A new technology expands the lifetime of components.
The lightweight material magnesium suffers from poor resistance to corrosion and a high degree of softness. Thanks to a new innovative procedure, parts made of magnesium and other metals can be protected from corrosion and wear in precise locations. The procedure uses lasers to melt the high-performance plastic material PEEK onto the surface. This unique trick allows the laser to be used to only apply the protective plastic layer to those sections of the component that are under additional stress and need special protection. Initial tests have shown that the applied layer can result in a part that withstands friction wear 100 times longer than an untreated part. The new process was developed by researchers at Eloxalwerk Ludwigsburg Helmut Zerrer GmbH and the Fraunhofer Institute for Laser Technology ILT.
The Development Agency for Lightweighting Baden-Württemberg is presenting this innovation as its ThinKing for June 2018. Leichtbau BW GmbH awards this distinction each month to offer a platform to innovative products and services in the Baden-Württemberg lightweighting sector.
The new coating technology can be used for example for movable parts in motors, transmissions or bearings – everywhere where the components must withstand high temperatures and friction should be kept to a minimum in order to prevent wear. For the treatment of a component with a protective layer of the high-performance plastic PEEK (poly ether ketone), the plastic is first blended with additives and precisely placed in the desired spot. Then two laser beams are used to ensure that the PEEK is melted onto the treated area. This process produces an extremely thin and highly durable plastic surface layer which protects the base material from corrosion and wear.
The new process offers several other benefits as well. “By targeting the use of the laser at a certain area, the heat stress placed on the component is kept as low as possible,” explains Jörg Zerrer, managing director of ELB – Eloxalwerk Ludwigsburg Helmut Zerrer GmbH. In addition, the procedure is resource efficient since the targeted application does not allow any material to be “lost”, as it is often the case if protective layers are applied through spraying procedures. “We also do not use any solvents that are harmful to the environment,” ensures Jörg Zerrer.
High durability of the protective layer
Initial technical tests have shown the potential of the new layering process. The so called pin-on-disc test examines how the protective layer performs when subjected to friction and wear. In this test, a steel ball is pressed onto a rotating disc that has been treated with the protective layer to determine how much ongoing performance the material can withstand before showing signs of wear. “Compared to other systems available on the market, we can reduce the wear to such a degree that our new protective layer can increase the lifespan by 100 times. The reduced friction enables an increase in energy efficiency during the operation of moving parts of motor components or bearings,” explains Jörg Zerrer. This enables the production of nearly maintenance free drive systems, notes Zerrer. “This new process opens up new areas of application for lightweight materials such as magnesium or aluminum,” says Dr. Wolfgang Seeliger, managing director of Leichtbau BW GmbH. More information at: www.ceranod.de