Bulk Metallic Glasses
Bulk metallic glasses manufactured by selective laser melting
Today, complex alloy compositions allow the production of amorphous metal alloys with low critical cooling rates in relatively big dimensions by chill casting. These so called bulk metallic glasses feature a high compressive strength as well as elastic deformation. The production of bulk metallic glasses by selective laser melting allows the construction of complex geometries and provides the prospect of overcoming size restrictions, which inevitably arise in a chill casting process on account of critical cooling rates. Functional properties can be improved in a subsequent micro structuring process. In cooperation with the Institute of Complex Materials (IKM) of the Leibniz Institute for Solid State and Materials Research Dresden (IFW) and the Institute of Production Science (wbk) of the Karlsruhe Institute of Technology (KIT), the project is focused on an analysis of the influence of all process parameters involved in the production and surface structuring of bulk metallic glasses, as well as their microstructure and mechanical behavior. The aim is to get detailed information on characteristic process-microstructure-property-correlations. Another aim is the development of an efficient rapid test to detect crystalline areas resulting from the surface machining process.
The investigations are conducted on two amorphous metal alloys: the Zr-based alloy Vitreloy 105, with good glass forming ability, and a Fe-based alloy with extremely high compressive strength and good soft magnetic properties. Surfaces of the specimens are machined by different structuring methods, including micro milling, electrical discharge and micro laser machining (see figure below). Subsequently, surfaces are treated by abrasive blasting and shot peening. The influence of a particular structuring method on the near-surface microstructure is analyzed within a full metallographic characterization. Quasistatic and fatigue testing provide information on the mechanical behavior of the material.
 Schulze, V.; Hoppen, P.; Ruhs, C.; Weber, P.: Micro structuring of Zr-based bulk metallic glasses. Proceedings of the 9th international conference on Multi-Material Micro Manufacture, 4M Association, Wien 2012, S. 144-147
Ansprechpartner: Dipl.-Ing. Daniel Grell