Investigation and Characterization on Metallurgical Mechanical and Corrosion Properties of TIG and Double Pulse TIG Welding of Nitinol

Abstract

In this current global scenario, where materials with unique properties are newlineneeded, it is important to develop Shape Memory Alloys (SMA) with good newlinemechanical and corrosion properties. As SMA is sensitive to heat, it is difficult to newlinefabricate complex shapes with good functional properties. For the manufacture of newlinecomplex biomedical implants, welding plays a key role. In this work, an attempt was newlinemade to study the effect of Heat Input (HI), pulse duration and Post Weld Heat newlineTreatment (PWHT) on metallurgical, mechanical and corrosion characteristics of newlineautogenous Tungsten Inert Gas (TIG) and Double Pulse Tungsten Inert Gas newline(DP-TIG) welding of NiTinol. For this research, bead-on-plate welding was newlineconducted on a 1 mm NiTinol sheet. Initially, TIG welding was performed on newlineNiTinol with four distinct HI. The welded samples were metallurgically newlinecharacterized using a Field Emission Scanning Electron Microscope, Electron newlineBackscatter Diffraction, and X-Ray Diffraction. The microstructure of TIG welded newlinesamples showed B2 austenite phase with columnar grains. With increase in heat newlineinput in TIG welding, bead width, temperature hysteresis increased whereas and newlinetensile strength is decreased newline