TWI Digital Library

An economic analysis was undertaken to compare the costs of onshore and offshore pipeline construction scenarios for welds made using friction stir welding (FSW) and conventional mechanised MIG/MAG welding. Pipe diameters of 1067 and 305 mm were sel…

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 …

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…

The friction stir weldability of the dissimilar materials copper and aluminium alloy was studied, assessing the effects of different process parameters (rotation and traverse speeds, rotation direction (Cu or Al on advancing side), displacement and …

A report is presented into the development of a refill friction stir spot welding (FSSW) robot system, performance evaluation with respect to FSSW of aircraft aluminium alloys, and fabrication of full-scale aircraft production components. The FSSW r…

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…

A friction stir spot welding process variant was evaluated, which was intended to remove the hole left in the weld when the probe is removed, and consequently improve weld properties. In the two-step procedure, first a backing plate was used that ha…

Friction stir welding (FSW) experiments were undertaken on sheet specimens (thickness 4 mm) of AISI 304 stainless steel (17.5-19.5%Cr, 8-10.5%Ni) using different uncoated and coated tungsten and WC-based tools, and tool wear and failure mechanisms w…

Conventional friction stir welding (FSW), hybrid FSW and thermal stir welding were evaluated and compared for the joining of a nickel-based superalloy Haynes 230. Welds were made in Haynes 230 NiCrW alloy (20-24%Cr, 13-15%W, 6.4 mm thickness), an in…

Friction stir welding (FSW) was employed to fabricate hybrid joints between wrought AA 5454 aluminium alloys and AZ 91 die cast magnesium alloys, and the weldability, microstructure, mechanical properties, corrosion and fracture behaviour of the wel…

Guidance notes devised for Lloyd's Register of Shipping surveyors for use in the quality assurance of friction stir welded aluminium alloys are presented.The notes cover: welding equipment, materials welded, and welding requirements (weld qualificat…

Preliminary results from a 3-dimensional heat and material flow computer simulation program for friction stir welding are given and compared with experimental observations. The simulation is based upon solutions of Navier-Stokes equations and nonlin…

A high force, multi-axis friction stir welding (FSW) machine was employed to perform one-run welding experiments on thick plates (thickness 75 mm) of AA 6082-T6 alloys, and the hardness, microstructure and crystallographic texture of the joints were…

Friction stir welding (FSW) is a solid-state welding process, particularly suitable for aluminum alloys. The process allows the production of welds with a high seam strength and low distortion. Despite these benefits, irregularities can occur during…

Friction stir spot welded joints in aluminium alloy 6061-T4 were studied. Sheet of 1, 1.5, 2, and 3 mm thickness was friction stir welded to sheet of 3 mm thickness, using welds of 8-18 mm in length (equivalent in area to circular resistance spot we…

The effects of friction stir welding (FSW) on the microstructure, hardness, residual stress state and grain distribution of 2124 Al-SiC composite alloy were investigated. The composite was of AMC225xe aerospace AW2124 alloy reinforced with 25% SiC p…

Thermodynamic modelling and experimental measurements were employed to investigate the influence of intermetallic compound formation on the shear strength of dissimilar joints between an aluminium alloy and ultra-high strength steel fabricated by fr…

Ni3Al/Ni3V dual two-phase intermetallic alloys, incorporating Ta and Re additions, with enhanced high-temperature strength and hardness, were developed for friction stir welding tool applications and applied to fabricate butt welds in SUS 430 steel …

A methodology is presented to define conical tool geometry and process parameters for friction stir welding (FSW) of thin plates. A calculation algorithm integrating a basic thermal model, tool geometry and process kinematics is proposed, the proces…

The feasibility of friction stir welding TIMETAL 21S beta titanium in the annealed condition was investigated. The composition of the alloy is Ti, 14-16%Mo, 2.4-3.2%Nb, 2.5-3.5%Al, 0.15-0.25%Si, max.0.4%Fe, 0.11-0.17%O, max.0.05%C, max.0.05%N, max.0…