Friction Stir

admin

http://qz.com/18889/heres-the-obscur...-the-new-imac/Today’s big reveal of the iMac’s razor-thin edgeAppleApple just announced that the new iMac was made possible by an obscure metal joining process called Friction Stir Welding. Invented in 1991, friction stir welding “works by mechanically intermixing the two pieces of metal at the place of the join, transforming them into a softened state that allows the metal to be fused using mechanical pressure, much like joining clay [or] dough.” It’s different from normal welding in that the metal doesn’t melt, so it’s good “for applications where the original metal characteristics must remain unchanged as much as possible.”The Welding Institute near Cambridge, UK, invented this welding method and holds the patent on the process. It’s not known what sort of licensing fee Apple is paying in order to use the process.
Reply:Thanks for posting. I will look into this it will help teach a concept or two in my science class.Dave ReberWadsworth Ohio
Reply:Hi, is this cold fusion.....LOL.I know if you have two surfaces that are not lubricated, IE that run out of lubricant such as plain bearings, the two surface will "pick up, fret" whatever the term, and almost weld together.I could imagine if two surfaces were to be in contact with an ultra high frequency vibration present, then with some pressure they would bond together, no heat needed, but probably some heat would be generated at the contact point, so making a plastic deformation as the two interfaces join.You can see how much friction is generated when you rotate a hard wood stick in a hole in another piece of wood and the friction is enought to make the wood catch fire.You can also see the friction effect by putting a 9mm diam rod in a drill press and just rotating it at top speed against a piece of steel plate....after a very short while the end will get red hot and mushroom out.I read somewhere that you can drill a hole with a carbide drill rotating at high speed,  without any cutting edges, but by friction alone....the metal to be pierced is softened by the friction and the carbide point just pushes through.BTW, if you want to have sheet metal with ordinary screws that are tapped into the metal ,but not use self tappers, then make the tip of your tapping size drill blunt and use some force to create friction.......the drill bit won't cut the metal but heats it and softens it, then the drill just pushes through the metal and forms a hole at least 4 times the metal thickness allowing threads to be tapped in the hole.Ian.Last edited by puddytat; 10-23-2012 at 07:49 PM.
Reply:Friction Stir Welding is used extensively in the space program. Shuttle external tanks are (were) welded with this process, as well as Delta and Space X rocket segments.I had experience with another friction welding process. Bobcat skid steer loaders use friction welding on the hydraulic cylinders, where the rod joins the eye. I saw a video where they spin the cylinder rod at high speed and simultaneously press it against the stationary eye. You can see the rod end turn almost yellow with heat. At just the right moment, the rotation of the rod is suddenly stopped and it's pushed into the eye with additional pressure. The entire cross section of the rod is welded to the eye.Miller Thunderbolt AC/DC (Sold)Miller Dialarc 250HFMiller MM251Miller MM200 (Sold)Miller MM130Miller Spot WelderVictor O/A rigMiller Spoolmatic 1 (Sold)
Reply:I have done the same thing with extremely high R.P.M. and zero oil pressure....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Well you got ipad ipod iphone now introducing iwelder . Miller Dailarc HF 250 Hobart 140
Reply:Titanium poppet valves (normal valves used in engines) are assembled using spin welding.  My boss got a tour of one of the CV products, I forget the brand, titanium valve spin welding machines, said it was awesome to watch.  The valves are hollow stem and hollow head, assembled in 3 parts and spin welded to join them.  The machine looks like a lathe with a hydraulic head stock, white sparks go flying, a valve is born and can be handled within seconds of it being taken out of the machine.Lots of videos of the spin welding processes on youtube, mostly axle housings for large trucks.The welding procedure used on the new Mac laptop sounds similar to ultrasonic plastic welding.  My last school had a plastic welding machine but it was never hooked up...~Alex
Reply:MTS built friction stir welders and just sold the line to PAR Systems... a few intern friends of mine have worked on the porject at PAR, very undramatic to watch to be honest.
Reply:several auto makers have been friction stir welding now for quite a while.    Im pretty sure that all the new GM driveshafts are friction stir welded.    The biggest hassle with the process is having to have a run off area to plunge and withdraw the tool thats not in the finished weld zone.Vantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:Originally Posted by zapsterI have done the same thing with extremely high R.P.M. and zero oil pressure....zap!
Reply:pretty neat i was an operator at a place that friction stir welded aluminum deep sea drilling risors  along with navy boat haulsMiller Xmt 350Lincoln Ln-25Ahp 200xSmith Gas Mixer AR/HTig is my Kung FuThrowing down dimes and weaving aboutInstagram http://instagram.com/[email protected]
Reply:Originally Posted by zapsterI have done the same thing with extremely high R.P.M. and zero oil pressure....zap!
Reply:I used to work for an electric motor manufacturer.  Pool and spa motors have a stainless steel pump shaft.  but for lower cost and better mechanical properties, only the segment of the motor shaft that extended outside the motor housing was stainless steel.  The carbon steel shaft worked better for the interference press fit of the rotor as well.This stainless steel section was welded by spinning and pressing it into the mild steel portion of the shaft.  The two halves would mushroom and glow red-hot.  The excess was machined off and the shaft was turned and ground to the necessary finished dimensions.  Usually made for a perfect weld, every time.Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:I think the micro level that they are doing it at is what is amazing."The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life." -Theodore Roosevelt
Reply:Originally Posted by A_DAB_will_doI used to work for an electric motor manufacturer.  Pool and spa motors have a stainless steel pump shaft.  but for lower cost and better mechanical properties, only the segment of the motor shaft that extended outside the motor housing was stainless steel.  The carbon steel shaft worked better for the interference press fit of the rotor as well.This stainless steel section was welded by spinning and pressing it into the mild steel portion of the shaft.  The two halves would mushroom and glow red-hot.  The excess was machined off and the shaft was turned and ground to the necessary finished dimensions.  Usually made for a perfect weld, every time.
Reply:Session 12 Plenary-2 D Bolser.pdfSession 12 Plenary-1 S H C Park et al ABSTRACT.pdfActivity on FSW in the U.S.
Reply:ISO 25239 and AWS D17.3 are standards for FSW aluminium.
Reply:Originally Posted by Drf255Me too
Reply:It seems that many are getting friction stir welding confused with inertia friction welding (uses a large weight that causes the part to keep spinning after it collides with the other part) and continuous drive friction welding (uses a hydraulic motor to spin the part and drive it through the welding process until it stops to finish).  These are both only possible on round shapes.  Friction Stir welding uses a spinning steel tool to join some steel, Aluminum, copper, etc together in a butt or lap joint.  It is a solid state welding process that does not melt the base material in the welding process.  It can weld several inches of aluminum in one pass.  As a side note the company with the most installed FSW systems is ESAB.  They even have a system on the end of a robot arm that is capable of welding around curves.Hope this information helps clear up misconceptions and aids in further research in alternative welding methods.I play with Robots and do some welding.
Reply:TWI publishes ground breaking developments for friction stir welding of steel09 October 2012  Friction stir welding, as used in aluminium rail cars for example, can now be used for steel Stephen Cater, a researcher at TWI Technology Centre at the Advanced Manufacturing Park, Sheffield, has presented ground-breaking results on friction stir welding of steel at the 9th International Conference on Trends in Welding Research, Chicago, USA. Friction stir welding was initially invented by TWI for welding aluminium and has quickly become the process of choice for world-leading manufacturers such as Boeing, SpaceX, Hitachi, Mazda and Volvo for the fabrication of strong, stiff, lightweight aluminium structures. Following its widespread acceptance by the aerospace, shipbuilding, train making and automotive industries for manufacturing aluminium structures, TWI is developing friction stir welding (FSW) for application to steel. Recent work at TWI Technology Centre in Yorkshire has shown that welds in steel made by friction stir welding have considerably better mechanical properties than those made by conventional arc welding, for example significantly improved toughness and fatigue lives. The lack of melting and thus low heat input – characteristic of the friction stir welding process – reduces distortion in the welded structures.Results just published show that for 6mm thick, high strength shipbuilding steel, FSW reduces distortion along the length of a 2m welded plate from 115mm to 15mm while tripling weld toughness and increasing fatigue life compared to submerged arc welding. As up to 40% of the costs of building a ship are associated with correcting distortion of welded plates, this new technique has potential to introduce considerable cost savings during manufacture.Process advantages:Unlike conventional welding techniques, FSW does not melt the metal being welded and results in strong, defect-free welds without fear of health and safety concerns from any of molten metal, fumes or ultra-violet light. The process also offers cost savings when compared with conventional arc welding of aluminium.Industry benefits:Stronger welds than currently possible using existing techniquesVery low distortion, making significant savings on rework and post-weld straighteningImproved fatigue and toughness, leading to better in-service performanceImproved Health and Safety conditions in the welding environment.
Reply:at uno we recently had a fsw donated. it came from the michoud plant in new orleans east.  they used to make external rocket tanks for space shuttle, weve been getting all kinds of equipment that nobody knows what to do with.  this fsw is probably going to sit there for a long time, nobody knows how to run it or what to do with it if they did. Attached Images