TWI Digital Library

The evolution of microstructure and mechanisms occurring at the (sub)micron scale during friction stir spot welding of transformation induced plasticity (TRIP) steel were investigated. Welds were made in TRIP690 steel (0.24%C, 1.6%Al, 2%Mn, 0.3%Si, …

A short review is presented of the development of a friction stir welding process for steel and other hard metals using W-Re tool materials to produce repeatable, thick-section welds with minimal tool deformation. Issues discussed include: W, 25%Re …

Some numerical and experimental results are presented to illustrate the ability of the SignaStir laser ultrasonic testing system to monitor the occurrence of voids, cavities and lack of root penetration defects during friction stir welding (FSW). A …

A project to introduce friction stir welding for aluminium shipbuilding in Taiwan is described. The advantages of FSW compared with arc welding for this application are summarised. Stages of the project are outlined, covering work with local tool fa…

The use of a full-length welding process to repair defective friction stir welded (FSW) butt joints in aerospace aluminium alloys was evaluated. Lack of penetration, offset and tunnel defects were investigated in AA6156-T6, AA2198-T8 and AA2024-T3 a…

Friction stir welding was employed to fabricate bead-on-plate welds on AA 6063 aluminium alloy sheets (thickness 5 mm) and dissimilar joints between AA 6063 and S45C carbon steel plates (thickness 6 mm), and the influence of weld shape on microstruc…

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 …

Friction stir welding was employed to fabricate welded joints in Ni-free 18%Cr, 2%Mo, 0.85%N austenitic steel sheets (thickness 3 mm) and the gradient characteristics of the microstructures and mechanical properties were investigated along transvers…

The concept and theoretical principles of friction flow welding are presented. Numerical simulation using 'Deform-3D' software was used to compared and optimise the process. The applicability of friction flow welding to different aluminium alloys wa…

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…

A report is presented into the "RoboFSW" project, intended to qualify a high payload articulated arm robot for friction stir welding (FSW); hardware modification and control system integration are described and 3D FSW capability is reported for circ…

Two abutting plates (thickness 6 mm) of Al 6061-T6 and cold rolled AISI 1018 mild steel were friction stir welded along the butt joint with the steel and aluminium, respectively, on advancing and retreating sides, and the relationship between proces…

The surface quality, microstructure and crystallographic texture were investigated as a function of traverse speed for friction stir welds of Ti-6Al-4V, produced using static shoulder tools consisting of a tungsten-rhenium probe and a silicon nitrid…

Orientation imaging microscopy was employed to characterise the stir zone microstructure in relation to the defect formation tendency and evaluate the peak temperature at different locations in friction stir welded Ti-6%Al-4%V specimens. Welded join…

Welded joints were fabricated in AZ31 magnesium alloy (Mg, 3.01%Al, 0.9%Zn, 0.5%Mn) sheets (thickness 2 mm) by bobbin tool friction stir welding (BTFSW) and the influence of process parameters (rotational and welding speeds) on their microstructure …

The feasibility of short-cycle friction stir spot welding for joining thin sheet aluminium alloys and steels, both galvanised and ungalvanised, was evaluated. Welds were made between 6111-T4 AlMgSi alloy (Al, 0.75%Cu, 0.25%Fe, 0.75%Mg, 0.2%Mn, 0.69%…

A fully coupled thermomechanical formulation was proposed for the numerical modelling of friction stir welding (FSW) to facilitate the efficient simulation of different types of material flows and accurate computation of the resulting thermomechanic…

With regard to the capability of ultrasonic vibration enhanced friction stir welding (UVeFSW) to improve weld formation quality as well as the microstructure and mechanical properties of the welded joints, experiments were undertaken to clarify the …

The friction stir welding (FSW) process was determined for stiffener to skin lap joints of different aluminium alloys (similar 2024 T3, similar 2139 T3 and T8, dissimilar PA 765 T79 extrusion on 2139 T8 skin) and FSW procedures with retractable pin …

The feasibility of friction stir welding (FSW) for welding aluminium alloy 7020, used for the construction of light armoured fighting vehicles, was investigated and compared with MIG welding. Two joint configurations were tested: butt welding in 100…