The applications of thermal spray-coating are numerous and widespread from non-stick pans and irons, via engine parts and turbine blades to medical implants. The coatings serve primarily to protect the underlying surfaces from mechanical and thermal load, or chemical attack. Staff at the Empa Thun have made an internationally recognized contribution to the success of this new technology with their work over the past eleven years in the sole Swiss institution developing materials and coatings, and conducting scientific research in the field of thermal spraying.
Some of the newest research results were on show in Basel, for example nanopowders which serve as the raw materials for several processes involving thermal spray-coating. The powders consist of particles with diameters below 100 nanometers, and when compared to the original materials from which they are made they have new and startlingly different properties. With its two newly completed pilot plants, the Empa is now able to produce tailor made nanopowders at a rate of kilograms per hour.
Another current Empa development is a continuously porous and yet extremely strong titanium coating for hip replacement implants. This novel surface allows significantly better binding between the patients bone and the implant, because the coating consists of connected pores throughout its thickness. The bone cells can thus grow though the entire depth of the surface.
In addition to these developments, the Empa also demonstrated a new method of measuring the adhesion of deposited layers, a cooperative project involving other European research institutes and supported by Swiss industrial partners. The new technique permits researchers to measure cohesive or adhesive failure of a surface layer that is to say fractures within the coating, or separation of the coating from the substrate at the boundary surface. An instrument which operates using the new technique is already commercially available, and its use is expected to lead to a proposal for establishing a new European and international standard.
Over the three days, the ITSC offered a wealth of state of the art information. The conference program included 229 lectures, 90 posters and an exhibition with over 30 stands presenting internationally leading companies. In addition, an industry forum was used to demonstrate practical applications and introduce selected firms. The conference was organized by the American Society of Materials Thermal Spray Society (ASM-TSS), the International Institute of Welding (IIW) and the German Association for Welding and Related Techniques (DVS).
Author: Dr. Bärbel Zierl
Dr. Stephan Siegmann, Head, Empa Coatings Laboratory, Tel. 033 228 29 45, firstname.lastname@example.org