AIST Stories No1

From AIST to the Innovative World30The Boeing 787 next-generation passenger jet made its maiden commercial flight between Japan’s Narita Airport and Hong Kong in October 2011 and the world’s attention was drawn toward this new aircraft. This was because of the anticipated improved fuel consumption through adoption of a lightweight airframe. Japanese company Toray’s carbon fiber composite material played a part in this light weighting. Carbon fiber composite materials are a strong field for innovative Japanese companies, and Japanese carbon fiber manufacturers command an approximately 70% share of global production. Moreover, this technology was discovered at AIST in the 1950s and as such, it is a technology with history.Carbon fiber developmentFrom fishing rods to aircraftCarbon fiber development processTechnology to society—the foundation of AIST’s innovation modelStrong, light, and thermally conductive “Top performer” of the materials worldCarbon fiber is obtained by firing an organic fiber and its carbon content is 90% or more. Its origins are said to date from the 19th century, when master inventor Edison carbonized Japanese bamboo by baking it and used it as the filament in incandescent lamps.The main features of this fiber are its light weight, strength, and hardness. It is one-quarter the weight of steel, yet possesses more than 10 times the strength and seven times the hardness. Furthermore, carbon fiber exhibits high fatigue resistance, corrosion resistance, vibration attenuation properties (vibration stops immediately), X-ray transmissivity, and thermal conductivity. On the other hand, its coefficient of thermal expansion is extremely low, meaning it exhibits excellent dimensional stability (size does not change). In all aspects, carbon fiber is a top performing material.Carbon fiber R&D gathered pace in the 1950s. Carbon fiber with high heat resistance was necessary for the U.S. space development program and a carbon fiber that employed rayon as a raw material was developed. Hearing of this, Dr. Akio Shindo of the Industrial Research Institute of Osaka, part of the Agency of Industrial Science and Technology under the Ministry of International Trade and Industry (one of the predecessor organizations to AIST) was eager to replicate this effort in Japan by all means; after substantial trial and error, he discovered that a higher performance carbon fiber could be synthesized by using polyacrylonitrile (PAN) fiber. An application was made for a patent for PAN-based carbon fiber in 1959.The Shindo Model: Cooperation with industry from the development phase Preparing the foundations for technology developmentInitial development of PAN-based carbon fiber assumed Another success at AIST!Source: Compiled based on Industrial Materials 47 (3) (1999, Nikkan Kogyo Shimbun, in Japanese) by Tetsuro TsunaiCarbon fiber application fields: Examples of application as CFRPSpaceand aero-spaceAircraft・‌‌‌Primary structural material: Main wings, tail wings, fuselages, floor beams・‌‌‌Secondary structural material: Ailerons, rudders, elevators, fairings・‌Interior materials: floor panels, lavatories, seatsRocketsSatellite fairings, intermediate stages, motor cases, nozzle throatsSatellitesAntennae, solar cell panels, tube truss structural materialsRadio telescopesAntennae, staysSportsequipmentand daily necessitiesFishing equipmentFishing rods, reelsGolfShafts, club heads, face platesRacketsTennis, badminton, squashAutomobilesFrames, wheels, steering wheels, cranksMaritimeYachts, cruisers, racing boats, mastsOther sportsBaseball bats, skis, ski poles, Kendo swords, Japanese archery bows, Western-style bows, radio-controlled cars, table tennis, billiardsCare giving productsWheelchairs, portable slopes for wheelchairs, prosthetic legs, walking sticksElectrical productsComputer housings, sound speakersOther articles of daily lifeUmbrellas, helmets, bags, furnitureIndustrialAutomobilesDrive shafts, exterior panelsMotorcyclesRacing cowlings, muffler coversRolling stock and containersRailroad vehicle bodies, linear motor car bodies, seatsMachinery componentsFiber components, leaf springs, robots armHigh-speed rotating equipmentCentrifuge rotors, uranium enrichment tubes, flywheelsIndustrial rollers, shafts, rayon spinning potsElectric componentsParabola antennaePressure vesselsCNG tanks, hydrogen tanks, firefighting air respirator cylindersChemical equipmentMixing impellers, pipes, tanksMedical devicesTop plates, cassettes, X-ray gridsBuilding and constructionConcrete reinforcing materials, cables, rodsOtherResin moldsSheet-form heating elements