturbations or pulses (see Figure 4-left) which can lead in a stable controlled droplet transfer.


11

Figure 3: Material transfer in pulsed arc welding (one drop per puls)

Figure 4: Typical form of pulsed welding current (left) and anticipated form of welding current

based on theory of chaos control (right) In short we can put research work in this project in following working packages. First working package will be identifying chaotic behaviour in material transfer in MIG/MAG welding. One of the steps in our research could also be searching for chaotic behavior in known mathematical models of MIG/MAG processes, such as different n-order nonlinear differential equations developed by others researchers or my research team.The next working package in our research work will be construction of an model for material transfer in different modes based on a model for the dripping faucet. Identification of chaotic behavior in the material transfer could permit the development of improved control of welding through well-known methods of control of chaos. Improved control can lead to improved arc stability, which is important for determination of weld quality. As final, prototype of welding control unit will be made. Findings in the field of MIG/MAG could then be transfered also to the other welding processes such as submergeed arc welding SAW or manual metal arc welding MMA.


12

Short economic background Results of this project will be usefull for a producers of welding equipment for semi or fully automated. In this field producers in Europe (the bigest are Germany, Austria, Finland, Sweden and France) represent 67% of world export or in total 1.173. mio USD. World exporters of welding machines with values (HS Code 851531 Elec mach&app for arc inc plasma arc weldg of met fully/partly auto) are also presented in Figure 5. Main importers of this products are Russian Federation, China and USA with total value of 496 mio USD.

Figure 5: Map of exporters for welding machines in 2008 (source COMTRADE)

erc 2010 stg partb1 chaosweld

Documents