EMO 2019 Ausgabe 2

••• 18••• Innovationen Joining materials with more design variety One-step, 3D printing for multimaterial projects developed by Washington State University researchers S imilar to the advance from black and white to colour printing, a Washington State Uni- versity research team for the first time has used 3D printing technol- ogy in a one-step process to print structures made of two different materials. The advance could help manufacturers reduce manu- facturing steps and use one ma- chine to make complex products with multiple parts in one opera- tion. Until now, 3D printing, also known as additive manufacturing, has been limited to using mostly one material at a time. Led by Amit Bandyopadhyay, School of Mechanical and Materi- als Engineering, the researchers used 3D printing technology to print out metal and ceramic struc- tures as well as a bimetallic tube that is magnetic in one end and nonmagnetic in the other. Three-dimensional printing has changed the landscapes of many industrial practices and has sig- nificantly influenced product design protocols. Anyone who wants a custom part can design it on a computer and then simply print it out. However, manufac- turers can only put one material into a printer to print out parts. By being able to use more than one material at a time, they will be able to better control prop- erties like heat conduction, cor- rosion protection, as well as en- vironmental adaptation in their materials. “This is a step towards the next level of manufacturing and the next generation of de- sign, validation, optimisation and manufacturing using 3D print- ing,” said Bandyopadhyay. With adoption of multimaterial, 3D printing, manufacturers also won’t need to use the adhesives or joint connections that are now required for creating multimateri- al products. “You could be joining two very strong materials togeth- er, but their connection will only be as strong as their adhesive,” said Bandyopadhyay. “Multimate- rial, additive manufacturing helps get rid of the weak point.” The researchers used a laser- based 3D printer to join the mate- rials in a single step, printing out a nickel-chromium and copper structure. Inconel 718 is a nickel- chromium alloy used in liquid- fueled rockets and for sheet met- al parts for airplane engines. The material can withstand high tem- peratures, but it cools very slowly. When the researchers added the copper in the 3D printing process, the part could be cooled 250 per cent faster, meaning a longer life and higher fuel efficiency for air- plane engines. Multimaterial 3D printed designs allow for greater design variety and specificity. Photo: WSU