TWI Digital Library

Friction Stir Welding (FSW) is a relatively new technique which utilizes frictional heating combined with a forging pressure to produce virtually defect-free high strength bonds. Although considerable experimental work has been reported in the liter…

Friction stir lap diffusion welding was employed to fabricate dissimilar AA 6060 aluminium alloy/mild steel joints and mechanical testing and metallurgical examination of the weldments were undertaken to investigate the effect of microstructure form…

Similar overlap and dissimilar butt joints were fabricated by friction stir spot joining of AA 6061-T6 (Al, 1-1.1%Mg, 0.66-0.67%Si) and AA 5052-H34 (Al, 2.58%Mg) sheets of thickness 1 and 2 mm, respectively, and microstructural analysis was used to …

An finite element method (FEM) model, considering variables such as tensioning level, heat input and sheet geometry but ignoring mechanical tool effects, was developed to investigate the efficacy of the mechanical tensioning technique for controllin…

A 3D computational fluid dynamics model was developed to conduct numerical simulations of heat generation, material flow and temperature profiles during reverse dual-rotation friction stir welding, a process variant in which the tool pin and the ass…

SiC particle reinforced 2124Al metal matrix composite (MMC) plates (thickness 8 mm) were joined by friction stir welding (FSW) and the relationship between process parameters, weld defect formation and joint mechanical properties was investigated. T…

The microstructures and strengthening mechanisms during friction stir processing (FSP) of AZ91 (Mg, 9%Al, 1%Zn) die-cast and Mg-Y-Zn (Mg, 5.9%Y, 2.6%Zn and Mg, 5.5%Y, 4.3%Zn) cast alloys were investigated and the effect of second phase particle disp…

Numerical simulation of the friction stir welding (FSW) process was undertaken by means of an arbitrary-Lagrangian-Eulerian (ALE) formulation and a fully coupled thermomechanical analysis was performed to account for the heat flux generated by plast…

The results of a programme to establish self reacting friction stir welding for thin gauge (less than 3 mm) aluminium alloy applications are reported divided into the five major phases: tool development; joint evaluation; strength optimisation; prot…

Modelling tools were developed to describe the relationships between process parameters, microstructural evolution and mechanical properties of the weld in friction stir welding (FSW). Experiments were conducted using aluminium alloy 6056. Initial t…

Work from two projects is described: "Qualistir" for the on-line quality control of friction stir welding in aluminium (by ultrasonic phased array examination of butt welded Al 7075); and a TWI feasibility study on inspection of Al 5083 butt and lap…

Computational fluid dynamics (CFD) methods were used to model the metal flow in the friction stir welding (FSW) process in order to optimise the pin profile to minimise the traversing force; welding experiments were carried out to validate the findi…

The influences of the thermal and mechanical stresses experienced during friction stir welding on the structure of coarse-grained aluminium alloy 2519-T87 were investigated. Plate of 25 mm thickness was welded at a speed of 1.5 mm/s, using a tool sp…

Friction stir welding (FSW) was investigated in aluminium alloys used in aircraft structures. Extruded shapes in alloys 2024 (Al, 4.96%Cu), 7475 (Al, 5.96%Zn, 2.57%Mg, 1.62%Cu) and 7050 (Al, 6.29%Zn, 2.36%Mg, 2.00%Cu) were welded; welds were evaluat…

A procedure has been developed for repairing welds made by friction stir welding (FSW) in cases where the tool breaks during welding. It involves the following stages: excavating the broken FSW tool, milling out a slot across the hole, machining an …

The quality of friction stir welds of butt joints (including the use of inserts to simulate compensation for poor fit up) between aluminium alloys 5083-H12 (Al, 4.6%Mg, 0.6%Mn, 0.3%Si) and 6082-T6 (Al, 0.7%Mg, 0.9%Si, 0.5%Mn), was evaluated. The wel…

The influence of friction stir welding on the microstructure and mechanical properties of aluminium alloy 6061 was investigated. Aluminium alloy 6061-T651 plate of 6.4 mm (0.25 in) thickness was friction stir welded and the joints characterised by o…

The microstructure, crystallographic texture and grain distribution were determined in a transverse cross section of a friction stir weld and in a plan-view section through the embedded friction stir welding (FSW) tool. The weld was obtained by FSW …

The microstructure, mechanical properties and fatigue behaviour of friction stir welded (FSW) and MIG welded butt joints in aluminium alloy 2519-T87 (Al, 5.3-6.4%Cu, 0.1-0.5%Mn, 0.02-0.1%Ti) plate of 25.4 mm thickness were compared. Friction stir we…

The distortion, mechanical properties and microstructure of friction stir, submerged arc and GMA welds in HSLA-65 steel (0.09%C, 1.32-1.39%Mn, 0.01-0.06%Ni, 0.041-0.067%V, 0.03-0.035%Nb) and DH-36 steel (0.18%C, 0.90-1.60%Mn, 0.25%Cr, 0.40%Ni, 0.08%…