New Class of Metallic Glasses
After several years of research, Alexander Kuball, Benedikt Bochtler and Oliver Gross, doctoral candidates at the Chair of Metallic Materials, which is led by Professor Ralf Busch, have developed very strong yet lightweight alloys in collaboration with technology group Heraeus. Compared to previous materials from the class of amorphous metals, these alloys have crucial advantages: the compounds consist mainly of titanium and sulphur and hence consist of elements that are abundant on earth and excellent for industrial use. In addition, unlike amorphous metals based on zirconium, palladium or platinum, titanium is relatively inexpensive, like sulphur. Titanium also has no highly toxic effect, unlike the elements beryllium and phosphorus, which have been frequently used up to now. The alloys the researchers developed are almost twice as strong as conventional titanium-based metals of the same density, i.e., the same weight, making these so-called metallic glasses suitable for the production of small, lightweight components for the aerospace industry, for example.
The process by which the researchers produce the alloy is essential for its properties. The melt, which has a temperature of over 1,100°C, is cooled instantaneously, causing the alloy to solidify into a disorderly atomic structure. Due to its disorderly structure, this alloy has completely different properties than conventional alloys of the same starting materials: the metallic glasses are as strong as steel, but as elastic as plastic.