At the Automate 2019 fair in Chicago, metal powder specialist Heraeus presented a world record additive manufactured gear wheel made of amorphous metals (also known as metallic glass or glassy metal). The gear wheel was 3D printed in a standard SLM system with material from Heraeus. With this world premiere, Heraeus is breaking through the boundaries of 3D printing and opening completely new design possibilities for a wide range of industries – from automation solutions and robotics to aviation, medical technology and the automotive industry.
An amorphous metal is a solid metallic material, usually an alloy, with disordered atomic-scale structure. Most metals are crystalline in their solid state, which means they have a highly ordered arrangement of atoms. Amorphous metals are non-crystalline and have a glass-like structure. But unlike common glasses, such as window glass, which are typically electrical insulators, amorphous metals have good electrical conductivity.
New design possibilities and applications
The gear wheel printed by Heraeus eclipses all previous results. Produced by additive manufacturing, this compact machine part weighs two kilograms. Due to the required high cooling rates of mainly over 1000 Kelvin/second, only small parts could be produced from amorphous metals previously. Because the topology of the gear was also optimized during development, material and process experts were able to reduce the weight by 50 percent compared to conventionally manufactured versions. Heraeus has now redefined the existing limits of technology in terms of size and complexity, revolutionizing design possibilities, for example, in the automation industry as well as in robotics. The metal powder company set this world record using a commercially available laser melt printer.
Because of their non-crystalline structure, amorphous metals combine properties within one material that normally are not feasible, such as extreme hardness and high yield strength with high elasticity. Amorphous metals are also characterized by good corrosion resistance, excellent wear resistance and the elasticity of polymers. They have soft magnetic properties and are easy to magnetize and demagnetize. With this combination of properties, amorphous metals are superior to steel, titanium and many other materials.
Reduced weight with precision manufacturing
High-precision layer-by-layer production with special materials from Heraeus also reduces material usage, saving weight and costs. Using 3D printing also reduces overall production costs. With conventional methods, making complex parts require numerous process and manufacturing steps. Several individual pieces have to be produced and then assembled into a unit. However, 3D printers accomplish this in a single process. Following assembly in the printer, moving parts are immediately ready for use and fully functional.