TWI Digital Library

Friction stir welding (FSW) was investigated in aluminium alloys used in aircraft structures. Extruded shapes in alloys 2024 (Al, 4.96%Cu), 7475 (Al, 5.96%Zn, 2.57%Mg, 1.62%Cu) and 7050 (Al, 6.29%Zn, 2.36%Mg, 2.00%Cu) were welded; welds were evaluat…

The influence of friction stir welding on the microstructure and mechanical properties of aluminium alloy 6061 was investigated. Aluminium alloy 6061-T651 plate of 6.4 mm (0.25 in) thickness was friction stir welded and the joints characterised by o…

Friction stir welding (FSW) has been widely used in the automotive, aerospace, and high-tech industries due to its superior mechanical properties after welding. However, when it becomes matter to perform a high-quality joint using FSW, it is necessa…

The deformation behaviour and microstructural evolution of friction stir processed Zn, 22%Al rolled sheet (thickness 3 mm) were compared with those of the corresponding superplastic alloy. Friction stir processing was performed at a rotational speed…

Following a description of the swept FSW spot welding process, experimental work on welding conditions is presented. A design of experiments (DOE) approach was employed to examine the effect of process parameters on unguided lap shear tensile streng…

6061-T6 aluminium alloy (Al, 0.96%Mg, 0.59%Si) sheets (thickness 1 mm) were joined by friction stir spot welding (FSSW) under low rotational speed conditions and the microstructure and mechanical properties of the welded joints were investigated. FS…

Lap joints were fabricated in AA 7075-T6 aluminium alloy sheets (thickness 2 mm) using an ESAB "Rosio" friction stir welding (FSW) robot and the effect tool of side-tilt angle on welded joint tensile strength was investigated. A "CounterStir" FSW to…

An investigation is presented into the development of the stationary shoulder self-reacting pin tool (SSSRPT) as a friction stir welding variant and the application of the tool to fabrication of butt joints in sheets (thickness 4 mm) of A6N01 alloys…

An investigation is presented into tool material development of large polycrystalline cubic BN blanks to facilitate friction stir welding of thick section steel specimens (thickness 9.5 or 20 mm). Tool materials were produced from 90% polycrystallin…

A refill friction stir spot welding (RFSSW) process with a short welding cycle time was employed to fabricate welded joints in thin gauge AA 6111-T4 aluminium alloy sheets (thickness 0.9 mm) and the mechanical properties of the joints were investiga…

An apparatus was developed to analyse the contact condition between the rotating tool and the workpiece during friction stir welding, and empirical tests were performed to determine the friction conditions (static, dynamic and the transition from on…

An investigation is presented into the effect of a paint bake cycle on the performance of friction stir spot welded (FSSW) joints fabricated in heat-treatable 6111-T4 aluminium alloy automotive sheets (thickness 0.93 mm) using a pinless tool and sho…

An ultrasound assisted friction stir welding (UA-FSW) technique was employed to fabricate butt joints in similar Al/Al and dissimilar Al/Mg sheets, and the influence of ultrasonic oscillations on weld zone microstructure and mechanical properties wa…

Dissimilar welded joints between AW 6061-T6 aluminium alloy (Al, 0.93%Mg, 0.59%Si, 0.5%Fe) and AZ31B-H24 magnesium alloy (Mg, 2.55%Al, 0.79%Zn) were fabricated by friction stir welding and the influence of process parameters on their microstructure …

The results of a programme to establish self reacting friction stir welding for thin gauge (less than 3 mm) aluminium alloy applications are reported divided into the five major phases: tool development; joint evaluation; strength optimisation; prot…

Work from two projects is described: "Qualistir" for the on-line quality control of friction stir welding in aluminium (by ultrasonic phased array examination of butt welded Al 7075); and a TWI feasibility study on inspection of Al 5083 butt and lap…

The influences of the thermal and mechanical stresses experienced during friction stir welding on the structure of coarse-grained aluminium alloy 2519-T87 were investigated. Plate of 25 mm thickness was welded at a speed of 1.5 mm/s, using a tool sp…

A procedure has been developed for repairing welds made by friction stir welding (FSW) in cases where the tool breaks during welding. It involves the following stages: excavating the broken FSW tool, milling out a slot across the hole, machining an …

The quality of friction stir welds of butt joints (including the use of inserts to simulate compensation for poor fit up) between aluminium alloys 5083-H12 (Al, 4.6%Mg, 0.6%Mn, 0.3%Si) and 6082-T6 (Al, 0.7%Mg, 0.9%Si, 0.5%Mn), was evaluated. The wel…

Local stress-strain curves were determined from an array of spherical indents on the cross-section of the joint of a friction stir welded (FSW) high strength aluminium alloy AA 2198 sheet, in order to characterise the mechanical properties of differ…