TWI

Friction stir welding (FSW) studies were undertaken to join sheet and plate specimens of aluminium alloys in a butt joint configuration, and design of experiments methods were employed to optimise process parameters with respect to weldment quality …

An experimental investigation is presented into the precipitation and hardening mechanism during FSW (friction stir welding) of Ni model alloys (Ni, 20%Cr, 2%Al, 2%Ti and Ni, 20%Cr, 3%Al, 3%Ti) in which Al and Ti contents were varied to control the …

Lap joints between 2 mm aluminium alloy sheet in 2024-T3 (Al, 4.4%Cu, 1.5%Mg, 0.6%Mn) and 7075-T6 (Al, 1.6%Cu, 2.5%Mg, 0.23%Cr, 5.6%Zn) were prepared and evaluated. The welds were produced using a range of welding and tool speeds, with a non-threade…

An investigation is presented into pore formation and grain growth in aluminium alloys during TIG welding after friction stir welding (FSW), for reasons of repair or fabrication, and into two methods to suppress these problems. The material studied …

The design, fabrication and evaluation of a portable friction stir welding (FSW) system for the in-situ field repair of aluminium structures to a depth of 6 mm is reported. The conceptual design of the FSW machine was produced using a dual-track app…

A review is presented of the development of W, 25%Re friction stir welding (FSW) tool materials for application to steels and hard metals, such as titanium and nickel-based superalloys. Issues discussed include: the DUST (dual use science and techno…

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…

An investigation was undertaken into the development and wear performance of friction stir welding (FSW) tools made from precipitation strengthened Ir-containing nickel-based superalloys (Ni, 25%Ir, 14%W, 4%Al) during FSW of Ti, 6%Al, 4%V alloys. Th…

Numerical modelling and experimental measurements were undertaken to investigate the extension and microstructure of the HAZ during friction stir welding (FSW) of 7075 aluminium alloy (Al, 5.86%Zn, 2.37%Mg, 1.91%Cu) thin sheets (thickness 1.2 mm). W…

Process force and discontinuity models were derived to estimate the forces observed in friction stir welding (FSW) in order to develop a method of detecting discontinuities during FSW using physics-based process modelling. FSW welded joints with and…

Models to predict the precipitate and grain size evolution in AA7449 aluminium alloy friction stir welds are presented and compared with experimental data. Bead on plate welds on 3.2 mm thickness sheets of composition Al, 8.4%Zn, 2.1%Mg, 1.8%Cu were…

With regard to the application of friction stir welding (FSW) to the production of launcher tanks holding cryogenic liquids, an investigation was undertaken to establish a robust and industrialised FSW process for AA 2219 alloys in T87 and T851 cond…

Fatigue crack growth in friction stir welded (FSW) aluminium alloys 2024-T3 and 6013-T6 were predicted using two commercial software programs, ESACRACK and AFGROW in order to facilitate lifetime predictions of FSW aircraft structures. The following …

Evaluation of phased array ultrasonic inspection for the detection of typical friction stir weld defects is reported. Characteristics of friction stir welds with respect to inspectability are described. Phased array operation is outlined. A variety …

Friction stir welding of aluminium alloys suitable for railway and shipbuilding applications was investigated. Sheet of 4 mm thickness of alloys 6N01-T5 (Al, 0.7%Mg, 0.6%Si, 0.1%Cu) and 5083-H112 (Al, 4.7%Mg) were friction stir welded, and the joint…

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 influence of weld length on pin breakage during friction stir welding (FSW) of aluminium alloy was investigated. Tool geometry, microstructure, pin diameter and the occurrence of cracking were studied during welding. Welded joints were made in 7…

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…

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…