The IEEE International Magnetic Conference INTERMAG 2014 will be held at the International Congress Center in Dresden in cooperation with the Leibniz Institute for Solid State and Materials Research Dresden (IFW Dresden). After Amsterdam in 2002 and Madrid in 2008, this year Dresden will be the place for this high-calibre conference. Hanau-based VACUUMSCHMELZE GmbH & Co. KG will attend the conference, held from 4th - 8th May, and will participate by having a stand / booth and presenting a paper. VACUUMSCHMELZE focuses on materials and technologies that streamline efficiency – a focus that will be reflected in Michael Weickhmann's talk. Scheduled for 6th May as part of the “Motors and Generators” Symposium, the talk will be entitled “Shifting the limits with high end magnetic materials and technologies”
In Dresden, VAC will present their complete portfolio of magnetic materials for electric motor applications from its Materials & Parts and Permanent Magnets divisions. VAC's expertise pushes the limits of conventional materials, offering products beyond electrical steel sheets in thicknesses from 0.35 to 0.5 mm or non-segmented rare-earth magnets and supplying all processes and products – from melting to finished laminated stacks or magnetic systems – from a single source.
The company's NiFe alloys feature minimum iron losses thanks to their low coercivity and high electrical resistance. An excellent example of such alloys is ULTRAVAC® 44 V6, used in the construction of the electrical motors of the Solar Impulse aircraft and largely responsible for the overall efficiency of 98 per cent.
The limitations of NiFe materials with respect to induction levels are overcome by using the CoFe alloys VACOFLUX® and VACODUR®, which have significantly higher saturation polarization of up to 2.3T, together with considerably lower losses than electrical steel.
In addition to the materials used, the production method used for manufacturing the laminated core stacks has a critical influence on the resulting iron losses. VACSTACK ® technology enables ultra-thin metal sheets (e.g. 55µm) to be used as an efficient method of reducing eddy current losses. Despite the thinness of the sheets, packing densities of 98% can typically be achieved, with outstanding insulation between the strip layers.
Eddy currents in permanent magnets can also be reduced by segmenting the magnets. The segmented neodymium-iron-boron (NdFeB) VACODYM® magnets from the Hanau-based company are among the most powerful in the world and benefit from minimum insulation thicknesses between the magnets, thanks to VAC's tailored processes. In addition, VAC is the only company to supply finished laminated rotor core stacks incorporating glued permanent magnets for immediate installation.
A further highlight is VACCOAT® 30033. Developed in-house by the company, this new heat-cured finish in green enables improved insulation between VAC's rare-earth permanent magnets, especially under extreme conditions. The protective coating is designed for continuous use at temperatures of up to approximately 200°C and can withstand peak temperatures up to 250°C for periods of several hours. The new spray-on coating also features superior corrosion resistance to its predecessor.