TWI Digital Library

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 …

Aluminium alloy fusion welds were modified by friction stir processing (FSP) as a function of FSP location and tool design, and differences between the FSP locations and tools were quantified by microstructure and mechanical property measurements (u…

As part of a project to develop a physical-mathematical model and software for thermal simulation of the friction stir welding (FSW) process, an initial version "FricSim2.2" was created and verified, using the software tool "SpotFSW" to convert the …

The incorporation of strips of copper foil in friction stir welded aluminium alloy plate was evaluated for flow visualisation without disturbing the welding process. The strips, of 0.1 mm thickness, were placed in various longitudinal and transverse…

The design and construction of a prototype fixture and a corner fixture for making 90 degree corner joints in aluminium alloys by friction stir welding (FSW) are described. The requirements for a FSW weld fixture are outlined. The fixtures were test…

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…

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…

The friction stir welding of copper for the production of spent nuclear fuel storage disposal canisters was investigated. Initial trials were conducted on UNS-C10100 plate of 10 mm thickness. The high temperatures required the use of a sintered tung…

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 stop-action technique was used to stop tool motion during friction stir welding of aluminium alloys in order to study the interactions between the parent material and welding tool pin in the keyhole. Welds were made in 25 mm thick Al-Cu-Li 2195 pl…

Following an overview of friction stir spot welding (FSSW) for potential automotive applications (including robotic FSSW in poke welding and C-frame configurations, and pedestal FSSW machines for manual, automatic or robotic use), a FSSW process dev…

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…

This paper describes the joining criterion for lap joining of dissimilar metal materials of aluminum and stainless steel by friction stir. A criterion for evaluating the joined state or non-joined state is proposed, which is led by the concept based…

Experimental measurements and thermal modelling were used to determine the transient heat loss into friction stir welding tools and so calculate the welding efficiency. Energy inputs were determined from force and torque measurements made whilst per…

Experimental methods were developed to track material flow and mixing during the friction stir welding (FSW) process. Experiments were conducted with butt joints of 6.35 mm (0.25 in) thickness 7050-T7451 aluminium alloy plates. The FSW tool was H13 …

Alternative friction stir welding tool shoulder materials to improve welding speed and quality were evaluated. The materials, which were compared with tool steel using a tool designed for exchangeable shoulder inserts, were: nitrided tool steel, Inc…

As part of a study investigating friction stir welding (FSW) as a method for joining the lids on copper canisters for the long term storage of nuclear waste, finite element modelling was used to analyse heat flow and material flow and the developmen…

The effects of tool shoulder size and tilt angle on the formation of weld zones during the friction stir welding of aluminium alloys were studied. Aluminium alloy 5083 (Al, 4.2%Mg, 0.2%Si, 0.6%Mn, 0.15%Fe, 0.09%Cr, 0.09%Zn, 0.06%Cu, 0.02%Ti), an all…

The microstructure and mechanical properties (hardness profiles, tensile strength) of friction stir welded (FSW) joints of ZL114A cast aluminium alloy (Al, 6.5-7.5%Si, 0.45-0.6%Mg), a material of interest for applications in the aerospace industry, …

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…