TWI

An investigation is presented into the use of temperature control in two friction stir welding (FSW) research projects: to understand the effect of backing plate conductivity on process parameters and to study the influence of active FSW tool coolin…

In relation to the development of corrosion barrier capsules for spent nuclear fuel disposal, friction stir welding experiments were conducted on oxygen-free copper plate specimens (thickness 20 mm) using different joint preparation, shielding gas a…

Dissimilar lap joints between aluminium alloys and various steel grades were fabricated by friction stir welding (FSW), FSW tool wear was measured and a phenomenological law was developed with respect to pin length reduction over weld length to repr…

An experimental investigation was made of the effect of welding tool shape on welding defects and material flow during friction stir welding (FSW) of dissimilar materials. Friction stir welding tools used had tool shoulders of tool steel and the pro…

Friction stir welding experiments were undertaken on 2195-T8 (Al, 3.99%Cu, 1.09%Li) alloy sheets (thickness 5 mm) and the weldability, microstructure and mechanical properties of the fabricated butt joints were investigated. Welding was performed us…

A comparative study was undertaken of three different machine types, a modified high payload robot, a CNC milling machine and an ESAB "SuperStir" FSW machine, in terms of their capability for FSW of various aluminium alloys using identical process p…

Weld zone simulation and ballistic testing were employed to determine the effect of friction stir welding on the ballistic performance in the HAZ, thermomechanically affected zone and nugget, under direct impact, of AA 7010-T7651 high-strength alumi…

Friction stir welding (FSW) experiments were conducted on magnesium alloys, wrought AZ31 (Mg, 3%Al, 1%Zn) and cast AZ91 (Mg, 9%Al, 0.6%Zn), to investigate the effect of process conditions on microstructure and hardness. Welding was performed at rota…

A controller was developed and tested for the friction stir welding of copper canisters, used in the nuclear industry. The cascaded loop controller determines the power input requirement and tool temperature to achieve a stable, robust and repeatabl…

Butt joints were fabricated in sheet specimens of 2017A-T451 alloys (Al, 4.14%Cu) and cast plates of Al, 8.6%Si, 0.31%Mg by friction stir welding (FSW) and their microstructure and mechanical properties were investigated. Welding experiments were co…

A review is presented of the progressive emergence of conceptual tools associated with friction stir welding (FSW) at the Marshall Space Flight Center, USA, from the discovery of the shear surface, wiping metal transfer and the invention of a kinema…

With regard to the fabrication of closure welds for used fuel containers, a series of experiments was undertaken to demonstrate the feasibility of creating defect-free partial penetration welds by friction stir welding (FSW) in A516 Grade 70 steel (…

Friction stir welding was employed to fabricate welded joints in AA 7475-T7351 aluminium alloy plates (thickness 6.35 mm) and the effect of kissing bond defects on fatigue life and other mechanical properties was investigated. Welded test specimens …

A thermal-pseudo-mechanical model, based on the use of material temperature-dependent yield stress as the driver for heat input, was proposed for heat generation in friction stir welding, and simulation results were compared with experimental temper…

A two-step modelling procedure, consisting of a thermo-fluid model and a thermo-mechanical model, was employed to predict temperature, flow and residual stress fields around the workpiece block, steel backing plate and tool in friction stir welding …

The application of suitable friction stir welding (FSW) tools and procedures to common structural geometries in industry, with emphasis of FSW of hard metals including steel, titanium and nickel based alloys in butt, T-joint, corner joint and circum…

An experimental investigation is presented into the fatigue properties of welded joints made by friction stir welding (FSW) of 2024-T4 (Al, 4.4%Cu, 0.6%Mn, 1.5%Mg) and 2014-T6 (Al, 4.5%Cu, 0.8%Mn, 0.5%Mg) aircraft alloys and their dependence on proc…

Extruded AZ31 (Mg, 3%Al, 1%Zn) alloy plates (thickness 6 mm) were joined by one-run or two-run friction stir welding (FSW) and the microstructure, mechanical properties and residual stress characteristics of the welded joints were investigated. FSW …

Friction stir welding experiments were undertaken on Ti-6%Al-4%V sheets (thickness 2 mm) in order to investigate the influence of process conditions on stir zone microstructure and local texture. Welding was performed at rotational speeds of 225-300…

A hybrid welding system called ultrasound supported friction stir welding was developed to mitigate the strength reducing effects of brittle intermetallic phase layers and was applied to the fabrication of dissimilar joints between wrought aluminium…