Development and Process Verification of a Linear Friction Welding Platform for Small Axis-Symmetrical Ti6Al4V Components

Abstract

This paper reports on the developments of a study done to establish the feasibility of implementing Linear Friction Welding (LFW) as a joining technique for small axis-symmetrical Ti6Al4V samples. This work will attempt to facilitate the manufacturing of high-integrity small near-net-shape components for aerospace, automotive and medical applications. LFW is a solid-state welding technique that utilises frictional heat generated by the rubbing of surfaces under an axially applied load, thereby forming a weld at temperatures below the beta transus point. The technique is advantageous as it has the potential to reduce defects normally associated with conventional welding of this material. This paper will describe the development of an experimental platform, which will facilitate the evaluation of the influence of selected process parameters and their influence on joint integrity. Process parameters that will form the basis of this study include axial load (weld interface force), consumed length (axial shortening), oscillating amplitude and frequency. Welds made on this platform will allow for the characterisation of the microstructural change across the weld zone or regions exhibiting grain refinement, linking this to the mechanical properties of the joint region. The study will create an understanding of how process parameters can be manipulated to achieve optimum joint properties or assist in eliminating weld defects. Knowledge generated will form the basis for developing a bench-top LFW research platform, with a reliable closed-loop response system that will aid in studying the effects of welding parameters on joint integrity of small titanium components.