Plasma transferred are repair welding of the nickel-base superalloy IN-738LC

Abstract

Plasma transferred are welding (PTA) has been considered a promising process tea restore worn areas of land-based gas turbine blades and vanes. The objective of this investigation was to study the effect of PTA welding on the repairing of IN-738LC superalloy components, Tensile tests were conducted on specimens welded with various combinations of parameters, Room temperature, 760 degrees C, and 980 degrees C were selected Its tensile test temperatures, High-temperature phase transformed, during solidification, were identified by differential thermal analysis (DTA), The weld-pool shapes and microstructures of welded specimens prepared by various welding parameters were evaluated by optical metallography (OM), a scanning electron microscope (SEM) equipped with energy dispersive x-ray spectrometer (EDS), and microhardness testing. Results of this study showed that PTA welded specimens exhibited 96% nominal tensile strength of IN-738LC base materials, Specimen failure was observed predominantly in the base materials instead of in the heat-affected zone (HAZ) for gas tungsten are weld (GTAW) repair weldments, IN-738LC is considered susceptible to weld cracking during fusion welding; however, using a low-input heat repair welding process (PTA), cracking susceptibility could be minimized by the optimized welding parameters.