Interesting bit of reporting here on MIT News about metamaterials whose negative refractive index means they shrink instead of expand as is typical when objects are heated. Researchers at MIT 3D-printed some objects – à la Hoberman spheres – and recognized they shrunk “one part in a thousand, or about 0.6 percent.”
Almost all solid materials, from rubber and glass to granite and steel, inevitably expand when heated. Only in very rare instances do certain materials buck this thermodynamic trend and shrink with heat. For instance, cold water will contract when heated between 0 and 4 degrees Celsius, before expanding.
Engineers from MIT, the University of Southern California, and elsewhere are now adding to this curious class of heat-shrinking materials. The team, led by Nicholas X. Fang, an associate professor of mechanical engineering at MIT, has manufactured tiny, star-shaped structures out of interconnected beams, or trusses. The structures, each about the size of a sugar cube, quickly shrink when heated to about 540 degrees Fahrenheit (282 C).
Watch the video:
Have an amazing project to share? Join the SHOW-AND-TELL every Wednesday night at 7:30pm ET on Google+ Hangouts.
Join us every Wednesday night at 8pm ET for Ask an Engineer!
Learn resistor values with Mho’s Resistance or get the best electronics calculator for engineers “Circuit Playground” – Adafruit’s Apps!
Maker Business — Adafruit interviews Dan Rasure, Managing Partner TechShop 2.0
Wearables — Simulate tattoos
Electronics — Heatsinks aren’t enough!
Biohacking — Getting More from Home DNA Testing
No comments yet.
Sorry, the comment form is closed at this time.