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news & trends A simulation shows the dance between two black holes before they merge into one, an event that created gravitational waves that scientists on earth have detected for the first time. incredibly small disturbances, those that register in the range of a miniscule fraction of the width of an atomic nucleus. To detect such small differences, a pair of identical observatories—one in Livingston, La., and one in Hanford, Wash.—measures laser light that splits into two beams, shone down two opposing 4-km-long tunnels, bounced back, and measured with a light detector. All of those components must be painstakingly precise to be able to measure a phenomenon so small in a world that is so awash with interfering vibrations and movements. So the LIGO observatories house some of the most complex, expensive, and precise optics setups out there. LIGO’s critical laserbeam reflecting mirrors, called test masses, are huge hunks of fused silica supplied by Corning Incorporated. Each mirror weighs a hefty 40 kg and Credit: Caltech; YouTube is cast from an “ultrapure material with low hydroxide content to minimize infrared absorption,” according to the LIGO Caltech wesbsite. “Since LIGO’s laser is an IR laser, its optics must not absorb IR radiation. Doing so would result in heating and in significant changes to the shape of the mirrors, thus critically affecting LIGO’s ability to make the precise measurements it is designed to make. LIGO’s main mirrors absorb only one photon out of every 3.3 million, the others being reflected (or transmitted).” To absorb such little light, the mirrors are highly polished to nanometer smoothness and precision and are coated with dozens of layers of optical coatings to ensure that the 200-W laser beam travels precisely, smoothly, and with minimal loss through the interferometer. Installation of such an incredible optical system was no straightforward task, either. To minimize disturbances, LIGO’s optics float in space, suspended on glass fibers hanging from a four-part pendulum system. The complex system reduces background noise, canceling out as much measurement-disrupting movements of the world as possible. Because the observatories’ arms are so long, and must be so precise, even construction of the concrete tunnels that enclose the experiments themselves was no simple task. According to the LIGO website, “LIGO’s arms are so long that the curvature of the Earth is a measurable 1 m (vertical) over the 4-km length of each arm. The most precise concrete pouring and leveling imaginable was required to counteract this curvature and ensure that LIGO’s vacuum chambers were truly ‘flat’ and level. Without this work, LIGO’s lasers would hit the end of each arm 1 m above the mirrors they are supposed to bounce off of!” The paper describing the discovery, published in Physical Reviews Letters, is “Observation of gravitational waves from a binary black hole merger” (DOI: 10.1103/PhysRevLett.116.061102). n New 3-D printing process creates harder, stronger ceramics that can stand the heat Researchers at HRL Laboratories LLC in Malibu, Calif., have developed a way to additively manufacture ceramics that “overcomes the limits of traditional ceramic processing and enables hightemperature, high-strength ceramic components,” according to a recent HRL news release. Business news Saint-Gobain to export refractories from India, set up new R&D center (saintgobain. co.in)…Tethon 3D reaches Kickstarter goal for porcelain ceramic resin for 3-D printer in 48 hours (tethon3d. com)…Multinational companies perform majority of US business R&D (nsf.gov)… Alcoa wins fourth Boeing contract in string of recent deals (alcoa.com)…Rio Tinto agrees to sale of Mount Pleasant for $224M plus royalties (riotinto.com)… Owens Corning to acquire glass nonwovens and fabrics businesses of Ahlstrom (owenscorning.com)…GE Aviation cutting more than 7% of engineering workforce (geaviation.com)…Murata announces GRT series, automotive-grade monolithic ceramic capacitors (murata. com)…Saint-Gobain and Corning join to produce lightweight automotive glazing (saint-gobain.com)…ThyssenKrupp begins operation of world’s first automated sinter test facility (thyssen krupp-steel.com)…Digital modeling to enhance Morgan Advanced Materials’ brazed assemblies (morganadvanced materials.com)…Alcoa announces long-term contract with GE Aviation (alcoa.com)…US Silica announces price increases on silica and aplite products (ussilica.com)…Harper awarded major contract for nuclear material processing equipment (harperintl.com)…DOE announces $58M to advance fuel-efficient vehicle technologies (energy.gov)… DuPont deal and international sales push Blasch Precision to strongest year (blaschceramics. com)…NREL patents method for continuous monitoring of materials during manufacturing (nrel.gov)…PPG works on repairs at California glass facility (ppg.com)…New interactive website explores world of float glass manufacturing (worldofglassmap.com) n 6 www.ceramics.org | American Ceramic Society Bulletin, Vol. 95, No. 3


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