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Friction stir welding uses frictional heating combined with forgingpressure to produce high-strength bonds virtually free of defects.The welding process transforms metals from a solid state into a"plastic-like" state, and uses a rotating pin tool tosoften, stir and forge a bond between two metal plates to form auniform welded joint -- a vital requirement of next-generationspace hardware. "NASA is leveraging key technologies like friction stirwelding from the Space Shuttle Program to design and manufacturethe Space Launch System," said Todd May, SLS program managerat the Marshall Space Flight Center in Huntsville, Ala."NASA's advancements in friction stir welding techniques usedto manufacture the external tanks give SLS a head start indevelopment while reducing program cost, increasing reliability andcreating hardware with superior mechanical properties. Thistechnology directly supports SLS' program tenets of safety,reliability and sustainability." In the mid 1990s, following use of a new lightweight aluminumlithium alloy created to reduce the weight of the external tanks,Marshall engineers found the new alloy difficult, complex andcostly to weld. Engineers researched and adapted the innovativefriction stir welding process for use on the 153.8-feet-tall orangespace shuttle external tanks used to hold propellant for the spaceshuttle main engines. The process reduced manufacturing costs,increased reliability and significantly lowered the number ofdefects to yield a nearly perfect weld. The Space Shuttle Program implemented the new weld technique in itsmanufacturing process of the external tank in 2001. The firstfriction stir welded tank flew in 2009. Since then, NASA hasdeveloped multiple tools and advanced processes to enhance itswelding capabilities on aerospace hardware. "State-of-the-art friction stir welding will continue to be acritical technology as we continue to learn how to build moreefficient space vehicles with less expensive materials," saidJon Street, welding and manufacturing lead in the Material &Processes Laboratory at the Marshall Center. "Friction stirwelding yields higher strength metals with higher reliability andpredictability. It also increases efficiency by reducing the numberof weld passes that traditional fusion arc welding requires. Inaddition, it offers safer, more environmentally friendly operationsthan traditional welding by not creating hazards such as weldingfumes, radiation or high voltage. SLS will benefit from all ofthese advancements." Today, the Boeing Company of Huntsville, Ala., is developing theSLS core and upper stage using the friction stir welding process.The core stage will tower over 200 feet tall with a diameter of27.5 feet and store cryogenic liquid hydrogen and liquid oxygen tofeed RS-25 engines. The upper stage, powered by J-2X engines, willbe used on the evolved SLS and share common attributes with thecore stage such as its outer diameter, material composition,subsystem components and tooling. Both stages will be built atNASA's Michoud Assembly Facility in New Orleans withstate-of-the-art manufacturing equipment and tooling -- includingone of the largest robotic friction stir welding systems in theworld. "NASA's strategy to affordably achieve a 2017 first flight forits new launch vehicle depends a great deal on the ability toleverage existing technologies and expertise, while takingadvantage of the new science and innovations necessary to achieveextended flights of discovery," said Jim Chilton, BoeingExploration Launch Systems vice president. "Friction stirwelding technology meets all of those challenges.". I am an expert from wellmedlab.com, while we provides the quality product, such as China Gauze Dressings , Medical Respirators Manufacturer, Urinary Bag,and more.
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