TWI

A review is presented of the progressive emergence of conceptual tools associated with friction stir welding (FSW) at the Marshall Space Flight Center, USA, from the discovery of the shear surface, wiping metal transfer and the invention of a kinema…

The design of a polycrystalline cubic boron nitride friction stir welding tool, tool holder and machine for use with high melting temperature materials is described. A polycrystalline cubic boron nitride truncated cone tool tip, capable of working a…

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…

A friction stir welding technology was developed to facilitate welding extruded profiles together as a whole side wall in an aluminium railway wagon for coal transportation. The material employed was an AA 6061-T6 alloy plate (thickness 7 mm). Some …

An investigation is presented into tool material development of large polycrystalline cubic BN blanks to facilitate friction stir welding of thick section steel specimens (thickness 9.5 or 20 mm). Tool materials were produced from 90% polycrystallin…

An apparatus was developed to analyse the contact condition between the rotating tool and the workpiece during friction stir welding, and empirical tests were performed to determine the friction conditions (static, dynamic and the transition from on…

An investigation is presented into the effect of a paint bake cycle on the performance of friction stir spot welded (FSSW) joints fabricated in heat-treatable 6111-T4 aluminium alloy automotive sheets (thickness 0.93 mm) using a pinless tool and sho…

The use of friction stir welding, as an alternative to bolted or riveted joints, for the assembly of Airbus wings is discussed. Issues considered include: cost reduction, weight reduction, joint quality, and enhanced in-service performance. Potentia…

An investigation is presented into the use of temperature control in two friction stir welding (FSW) research projects: to understand the effect of backing plate conductivity on process parameters and to study the influence of active FSW tool coolin…

The electrically assisted friction stir welding (EAFSW) technique, in which an electric current is fed through the workpiece to soften the metal by means of ohmic heating, is described and some trial experimental results are reported. The initial EA…

A numerical model based on the finite element method and axisymmetric thermo-elastic-plastic analysis was developed to describe the refill friction stir spot welding (RFSSW) process and to predict the temperature distribution in welded joints as a f…

Friction stir welding (FSW) experiments were undertaken on pure aluminium (A1050) sheets (thickness 5 mm), and the material flow during welding was visualised in 3D by x-ray radiography using a tiny spherical tungsten tracer. FSW was performed in po…

The material flows of aluminium and steel during friction stir welding were visualised in three dimensions using x-ray transmission radiographic real-time imaging. The movement of a miniature spherical tungsten tracer during welding was visualised u…

Torsion testing was carried out using a range of temperatures and strains to simulate the formation of nugget zone grain structures in friction stir welds of a typical aluminium alloy (7010) in order to investigate the formation mechanisms. Electron…

In relation to the challenges involved in temperature data acquisition and transmission associated with rotation of the friction stir welding (FSW) tool, an investigation is presented into a wireless temperature monitoring system based on thermocoup…

A real-time wireless temperature measurement system was developed to facilitate improved temperature measurement at the tool-workpiece interface and a closed-loop control system for friction stir welding (FSW) that maintains weld quality under vario…

With regard to the production of aluminium alloy T joints for stiffened panel construction by friction stir welding (FSW), an investigation is presented into the fabrication of FSW T joints with AA 6082-T6 alloys and the influence of welding paramet…

Tapered probe and parallel probe tools were employed in friction stir welding of thick section AA 6082-T6 aluminium alloy specimens (thickness 38 mm) and the effect of tool geometry on weldment microstructure and crystallographic texture was investi…

Friction stir welding (FSW) experiments were undertaken on commercially pure Ti and Ti-6%Al-4%V plates (thickness 6 mm) by incorporating nickel foil markers of varying thicknesses to reduce forging load, enhance surface finish, eliminate void format…

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…