Ultrasonic-assisted Pulsed TIG Welding (U-P-TIG) of Inconel 690 for Nuclear Power Plants

Abstract Inconel 690 has been extensively used in steam generator tubing materials for pressurized water reactors. In order to improve the weld quality of 690, ultrasonic-assisted pulsed tungsten inert gas (TIG) welding is studied. this study, macrostructure, microstructure, and mechanical properties weldments welded by TIG with without ultrasonic assistance were investigated. The microstructures fusion zone (FZ) heat-affected zones (HAZ) examined an optical microscope Electron Backscatter Diffraction (EBSD) technique, weldment compared through tensile impact tests. Experimental results indicate that base metal (BM) was composed equiaxed crystalline austenite, austenite grains obviously grown; columnar austenite. Besides, effective refining structure improving strength toughness metal.