Fundamental Investigations on Friction Stir Knead Welding

Process Mechanics in Friction Stir Welding of Magnesium Alloys: Experimental and Numerical Analysis

On the Solid Bonding Phenomena in Linear Friction Welding and Accumulative Roll Bonding Processes: Numerical Simulation Insights

Solid Bonding based welding processes allow to obtain defect free joints with low residual stress and low distortion. However, the engineering and optimization of solid bonding processes is difficult and requires a large number of time and cost consuming test trials. In this way, proper numerical models are essential tools permitting effective process design. The aim of this research was the comparison of the material process conditions during two different manufacturing processes taking advantage of the same metallurgical phenomenon, namely solid bonding. Linear Friction Welding, used to weld non-axisymmetric components and Accumulative Roll Bonding, used to increase the mechanical propert…

On the friction stir welding of titanium alloys: Experimental measurements and FEM model fine tuning

Friction Stir Welding (FSW) is a solid state welding process patented in 1991 by TWI; initially adopted to weld aluminum alloys, is now being successfully used also for magnesium alloys, copper and steels. Recently, research is focusing on titanium alloys thanks to the high interest that such materials are getting from the industry as welding of titanium alloys by traditional fusion welding techniques presents several difficulties due to high material reactivity resulting in bonding with oxygen, hydrogen, and nitrogen with consequent embrittlement of the joint. In this way FSW represents a cost effective and high quality solution. The study of the temperatures reached at the varying of the …

Effect of process parameters on the joint integrity in Friction Stir Welding of Ti-6Al-4V lap joints

Joining by forming technologies: current solutions and future trends

AbstractThe progressively more demanding needs of emissions and costs reduction in the transportation industry are pushing engineers towards the use of increasingly lightweight structures. This goal can be achieved only if dissimilar and/or new materials, including polymers and composites, are joined together to create complex structures. Conventional fusion welding processes have often been proven inadequate to this task because of the high heat input reducing the joint mechanical properties or even making the joining process impossible. Joining by forming technologies take advantage on the plastic deformation to create sound joints out of even very dissimilar materials. Over the last 25 y…

Review on mechanical joining by plastic deformation

Mechanical joining technologies are increasingly used in multi-material lightweight constructions and offer opportunities to create versatile joining processes due to their low heat input, robustness to metallurgical incompatibilities and various process variants. They can be categorised into technologies which require an auxiliary joining element, or do not require an auxiliary joining element. A typical example for a mechanical joining process with auxiliary joining element is self-piercing riveting. A wide range of processes exist which are not requiring an auxiliary joining element. This allows both point-shaped (e.g., by clinching) and line-shaped (e.g., friction stir welding) joints t…

Investigations on the Mechanical Properties and Formability of Friction Stir Welded and Laser Welded Aluminum Tailored Blanks