TWI

A mobile friction stir welding (FSW) machine, comprising a self-contained truck with four wheels, was proposed for use when welding large structural members made from aluminium alloys and the concept was verified by welding trials using a prototype …

A device was designed and manufactured to facilitate accurate monitoring of forces, torque and tool temperature during friction stir welding (FSW) and for use as a weld quality indicator in relation to issues such as tool wear, lack of tool penetrat…

In the last fifteen years, friction stir welding has developed from a laboratory curiosity to an important fabrication technique for lightweight, lower softening temperature alloys. Industrial implementation of joining magnesium has been limited alm…

A simultaneous double sided corner Ad-Stir fillet stationary shoulder friction stir welding (SSFSW) process was developed for LNG (liquefied natural gas) storage tank construction. The microstructure and mechanical properties of welded joints were i…

The relationship between microstructure and hardness was investigated in friction stir welded aluminium alloy 6063-T5. The alloy thickness was 6 mm. Hardness profiles were measured across the stir zone. The microstructure of the as-welded and postwe…

A review of an experimental study of friction stir welded (FSW) 5456-H1 16 aluminium plate of 19 mm thickness, is presented and the formation of a pre-rotation defect and its effect on the mechanical properties of welds is discussed. Welds were made…

Analytical modelling and experimental measurements were undertaken to investigate a dual-loop temperature control algorithm for friction stir processing, incorporating an inner loop to maintain constant power and an outer loop to set the power based…

Friction stir welding (FSW) was carried out on A-6N01-T5 aluminium alloy of thickness 15 mm in various restraint conditions, and the amount of deformation before and after welding was investigated. Vertical distortion and lateral shrinkage of the we…

The influence of tool and plate positions on the friction stir welding of F82H ferritic/martensitic steel (0.1%C, 8%Cr, 2%W, 0.2%V, 0.04%Ta) and austenitic stainless steels 304 and 316 was investigated. Stainless steel compositions were: 304 (0.08%C…

To overcome the limitations associated with conventional friction stir welding, particularly for complex shaped large structures, the bobbin tool technique was developed and demonstrated on various aluminium alloys (4-15 mm thickness range), the tec…

A spot FSW robot system was developed and used to weld lap joints in aluminium alloys (used mainly in car body assembly) and the static strength of the welded joints was compared with resistance spot welded joints. A prototype spot FSW gun was combi…

The development and use of friction stir powder processing (FSPP) to overcome defect formation and to control mechanical properties is discussed and FSPP of AA 1050 aluminium (Al, 0.06%Si, 0.34%Fe, 0.02%Cu) is reported. In FSPP, powder with a contro…

A numerical model of the friction stir welding (FSW) process was developed by employing finite element analysis of a non-Newtonian fluid to evaluate plastic deformation and heat generation of the weld material, and was applied to the design of tool …

Dissimilar lap joints between ASTM A36 low carbon steel and Inconel 625 (Ni, 21.4%Cr, 9.65%Mo, 3.2%Nb, 2.6%Fe) were fabricated by friction stir welding (FSW) and the effects of process parameters on microstructure and hardness were investigated. FSW…

A simplified friction stir welding (FSW) tool equipped with an adjustable probe was developed, FSW trial results with prototype tools were obtained and were analysed in terms of weldability. The simplified tools were realised by devising shoulders f…

With regard to the use of friction pull plug welding to close out the termination hole associated with pin tool retraction during friction stir welding of circumferential welds in pressurised cryogenic propellant tanks, an investigation is presented…

An investigation was undertaken to examine the use of an industrial serial robot incorporating dual loop force/position control to reduce the investment cost and increase process flexibility in friction stir welding (FSW) by compensating the lateral…

Two initiatives are presented to develop friction stir welding (FSW) and friction stir spot welding (FSSW) design data for the aerospace industry: a path independence initiative for FSW butt joints and qualification of FSSW welds for lap joints as i…

With regard to the application of AA 2219 aluminium alloys to space launch vehicle propellant storage tanks, an investigation is presented into the influence of process parameters (tool rotational speed, shoulder downward force and weld transverse s…

The effects of multiple overlapping friction stir weld runs (with 100% overlap) on the welding parameters and weld properties during the repair of high-strength AlCuMgZn alloy were investigated. Square butt welds were made in 7050-T7451 alloy (Al, 6…