Weldability Investigation of Super-duplex Steel Hollow Pipes Welded by Gas Tungsten Arc Welding Process

This paper investigates the weldability of super-duplex steel hollow pipes, which are welded by Gas Tungsten Arc Welding (GTAW) process, using destructive and non-destructive tests. Non-destructive inspections were performed by visual inspection and radiography, which indicate the proper quality of the performed welds. Material analysis, metallographic, tensile and hardness tests have been performed for different welding positions. The effects of the welding position on the microstructure and mechanical properties of the welded specimens were investigated. The results of the metallographic test reveal the good balance between austenite-ferrite phases in the weld zone. According to materials analysis, chromium to nickel weight percent is higher at the 12 o’clock position. The hardness test results show that the average hardness is the same in different welding positions. The presented results indicate the good weldability of the super-duplex steel pipes fabricated by the GTAW process. The weldability assessment of the GTAW super-duplex steel hollow pipes using both destructive and non-destructive tests, at different welding positions, is an innovative research.