Metal hook and loop fastener, tougher than Velcro
German university invents uber-Velcro, lifts tons, resists heat, chemicals.
Velcro's great, but for when you need that extra hold, there's a new hook and loop fastener made from spring steel in Germany that can pinch together loads of up to 35 metric tons, according to researchers.
The uber-Velcro, dubbed Metaklett, is also chemical-resistant and can withstand temperatures of nearly 1,500 degrees Fahrenheit, according to developers at the Institute of Metal Forming and Casting, Technical University Munich (TUM).
Although Velcro and its knockoffs have been used on everything from shoes to space shuttles since its invention by Swiss engineer George de Mestral 60 years ago, it has limitations. Weak spots include hospitals, where aggressive disinfectants are used, and the construction and auto industries. "Temperatures of several hundred degrees centigrade can arise around the exhaust manifold," said lead scientist Josef Mair, explaining why a garden variety synthetic hook and loop will not do in some situations.
After testing, the institute settled on two variations--the "Flamingo" and "Entenknopf" (or duck's head) models. Both start out as less than one inch thick metal tape, but the Entenknopf uses fine steel hooks and loops, while the Flamingo uses wider hooks that snap into openings in the tape. "They are bent in such a way that they deform elastically under light pressure and glide into the holes like the synthetic buckles on backpack straps. Once inserted, they return immediately to their original form and, thanks to their sprung splaying arms, they resist back-pull like an expanding rivet," the literature explains (PDF).
"The animal names arose as a way of differentiating between the multifaceted models. The hook forms of the two systems are vaguely reminiscent of a duck's head and a flamingo standing on one leg," Mair said. Metaklett is a portmanteau of Metall and Klettverschluss, which is the German generic for Velcro.
And what of that iconic scratch Velcro makes as it is undone? The sound of Metaklett being unzipped has been described as "metallic, like a glittering chain," TUM's Patrick Regan said. Sounds like an improvement.