Investigation on welding characteristics of aerospace materials – A review

Abstract

Titanium and nickel based alloys possess excellent properties and are found wide applications in producing aerospace components. Welding of these superalloys has always been a challenging task for researchers. The high dynamic shear strength and higher strain hardening tendency makes welding process difficult. Poor penetration, microfissuring at heat affected zone (HAZ), loss of strength in HAZ and poor mechanical property on weld fusion zone (FZ) are some of difficulties encountered in different welding processes during the welding of nickel based super alloys. This work reviews the published literatures in the area of welding investigations of nickel based superalloys by different welding processes viz., gas tungsten arc welding (GTAW),gas metal arc welding (GMAW), electron beam welding (EBW), laser beam welding (LBW) and friction stir welding (FSW). Most of the welding processesare found suitable for welding nickel based alloys while EBW and LBW processes offeradvantages of low heat input, high weld depth-to-width ratio, narrow HAZ, reduced distortion, and excellent mechanical property compared with arc welding of nickel based alloys.Apart from experimental investigation of welding, modeling and optimization of process parameters for obtaining better weld bead geometry were attempted by the researchers.