The range of metals that can be 3D printed is increasing quickly. ExOne has added iron infiltrated with bronze (shown here) and bonded tungsten to the range of metal and ceramic powders that can be used with its multi-material M-Flex machines. (Source: ExOne)
Both metal and sand printing processes are described here http://exone.com/materialization/what-is-digital-part-materialization/explanation-technology The metal process uses a print head that distributes the binder into beds of specially formulated materials. It is then sintered in an oven. A secondary process may also be applied to reach near-100% density. This page also has videos demonstrating the process.
78RPM, one of ExOne's customers might be looking into a ceramic engine--or more likely, certain engine parts in ceramics, most likely ceramic matrix composites. GE Aviation is already doing this in turbine nozzles: http://www.designnews.com/author.asp?section_id=1392&doc_id=264282&page_number=2
I wonder if the company is looking into the possibility of finally creating a ceramic engine. Internal combustion engines attain greater efficiency at high temperatures. But materials limit the temperature permitted. Is it possible that 3D printing could pemit creation of a practical ceramic engine?
Ann, this is interesting, but how does the strength of these printed metal parts compare with forged parts, or with polymers? The reason I ask is that in some manufacturing areas the introduction of Metal Injection Molding (MIM) parts has caused concern. Typically these parts are not as strong as forged or machined parts. They are used where that level of strength is not required. I would think that printed metal parts would fit into this range as well.
Most of the new 3D printers and 3D printing technologies in this crop are breaking some boundaries, whether it's build volume-per-dollar ratios, multimaterials printing techniques, or new materials types.
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