TWI

The weldability of 2 mm thickness thixomoulded sheets of AZ91D magnesium alloy by friction stir welding (FSW) was studied as a function of tool rotation speed (880-1750 rpm) and specimen travel speed (50-500 mm/min). The composition of the sheet was…

An instrumented constrained Charpy test was used to measure the fracture toughness of friction stir welded joints produced using several designs of welding tool in sheet aluminium alloys 6082 (4.7 mm) and 7108 (3.2, 5.0 mm). This test constrained pl…

A series of models was used to study weld formation in 6000-series aluminium alloy in the friction stir welding process. Weld formation was considered as three separate thermomechanical processes: coupled friction heat generation; plastic flow slip …

Full field displacement measurement with digital image correlation was used to study the mechanical properties of friction stir welded joints in aluminium alloy plates. Welds were made in 5454-O and 5454-H sheet of 3.9 mm thickness, and 2195-T8 plat…

A stop-action technique was used to stop tool motion during friction stir welding of aluminium alloys in order to study the interactions between the parent material and welding tool pin in the keyhole. Welds were made in 25 mm thick Al-Cu-Li 2195 pl…

Following an overview of friction stir spot welding (FSSW) for potential automotive applications (including robotic FSSW in poke welding and C-frame configurations, and pedestal FSSW machines for manual, automatic or robotic use), a FSSW process dev…

Variations in microstructure in friction stir welds in AA 7449 (Al, 2.2%Mg, 8.2%Zn, 1.7%Cu, 0.12%Si, 0.15%Fe, 0.2%Mn, 0.05%Cr, 0.25 T plus Zr) in the initially overaged (T7) condition were studied. Isothermal heat treatments were conducted at 350 an…

This paper describes the joining criterion for lap joining of dissimilar metal materials of aluminum and stainless steel by friction stir. A criterion for evaluating the joined state or non-joined state is proposed, which is led by the concept based…

Experimental measurements and thermal modelling were used to determine the transient heat loss into friction stir welding tools and so calculate the welding efficiency. Energy inputs were determined from force and torque measurements made whilst per…

Experimental methods were developed to track material flow and mixing during the friction stir welding (FSW) process. Experiments were conducted with butt joints of 6.35 mm (0.25 in) thickness 7050-T7451 aluminium alloy plates. The FSW tool was H13 …

Alternative friction stir welding tool shoulder materials to improve welding speed and quality were evaluated. The materials, which were compared with tool steel using a tool designed for exchangeable shoulder inserts, were: nitrided tool steel, Inc…

As part of a study investigating friction stir welding (FSW) as a method for joining the lids on copper canisters for the long term storage of nuclear waste, finite element modelling was used to analyse heat flow and material flow and the developmen…

The effects of tool shoulder size and tilt angle on the formation of weld zones during the friction stir welding of aluminium alloys were studied. Aluminium alloy 5083 (Al, 4.2%Mg, 0.2%Si, 0.6%Mn, 0.15%Fe, 0.09%Cr, 0.09%Zn, 0.06%Cu, 0.02%Ti), an all…

The microstructure and mechanical properties (hardness profiles, tensile strength) of friction stir welded (FSW) joints of ZL114A cast aluminium alloy (Al, 6.5-7.5%Si, 0.45-0.6%Mg), a material of interest for applications in the aerospace industry, …

Friction stir welding (FSW) was applied to the magnesium alloy AZ91 (Mg, 8.21%Al, 0.64%Zn), optimum welding parameters were derived, structural and mechanical properties of the weld zone were determined, and the influence of microstructure on weld p…

The use of friction stir welding to produce aluminium alloy tailor welded blanks for automotive applications was investigated by measuring the hardness and microstructure of friction stir welds in aluminium alloy 5052 (Al, 2.46%Mg, 0.24%Fe, 0.15%Cr,…

Torsion testing was carried out using a range of temperatures and strains to simulate the formation of nugget zone grain structures in friction stir welds of a typical aluminium alloy (7010) in order to investigate the formation mechanisms. Electron…

The effects of pre and post weld heat treatments on the strength, fracture toughness and fatigue crack propagation of welds made by friction stir welding (FSW) in aluminium alloy 6013-T6 sheet material, which may replace the 2024-T3 skin alloy for f…

The microstructure and age hardening of friction stir welds in aluminium alloy plate 2014A-T651 (Al, 4.42%Cu, 0.79%Si, 0.62%Mg) and 7075-T651 (Al, 5.99%Zn, 2.72%Mg, 1.46%Cu) were investigated. Single sided butt welds were produced, temperatures bein…

An experimental and numerical analysis of the wear of a polycrystalline boron nitride (PCBN) friction stir welding (FSW) tool is overviewed as presentation slides. Topics highlighted include: FSW plunge trials of EH46 shipbuilding steel at a plunge …