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 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 (291, 251 and 195 MPa), ultimate tensile strength (464, 387 and 231 MPa) and percentage of elongation or ductility (19, 16 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 fracture of weldments for all three conditions are found at 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 dimples and microvoids are found in the fractured region which derives the ductile failure.