TWI

An investigation was undertaken to examine the interactions, required process adjustments and resultant joint properties associated with conventional and robotic stationary shoulder friction stir welding (SSFSW) for scaled tool geometries. In order …

The microstructure, hardness, tensile strength and fracture toughness of friction stir welds in cryogenic tanks made from standard AA2219 AlCu alloy and advanced AA2195 AlCuLi alloy (5 mm thickness) were investigated. AA2195 has relatively low densi…

With regard to the need to control process temperature in friction stir welding to enhance process stability and weldment mechanical properties, a feedforward feedback control system was designed based on two nonlinear single input single output (SI…

Controlled force monitored plug-in tests were undertaken to investigate the influence of rotational speed and to analyse flow regimes during friction stir welding (FSW) of different aluminium alloys. Experimental specimens comprised sheets (thicknes…

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 …

Modified Gleeble hot torsion testing was used to simulate four microstructure regions in HSLA-65 steel (0.07%C, 0.24%Si, 1.5%Mn, 0.14%Cr, 0.34%Ni, 0.25%Cu, 0.06%Mo) joints fabricated by friction stir welding (FSW) and the results were verified by op…

Magnesium alloy AZ31H-H24 sheet of 3.175 mm in thickness was friction stir welded (FSW) using an H-13 tool having a shoulder of 20 mm diameter and a slightly tapered pin (4.5-5.5 mm diameter). Welds were made at 1000-2000 rpm and 20-300 mm/minute. T…

The effects of rotation speed, welding speed and Z-axis force on process response variables (power, specific energy, torque, X-axis force) and properties (nugget hardness, strength and ductility, nugget grain size and HAZ hardness) of AA2524-T351 fr…

High alloy tool steel H13, silicon nitride(Si3N4) and tungsten carbide (WC) bonded with 10%Co cylindrical pin tools (12.5 mm diameter) were evaluated for the friction stir welding of aluminium alloy 6061 containing 20 wt% alumina by determining an e…

Experimental measurements and finite element modelling were undertaken to investigate the deposition of AA1050 commercially pure aluminium layers on AA 2024-T351 aluminium alloy substrates by friction surface cladding (FSC). Experiments were perform…

A round robin investigation was made to determine if defects found using the non-destructive evaluation (NDE) techniques of ultrasonic phased array and x-ray inspection, can be identified by a real-time, feedback-based friction stir weld analysis to…

An investigation is presented into the fabrication of welded joints in high strength aluminium alloys by friction stir welding (FSW) and into the application of the technology for manufacturing lightweight aircraft structures. The materials consider…

Experimental measurements and finite element modelling were undertaken to investigate the deposition of AA1050 commercially pure aluminium layers on AA 2024-T351 aluminium alloy substrates by friction surface cladding (FSC). Experiments were perform…

A modified friction stir lap welding process was developed to encase uranium alloy foil in an aluminium jacket and results were compared with two other bonding methods for fabricating monolithic fuel plates, namely hot isostatic pressing and transie…

The plastic flow and microstructure of friction stir welded butt joints in aluminium alloy 7050-T7451 (Al, 6.2%Zn, 2.2%Mg, 2.3%Cu, 0.01%Zr) of thickness 7 mm were investigated. Cylindrical compression test samples (5.1 mm diameter and height) machin…

The results of two testing programmes dealing with the metallurgical and mechanical properties of friction stir weldments (thickness 6 and 25 mm) in the aluminium alloys 2024, 5083, 6082/6060 and 7075 are reported, and a systematic study of the key …

An integrated multi-physics model was employed to predict the temperature distribution, the post-weld grain size distribution and the local subgrain size distribution around the pin during friction stir welding (FSW) of 6061 aluminium alloys. The mu…

The Taguchi method was employed to determine optimum process parameters for friction stir welding of dissimilar joints between AA 6061 (Al, 0.84%Mg, 0.54%Si, 0.4%Fe, 0.24%Cu) and AA 7075 (Al, 5.58%Zn, 2.28%Mg, 1.6%Cu) aluminium alloys. Welding was p…

A discussion is presented on developments in polycrystalline cubic boron nitride (PCBN) tool design for use in the friction stir welding of high temperature materials such as steels. Improvements in tool material grades, tool design and FSW equipmen…