Press

The phenomenon of so-called superlubricity is known, but so far the explanation at the atomic level has been missing: for example, how does extremely low friction occur in bearings? Researchers from the Fraunhofer Institutes IWM and IWS jointly deciphered a universal mechanism of superlubricity for certain diamond-like carbon layers in combination with organic lubricants. Based on this knowledge, it is now possible to formulate design rules for supra lubricating layer-lubricant combinations. The results are presented in an article in Nature Communications, volume 10.

To ensure the digital networking of production systems and the optimization of material-specific requirements, we need to measure, analyze and replicate the changes in material properties in a process in which “digital twins” of materials are created. The materials data space developed by Fraunhofer researchers has laid the groundwork for this process.

Permanent magnets used in electric cars and wind turbines currently contain rare earth metals. Reducing the amount of these elements in magnets is important, as mining them is harmful both to health and the environment. Researchers have now developed a new machine learning tool to assist in quickly and easily predicting the ferromagnetic crystal properties of novel material compositions.

High-strength steels play a vital role in the construction of modern vehicles and machines. If these steels are welded during the production of components, mobile hydrogen atoms can cause problems within the material: the atoms accumulate slowly at highly stressed areas of a component, resulting in the steel becoming brittle at these locations. This can result in so-called cold break formations which can lead to component failure. Dr. Frank Schweizer of the Fraunhofer Institute for Mechanics of Materials IWM has developed a simulation method with which component manufacturers can assess cold break tendencies and adjust their production accordingly.

Diamond coatings help reduce friction and wear on tools, bearings, and seals. Lubricating diamond with water considerably lowers friction. The reasons for this are not yet fully understood. The Fraunhofer Institute for Material Mechanics IWM in Freiburg and the Physics Institute at the University of Freiburg have discovered a new explanation for the friction behavior of diamond surfaces under the influence of water. One major finding: in addition to the known role played by passivation of the surfaces via water-splitting, an aromatic passivation via Pandey reconstruction can occur. The results have been published in the journal Physical Review Letters.

To reduce process costs in industrial parts manufacturing while simultaneously improving quality, the use of diamond-coated, cemented carbide cutting tools has increased. Adhesion of diamond coatings was previously problematic, particularly when processing composite or lightweight materials. Suitable pretreatment is therefore vital. Dr. Manuel Mee of the Fraunhofer Institute for Mechanics of Materials IWM has developed a new pretreatment routine that increases the adhesion of CVD diamond to carbide: by combining several approaches into a single process, all factors which affect the adhesion of the coating can be taken into consideration, leading to a fundamental improvement of the adhesion.

(July 17, 2017) Materials for light construction and high-temperature applications first have to be qualified before use in order to be able to utilize them to their full potential. The fatigue tests necessary for this purpose can now be performed with a newly developed optical strain measurement system with significantly faster test frequencies without the use of conventional, contacting measurement systems which lead to unwanted damage to test specimens. The versatile process developed by the Fraunhofer IWM and IPM combines the advantages of previous optical and mechanical measuring methods.

(July 4, 2017) Sheet metal materials are often stressed to their limits during the forming process. Computer simulations are used to test how far it is possible to go in the production stage. However, the simulations are only as exact as the data upon which they’re based. A team at the Fraunhofer Institute for Mechanics of Materials IWM in Freiburg has now developed a virtual test laboratory that allows for the examination of metal materials at different load states and for the determination of precise mechanical data.

(May 4, 2017) A new technique, developed by the Fraunhofer Institute for Mechanics of Materials IWM, makes it possible to bend sheet glass into complex or unconventional shapes with the help of laser beams. This technique opens up a whole new range of potential products for architects and designers. The researchers are taking advantage of a particular attribute glass has of becoming viscous and therefore malleable when exposed to high temperatures. Gravity and precise calculations do the rest.

(December 21, 2016) As the most important industrial construction material, with more than 2,500 grades, steel is highly specialized for diverse applications. Even the smallest changes of the composition can modify the material structure on an atomic scale and improve material properties on the macroscale. The consortium of the EU-project Z-Ultra, led by the Fraunhofer Institute for Mechanics of Materials IWM, has developed new 12% chromium alloys for high-temperature applications that are up to 30% stronger than traditional 9% chromium steels and withstand higher temperatures and pressures for a longer period of time. Atomistic simulations supported the development of the new steel alloys in a targeted manner.