TWI

A description is presented of the friction stir welding (FSW) machine developed for fabrication of the external fuel tanks for the Space Shuttle. The cylindrical part of the tanks was composed of curved panels welded into barrels with welds of const…

Rotary friction welding was employed to fabricate joints between an ASTM A36 steel pipe (0.11%C, 0.2%Si, 0.92%Mn, 0.02%Cr, 0.02%Nb, 0.03%Al) and an API 6A flange and microstructural analyses and mechanical tests were undertaken to investigate the se…

With regard to the development of the stationary shoulder friction stir welding (FSW) technique as a long term loading joining process offering enhanced weld seam mechanical properties, an investigation is presented into coordinated material flow be…

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…

An experimental investigation was made of the effect of welding tool shape on welding defects and material flow during friction stir welding (FSW) of dissimilar materials. Friction stir welding tools used had tool shoulders of tool steel and the pro…

Friction stir spot welding (FSSW) was employed to fabricate lap joints in hot extruded AZ31 magnesium alloy sheets (thickness 2 mm), and the effect of introducing nanostructured SiC particles (mean size 40 nm) on the microstructure and mechanical pr…

An investigation is presented into the joint efficiency and tensile properties of welded joints in various structural aluminium alloys prepared by friction stir welding (FSW), looking at the effects of compositional differences in the parent metals …

A friction stir welding (FSW) process based on the use of a self-reacting pin tool (SRPT) was developed for the joining of solid and hollow extrusions for aluminium railway car body structures; the mechanical properties of welded joints were investi…

Optical microscopy, SEM and electron backscattering diffraction techniques were employed to investigate the microstructural evolution and solid-state phase transformations during friction stir spot welding (FSSW: also known as friction spot joining)…

Al, 50%Si alloys were joined by friction stir welding (FSW) on spray deposited sheets (thickness 1.5 mm) for butt welding and powder metallurgy plates (thickness 10 mm) for surface welding and the welded joint surface quality and microstructure were…

Friction stir welding was employed to fabricate dissimilar joints between 5A06-H112 aluminium alloy (Al, 5.8-6.8%Mg, 0.5-0.8%Mn) and 304L stainless steel (0.03%C, 18-20%Cr, 8-11%Ni) and material flow behaviour was investigated by microstructure obse…

With regard to the problem of parameter development for friction stir welding (FSW) of workpieces with 3D joints, a self-tuning algorithm is presented based on the tool-workpiece thermocouple (TWT) method for temperature measurement to facilitate th…

A Lagrangian particle model based on the SPH (smooth particle hydrodynamics) method was developed for friction stir welding (FSW) of similar and dissimilar materials by disregarding elastic deformation and describing plastic deformation by the Johns…

An investigation is presented into the metallurgical features of welded joints in various structural aluminium alloys prepared by friction stir welding (FSW) and into the microstructure and hardness distribution of the weld zone. The experimental sp…

The stationary shoulder friction stir welding (SSFSW) process was employed to fabricate defect-free joints in a variety of aluminium alloys and experiments were undertaken to investigate the microstructure and mechanical properties of the joints. Th…

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 …

The Skew-Stir™ variant of friction stir welding (FSW), in which the axis of the tool is at an angle to that of the machine spindle, is described. The technique provides an improved path for metal to flow around the tool during welding, resulti…

Stress corrosion cracking in friction stir welded aluminium alloy joints was investigated using two alternative techniques. Aluminium alloy 7050-T7541 (Al, 5.7-6.7%Zn, 2.0-2.6%Cu, 1.9-2.6%Mg, 0.15%Fe, 0.12%Si) plate of 6.35 mm (0.25 in) thickness wa…

Synchrotron x-ray diffraction measurements were used to obtain residual stress state data for welded joints made by friction stir welding (FSW) in AA-5083-H321 aluminium alloys as a function of process parameters (rotational speed and feed rate). Bu…

An investigation is presented into the fatigue properties of welded joints in various structural aluminium alloys prepared by friction stir welding (FSW) and the results are compared with those measured on MIG welded joints. The experimental specime…