Search results for "Linear Friction Welding"

Infrared thermography for monitoring heat generation in a linear friction welding process of Ti6Al4V alloy

2017

Abstract The increasing use of titanium alloys in a wider range of applications requires the development of new techniques and processes capable to decrease production costs and manufacturing times. In this regard welding and other joining techniques play an important role. Today, solid state friction joining processes, such as friction stir welding, friction spot welding, inertia friction welding, continuous-drive friction welding and linear friction welding (LFW), represent promising methods for part manufacturing. They allow for joining at temperature essentially below the melting point of the base materials being joined, without the addition of filler metal. However, the knowledge of te…

Welding abilities of UFG metals

2018

Ultrafine Grained (UFG) metals are characterized by an average grain size of <1 μm and mostly high angle grain boundaries. These materials exhibit exceptional improvements in strength, superplastic behaviour and in some cases enhanced biocompatibility. UFG metals barstock can be fabricated effectively by means of Severe Plastic Deformation (SPD) methods. However, the obtained welded joints with similar properties to the base of UFG material are crucial for the production of finished engineering components. Conventional welding methods based on local melting of the joined edges cannot be used due to the UFG microstructure degradation caused by the heat occurrence in the heat affected zone…

On the linear friction welding process of aluminum alloys: Experimental insights through process monitoring

2013

Abstract Linear friction welding is a solid-state joining process for non-axisymmetric components in which joining of materials is obtained through the relative motion of two components under pressure. In the process the heat source is given by the frictional forces work decaying into heat determining a local softening of the material and eventually bonding conditions. A dedicated fixture was equipped with sensors for the in-process acquisition of variables regarding kinematics, dynamics and temperature levels. The results of an experimental campaign aimed to weld AA6082-T6 aluminum alloy parts are presented and a process window is identified for the used alloy.

Experimental and numerical study on Linear Friction Welding of AA2011 Aluminum Alloy

2014

COMPUTER AIDED ENGINEERING OF SOLID BONDING PHENOMENA

2014

Joining is a fundamental technological process in manufacturing used to create a single piece from two or more parts. Welding is still today one of the most popular joining techniques used in manufacturing allowing a permanent junction. Traditional welding processes are based on the melting of the materials to be joined. In this way, several defects may arise because of solidification problems, joints deformation due to elevated residual stress and metallurgical integrity of the joints (intermetallic, porosities, etc). As an example, some aluminum alloys present considerable problems the junction is carried out by traditional fusion welding methods. During the melting process, in fact, the …

Effective Linear Friction Welding Machine Redesign through Process Analysis

2014

Linear friction welding is a solid-state joining process developed for non-axisymmetric components in which the joining of the specimens is obtained through reciprocating motion and pressure. In the process, the friction forces work due to the high frequency oscillation and the pressure between the specimens is converted in thermal energy. In order to design an effective machine, relevant issues derive from the high frequency and the large inertial forces involved in the process. In this study, the authors describe the redesign of a preexisting prototypal machine for LFW processes. A machine redesign is needed when welding high resistant materials, i.e. steels or titanium alloys, with high …

Friction based Solid State Welding Techniques for Transportation Industry Applications

2014

Abstract Solid bonding based processes represent an effective solution in terms of both joints mechanical performances and sustainability. In the last years, both the academic and the industrial researchers focused their work on two solid-state processes: Friction Stir Welding (FSW) and Linear Friction Welding (LFW). The former, patented in 1991 by TWI, is used to weld sheet metal in different joint morphologies, i.e. butt, lap T and 3D joints. The latter has been known for several years, but a growing interest is observed in the last years due to the enhancement of the welding machines performances. LFW, used to join bulk components, is particularly suited for aeronautical and aerospace ap…

A novel linear friction welding based approach for sheet-bulk joining

2019

In the last decades, the development of new, flexible manufacturing processes caused the increase of the demands for highly customized complex functional parts in many industrial fields. The peculiar design of these components often overcome conventional sheet metal and bulk metal forming processes capabilities. In order to face this issue, new hybrid techniques, capable of exploit key advantages of different processes, have to be developed. In this paper, a novel approach based on the Linear Friction Welding process is proposed to obtain sheet-bulk joints. The feasibility of the technique on high specific strength alloys is investigated through an experimental campaign.In the last decades,…

Mappe di Lavorabilita’ per Giunti Misti di Alluminio Mediante Processo di Saldatura Linear Friction Welding

2014

Il Linear Friction Welding è un processo di saldatura allo stato solido in cui una parte fissa è forzata contro una parte che si muove con moto lineare alternato per generare calore attraverso l’attrito. Nel presente lavoro viene descritto lo studio effettuato per la realizzazione della giunzione mista mediante processo di Linear Friction Welding tra due leghe di alluminio che presentano proprietà meccaniche differenti, come la lega AA2011 e AA6082. Lo studio è stato condotto analizzando due differenti configurazioni determinate dalla posizione relativa delle leghe costituenti i provini da saldare. Per la realizzazione del processo è stata utilizzata una macchina prototipale dotata di senso…