8th HVOF Colloquium 2009 in Erding presents the state of the art

“High-speed coatings” for engineering surfaces

Prof. H. Kreye, C. Penszior, P. Heinrich

The colloquium “High Velocity Oxy-Fuel Flame Spraying” has long established itself as the world’s largest conference for this specialist field of thermal spraying. In November 2009, the colloquium took place for the 8th time, with the Civic Hall in Erding near Munich hosting this international thermal spray event for the 5th time, having also been the venue in 1997, 2000, 2003 and 2006.

On 5 and 6 November 2009, 25 technical presentations and 21 exhibitors provided the 420 attendees from 23 countries with the latest information and developments in the field of HVOF and cold spraying. The 8th HVOF Colloquium therefore successfully followed on from previous events in this series of conferences. The new concept of bringing the presentations, exhibitors and supporting program (meals, breaks, etc.) closer together was even more conducive to keen conversation, technical exchanges and, of course, business dealings.

View into the auditorium of the Civic Hall in Erding during the 8th HVOF Colloquium.

According to Peter Heinrich, in charge of organizing the event, the key to the colloquium’s success is that the organizers always have the “central theme” of the conference very clearly in mind, right from the planning stages, and carefully select the topics and speakers accordingly. This guarantees that the colloquium reflects cutting-edge HVOF technology and takes into account contemporary trends. The extremely positive feedback received from the participants endorses this concept devised by the organizers, the Association of Thermal Sprayers (GTS e.V.), the Helmut Schmidt University of the Federal Armed Forces and Linde AG, Linde Gas Division.

Theory and practice hand in hand
On the first day of the colloquium, experts from research and industry presented the latest technology and developments from the field of thermal spraying. Once again, a focal point of the presentations was the process high velocity oxy-fuel flame spraying (HVOF), which is now virtually a standard facility in every coating business and for which there are currently around 300 spray systems in German-speaking countries alone. Both gas-driven and kerosene-driven spray systems from a variety of manufacturers have been technically refined to a very high level with respect to optimum fuel utilization for heating and accelerating the powder particles. The main domain of HVOF spraying is still the production of metal-carbide coatings for wear and corrosion protection in practically all sectors of industry. Several presentations at the colloquium reported on how the various spray systems can be applied to optimize coating properties for particular stress cases by appropriately adjusting the process and powder parameters.

Prof. Kirsten Bobzin, Head of IOT at the RWTH University Aachen and President of GTS, speaking to more than 420 participants from 23 countries. Ample space for conversation and networking –
participants at the exhibition directly adjacent to the

A second focal point of the colloquium was the relatively new process, cold spraying, first invented by Russian scientists and further developed and made ready for market by the Helmut Schmidt University Hamburg, Linde AG and CGT Cold Gas Technology GmbH Ampfing. By utilizing a wide range of metals and alloys, the possibility of manufacturing extremely dense and oxide-free coatings, whose properties come close to matching the values of solid material produced with metal fusion bonding, has opened up a window of opportunity for new thermal spray applications. In addition to presenting detailed process analyses and process equipment which is now commercially available, a large number of examples illustrated the industrial manufacture and application of coatings. These further underscored the potential of this new coating method.

Alternative methods for new areas of application
Yet another series of presentations dealt with new developments in plasma spraying and arc spraying. Besides the air plasma (APS) torches with one pair of electrodes, already widely used in industry today, new torches with three cathodes now provide higher deposition efficiency and enhanced process stability. However, it would seem that the broad spectrum of possibilities which plasma spraying already has to offer has not yet been exhausted. Multi-cathode and multi-anode technology as well as the fluid dynamic adaption of nozzle configurations have now been joined by further plasma spray developments, such as the trend to higher particle velocities. Arc spraying also promises further potential for new developments. By using shielding gases or mixtures of shielding gases and reactive gases to atomize the spray particles, it was possible to demonstrate how the burn-off of alloying elements and the oxide content in the coating could be reduced.

An important resource when developing new spray processes and systems are the diagnostic methods which measure and record the particle temperature and velocity. A paper by the University of the Federal Armed Forces Munich looked at the variety of means available to achieve this. Here, special emphasis was given to those methods which can also be used to monitor spray processes.

Of increasing importance: quality and certification
The second day started off with a series of presentations which confirmed how invaluable and also indispensable it is to provide and have thorough and comprehensive education and training, a systematic set of rules and regulations in the form of standards and technical bulletins as well as an effective quality assurance and certification system for thermal spraying. The major role a well-organized association can play here was well illustrated by the unique and very clear certification rules which GTS (Association of Thermal Sprayers) has compiled. Thanks to GTS activities, thermal spraying is decidedly better organized than many other technologies.

Practical findings
Reports from industry provided numerous examples of applications from the so-called “borderland” of thermal spraying. Speakers explained which criteria should be applied when selecting a process or a spray material in order to achieve optimum quality combined with high cost-effectiveness. Other presentations dealt with the advent of nanotechnology in relation to HVOF-sprayed tungsten-carbide coatings. Yet another impressive report from CSIRO in Australia focussed on the close cooperation between the CSIRO research centre and its various industrial partners. With the backing of state funding programs, these joint activities have helped to implement the cold spray applications already available and provide the necessary impetus for new investigations.

Trendsetting developments
The diversity of HVOF developments and applications presented at the colloquium aroused the audience’s expectations and interest in no uncertain terms. Once again, it became very clear that the range of applications for this technology has by no means been exhausted and that the active cooperation between the research sector and material and equipment manufacturers will constantly help to make inroads into new fields of application and enhance those which already exist. Very much worth noting as a “trendsetting” development are some of the observations made at the end of the two-day conference: many experts who had previously viewed cold spraying with a somewhat critical eye came to the conclusion that this coating technology, with its many existing applications, had in fact already established itself on the market and can now look forward to an extremely prosperous future. The organizers of the HVOF Colloquium will continue to closely monitor and accompany the developments in the field of high velocity oxy-fuel flame spraying – and who knows: maybe, in the near future, we will see each other again in Erding and can verify this progress together.


8th HVOF Colloquium 2009 as seen by one of the participants

“Important – especially when the economy is fraught with tension”

Bernd Abler

In November 2009, the HVOF Colloquium took place in Erding for the 8th time. For us, the company ABLER GmbH & Co. KG, a service provider in the field of thermal spray coatings, this event has come to play an extremely important role. It is now indispensable in the series of colloquia and technical conferences.

Once again, the 8th HVOF Colloquium gave us as users a compact insight into current areas of research from a variety of thermal spray fields. To a certain extent, these also offer a high potential for practical implementation and therefore prospects for possible new applications. Furthermore, the series of lectures included presentations on the latest systems and processes as well as innovations in spray materials. This enables users to design their own production processes more economically and effectively by integrating specific updates into such processes. This year, the series of lectures “Reports from our Practitioners” on the second day of the colloquium again met with a very favourable response. Here, companies in similar or identical lines of business could input and exchange their experiences with the implementation of new applications and processes.

As in previous years, especially deserving of praise was the excellent and professional manner in which the hosts GTS, LINDE AG and the Helmut Schmidt University Hamburg organized the colloquium. The extremely positive atmosphere throughout the entire conference, numerous opportunities for enjoyable conversation among the participants and visitors and a successful supporting program and catering service rounded off, what we think, was again an outstanding event.

UPSHOT: Especially when the economy is fraught with tension as is now the case everywhere, it is more important than ever to organize and attend such events as the HVOF Colloquium. For us as users, this was again an absolute imperative in 2009. The need to stay up-to-date in the field of HVOF spraying and other related coating processes and to help extend their use and increase public awareness of the technology was not even subject to negotiation when we made our decision to attend the HVOF Colloquium.






Last updated: 22.12.16 Home Copyright (C) 2010 GTS e.V.