November/December 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 1 8 8 METALS | POLYMERS | CERAMICS Nucor Corp., Charlotte, N.C., is in- vesting $650 million to greatly in- crease capacity at its Nucor Steel Gallatin plant in Kentucky. Nucor expects to expand the plant’s rolled-steel capacity from its cur- rent 160,000 tons to an estimated 300,000. The expansion will create 70 new jobs and will allow the company to produce rolled sheets up to 73 in. wide. nucor.com . Ellwood Group, Ellwood City, Pa., plans to build a $60 million aluminum casting plant at the company’s Ellwood Engineered Castings site in Hub- bard, Ohio. The 70,000-sq-ft building is projected to produce roughly 150 million pounds of large round billets and slabs. The facility is expected to open in early 2020. ellwoodgroup.com . BRIEFS “Our experiments show that the MoSiBTiC alloy is extremely strong com- pared with cutting-edge nickel-base single crystal superalloys,” says lead re- searcher Kyosuke Yoshimi. Creep behavior is an important factor because increased temperature and pressure leads to creep deforma- tion. Understanding the material’s creep can help engineers construct ef- ficient heat engines that can withstand extreme temperature environments. Researchers assessed the alloy’s creep in a stress range of 100-300 MPa for 400 hours. All experiments were performed in a computer-controlled test rig under vacuum in order to prevent the mate- rial from oxidizing. Further, the team reports that the alloy experiences larg- er elongation with decreasing forces. Thus far, this behavior has only been observed with superplastic materials capable of withstanding unexpected premature failure. Schematic of the atom hybridization method. Five metal elements are blended in a small cluster on a 1-nm scale. MULTIMETALLIC CLUSTER BREAKTHROUGH Multimetallic clusters are gain- ing momentum in materials science as they exhibit properties that cannot be attained by single-metal materials. A team from the Tokyo Institute of Tech- nology developed an atom hybridiza- tion method, which has realized the first-ever synthesis of multimetallic clusters consisting of more than five metal elements with precise control of size and composition. The method em- ploys a dendrimer template that serves as a tiny scaffold to enable controlled accumulation of metal salts. After precise uptake of the dif- ferent metals into the dendrimer, multimetallic clusters are obtained by chemical reduction. The team suc- cessfully demonstrated the formation of five-element clusters composed of gallium, indium, gold, bismuth, and tin, as well as iron, palladium, rhodium, antimony, and copper, and a six-ele- ment cluster consisting of gallium, in- dium, gold, bismuth, tin, and platinum. The team also hopes to make clusters composed of eight metals or more. www.titech.ac.jp . METAL ALLOY STANDS UP TO ULTRAHIGH TEMPS AND PRESSURE New research coming out of To- hoku University, Japan, reports a TiC-reinforced, Mo-Si-B-base alloy (MoSiBTiC) able to stand up to constant forces in ultrahigh temperature, offer- ing promising applications in aircraft jet engines and gas turbines for electric power generation. The performance of heat engines is key to future fossil fuel energy harvesting and the subsequent conversion to electric power and pro- pulsion force. The enhancement of their functionality may determine how efficient they are at energy conversion. 3D SEMmicrostructure of a first genera- tion MoSiBTiC alloy. Courtesy of Kyosuke Yoshimi.