A self-healing system for concrete developed in Europe was inspired by a Dutch researcher’s trip to Yellowstone National Park in Wyoming. As concrete ages, water seeps into cracks, which widen as the water freezes and thaws. In the new approach, specific organic mineral precursor compounds plus spore-forming alkaliphilic bacteria are incorporated into concrete during the manufacturing process. They produce calcite particles up to 100-μm in size that are shown to seal micro- to even larger-sized cracks. Erik Schlangen, a professor at Delft Technical University in The Netherlands said he got the idea after seeing deposits of calcite near geysers at Yellowstone. The improvement in crack resistance is said to more than compensate for a 10 percent loss in compressive strength due to incorporation of the bacteria, says Schlangen. The approach will also reduce the amount of raw materials used in concrete.
Last week, the bill for reforming chemical regulation, the TSCA Modernization Act of 2015, passed the House. If it or a similar bill becomes law, the effects on cost and availability of adhesives and plastics incorporating these substances are not yet clear.
The latest crop of coating and sealant materials and devices has impressive credentials. Many are designed for tough environments with broad operating temperature ranges, and they often cure faster, require fewer process steps, and produce less waste.
A new program has been proposed for testing and certify 3D printing filaments for emissions safety. To engineers who've used 3D printers at home this is a no-brainer. It's from a consumer on Kickstarter, and targets use in homes and schools.
For the last 50 years, the Metal Powder Industries Federation (MPIF) has sponsored an awards competition for creative solutions to designing and fabricating near-net-shape parts using powder metal (PM) technologies. Here are the seven Grand Prize winners of the 2015 contest.
Graphene 3D Lab has added graphene to 3DP PLA filament to strengthen the material and add conductivity to prints made with it. The material can be used to 3D print conductive traces embedded in 3D-printed parts for electronics, as well as capacitive touch sensors.
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