Nov_Dec_AMP_Digital

A D V A N C E D M A T E R I A L S & P R O C E S S E S | N O V E M B E R / D E C E M B E R 2 0 2 0 8 METALS | POLYMERS | CERAMICS Tooling Tech Group (TTG), Macomb, Mich., completed a 21,000-sq-ft expansion at its Washington, Mo., location, one of three TTG facilities focused on die cast tooling, aerospace tooling, precision machining, and die repair capabilities. The facility now has 61,000 sq ft and features two new 60-ton bridge cranes and a large double column bridge mill with a 70,000 lb capacity. toolingtechgroup. Ball Corp., Broomfield, Colo., will invest $300 million in a new aluminum beverage packaging plant in Pittston, Pa., expected to be operational in mid-2021. The plant will produce aluminum packaging to serve demand in the sparkling water, spiked seltzer, beer, and carbonated beverage markets. ball.com . BRIEFS glass transition temperature. In these calculations, binary particle mixtures were modeled with finite-range repul- sive potentials. The team found that the strength of amorphous materials is an emergent property caused by the self-organization of the disordered me- chanical architecture. www.u-tokyo. ac.jp/en. NEW ELASTOMERS FOR BIOMATERIALS Bioengineers from Cornell Univer- sity, Ithaca, N.Y., are designing elasto- mers for medical use that integrate iron and calcium. They developed a new framework that makes elastomer de- sign a modular process, allowing for the mixing andmatching of different metals with a single polymer. The framework was conceived when researchers from Cornell’s Biofoundry Lab sought to cre- ate an elastic vascular graft that could help repair heart tissue using copper due to its role in inducing angiogenesis. The team’s key breakthrough was crosslinking the polymer with copper ions using chelating ligands. Because one ligand can bind multiple metal ions, it can yield a wide range of me- chanical and biomedical properties. As proof of concept, researcher Ying Chen engineered six unique elastomers using one polymer and six different metals, and then made a seventh elastomer using a calcium-magnesium mix. It was the first time anyone had demonstrated a biodegradable metal-ion elastomer— let alone seven of them. The research team also performed mechanical and Computer simulations are used to study the rigidity of amorphous solids like glass. Courtesy of Institute of Industrial Science, University of Tokyo. UNDERSTANDING GLASS RIGIDITY Scientists at The University of To- kyo are working to better understand amorphous solids from a mechanical perspective. The researchers employed a new computer model to simulate the networks of force-carrying parti- cles that give these solids their strength even though they lack long range order. This work may lead to new advances in high-strength glass, which can be used for cooking, industrial, and smartphone applications. Amorphous solids such as glass—despite being brittle and having constituent particles that do not form ordered lattic- es—can possess surprising strength and rigidity. This is even more unexpected because amorphous sys- tems also suffer from large anharmonic fluctuations. The secret is an internal network of force-bearing particles that span the entire solid, lending strength to the system. This branching, dynam- ic network acts like a skeleton that prevents the material from yielding to stress even though it makes up only a small fraction of the total particles. However, this network only forms af- ter a “percolation transition” when the number of force-bearing particles ex- ceeds a critical threshold. As the density of these particles increases, the proba- bility that a percolating network that goes from one end to the other increas- es from zero to almost certain. The researchers used computer simulations to carefully show the forma- tion of these percolating networks as an amorphous material is cooled below its