TWI

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…

Friction stir welding experiments were undertaken on 2195-T8 (Al, 3.99%Cu, 1.09%Li) alloy sheets (thickness 5 mm) and the weldability, microstructure and mechanical properties of the fabricated butt joints were investigated. Welding was performed us…

An experimental investigation was undertaken to examine how tool pin induced material flow and intermetallic growth conditions affect the formation of discontinuity during friction stir lap welding of dissimilar Al-Cu joints. The materials comprised…

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…

The fine scale precipitation in the nugget zone and in the HAZ of a weld in aluminium alloy AA-6082 (Al, 0.7%Mg, 0.5%Mn, 0.9%Si) of thickness 5-10 mm made by friction stir welding (FSW) was examined using transmission electron microscopy. The dissol…

The relationship between microstructure and properties in friction stir welding was studied. The effects of grain size, particle size and distribution, and dislocation density on weld strength in friction stir welds in work-hardenable Al alloy AA 52…

A friction stir welding tool with a variable length probe (suitable for variable thickness joints, repairs and circumferential welding) was developed and evaluated for the welding of aluminium alloy 2195. Tapered sheet, of both increasing and decrea…

Friction stir welding (FSW) was employed to fabricate a single overlap joint between sheet specimens (thickness 1.5 mm) of an AA 6181-T4 aluminium alloy and ZStE-340 high-strength steel, and weld phase composition, microstructure and mechanical prop…

The deformation behaviour and microstructural evolution of friction stir processed Zn, 22%Al rolled sheet (thickness 3 mm) were compared with those of the corresponding superplastic alloy. Friction stir processing was performed at a rotational speed…

Friction stir welding experiments between AA 6063 aluminium alloy and S45C carbon steel (thickness 6 mm) were performed, and the effects of heat input on the butt joint macrostructure (cavities formed at weld interface), hardness and plastic flow of…

Several kinds of Co-based alloys with different mechanical properties (e.g. high temperature strength, hardness, wear resistance and gamma-solvus temperature) were designed for friction stir welding (FSW) tool applications by varying chemical compos…

Friction stir welding (FSW) experiments were conducted on commercially pure titanium sheet (thickness 3 mm) to identify the optimum tool material and process conditions; the microstructure and mechanical properties of the welded joints were determin…

Dissimilar lap joints were fabricated between 6022 aluminium alloy and SPCC low carbon steel using friction stir welding (FSW) and the effect of probe tip position on microstructure and mechanical properties was investigated. FSW was performed at a …

Friction stir welding (FSW) experiments were conducted on a variety of materials and grain structure development, material flow characteristics and crystallographic texture formation were examined by high-resolution electron backscatter diffraction.…

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-…

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…

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.…