Study on the High Temperature Tensile Properties of Aerospace Grade Hastelloy X Joined by Pulsed Current Arc Welding 2020-28-0421

The fabrication or repairing of aircraft components made of Hastelloy X to be resolved using an arc welding technique. In this study, Hastelloy X was joint with ERNiCrCoMo-1 filler by pulsed current gas tungsten arc (PCGTA) welding. The high temperature tensile property of the weldment has been evaluated at three different temperatures such as 700 °C, 800 °C and 900 °C. The tensile properties such as yield strength (294, 259 and 205 MPa), ultimate tensile strength (475, 396 and 245 MPa) and percentage of elongation or ductility (17, 14 and 11 %) follows the similar trend with temperature at 700 °C, 800 °C and 900 °C respectively. It revealed the values of all the properties are decreased as the temperature increased. The lowest strength was evaluated for weldment at 900 °C. The high temperature tensile test also revealed that the fracture of weldments for all three conditions is found at the weld centre (WC). Even though, the failure happened at WC, the high temperature tensile strength of the weldments revealed that values are more or less equal to the base metal (Hastelloy X) values at 700 °C, 800 °C and 900 °C. The SEM fractography has been performed to find the tensile failure mode of weldments. The ductile dimples, ductile tear ridges and lesser cleavage-facet are found in the fractured region which derives the ductile failure.