TWI

Based on a dynamical control-low stress no distortion (DC-LSND) methodology, an array jet impingement heat sink apparatus was designed to facilitate reductions of residual stress and distortion in friction stir welding (FSW), and test results were o…

A technique was developed to fill the exit hole during the retraction phase of a friction stir welding (FSW) sequence which, by using existing equipment functionality and designing a hollow FSW tool, syringe-type delivery system and pre-loaded alumi…

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…

A new "stop action" technique was used to investigate material flow during the friction stir welding of aluminium alloy 6061-T6 plate of thickness 6.4 mm (0.25 in). The technique involved stopping the welding process and examining the microstructure…

An investigation was made of approaches to tool design for the self reacting pin tool (SRPT) (bobbin tool) to mitigate the effects of friction stir welding owing to enlarged grains that occur in large structural extrusions, in order to yield accepta…

A review is presented of FSW (friction stir welding) tool design parameters and their relationship with heat generation, material flow and weld quality, including discussions of interaction mechanisms between tool and specimen, typical tool designs,…

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…

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…

Friction stir processing (FSP) was employed to fabricate oxide dispersion strengthened copper composites and the microstructure and mechanical properties of the materials were investigated in order to clarify the effect of process parameters on mate…

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…

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…

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…

The development of three-dimensional column-type friction stir welding (FSW) equipment for robotic FSW of joints with complex shapes is described. The process requires a large force and precision control for tool penetration. The specification of th…

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 …

An investigation was undertaken to examine the effect of adding aluminium to magnesium on the strength of dissimilar joints between steel and magnesium fabricated by friction stir welding. The materials studied were pure 3N magnesium, AZ31 (Mg, 2.9%…