There are complete 3D printing systems that print in solid metal, but they are frighteningly expensive. There have been some developments in lower cost open source metal 3D printers that we've previously reported, but difficulties remain.
Even if you solve the printing problems, you’re still left with a big issue: removing prints from the substrate typically requires access to pricey metal cutting equipment not typically found in home workshops.
The researchers, from Michigan Technological University, developed techniques to overcome this. They explain in their research paper:
This article investigates several substrate treatments to provide a low-cost method to easily remove 3D-printed 1100 aluminum parts from a reusable substrate. Coatings of aluminum oxide and boron nitride on 1100 aluminum and A36 low-carbon steel substrates were tested. Lap shear tests were performed to assess the interlayer adhesion between the printed metal part and the print substrate. No warping of the substrate was observed during printing.
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