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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 | M A Y / J U N E 2 0 1 9 8 METALS | POLYMERS | CERAMICS Kaman Composites Wichita (KCW), Kan., a division of Kaman Aerosystems, was award- ed the manufacture and supply of composite skin to core assembly structural components for the Bell AH-1Z helicopter blades. Bell Helicopters, Fort Worth, Texas, has produced the AH-1Z for the U.S. Marine Corps (USMC) at their Amarillo, Texas, manufactur- ing facility since 2003. All compos- ite detail parts and assemblies will now be manufactured at the KCW facility. kaman.com . Allegheny Technologies Inc. (ATI), Pittsburgh, extended its long-term purchase agreement (LTPA) with Rolls-Royce, U.K., to supply rotating disc quality specialty materials for their Trent engine family. The LTPA extends the Rolls-Royce/ATI agreement through 2029. atimetals.com. BRIEFS lower cost of zinc oxide compared to germania all make the new glass com- position a practical choice for mass- scale manufacturing, according to the researchers. psu.edu . NEW ALLOYS HOLD PROMISE FOR PLUMBING The use of lead in water valves and plumbing systems for more than 10 million U.S. homes is a great health concern. A team of researchers from Purdue University, West Lafayette, Ind., investigated alternative lead-free bronze alloys for use in these systems and found new copper-manganese al- loys with diverse applications that may reach beyond water safety and plumb- ing. The new Cu-Mn alloys have higher strength and better castability com- pared to other lead-free alternatives. Plumbing fitting and valve manu- facturers traditionally use small addi- tions of lead to improve machinability of the bronze alloys and to plug the continuous shrinkage porosity that de- velops due to their wide freezing range in casting. Those manufacturers have spent the past decade trying to find lead substitutes such as bismuth that are easy to use and affordable. “These alloys solidify over a very narrow temperature range, are com- pletely free of microscopic shrinkage porosity, and have higher strength, so thinner-walled castings can be used compared to their counterparts,” says lead researcher Kevin Trumble. “We have proven their effectiveness as feasi- ble, cost-effective alternatives for water Glass being trimmed from a crucible. Courtesy of Penn State. COMPOSITE GLASS FAMILY SUITS OPTICS Researchers from Penn State Uni- versity, State College, recently discov- ered a novel glass family. The new com- position of germanosilicate glass, creat- ed by adding zinc oxide, contains prop- erties optimal for lens applications. Germanosilicate glass is es- sential in the manufacture of optical amplifiers, wave- guides, and solid-state la- sers. The new family of zinc germanosilicate glass has a high refractive index com- parable to that of pure ger- mania glass. The samples also show high transparen- cy, good ultra-violet-shield- ing properties, and good glass forming ability, all of which make them suitable for lens applications. With glass, the refractive index de- termines its use, but achieving a high refractive index has its challenges. The researchers avoided issues such as crystallization and high opacity by find- ing the optimum balance of zinc oxide with the other components of the glass composition. Zinc oxide also exhibited UV shielding properties in the team’s samples. With UV shielding, a zinc ox- ide-containing glass could be used for everyday applications such as car win- dows or eyeglasses. “The benefit of a high refrac- tive index is its capacity for designing low-thickness lenses,” says Ye Luo, a doctoral student in materials science and engineering. The samples also showed favor- able forming properties. As a long glass, the new compositions can be formed over a broader temperature range, making them much simpler to manip- ulate during formation. This property, resistance to crystallization, and the Bell USMC AH-1Z Viper. Courtesy of Wikime- dia Commons/Gerry Metzler.