TWI Digital Library

The feasibility of short-cycle friction stir spot welding for joining thin sheet aluminium alloys and steels, both galvanised and ungalvanised, was evaluated. Welds were made between 6111-T4 AlMgSi alloy (Al, 0.75%Cu, 0.25%Fe, 0.75%Mg, 0.2%Mn, 0.69%…

The results of quality assessments, based on visual examination, mechanical testing, analysis of weld structures and hardness testing, of both similar and dissimilar friction stir welded (FSW) joints of aluminium casting alloys EN AC-42100, EN AC-43…

A fully coupled thermomechanical formulation was proposed for the numerical modelling of friction stir welding (FSW) to facilitate the efficient simulation of different types of material flows and accurate computation of the resulting thermomechanic…

With regard to the capability of ultrasonic vibration enhanced friction stir welding (UVeFSW) to improve weld formation quality as well as the microstructure and mechanical properties of the welded joints, experiments were undertaken to clarify the …

The friction stir welding (FSW) process was determined for stiffener to skin lap joints of different aluminium alloys (similar 2024 T3, similar 2139 T3 and T8, dissimilar PA 765 T79 extrusion on 2139 T8 skin) and FSW procedures with retractable pin …

Square butt welds of AA 7075-T6 sheet (thickness 1.3 or 3.2 mm) to AA 7075-T6 extrusions were fabricated by friction stir welding (FSW) procedures incorporating the controlled introduction of defects, and the impact of the defects on joint mechanica…

To assess the feasibility of friction stir welding of Ti-6Al-4V alloy (thickness 5 mm), appropriate pin tool material and processing parameters were determined, thermal and environmental management systems were tested, and both A- and B-basis design…

Two 3D numerical simulation models were employed to investigate the relationship between forces and torques during high-speed friction stir welding (FSW) with respect to mechanistic defect development owing to process parameter variations, and the t…

A friction stir welding (FSW) methodology, incorporating Taguchi quality engineering to optimise process parameters, was developed to fabricate a cold plate consisting of copper pipe embedded in the machined groove of a 6061 aluminium alloy base pla…

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…

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…

Modelling tools were developed to describe the relationships between process parameters, microstructural evolution and mechanical properties of the weld in friction stir welding (FSW). Experiments were conducted using aluminium alloy 6056. Initial t…

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…

Computational fluid dynamics (CFD) methods were used to model the metal flow in the friction stir welding (FSW) process in order to optimise the pin profile to minimise the traversing force; welding experiments were carried out to validate the findi…

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…

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…

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…

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…