Laser materials processing is well accepted in the Netherlands. About 150 sheet-metal fabrication shops have one or more laser cutters. Their customers like the improved edge quality compared to plasma cutter and punch nibbler. Where the first machines were laser-punch machines, the sheet metal suppliers now select mainly laser-only systems. One example is Staal Service Zuidbroek (Zuidbroek). The company started as a shipyard after WWII but became a sheet metal supplier in 1965 when the economy for shipbuilding in the Netherlands became more difficult. The company has one TRUMPF (Ditzingen, Germany) laser punch and two laser-only production units.
Many companies combine the supply of sheet metal with the fabrication of semi-finished products or even complete fine mechanical products based on customer specifications. For example the CMF Group, with headquarters in Heijen, has three CO2 systems and one Nd:YAG system from TRUMPF. One CO2 laser, a TLF 1005, used for welding has an integrated wire feed and it can be provided with a twin-spot optic, which makes the process more robust. The Nd:YAG laser is used for fine cutting. The CMF Group offers OEMs a broad spectrum of services such as co-engineering, tool design and manufacturing, and production of complete parts.
Eldim (Lomm), a subcontractor in the gas turbine industry, has used pulsed Nd:YAG lasers for drilling. Two Lumonics (Rugby, UK) lasers are used mainly for trepanning and an Omega laser (Convergent Prima; Chicopee, MA) is used for percussion drilling of film cooling holes in industrial gas turbine airfoils. Five years ago the company bought a Balliu (Lokeren, Belgium) laser system, powered by a Rofin-Sinar (Hamburg, Germany) laser, for cutting. A second CO2 laser system built by the same suppliers was recently introduced for welding and cutting of aero-engine components. The first laser is mainly used to cut details for super alloy backing plates and the second to cut slots in machined rings and to weld vanes in stator vane assemblies.
A limited number of "laser-only" job shops are specialists in typical market segments such as cladding, cleaning, and marking. A group of these companies is located near the University Twente (Enschede). Nedclad in Hengelo services its customers by applying claddings to improve the wear resistance of valves, camshafts and so on. Excimer laser cleaning is a speciality of Art Innovation (Hengelo). Industrial Laser Technology (Enschede) started back in 1986 as a shop for cutting using a Rofin-Sinar CO2 laser and now concentrates on marking, fine cutting, and welding of small high-tech components using pulsed (Lasag; Thun, Switzerland) and CW (TRUMPF; Schramburg, Germany) Nd:YAG lasers. Its founder, Paul Bant, says the competition in CO2 cutting has increased to such a level that it is moving out of that market segment.
Exilas (Helmond), founded by Hans van Esdonk, applies excimer lasers (Lambda Physik, Göttingen, Germany, and Radiant Dyes, Wermelskirchen, Germany) for material processing and offers application research and process development for customers. Activities include small-hole (sub-millimeter) drilling, product marking, surface cleaning (oxides, paint, grease), polishing, and metal-surface hardening.
Undoubtedly Philips, particularly its Centre for Fabrication Technology (CFT-Eindhoven), has played a crucial role in introducing laser materials processing in the Netherlands. At Philips CFT there is no longer a laser-only group. All kinds of laser applications are an integral part of the manufacturing group. Dr. Willem Hoving is the specialist and gatekeeper for laser material processing.
Inside the Philips organization there is also a high level of know-how on production automation. A group in Sittard has extended experience in the automation of laser welding and cutting of small components in mass production. This know-how is used to support other companies outside the Philips organization.
In the October issue of Industrial Laser Solutions the activities of Omega Laser Systems were mentioned. This company builds special systems on customer demand and it has developed moving optics for high-power CO2 lasers.
ASM (Veldhoven), one of the world's leading manufacturers of production units for manufacturing integrated circuits for the IC industry, is integrating UV lasers from Lambda Physik into its systems. Advanced Laser Separation International (Nijmegen) is developing and building systems for cutting silicon wafers.
At the University Twente Prof. Johan Meijer is chairing research in the field of laser materials processing. Currently the research is focusing on modeling of processes like keyhole welding. However, the group is also supporting Dutch industries in introducing processes like cladding, cutting, and welding. Part of the research is financed through the Netherlands Institute for Metal Research (NIMR). The laser group at the University Twente is participating with the Fachhochschule (Münster, Germany) in the EUREGIO application center whose mission is to service industry in the Netherlands as well as in Germany by performing applications research. They are also participating in the European Laser Application Network.
NIMR is an institute in which Dutch industries and universities participate to improve technology by defining and performing specific R&D projects. Research at the Technical University Delft (Prof. Richardson: laser-assisted plasma welding and diode laser welding) and at the University Groningen (Prof. De Hosson: cladding and surface treatment) is also supported by the NIMR. The laser facility at the application center of CORUS in Velzen is also participating in the activities of NIMR. This application center uses CW CO2 lasers (TRUMPF) to demonstrate processes to customers.
Netherlands Center for Laser Research (NCLR), a spin-off of the Chair Laser Physics and Non-linear Optics at the University Twente, has developed a 1kW excimer laser. The company is now developing the process of drilling holes in airframe sections and aero-engine components. The quality of holes drilled with this laser is superior to the quality of holes drilled by pulsed Nd:YAG lasers. The company is working with experts at Pratt & Whitney (East Hartford, CT) to introduce this laser in the production of components for the engines of the Raptor Joint Strike Fighter.
Several organizations arrange meetings to inform interested companies about the advantages of laser materials processing and about new developments. These include Bond voor Materiaalkunde (Union for Material Science), Vereniging voor Productietechniek (Union for Production Technology), Nederlands Las Instituut (Dutch Welding Institute), and Mikrocentrum. The laser system suppliers normally train equipment operators. Education institutes with laser material processing-related items in their program are: Leidse Instrumentmakers School (Leiden), a school for fine mechanical engineers; HTS Rijswijk, a technical college (Rijswijk); the Technical University Delft; and the Universities Twente and Groningen.
Martien H.H. van Dijk, an industry consultant on lasers and laser processing, is a valuable contributor to ILS. He can be contacted by e-mail at [email protected].