Lower size limit set by resolution
Ercolano printed David in two sizes: first as a sculpture just 1 millimeter high, and then one ten times smaller. “The smaller figure is only as tall as the pedestal of the larger one,” he says. But with structures that small, achieving the required resolution becomes problematic. Printed metallic micro-objects typically starts at 1 micrometer (µm), and for more complex and detailed objects, sizes range from 100 µm to 1 mm. In terms of time, too, the 1 mm model is a world away from the one that is ten times smaller: the device needed 30 hours to create the “big” David but just 20 minutes for the smaller version.
Theoretically, the system can print objects up to 5 mm in size, but the printer cartridge contains only a microliter of “ink” – just about enough for manufacturing the larger David. But it is also enough “ink” to print hundreds or even thousands of tiny objects, which represents the real strength of the process. The principle works
Zambelli is very pleased with the result. “We’re thrilled that a technology from our research lab has made its way into practical application,” the ETH professor says, continuing: “An independent group was able to adopt our 3D printing technology and even improve upon it – which shows that it really works.”
The printing process is of interest first and foremost to the electronics industry. With this method, manufacturers could connect computer chips together or precisely repair microelectronics systems. Although other metals can be printed, such as platinum, gold, nickel or silver, copper is in highest demand. “Nine out of ten enquiries are about copper,” Ercolano says.
This project is supported by Innosuisse, the Swiss Innovation Agency.
