The Welding Institute (www.twi.co.uk/) has developed a new technique that uses its friction-stir welding technology to join aluminum alloy sheets that are 0.001-in. (0.3 mm) thick with lap welds or spot welds, or with sheets that are 0.02-in. thick (0.5 mm) with butt welds. The Welding Institute says the technique, called micro-friction stir welding ( FSW), produces welds at 3.94 ipm to 19.69 ipm (100 mm/min. to 500 mm/min.). The technique produces some of the smallest welds in the world, according to TWI. Potential applications include sealing packages within the electronics and photonics industry and welding aluminium foil for use in the aerospace industry. Applications also exist in other industries, including medical devices, consumer goods and food packaging.