{"id":4166,"date":"2026-05-21T01:42:15","date_gmt":"2026-05-21T01:42:15","guid":{"rendered":"https:\/\/zxweldingrobot.com\/?p=4166"},"modified":"2026-05-21T01:42:15","modified_gmt":"2026-05-21T01:42:15","slug":"friction-stir-welding","status":"publish","type":"post","link":"https:\/\/zxweldingrobot.com\/es\/blog\/friction-stir-welding\/","title":{"rendered":"Soldadura por fricci\u00f3n y agitaci\u00f3n (FSW): aplicaciones aeroespaciales y de bandejas de bater\u00edas para veh\u00edculos el\u00e9ctricos"},"content":{"rendered":"

Friction stir welding (FSW) solves the problem arc welding cannot: joining high-strength aluminum alloys that crack when they cool from a liquid melt. Since Wayne Thomas invented the process at TWI in 1991, FSW has expanded from aerospace R&D into automotive production lines, EV battery manufacturing, and large-scale shipbuilding. A September 2025 breakthrough from Pacific Northwest National Laboratory has now cleared the last barrier to flexible assembly-line robotic FSW deployment.<\/p>\n

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Quick Specs: Friction Stir Welding (FSW)<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n
Process type<\/td>\nSolid-state joining \u2014 base material never melts<\/td>\n<\/tr>\n
Operating temperature<\/td>\n80\u201390% of base material melting point<\/td>\n<\/tr>\n
Invented<\/td>\n1991, TWI Ltd, Cambridge UK (Wayne Thomas)<\/td>\n<\/tr>\n
Primary material<\/td>\nAluminium alloys \u2014 all grades 1xxx through 7xxx<\/td>\n<\/tr>\n
Also welds<\/td>\nSteel, titanium, copper, nickel, dissimilar metals<\/td>\n<\/tr>\n
Thickness range (Al)<\/td>\n0.3 mm \u2013 75 mm, single pass<\/td>\n<\/tr>\n
Key standards<\/td>\nAWS D17.3\/D17.3M:2021 (aerospace) \u00b7 ISO 25239 (general)<\/td>\n<\/tr>\n
4 control parameters<\/td>\nDownforce \u00b7 rotational speed \u00b7 travel speed \u00b7 tilt angle<\/td>\n<\/tr>\n
Consumables (Al)<\/td>\nNone \u2014 no filler wire, shielding gas, or flux<\/td>\n<\/tr>\n
Exit hole<\/td>\nYes \u2014 design accommodation required at weld termination<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

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What Is Friction Stir Welding?<\/h2>\n

\"What<\/p>\n

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Friction stir welding is a solid state welding<\/strong> process \u2014 the base material never reaches its melting point. A non-consumable tool consisting of a shoulder and a probe pin<\/strong> rotates at high speed and plunges into the joint between two workpieces. Frictional heat raises material temperature to 80\u201390% of its melting point, causing the metal to plasticize without liquefying. The rotating tool<\/strong> then traverses along the joint line, mechanically stirring the softened material and forging a solid state joining<\/strong> bond behind it.<\/p>\n

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Three zones define the weld cross-section. The weld nugget<\/strong> directly beneath the tool shoulder undergoes dynamic recrystallization<\/strong>, producing fine equiaxed grains with superior mechanical properties compared to cast fusion weld metal. The thermomechanically affected zone<\/strong> (TMAZ) surrounds the nugget \u2014 mechanically deformed but not recrystallized. The outer heat affected zone<\/strong> (HAZ) is thermally altered without mechanical deformation, similar to arc welding HAZ but considerably narrower.<\/p>\n

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Wayne Thomas at TWI Ltd in Cambridge, UK invented FSW in 1991. TWI describes it as achieving “one of the shortest times from invention to widespread industrial use” \u2014 commercial aerospace production adopted FSW within four years of its patent filing. The absence of the liquid phase is the process’s defining metallurgical advantage: since material never melts, solidification defects (porosity, hot cracking, solidification segregation, slag inclusions) cannot physically form. This is why FSW is the enabling joining technology for the 2xxx series<\/strong> and 7xxx series<\/strong> of aluminum \u2014 the high-strength alloys classified as “non-weldable by conventional arc processes” due to their susceptibility to solidification cracking.<\/p>\n

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See also: Industrial welding process overview<\/a><\/p>\n

How the FSW Process Works: The 4 Key Parameters<\/h2>\n

\"How<\/p>\n

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Each FSW pass runs in three sequential phases: plunge<\/strong> (the rotating tool descends until the shoulder contacts the workpiece surface), dwell<\/strong> (brief rotation builds thermal equilibrium at the joint), and traverse<\/strong> (the tool moves along the joint at controlled travel speed while maintaining downforce). The weld consolidates directly behind the advancing shoulder.<\/p>\n

Four variables control every FSW outcome:<\/p>\n