Possibilities for Application of Friction Stir Welding Process to Titanium TiGr2

Abstract

The interest in friction stir welding (FSW) of different categories of light metallic materials, including titanium and its alloys, has growing in recent years.Due to favorable ratio between strength and density, titanium and its alloys have increasingly used in applications in priority areas (e.g. aeronautics and in aerospace). Having the best impact strength and good corrosion resistance, these materials find applications in chemistry, nuclear and military technology.This paper present the results obtained at friction stir butt welding of TiGr2 sheets with thickness 4mm.The experimental program has developed using three categories of welding tools: with smooth cylindrical pin and flat shoulder, with tapered pin and flat shoulder, respectively with tapered pin having four plane chamfers and flat shoulder. The welding experiments have made using combinations of tools and welding parameters.The control of FSW welding process of titanium TiGr2 sheets has done using an innovative method namely infrared thermography technique.The research program has focused on development of some welding tools and welding regimes correlated with obtaining some of better mechanical characteristics for welded joints.Results obtained to the friction stir butt welding of titanium TiGr2, lead to conclusion that welding joints without defects and with good mechanical characteristics can be obtained, if are known and met the specific requests regarding applying of FSW process to this type of material.