Glad you found it valuable shehan. And thanks for the Loughborough U video. We've touched on 3D printing buildings and 3D printing with concrete a few times in DN, such as the D-Shape http://www.designnews.com/author.asp?section_id=1394&doc_id=261796 but I wasn't aware of LU's work. Most of ours have been about technologies aimed at building structures in space, like this one: http://www.designnews.com/author.asp?section_id=1392&doc_id=267732
As for where the power comes from, either we bring it along or capture it on site. The challenge being that it takes a fair amount of power to heat metal enough to bond into a monolithic mass. And of course the lack of gravity makes powders harder to handle. Perhaps adding a fluidic binder to the metal powder would be the solution. It could also serve as a flux to assist the bonding process.
William's got a point. Even though I like to say that technology problems can be solved with enough dollars and brains thrown at them, I know that's not always the case. Especially not when the laws of physics are the technology barrier. OTOH, the semiconductor industry has been truly innovative in finding ways to cope with those laws, again and again, over several decades, coming up with all kinds of new materials and processes along the way. OTOOH, they've had more money than other industries. Way, way more.
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