TWI

The mechanical properties and microstructures of dissimilar butt welds made between aluminium die casting alloy ADC1 (Al, 11.9%Si, 0.37%Fe, 0.44%Mg) and the extruded alloy A-6061-T6 (Al, 0.84%Mg, 0.67%Si) were studied. The materials were 4 mm thick …

The production of aluminium alloy forged suspension parts for light-weight vehicles using circumferential friction stir welding (FSW) is considered. The suspension arm is composed of three extruded shapes (bush bracket, yoke and pipe) joined by FSW.…

The microstructure and mechanical properties of double-sided welds made by friction stir welding (FSW) in aluminium alloy AA-5083 were investigated as part of research into the use of the alloy in vessels for storing liquid hydrogen at cryogenic tem…

The microstructure of a friction stir weld (of unknown welding parameters) in titanium alloy (Ti, 6%Al, 4%V) is described. The microstructure was studied using optical microscopy, SEM and TEM. The features of the parent material, HAZ and the thermom…

A process model for friction stir welding (FSW) of Al-Zn-Mg alloys, used to predict HAZ microstructure and hardness, is presented. Numerical solutions (using a finite difference approach) are developed for heat generation and heat flow. Microstructu…

A friction stir welding (FSW) procedure, incorporating the use of different tool pins in combination with concave or scroll type shoulders, was employed to join various aluminium alloys; material flow was investigated with the aid of computer micro-…

A feasibility study is presented for the joining of mild steel plates (0.2%C, 0.11%Si, 0.63%Mn) of 12 mm in thickness by friction stir welding (FSW). Process optimisation using a combination of operating parameters and tool geometries is discussed, …

Three recently published finite element studies, modelling friction stir welding (FSW) of different aluminium alloys, were reproduced using ABAQUS software and the results were comparatively assessed. The models considered were as follows: heat tran…

The tensile and bend properties of friction stir welded butt joints in aluminium alloys 2024-T3, 6013-T6 and 7475-T76 were determined, including welds in 2024 and 7475 subjected to PWHT. The ultimate tensile strength, proof stress at 0.2% strain, an…

An indirect temperature measurement system was developed based on the acquisition of torque and process forces during friction stir welding (FSW) and a mathematical model incorporating a grey box approach was formulated to determine the correlation …

In relation to the industrialisation of the friction stir welding process to facilitate qualification of welding machines for different applications, a methodology is presented based on the interactions between tool, workpiece and material. Issues d…

Dissimilar joints between 6061-T4 aluminium alloy and S45C steel sheets (thickness 1.6 mm and 1 mm, respectively) were fabricated by the friction stir clinching technique using two types of tools and their mechanical properties and failure modes wer…

Friction stir welding (FSW) was applied to the magnesium alloy AZ91 (Mg, 8.21%Al, 0.64%Zn), optimum welding parameters were derived, structural and mechanical properties of the weld zone were determined, and the influence of microstructure on weld p…

As part of a study investigating FSW as a method for joining the lids on copper canisters for the long term storage of nuclear waste, the development of microstructure and heat flow during the FSW process was experimentally investigated. The microst…

Variations in microstructure in friction stir welds in AA 7449 (Al, 2.2%Mg, 8.2%Zn, 1.7%Cu, 0.12%Si, 0.15%Fe, 0.2%Mn, 0.05%Cr, 0.25 T plus Zr) in the initially overaged (T7) condition were studied. Isothermal heat treatments were conducted at 350 an…

The weldability of zirconium-titanium alloy joints fabricated by means of friction stir welding (FSW) was investigated. Sheets (thickness 3 mm) of Zr-Ti alloy (Zr, 41%Ti, 4%Al, 3%V) underwent FSW with a tungsten-rhenium alloy (W, 25%Re) tool with an…

A fully coupled thermomechanical three dimensional finite element (FE) model was developed to analyse the thermomechanical conditions, including material flow and heat generation, at the tool/matrix interface in friction stir welding. The model was …

AA 2219 aluminium alloy sheets (thickness 2.5 mm) were joined by friction stir welding (FSW) and an investigation was undertaken into the relationship between joint mechanical properties, the torque generated by the spindle motor and process variabl…

The microstructure and age hardening of friction stir welds in aluminium alloy plate 2014A-T651 (Al, 4.42%Cu, 0.79%Si, 0.62%Mg) and 7075-T651 (Al, 5.99%Zn, 2.72%Mg, 1.46%Cu) were investigated. Single sided butt welds were produced, temperatures bein…

In relation to the requirement for automatic inspection of weld quality during the friction stir welding (FSW) process, the "MonStir" process monitoring system was developed to analyse measured process forces and their frequency spectra, and an inve…