Rapid Protocasting

Today was, among many reasons, an excellent day. After hardly sleeping, I awoke strikingly early to a warm spring morning, and had an early meeting with Hugh Herr, leader of the biomechatronics group over at the MIT Media Lab, where we talked about some work I could do for him that might be of some mutual interest. I then immediately picked up some books for my American Revolution course, skimmed the relevant passages, and felt I knew enough to head to class.

And then promptly skipped the first half hour to do something AMAZING. I’m taking 3.042 this term, a course focused on working an independent project as if you were an internal project in a company. The project I’m working on is using 3D printed concrete to create molds for metal casting. The problem, which you will see after thinking for a few, is that concrete melts at the temperatures of molten steel or other alloys. This makes molding less of a useful thing and more of an exercise in futility.

Nonetheless, I skipped class to do the first step of our experiment for the day; a real live steel pour. The tech my team is developing, see, is a ceramic slurry which can be slip cast onto the concrete mold. As the slurry is poured into the mold, the concrete sucks out the liquid, pulling the ceramic particles in the slurry onto the surface of the concrete. Once a thick enough layer is built, the remainder of the slurry is poured out of the mold, leaving a thin particulate ceramic covering the mold. Firing the baby in a furnace sinters the ceramic, and a beautiful, thin, hard, high temperature coating is left on the mold. I did this for about 6 different test pieces, using different soak times in the slurry to build different layer thickness, leaving several nice looking molds with our most successful ceramic layer to date on the surface.

I went to the rest of my classes and the magical hour of two finally came, when 3.042 starts and we could finish our experiment. Now that we had a few sample molds with high temperature coatings, we did the only thing you can do with such a trite object, which is pour many pounds of 1600 degree Celsius brilliantly bright steel into them and pray the molds don’t explode. The pour went fairly brilliantly, and we should have fairly good baseline data to push our experimental exploration in a solid direction. All things considered, an ace day for an ace project.

Stay tuned, soon we’ll be CADing up all kinds of crazy shit just to make molds and cast it in various high temperature alloys. Flywheels, hands, pretzels, whatever we can think of, we’re going to cast it and see what happens! Whoo, Science! No, not quite, ENGINEERING!

Till then,

Cody Daniel